Main | Family List (MO) | Family List (INBio) | Cutting Edge Draft Treatments | Guidelines | Checklist | Citing | Editors Draft Treatments ARACEAE By M. H. Grayum English, final draft: placed 1/May/2000 Caladium Madison, M. 1981. Notes on Caladium (Araceae) and its allies. Selbyana 5: 342-377. 9 spp., SW CR to Bol. and the Guianas; 1 sp. in CR. Caladium humboldtii Schott, which differs from C. bicolor in its smaller size (leaf-blades always < 10 cm long) and freely suckering habit, is sometimes cult. in CR (Grayum & Hammel 9451; CR, MO). It has never been collected in fertile condition. Caladium bicolor (Aiton) Vent., Descr. pl. nouv. t. 30. 1801. Arum bicolor Aiton, Hort. kew. 3: 316. 1789. Terrestrial; stems cormose, to ca. 7 cm diam., usually ± flattened, subterranean or epilithic; plants with milky sap. Leaves spiraled. Petioles 15-85 cm, peltately attached, lacking a geniculum. Leaf-blades simple, 9-45 × 4.5-27 cm, ovate-cordate to sagittate, usually mottled or flushed with cream and/or reddish, ± glaucous below. Infls. 1 or 2 per leaf axil. Peduncles 23-50 cm, subterete. Spathe tube light green externally, usually purplish within at base; lamina whitish, abscising after anthesis. Spadix ca. 6-12 cm, with yellowish female region and whitish male and medial sterile zones; distal sterile appendage lacking. Fls. unisexual, naked; male fls. with 3-5 stamens connate in synandria; sterile male fls. with elongate synandrodia; female fls. without style; stigma depressed-hemispheric; ovary incompletely 2-locular; ovules numerous per locule on intrusive parietal placentae. Frs. whitish, many-seeded. Wet forests, over limestone on steep slopes, 300-600 m; Pac. slope, S from Z.P. La Cangreja; also cult. throughout as ornamental, and sparingly escaped. Fl. May, Oct. (cult.); fr. (young) Apr. (wild). CR, Col. to Bol. and E Braz. (Grayum & Hammel 9449; CR, MO) This familiar sp. is best recognized by its cormose habit, peltate, usually variegated leaf-blades, and milky sap. It closely resembles Colocasia esculenta, which has ± uniformly green leaf-blades (often with a medial purplish spot) and reddish sap. The latter sp. is sharply distinguished in fertile condition by its conspicuous distal sterile spadix appendage. Caladium bicolor has long been regarded as a South American sp., but the following CR forest populations are surely native: Z.P. La Cangreja (J. F. Morales & Rojas 5355, INB); Fila Retinto, above Palmar Norte (Grayum & Hammel 9546; CR, MO); and Fila de Cal, above Ciudad Neily (Hammel 14162, MO). Chlorospatha Madison, M. 1981. Notes on Caladium (Araceae) and its allies. Selbyana 5: 342-377. 16 spp., CR to Ecua.; 1 sp. in CR. Chlorospatha croatiana Grayum, Ann. Missouri Bot. Gard. 73: 464. 1986. Terrestrial; stems basally decumbent to erect, 5-22+ cm long; plants with milky sap. Leaves spiraled. Petioles 35-83 cm, never peltately attached, lacking a geniculum. Leaf-blades pedately compound, with 5-9 leaflets; medial leaflet 17-43 × 5.8-20 cm, narrowly to broadly elliptic. Infls. to 5 or 6 per leaf axil. Peduncles 13-48 cm. Spathe narrow (4.5-9 mm broad), the tube green externally, purplish within; lamina white to cream. Spadix 3.9-6.1 cm, with female region usually adnate to spathe in basal half; medial sterile zone present, but not distal sterile appendage. Fls. unisexual, naked; male fls. with 3-5 stamens connate in synandria; sterile male fls. with subprismatic, flat-topped synandrodia; female fls. with thin, spreading style containing orange chromoplasts; ovary ca. 3- or 4-locular; ovules few per locule, on axile or intrusive parietal placentae. Frs. white, 15-25-seeded. Wet forests, 250-1500 m; Atl. slope and near Continental Divide, Cords. Tilarán (Monteverde, R.B. Brenes), Central (Volcán Barva), and Talamanca. Fl. Oct., Nov. CR to NW Col. (Haber & Ivey 10403, INB) The combination of terrestrial, non-scandent habit, elongate (non-cormose) stems, and pedately compound leaf-blades is unique among CR Araceae. This sp. is very rare and local in CR, where it is known from just five collections. CR material belongs to subsp. croatiana, of CR and Pan. Colocasia Engler, A. & K. Krause. 1920. Colocasioideae. In A. Engler (ed.), Das Pflanzenreich IV.23.E (Heft 71): 3-132. Engelmann, Berlin. Ca. 8 spp., trop. and subtrop. Asia; 1 sp. in CR. Colocasia esculenta (L.) Schott, in Schott & Endl., Melet. bot. 18. 1832. Arum esculentum L., Sp. pl. 965. 1753; C. antiquorum Schott. Malanga, Ñampí. Terrestrial; stems cormose, to ca. 6 cm diam.; plants with reddish sap. Leaves spiraled. Petioles ca. 30-100 cm, peltately attached, lacking a geniculum. Leaf-blades simple, 19-85 × 12-70 cm, ovate-cordate to sagittate, usually with purplish blotch adaxially at petiole insertion, ± glaucous below. Infls. 1 or 2 {check!!} per leaf axil. Peduncles ca. 10-50 cm. Spathe tube greenish externally (sometimes tinged purplish), and also within; lamina pale yellowish, abscising after anthesis. Spadix ca. 10-30 cm; female region greenish; fertile and sterile male regions cream-yellowish; distal sterile appendage present, ca. 4.5-6.5 cm. Fls. unisexual, naked. Male fls. with 3-6 stamens connate in syandria; sterile male fls. with ± elongate synandrodia; female fls. with style lacking or short; stigma depressed-capitate, briefly 3-5-sulcate; ovary unilocular; ovules few-numerous , on parietal placentae. Frs. greenish, numerous -seeded. Humid regions, 0-1500+ m; commonly cult. for edible corms or ornamental foliage, occasionally escaping and may persist. Fl. Aug., Oct. Native to SE Asia or the Indo-Pac. region. (Grayum et al. 8742, MO) This well known sp. is usually easily recognized by its cormose habit and peltate leaf-blades, typically plain green except for a small purplish adaxial blotch over the petiole insertion; ornamental cultivars may have the leaf-blades heavily blotched or otherwise marked with purplish (Grayum et al. 11228; CR, INB, MO). Compare especially with Caladium bicolor (which see), as well as Alocasia and Xanthosoma spp. The corms of Colocasia esculenta are regularly available in CR markets, and the young leaf-blades are also edible. Dieffenbachia Lotería, sahinillo Engler, A. 1915. Anubiadeae, Aglaonemateae, Dieffenbachieae, Zantedeschieae, Typhonodoreae, Peltandreae. In A. Engler (ed.), Das Pflanzenreich IV.23.Bc (Heft 64): 1-78. Engelmann, Berlin. Ca. 50 spp., throughout the New World tropics; 13 spp. in CR. Terrestrial; stems terete, subrhizomatous or decumbent to erect, usually with some milky sap. Leaves spiraled. Petioles never peltately attached, without a geniculum. Leaf-blades simple, lanceolate to elliptical or ovate, often variegated or otherwise marked, the margins entire. Infls. 1-numerous per leaf axil; spathe with basal tube and distal lamina, uniformly green to greenish cream, persistent and usually becoming orange in fr.; spadix with separate male and female regions (the latter largely adnate to spathe), with brief medial sterile zone but no distal sterile appendage. Fls. unisexual, naked; male fls. with 4 or 5 stamens connate in synandria; sterile male fls. with staminodia distinct or connate; female fls. with 3-5 distinct or basally connate, ± clavate staminodia; style lacking; stigma 2- or 3-lobed; ovary 2- or 3-locular; ovules 1 per locule, borne at base of axile placentae. Frs. orange to red, 1-3-seeded. Seeds without endosperm. Dieffenbachia spp. are characterized by their terrestrial, caulescent habit, usually non-cordate leaf-blades, milky sap, and often vile-smelling foliage. The ± clavate staminodia subtending each pistil are also diagnostic. This genus is a taxonomic quagmire and has not been recently revised. Most spp. are di- or polymorphic for leaf-blade markings, a character upon which many taxa have been primarily based. The spp. appear to hybridize readily, and putative hybrids are often encountered in the field. The present treatment accounts for virtually all CR taxa, but many names are provisional, and with incomplete distribution data outside CR. Dieffenbachia is an important genus horticulturally due to the often ornately patterned leaf-blades. Several hybrids or selections of unresolved taxonomic identity are cultivated for ornament in CR and throughout the world. The Asian genus Aglaonema is often confused with Dieffenbachia, and has the same horticultural values. It differs in lacking milky sap and a medial sterile spadix zone, in having distinct stamens, and in lacking staminodia in the female fls. Dieffenbachia leopoldii W. Bull ex Mast. was reported from CR by Standley (1937), who indicated that its type had been collected "at Siquirres". In fact, it was collected in Col., according to the type specimen. 1 Petiole sheath involute, extending to base of leaf-blade and usually prolonged beyond it. 2 Leaf-blades rarely > 45 cm long or > 20 cm wide, usually cordulate at base, subcoriaceous, matte to glossy above, ± bullate, often variegated or with pale midrib; Atl. slope...D. tonduzii 2' Larger leaf-blades regularly to > 45 cm long and > 20 cm wide, cuneate at base, coriaceous, usually glossy above, plane, uniformly green; Pac. slope...D. sp. A 1' Petiole sheath erect to involute, ending short of blade base (except rarely on upper leaves). 3 Petiole beyond sheath ± triangular in section, sharply keeled to ridged abaxially, the margins thickly winged; Golfo Dulce region and lower Valle de El General...D. aurantiaca 3' Petiole beyond sheath subterete, rounded abaxially, with margins rounded to acute (not winged). 4 Leaf-blades with midrib and primary lateral veins densely puberulent with whitish hairs abaxially; rare sp. of Atl. lowlands...D. beachiana 4' Leaf-blades with midrib and primary lateral veins glabrous to minutely granular abaxially. 5 Petiole sheath decurrent distally; Atl. lowlands. 6 Stems to 1+ m tall, the leaves well distributed along their length; leaf-blades usually cordate to subcordate at base, usually flecked with cream...D. grayumiana 6' Stems < 1 m tall or, if taller, the leaves closely approximate with the petiole bases often overlapping; leaf-blades cuneate to rounded or truncate at base, plain green or (D. sp. B) occasionally variegated. 7 Petioles 7-25 cm, the unsheathed portion 1-7 cm; leaf-blades 9-28 cm long; peduncles 5-11 cm; spadix at anthesis 6.5-12.5 cm...D. hammelii 7' Petioles (15.5-)21.5-63 cm, the unsheathed portion (5.5-)12.5-25 cm; leaf-blades (12-)18.5-68 cm long; peduncles 7-30 cm; spadix at anthesis 9-25 cm. 8 Petioles drying yellowish to dark green and matte; leaf-blades ca. (12-)18-43 cm wide; widespread and locally abundant...D. longispatha 8' Petioles drying yellowish brown and appearing varnished; leaf-blades ca. 6-22 cm wide; very rare and local...D. sp. B 5' Petiole sheath (at least on one side) rounded to auriculate distally; widespread. 9 Leaf-blades lanceolate to narrowly or broadly elliptic, matte to weakly glossy above, with 18-37 primary lateral veins per side; plants with fetid odor; Golfo Dulce region...D. sp. C 9' Leaf-blades variously shaped, matte to glossy above, with 4-18 primary lateral veins per side; plants lacking fetid odor; widespread. 10 Spadix with medial sterile region, the fertile male and female regions separated by naked spadix axis. 11 Plants to 0.5+ m tall; leaf-blades to > 25 cm long or > 12 cm wide, usually elliptic (widest near middle), narrowly cuneate to rounded at base, coriaceous, glossy above, with 9-18 primary lateral veins per side; 0-500(-700) m...D. cocinna 11' Plants usually < 0.5 m tall; leaf-blades < 25 cm long and < 12 cm wide, ovate to elliptic (widest at base or middle), narrowly cuneate to subcordate at base, thinly coriaceous to subcoriaceous, matte to weakly glossy above, with 4-11 primary lateral veins per side; 0-1400 m...D. oerstedii 10' Spadix lacking medial sterile region, the fertile male and female regions abutting or virtually so. 12 Stems > 1 cm thick; leaf-blades minutely cordulate at petiole apex, without basal lobes; primary lateral veins departing midrib at < 90ƒ angle; Pac. slope (Osa Pen.)...D. sp. D 12' Stems < 1 cm thick; leaf-blades distinctly cordulate at base, with small basal lobes; primary lateral veins departing midrib at > 90ƒ angle; Atl. slope (Sixaola region)...D. sp. E Dieffenbachia aurantiaca Engl., Anales Inst. Fis.-Geogr. Nac. Costa Rica 9: 209. 1898. Stems often decumbent at base, to 2+ m tall and 5-7 cm wide. Petioles 11-32 cm, with sheaths rounded-auriculate distally; unsheathed portion 0.5-12 cm, acutely keeled to winged abaxially, with margins thickly winged. Leaf-blades 31-57 × 11.5-27 cm, ± oblong-elliptic, rounded to truncate or subcordate at base, ± coriaceous, weakly glossy above, plain green or (occasionally) variegated, with 8-19 primary lateral veins per side. Peduncles ca. 10-16(-19) cm. Spadix ca. 16-20 cm. Wet forests and swampy sites, 0-800 m; S Pac. slope (Valle de El General, Golfo Dulce region). Fl. May, Aug., Dec. CR and extreme W Pan. (Punta Burica). (Grayum & Herrera 9139; CR, MO) This sp. comprises coarse, vile-smelling plants, distinctive in life by virtue of their thickly winged petioles, triangular in cross-section. These features are usually not appreciable on herbarium specimens, and may not be noted on labels. Certain grossly similar collections from drier, more northern sites on the Pac. slope of CR [e.g., Gómez 19572 (MO), from near Atenas; Wilbur et al. 15861 (DUKE), from the lower part of the road to Monteverde] likely represent a different sp., perhaps the poorly understood D. wendlandii Schott (the type of which is from El Salv.). Dieffenbachia beachiana Croat & Grayum, in Croat, Novon 9: 491. 1999. Stems to ca. 1 m tall and 3.5 cm wide. Petioles 17-46 cm, ± roughened, with sheaths decurrent distally; unsheathed portion 10-29 cm, rounded abaxially, with margins obtuse to acute. Leaf-blades 17-41 × 6.5-15 cm, narrowly elliptic to lanceolate, cuneate to rounded or truncate at base, thinly coriaceous to subcoriaceous and ± quilted, semiglossy above, plain dark green (in CR), with 23-36 primary lateral veins per side departing midrib at ca. 90ƒ angle, the midrib and primary lateral veins puberulent below with thick, whitish hairs, the margins finely crispate. Peduncles ca. 9-12 cm. Spadix 10-15 cm. Wet forests, 40-800+ m; Atl. slope Cords. Central (to P.N. Tortuguero) and Talamanca. Fl. Jan., Apr., Nov. CR and W Pan. (Robles 1234; CR, MO) This is the most distinctive CR Dieffenbachia sp. by virtue of its abaxially pubescent leaf veins. Though all CR collections have plain green leaf-blades, some Pan. populations have variegated foliage. This sp. is best known from the La Selva Biological Station. Dieffenbachia concinna Croat & Grayum, in Croat, Novon 9: 492. 1999. Stems to ca. 1 m tall and 4 cm wide. Petioles 8-37+ cm, with sheaths rounded distally; unsheathed portion 1-14 cm, rounded below, the margins obtuse to acute. Leaf-blades 17-36(-42) × 7-22(-25.1) cm, elliptic to ovate or broadly lanceolate, cuneate to rounded or subtruncate at base, subcoriaceous to coriaceous, semiglossy to glossy above, plain green or (rarely) variegated, with 9-18 primary lateral veins per side. Peduncles 2.5-16.5(-18) cm. Spadix 11-16 cm. Wet forests, 0-500(-700) m; entire Atl. slope, S Pac. slope (Golfo Dulce region, Punta Burica). Fl. Mar., Apr., Aug.-Oct. ENDEMIC. (Grayum et al. 3982; CR, MO) Dieffenbachia concinna comprises handsome plants, most frequently collected in the Pac. lowlands. It somewhat resembles D. oerstedii (see key, couplet 11), but differs in its somewhat larger size, glossier stems, petioles, and leaf-blades, and more coriaceous leaf-blades with more numerous primary lateral veins. Though herbarium specimens are occasionaly difficult to place, the two spp. are sharply distinct at sites where they co-occur (e.g., E.B. La Selva). Dieffenbachia grayumiana Croat, Novon 9: 494. 1999. Stems to ca. 1 m tall and 3 cm wide. Petioles ca. 32-59 cm, with sheaths decurrent distally; unsheathed portion ca. 13-33 cm, subterete (obscurely flattened above distally). Leaf-blades ca. 28-50 × 12.5-25 cm, elliptical to lance-ovate or oblong ovate, rounded or subtruncate to (usually) shallowly cordate at base, thinly coriaceous to subcoriaceous, semiglossy to glossy above, sometimes ± bullate, plain green to (usually) variegated, with ca. 10-22 primary lateral veins per side. Peduncles ca. 5.5-16 cm. Spadix ca. 14-27 cm. Wet forests, 0-500(-1300) m; Atl. slope Cords. Tilarán and Central (to R.N.F.S. Barra del Colorado). Fl. Apr. CR and W Pan. (Grayum 9773; INB, MO) This rare sp. is characterized by its usually variegated, cordate-based leaf-blades uniformly distributed (the petiole bases not overlapping) along the relatively tall stems, and elongate infls. It is best known from the La Selva Biological Station, where it is found mostly in light gaps and disturbed sites in primary forest. Dieffenbachia hammelii Croat & Grayum, in Croat, Novon 9: 496. 1999. Stems decumbent at base, to ca. 0.5 m tall and 2 cm wide. Petioles 7-25 cm, with sheaths decurrent distally; unsheathed portion 1-7 cm, rounded abaxially, the margins acute. Leaf-blades 9-28 × 2.5-13.5 cm, narrowly to broadly elliptic or oblanceolate, narrowly to broadly cuneate at base, subcoriaceous, weakly glossy to semiglossy above, plain green, with 9-17 primary lateral veins per side. Peduncles 5-11 cm. Spadix 6.5-12.5 cm. Wet forests and swampy sites, 0-100(-1000?) m; Atl. slope, Llanuras de Tortuguero and Sarapiquí (and Cord. Tilarán?). Fl. Mar.-May. SE Nic. and CR. (Grayum et al. 9744; CR, MO) This is a rather nondescript sp., best known from the La Selva Biological Station. It is characterized by its subrhizomatous habit, distally decurrent petiole sheaths, and generally smallish, plain green leaf-blades. In many respects, D. hammelii resembles the rare D. sp. B, but the latter comprises generally larger plants with highly glossy petioles. Hammel et al. 15130 (MO), from 1000 m elevation in the Monteverde region, perhaps belongs to this sp. Dieffenbachia longispatha Engl. & K. Krause, Pflanzenr. IV.23DC (Heft 64): 44. 1915. Stems often decumbent at base, to ca. 1.5 m tall and 6.5(-12?) cm wide. Petioles (21-)31-63 cm, with sheaths decurrent distally; unsheathed portion (11-)13-25 cm, rounded abaxially, the margins rounded to obtuse. Leaf-blades 32-68 × (12-)18-43 cm, ovate to broadly (rarely narrowly) elliptic, broadly cuneate to rounded, truncate or (rarely) subcordate at base, coriaceous, glossy above, usually plain green, with 13-22 primary lateral veins per side. Peduncles 10-30 cm. Spadix 13.5-25 cm. Wet (often riparian) forests, 0-800(-1500?) m; entire Atl. slope. Fl. Jul.-Sep. SE Nic. to Pan., and possibly Col. (Grayum 9844; CR, MO) This sp. is easily recognized by its large size, decurrent petiole sheaths ending well short of the leaf-blade base, and thick, glossy leaf-blades. It is perhaps most similar to the very rare D. sp. B (see key, couplet 8). The plants often grow in dense stands, and emit a particularly foul odor when cut or bruised. Although D. longispatha is not definitely known from the Pac. slope, Croat 67700 (MO), from the head of Golfo Dulce, may represent this sp. Costa Rican material of D. longispatha is apparently separable into two varieties, as yet undescribed. Dieffenbachia oerstedii Schott, Oesterr. Bot. Z. 8: 179. 1858 (as 'oerstedtii'). D. seguine sensu Standl. (1937), non (Jacq.) Schott. Stems to ca. 0.75 m tall and 2 cm wide. Petioles 4-20 cm, with sheaths asymmetrically rounded-auriculate distally; unsheathed portion 0.5-12 cm, rounded abaxially, the margins obtuse to acute. Leaf-blades 7-26 × 1.5-13 cm, ovate to lanceolate or (rarely) oblanceolate, broadly cuneate to rounded, truncate or shallowly cordate at base, thinly coriaceous to subcoriaceous, matte to weakly glossy above, plain green to variegated or with pale midrib, with 4-11 primary lateral veins per side. Peduncles 3.5-12 cm. Spadix 7-12.5(-17) cm. Wet and moist forests, 0-1400 m; throughout. Fl. Feb., Apr.-Oct. S Mex. (Ver.) to W cent. Pan. (and perhaps elsewhere). (Grayum & Sleeper 6100; CR, MO) Dieffenbachia oerstedii is extremely variable in characters such as leaf-blade shape and markings; at least as many as three distinct pattern types may be occur within a single population. Nonetheless, this sp. is generally easily recognized by its small size, distally auriculate petiole sheaths ending well short of the leaf-blade base, and usually matte, often subcordate-based leaf-blades with comparatively few primary lateral veins. This is, both geographically and ecologically, the most wide-ranging sp. of Dieffenbachia in CR. Dieffenbachia tonduzii Croat & Grayum, in Croat, Novon 9: 497. 1999. D. pittieri sensu Standl. (1937), non Engl. & K. Krause. Stems to ca. 1 m tall and 4 cm wide. Petioles 7-24 cm, with sheaths involute and auriculate-prolonged distally; unsheathed portion obsolete or (rarely) to ca. 1 cm. Leaf-blades 18-43(-55) × 6.4-22(-27) cm, narrowly ovate to narrowly or broadly elliptic or (rarely) oblanceolate, broadly cuneate to rounded, cordulate, or shallowly cordate at base, thinly coriaceous to subcoriaceous, matte to glossy above, plain green to variegated or with pale midrib, with 17-39+ primary lateral veins per side. Peduncles 6-15 cm. Spadix 13-25 cm. Wet forests, 0-1400 m; entire Atl. slope. Fl. Apr.-Aug., Nov. SE Nic. to Pac. Ecua. (Grayum 8638; CR, MO) This common sp. is usually easily identified by its fully sheathed petioles and usually cordulate-based leaf-blades with numerous primary lateral veins. It may only be confused with the much rarer D. sp. A (see key, couplet 2), restricted to the Pac. slope. Dieffenbachia sp. A Stems decumbent at base, to ca. 1 m tall and 6 cm wide. Petioles 8-25 cm, with sheaths involute and asymmetrically auriculate-prolonged apically; unsheathed portion obsolete to ca. 0.5 cm. Leaf-blades 32-60 × 10-26 cm, narrowly to broadly elliptic or (rarely) oblanceolate, cuneate at base, subcoriaceous to coriaceous, semiglossy to highly glossy above, plain green, with ca. 14-26 primary lateral veins per side. Peduncles 8.5-18 cm. Spadix ca. 15-17 cm. Wet forests, 0-1000 m; Pac. slope from R.B. Carara and Puriscal region to San Isidro de El General/Dominical transect. Fl. May, Jul., Aug., Nov. ENDEMIC. (Grayum 8638; CR, MO) This and D. tonduzii are the only CR Dieffenbachia spp. in which the petiole sheath regularly extends to the leaf-blade base (and beyond). Dieffenbachia sp. A may be distinguished from the latter sp. by its Pac. slope habitat and thicker, glossier, differently shaped leaf-blades (see key, couplet 2). Herbarium material of D. sp. A bears a strong superficial resemblance to D. sp. B of the Atl. slope, but the latter sp. has longer, glossier petioles sheathed only in the proximal 1/3-2/3. Dieffenbachia sp. B Stems ca. 0.5-1(-1.5?) m tall and 1.5-3(-7) cm wide. Petioles (15.5-)21.5-48 cm, with sheaths decurrent distally; unsheathed portion (5.5-)12.5-22.5 cm, subterete or ± flattened or sulcate adaxially. Leaf-blades 18.5-57 × 6-21.8 cm, narrowly to broadly elliptic (and ± falcate) to oblanceolate or obovate (rarely, oblong or subovate), narrowly cuneate to broadly rounded at base, thinly coriaceous to (mostly) subcoriaceous to coriaceous, semiglossy to glossy above, matte and ± paler below, plain green to variegated or with the midrib paler, with ca. (8-)12-28+ primary lateral veins per side. Peduncles 7-28 cm. Spadix ca. 9-21.5 cm. Wet forests, 50-100 m; S Atl. slope (vic. Bribrí). Fl. Jun.-Sep. (Pan.). CR to Pac. Col. (Croat 43217, MO) Dieffenbachia sp. B is best characterized by its highly glossy petioles (with a varnished appearance when dried), sheathed only in the proximal 1/3-2/3, and subcoriaceous leaf-blades with rather numerous primary lateral veins. It most apt to be confused with the Atl. slope D. hammelii and D. longispatha (see key, couplets 7 and 8), but also resembles the Pac. slope D. sp. A and D. sp. C (see under those entries). This is a very rare sp. in CR, known by a single, sterile, juvenile collection. It is much better known from Pan., where it ascends to at least 1100 m elevation. Dieffenbachia sp. C Stems to ca. 1 m tall and 3.5 cm wide. Petioles 13-48 cm, with sheaths ± rounded distally; unsheathed portion 5.5-28 cm, rounded abaxially, with margins obtuse to acute. Leaf-blades 20-40 × 5-15.5 cm, lanceolate to narrowly or broadly elliptic, narrowly cuneate to rounded or truncate at base, thinly coriaceous to subcoriaceous, matte to weakly glossy above, plain green to variegated, with 18-37 primary lateral veins per side. Peduncles ca. 5-18 cm. Spadix 9-12 cm. Wet forests and swampy sites, 0-500(-1000) m; Pac. slope S from Dominical vic. Fl. Jan., Nov., Dec. ENDEMIC. (Grayum & Herrera 9236; CR, MO) This sp. is recognized by its ± dull, usually narrow leaf-blades with numerous primary lateral veins, and Pac. lowland habitat. It rather resembles the Atl. slope D. sp. B, which differs in its highly glossy petioles with the sheath distally decurrent. Dieffenbachia sp. D Stems to ca. 1 m tall and 1.5 cm wide (dried). Petioles ca. 8-14 cm, with sheaths auriculate distally; unsheathed portion ca. 1.8-4.3 cm. Leaf-blades ca. 18-25 × 5.5-10 cm, lanceolate, cuneate to rounded or truncate at base, potentially variegated, with ca. 10-15 primary lateral veins per side. Peduncles ca. 3-5 cm. Spadix ca. 10-11 cm. Wet forests, 15-30 m; S Pac. slope (Osa Pen.). Fl. Sep. CR to W Col. (Kennedy 1594, MO) This sp. and D. sp. E (see key, couplet 12) are unique among CR Dieffenbachia spp. in virtually lacking a medial sterile zone on the spadix. Dieffenbachia sp. D has been collected just once in CR, from ca. 4 km SW of Rincón de Osa. Dieffenbachia sp. E Stems to ca. 1 m tall and 1.7 cm wide. Petioles ca. 5.5-9 cm, with sheaths auriculate-prolonged distally; unsheathed portion ca. 2-5.5 cm, rounded below, the margins obtuse. Leaf-blades ca. 9-20 × 3-7 cm, narrowly to broadly oblong-elliptic, cordulate at base, subcoriaceous, glossy above, plain green (in CR), with ca. 9-15 primary lateral veins per side, departing midrib at 90ƒ angle or greater. Peduncles ca. 3-4 cm. Spadix ca. 7.5-11.5 cm. Wet forests, 20-40 m; S Atl. slope (Sixaola region). Fr. Nov. CR to E Pan. (Grayum et al. 4440; CR, MO) This very distinctive sp. has been collected in CR just twice, from essentially the same site. It is easily recognized by its smallish leaf-blades, cordulate at the base and with very unusual venation: the primary lateral veins are often directed away from the leaf apex in their proximal portions, then arch toward it distally. Some Pan. populations have variegated leaf-blades. Dracontium Zhu, G. 1995. Systematics of Dracontium L. (Araceae). Unpubl. Ph.D. dissertation, University of Missouri, St. Louis. Ca. 23 spp., throughout the New World tropics; 4 spp. in CR. Terrestrial; stems tuberous, usually with abundant apical tubercles; plants without milky sap. Leaves solitary. Petiole long, not peltately attached, lacking a geniculum, smooth to ± verrucose, mottled with brownish or purplish. Leaf-blades with three major divisions, each subdichotomously decompound. Infl. 1 (rarely 2) per axil; spathe erect, often cucullate, purplish externally, the margins not to broadly overlapping proximally; spadix uniform. Fls. bisexual, with perianth of 4-6(-7) distinct tepals; stamens (4-)5-17(-19), distinct; style as long as or longer than ovary; stigma capitate; ovary with 2-5(-7) locules; ovules 1 per locule, on axile placentae. Frs. 1-7-seeded. Seeds ± reniform to rounded, smooth to corrugate-verrucose. Uncommon or, at least, inconspicuous plants of primary forest, flowering only in light gaps or disturbed sites. They are easily recognized by their large, solitary leaves, with trichotomously decompound blades and petioles strikingly blotched with maroon. The peduncles are similarly marked, and the spathes are purplish and emit a foul odor. The CR spp. can generally be safely identified by locality alone, though D. pittieri and D. soconuscum occur in close proximity (but different habitats) within R.B. Carara. 1 Peduncle completely subterranean or not more than 10 cm above ground level; longest cataphyll reaching to base of or covering to 1/2 of the spathe; internal whitish area at base of spathe obsolete; dry or moist forests, Pac. slope (S to Río Grande de Tárcoles)... ...D. soconuscum 1' Peduncle 0.3-2.5 m long above ground level; longest cataphyll confined to base of peduncle, never reaching the spathe; internal whitish area at base of spathe conspicuous; wet forests, Atl. and Pac. slope (S from Río Grande de Tárcoles). 2 Peduncle 0.3-0.9 m long, < half as long as petiole, < 1.5× as long as spathe; spadix surpassing (ca. 2× as long as) whitish area at base of spathe; Atl. slope, S to near Siquirres...D. gigas 2' Peduncle 0.5-2.5 m long, > half as long as petiole, > 1.5× as long as spathe; spadix shorter than to barely equaling whitish area at base of spathe; Pac. slope, or Atl. slope S from Cahuita. 3 Laminar tissue on axes of three major leaf-blade divisions decurrent to near petiole apex; peduncle > 1.5 m long; spathe 30-70 cm long; Pac. slope...D. pittieri 3' Laminar tissue on axes of three major leaf-blade divisions not decurrent to near petiole apex, the axes naked in proximal 4-7+ cm; peduncle < 1.5 m long; spathe 17-35 cm long; Atl. slope...D. spruceanum Dracontium gigas (Seem.) Engl., in A. DC. & C. DC., Monogr. phan. 2: 284. 1879. Godwinia gigas Seem., J. Bot. 7: 313, t. 96, t. 97. 1869. Tuber to 20 cm diam., with few peripheral tubercles. Petiole to ca. 3.5 m long and 9.5 cm diam. at midpoint. Leaf-blade ca. 1.5-2.5 m diam. Peduncle 0.3-0.9 m long and 3.5-6 cm diam. at midpoint. Spathe 58-78 × 13-21 cm, cymbiform, cucullate, the margins broadly overlapping in lower 3/5-2/3; inner surface with basal, translucent, whitish area 4-7 cm high (shorter than spadix). Spadix 9-16 × 1.5-1.8 cm (dried), hidden from view, sessile or (rarely) stipitate. Frs. 1.8 × 1.5 cm, deep purplish or blackish. Wet forests, 0-700 m; Atl. slope S to vic. Siquirres. Fl. Jan., Dec. Cent. Nic. to CR. (Grayum 7992, CM, MO) As implied by the sp. epithet, Dracontium gigas is characterized by its immense size and massive infls. (the largest in the genus); the peduncles, however, are relatively short. It is almost indistinguishable vegetatively from the Pac. slope D. pittieri, but the latter has much longer peduncles and differs significantly in morphology and coloration of the spathe. Dracontium gigas is best known from the E.B. La Selva, where it often fls. in the Arboretum. Judging from the locality, the collection cited by Standley (1937) under the name Dracontium polyphyllum L. probably belongs to this sp. Dracontium pittieri Engl., Anales Inst. Fis.-Geogr. Nac. Costa Rica 9: 209. 1898. HOMBRÓN. Tuber 7-20 cm diam., with abundant peripheral tubercles. Petiole 1.8-3.5 m long, 5-8 cm diam. at midpoint. Leaf-blade ca. 1-2 m diam. Peduncle 1.5-2.5 m long, 4-6 cm diam. at midpoint. Spathe 30-70 × 8-20 cm, cymbiform, not cucullate, the margins scarcely overlapping at base; inner surface with basal, translucent, whitish area 5-17 cm high (longer than spadix). Spadix 4-9 × 1-1.5 cm (dried), easily visible, sessile. Frs. 0.6-1.2 × 0.9-1.3 cm, deep purplish. Wet forests, 0-1000 m; Pac. slope S from R.B. Carara. Fl. Feb., Apr., May, Jul.-Sep., Nov. ENDEMIC. (Quesada 259; CR, INB, MO) This is the only Dracontium sp. in the tropical wet forest of the Pac. slope. The leaves are immense, and very similar to those of D. gigas, from which D. pittieri differs in its much longer peduncles (the longest in the genus) and various infl. details. Dracontium soconuscum Matuda, Amer. Midl. Naturalist 41: 494. 1949. Dracontium dressleri Croat. Tuber 4-7 cm diam., with few peripheral tubercles. Petiole 1-1.5 m long, 3-5 cm diam. at midpoint. Leaf-blade ca. 0.75-1.2 m diam., with rare perforations. Peduncle 0.04-0.45 m long (mostly subterranean), 0.8-1.2 cm diam. at midpoint. Spathe 6-8(-10) × 3-4(-6) cm, non-cymbiform (i.e., constricted medially), cucullate, the margins broadly overlapping in lower half; inner surface with basal whitish area obsolete. Spadix 1-4 × 0.5-1 cm, easily visible, stipitate. Frs. 0.8-1.5 × 1-2 cm, orange-yellow on sides, burnt-orange apically, ± spongy. Dry or moist (often riparian) forests, 0-425 m; Pac. slope, scattered localities S to Río Grande de Tárcoles (Taboga; base of road to Monteverde; La Balsa de Atenas; Orotina; R.B. Carara). Fr. Jul., Aug. S Mex. (Chis.) to cent. Pan. (Grayum et al. 11108; CR, INB, MO) This is the smallest CR sp. of Dracontium, and the only one occurring in the drier regions of the Pac. slope. It has usually been found in shaded sites in riparian forest. The leaf architecture of D. soconuscum is somewhat distinctive in featuring small rounded or triangular segments alternating with acute- or acuminate-tipped larger ones. The short or obsolete peduncles are diagnostic. Dracontium spruceanum (Schott) G. Zhu, Novon 6: 308. 1996. Echidnium spruceanum Schott, Oesterr. Bot. Z. 8: 350. 1858; D. costaricense Engl. Tuber 4-18 cm diam., with abundant peripheral tubercles. Petiole ca. 1-2 m long, 1.2-4 cm diam. at midpoint. Leaf-blade ca. 0.9-1.5 m diam. Peduncle ca. 0.5-1.1 m long, 2-3.5 cm diam. at midpoint. Spathe 17-35 × 3-6 cm, non-cymbiform (constricted medially), non-cucullate, the margins broadly overlapping at the base; inner surface with basal, translucent, whitish area 4-8 cm high (longer than spadix). Spadix 3.4-6 × 0.7-1.1 cm (dried), hidden from view, stipitate. Frs. 0.5-0.7 × 0.7-1 cm, orange. Wet forests, 0-350 m; Atl. slope S from Cahuita vicinity. Fl. Jan., Feb., Jul., Nov. CR to Amaz. Perú, Suriname, and Braz. (Herrera 3189, CR) Dracontium spruceanum, the most widespread sp. in the genus, barely enters CR in the extreme SE corner. It resembles a scaled-down version of D. pittieri in terms of infl. proportions and coloration, but has more coarsely lobed leaf-blades, with the main axes naked toward the base (see key, couplet 3). The geographic range of D. spruceanum may abut that of D. gigas (with leaves like those of D. pittieri) in the region between Siquirres and Cahuita, from which no Dracontium collections are known. Heteropsis Engler, A. 1905. Pothoideae. In A. Engler (ed.), Das Pflanzenreich IV.23 (Heft 21): 1-330. Engelmann, Berlin. Ca. 13 spp., Nic. to Braz.; 1 sp. in CR. Heteropsis oblongifolia Kunth, Enum. pl. 3: 60. 1841. Ligneous canopy vines, rooted in the ground; plants lacking milky sap. Leaves distichous. Petioles 0.4-1.2 cm, broadly channeled above, without a geniculum. Leaf-blades simple, 10.5-21 × 2.7-7.2 cm, narrowly elliptic to oblong-lanceolate, the margins entire. Infls. solitary. Peduncle 0.9-2.2 cm. Spathe without a tube, erect and enclosing the spadix at anthesis, cream-yellow to greenish, promptly deciduous. Spadix uniform, 3.5-5.5 × 1-1.8 cm, sessile or stipitate to 2 mm, cream-yellow to light green. Fls. bisexual, naked; stamens 4, distinct; style absent; stigma depressed-convex; ovary unilocular (2-locular above); ovules 4, borne basally. Frs. orange-yellow to reddish, 1-4-seeded. Seeds large, black. Wet forests, 0-700+ m; entire Atl. slope, S Pac. slope (Golfo Dulce region). Fl. Jan., Mar.-May. NE Nic. to Bol. and Braz. (Grayum 2698; CR, DUKE, MO) Heteropsis is distinguished by its lianescent habit, slender, ligneous stems, and distichous, short-petiolate, simple, narrow, subcoriaceous leaf-blades. It does not resemble any other aroid vegetatively, but might be mistaken for a member of some other family, e.g., Annonaceae or Marcgraviaceae. The plants generally flower in the canopy, and fertile material is seldom seen. This sp. is valued in other parts of its range for binding and wickerwork. The application of the name (based on material from S Braz.) and the geographic range of the CR taxon are highly questionable. Homalomena Engler, A. 1912. Homalomeninae und Schismatoglottidinae. In A. Engler (ed.), Das Pflanzenreich IV.23 (Heft 55): 1-134. Engelmann, Berlin. Ca. 147 spp., mostly of trop. SE Asia; ca. 13 New World spp., from CR to Bol. and the Guianas, with 4 spp. in CR. Terrestrial; stems obsolete to erect; plants without milky sap, but usually with lingering, ± pungent, sweetish fragrance. Leaves spiraled. Petioles sometimes (elsewhere) peltately attached, not (or weakly) geniculate, glabrous to puberulent and/or muricate to aculeate (esp. toward base). Leaf-blades simple, elliptical or oblanceolate to cordate or sagittate, the margins entire. Infls. 1-several per axil, not secreting resin at anthesis (cf. Philodendron); spathe with proximal tube and distal lamina; spadix with separate male and female regions, with (rarely without) medial sterile zone but lacking distal sterile appendage. Fls. unisexual, naked; male fls. with 2-4(-6) distinct, prismatic stamens; female fls. with or without slender staminodia; style obsolete; stigma low-convex to slightly lobed; ovary apparently 2-4(5)-locular (actually unilocular); ovules 4-numerous per locule, borne on intrusive parietal (CR spp.) placentae. Frs. few- to (usually) many-seeded. Homalomena is extremely similar to Philodendron, from which it is separated by technical floral differences unsuitable for field or routine herbarium use. All spp. of Homalomena are terrestrial; ours are readily distinguished from the very few terrestrial CR Philodendron spp. (e.g., P. grandipes K. Krause) by their pubescent (H. picturata, H. wendlandii) or non-cordate (H. erythropus, H. hammelii) leaf-blades. The latter two spp. are sometimes mistaken for Dieffenbachia, but differ in their, spicy fragrance, lack of milky sap, absence of staminodia among the female fls., and whitish (rather than orange to red), many-seeded frs. 1 Leaf-blades attenuate to broadly cuneate or rounded at base, plain green or spotted to variegated, glabrous; plants (incl. herbarium specimens) redolent with strong, spicy aroma. 2 Plants acaulescent; petioles 9-27 cm long; leaf-blades spotted to variegated, 5.3-14.1 cm wide, widest at or above the middle, narrowly cuneate to attenuate at base, with ca. 9-18 primary lateral veins per side; peduncle 7.2-17 cm long; spadix at anthesis < 10 cm long; Pac. slope...H. erythropus 2' Plants acaulescent or with erect stems to at least 40 cm tall; petioles ca. 29-37 cm long; leaf-blades plain green, 12.5-18.7 cm wide, widest at or below the middle, broadly cuneate to rounded at base, with ca. 22-31 primary lateral veins per side; peduncle ca. 18-33.5 cm long; spadix at anthesis usually > 10 cm long; Atl. slope...H. hammelii 1' Leaf-blades truncate to deeply cordate or sagittate at base, plain green, pubescent below (at least along midrib and major veins); plants not strongly aromatic. 3 Leaf-blades narrowly elliptic to ovate, truncate to subcordate or auriculate at base, ca. 17-27.5 × 6.5-15.5 cm, with ca. 14-18 primary lateral veins per side; spadix ca. 5.2-6.5 cm, without staminodia among the female fls.; rare, Pac. slope...H. picturata 3' Leaf-blades deeply ovate-cordate to sagittate, ca. 30-67 × (15.5-)22.5-50 cm, with ca. 6-12 primary lateral veins per side; spadix ca. 11.5-18 cm, with capitate staminodia among the female fls.; occasional, both slopes...H. wendlandii Homalomena erythropus (Schott) Engl., Pflanzenr. IV.23 (Heft 55): 130. 1912. Philodendron erythropus Schott, Syn. Aroid. 76. 1856. Acaulescent. Petioles 9-27 cm, glabrous. Leaf-blades 15-38 × 5.3-14.1 cm, narrowly or broadly elliptic to obovate or oblanceolate, narrowly cuneate to attenuate at base, flecked to blotched with yellow-green or pale green, glabrous, with ca. 9-18 primary lateral veins per side. Peduncle 7.2-17 cm. Spadix (2.6-)6.2-9.7 cm. Wet forests, 0-350+ m; Pac. slope S from Z.P. La Cangreja. Fl. Mar.-Aug. CR to Amaz. Braz. (Grayum et al. 7545; CR, MO) The combination of an acaulescent, terrestrial habit, spicy fragrance, and variegated leaf-blades immediately distinguishes Homalomena erythropus from all other CR aroids. This sp. is typically found in deep shade on the banks of forest streams, often on red clay soil. The application of the name, based on Braz. material, is somewhat speculative. Homalomena hammelii Croat & Grayum, in Grayum, Phytologia 82: 37. 1997. Acaulescent or with erect stems to at least 40 cm tall and 2.5 cm wide. Petioles ca. 29-37 cm, glabrous. Leaf-blades 27.5-39 × 12.5-18.7 cm, broadly elliptic to narrowly ovate, broadly cuneate to rounded at base, plain green, glabrous, with ca. 22-31 primary lateral veins per side. Peduncle ca. 18-33.5 cm. Spadix (8.5-)12.6-12.8 cm. Wet forests, (50-)200-350+ m; Atl. slope Cord. Central (Volcán Barva). Fl. Mar., Jul. ENDEMIC. (Schatz & Fetcher 1047; CR, MO) Homalomena hammelii differs from H. erythropus in its larger dimensions, potentially caulescent habit, unpatterned leaf-blades, and Atl. slope habitat (see key, couplet 2, for additional details). It is known principally from along a single creek in P.N. Braulio Carrillo, where it grows abundantly in rocky, basaltic soil. A very small (ca. 3 plants) and perhaps ephemeral population is documented for E.B. La Selva. Homalomena picturata (Linden & André) Regel, Gartenflora 26: 33/Trudy Imp. S.-Petersburgsk. Bot. Sada 5: 269. 1877. Curmeria picturata Linden & André, in André, Ill. Hort. 20: 45, t. 121. 1873. Acaulescent, from a brief, orangish rhizome. Petioles 16-34 cm, ± densely and uniformly hirsute (but not asperous or aculeate). Leaf-blades 17-27.5 × 6.5-15.5 cm, narrowly elliptic to ovate, truncate to subcordate or auriculate at base, plain green (in CR), paler below, hirsutulous below along major veins, with ca. 14-18 primary lateral veins per side. Peduncle ca. 11-14 cm long. Spadix ca. 5.2-6.5 cm. Wet forests, 200-300 m; S Pac. slope (P.N. Piedras Blancas). Fl. Sep. CR to Bol., Fr. Guiana, Braz. (Croat & Hannon 79285; INB, MO) This mainly Sur Amer. sp. is very rare in CR, known from a single collection made in 1996. The first Mesoamerican record (Pan.) dates from 1994. Because of its pubescent foliage, Homalomena picturata could only be confused in CR with H. wendlandii, which occurs sympatrically but has larger and more deeply lobed leaf-blades with more numerous primary lateral veins (see key, couplet 3). Homalomena wendlandii Schott, Prodr. syst. Aroid. 308. 1860. Acaulescent. Petioles 33-142 cm, usually densely to sparsely puberulent (at least distally), sometimes asperulous to subaculeate (at least proximally). Leaf-blades 30-67 × (11.5-)22.5-50 cm, deeply ovate-cordate to sagittate, plain green, puberulent below on midrib and primary lateral veins (sometimes also on laminar surface and/or minor veins), with ca. 6-12 primary lateral veins per side. Peduncle 8-23 cm long. Spadix 11.5-18 cm. Wet forests, 0-650(-1000) m; Atl. slope Cords. Central (to R.N.F.S. Barra del Colorado and Llanura de Santa Clara) and Talamanca, Pac. slope S from Valle Central (vic. Alajuela) and R.B. Carara. Fl. Jan.-May. CR (and probably extr. SE Nic.) to Col. (Grayum et al. 4705; CR, MO) Homalomena wendlandii is sharply distinct from the other CR Homalomena spp. in its deeply cordate to sagittate leaf-blades. It might be mistaken for a Philodendron or Xanthosoma, but differs from the terrestrial CR Philodendron spp. in its pubescent leaves, and from Xanthosoma in lacking milky sap. Though widespread in CR, this sp. is usually not common, and is seldom collected in fertile condition. It is more weedy than our other spp., and is sometimes found in secondary forest or pasture edges. Monstera Madison, M. 1977. A revision of Monstera (Araceae). Contr. Gray Herb. 207: 1-100. Ca. 60 spp., from throughout the New World tropics; 22 spp. in CR. Terrestrial or epilithic plants to (much more frequently) appressed-climbing hemiepiphytes or canopy vines; stems never erect and self-supporting; plants lacking milky sap. Leaves distichous; some spp. heterophyllous (with abrupt ontogenetic change in leaf morphology). Petioles never peltately attached, with a geniculum. Leaf-blades simple, narrowly lanceolate to ovate-cordate, imperforate or perforate, the margins entire to pinnately lobed (sometimes very deeply). Infls. solitary in leaf (cataphyll) axils; spathe erect and enveloping spadix at anthesis, white to yellowish or pinkish, without a proximal tube, becoming broadly splayed and promptly deciduous; spadix ± uniform, but with some sterile fls. toward base. Fls. bisexual, naked; stamens 4, distinct; style thickened, about as long as ovary; stigma linear to capitate; ovary 2-locular; ovules 2 per locule, borne at the base of axile placentae. Frs. whitish to orangish, 1-3-seeded, the distal (stylar) portion dehiscent. Seeds 5-22 mm long, globose to oblong, lacking endosperm. Members of Monstera are distinct from most other CR Araceae in their scandent habit, distichous leaves with geniculate petioles, often pinnatifid and/or perforate leaf-blades, and naked, bisexual fls. Perforate leaf-blades occur in no other CR Araceae (except rarely in Dracontium). The only other araceous genera in CR with bisexual fls. lacking a perianth are the intimately related Heteropsis, Rhodospatha, and Stenospermation (see under those genera for distinguishing features). The juvenile plants of some Monstera spp. are very striking in having modified leaf-blades growing flattened against their support, the plants thus forming a very typical pattern on tree trunks in the understory. Despite having been recently revised (Madison, 1977), Monstera remains the most poorly understood CR aroid genus taxonomically. Useful morphological characters seem to be few, and intraspecific variation often considerable. Some spp. may flower precociously, when such features as internode length, petiolar sheathing, and leaf-blade size and morphology may differ greatly from typical adult conditions. The present treatment is still not wholly satisfactory; some collections, especially from montane localities, will not be identifiable (see discussions under M. epipremnoides, M. oreophila, M. standleyana). The total of 22 spp. here attributed to CR is probably conservative, even though it is the same as the total number of spp. in the genus according to Madison (1977). Epipremnum pinnatum (L.) Engl. cv. Aureum, of Australasian origin, is sometimes cultivated in CR and may occasionally be adventive. It resembles a Monstera in general aspect, but is readily identified by its yellow-variegated foliage. 1 Leaf-blades with primary lateral veins prominent, the secondary venation wholly reticulate; ± large-leaved plants, the blade usually perforate and/or pinnatifid (rarely imperforate and marginally entire). 2 Petiole sheath persistent, ending well short of geniculum on larger leaves; leaf-blades very thin, membranous, imperforate or perforate, the margins entire to irregularly few-pinnatifid; penduncle longer than spadix; ripe infrs. green; Pac. lowlands...M. membranacea 2' Petiole sheath deciduous, generally extending to within 1 cm of geniculum; lamina thinly coriaceous to coriaceous, usually perforate and with the margins regularly pinnatifid; peduncle shorter to longer than spadix; ripe infrs. cream-yellowish or sordid to brown. 3 Petiole equal to or longer than midrib of leaf-blade; leaf-blades ovate-cordate, < 1.5 × longer than wide; juvenile leaves not shingle-forming; peduncle longer than spadix...M. deliciosa 3' Petiole shorter than midrib of leaf-blade; leaf-blades lance-ovate to lance-elliptic or -oblong, > 1.5 × longer than wide; juvenile leaves shingle-forming; peduncle shorter to longer than spadix. 4 Stems of adult plants ± dorsiventrally compressed, longitudinally sulcate; perforations of larger leaf-blades in one series, open to midrib, with a thin, often filamentous laminar margin < 1 mm wide and often tearing; spathe usually pale pinkish within...M. filamentosa 4' Stems of adult plants subterete, roughened but not prominently sulcate; perforations of larger leaf-blades often in two series, usually not reaching midrib, with all laminar margins usually > 1 mm wide; spathe white or cream-yellowish to yellowish green within. 5 Leaf-blades broadly cuneate to rounded at base; peduncle at anthesis ca. 4-10 cm long, always shorter than spadix; spathe at anthesis pinkish externally; < 600(-800) m, mainly on Pac. slope...M. dubia 5' Leaf-blades cordate at base; peduncle at anthesis ca. 11-16 cm long, slightly shorter than to longer than spadix; spathe at anthesis yellowish green externally; > (600-)900 m, both slopes...M. punctulata 1' Leaf-blades with primary lateral veins prominent or obscure, the secondary lateral veins parallel (sometimes becoming reticulate toward margins), or else not differentiated from primary veins; leaf-blades small to large, imperforate or perforate, marginally entire to pinnatifid. 6 Juvenile leaves shingle-forming; leaf-blades of adult plants imperforate (perhaps very rarely perforate in M. pittieri); peduncle definitely shorter than spadix at anthesis. 7 Adult leaf-blades pinnate or pinnatifid (at very least, with one deep sinus extending virtually to the midrib on one side). 8 Lobes of adult blades 10-30 per side; spadix at anthesis ca. 15-25 cm long...M. tenuis 8' Lobes of adult blades 2-5 per side; spadix at anthesis ca. 5-18 cm long. 9 Loosely climbing vines; petioles of adult leaves < 20 cm long; leaf-blades mostly < 30 cm long; spadix at anthesis ca. 5-11 cm long...M. molinae 9' Appressed-climbing trunk epiphytes; petioles of adult leaves > 20 cm long; leaf-blades mostly > 30 cm long; spadix at anthesis ca. 11-18 cm long...M. spruceana 7' Adult leaf-blades with entire margins. 10 Coarse, appressed-climbing trunk epiphytes, the stems > 2 cm wide; petioles of adult leaves > 20 cm long; leaf-blades mostly > 25 cm long, with well differentiated primary lateral veins; spadix at anthesis ca. 11-18 cm long...M. spruceana 10' Slender, typically long-pendent canopy vines, the stems < 2 cm wide; petioles of adult leaves < 20 cm long; leaf-blades < 25 cm long, usually without well differentiated primary lateral veins; spadix at anthesis ca. 3.5-7 cm long. 11 Petioles of adult leaves ca. 1.5-6 cm long, the sheath terminating in a free ligule ca. 0.8-5.5+ cm long; leaf-blades consistently cordate or subcordate at base; pistils with curved, elongate, conical styles...M. tuberculata 11' Petioles of adult leaves mostly > 6 cm long, the sheath decurrent or scarcely prolonged distally; leaf-blades cuneate to rounded, truncate or (M. luteynii) subcordate basally; pistils truncate apically. 12 Leaf-blades ± ovate, < 2 × longer than wide, truncate to subcordate at base, drying greenish, with prominulous tertiary venation; peduncles at anthesis to > 5 cm long; stigma ca. 1 mm long; 600-900 m, Atl. slope...M. luteynii 12' Leaf-blades narrowly elliptical to ovate or oblong, often > 2× longer than wide, broadly cuneate to rounded or truncate at base, drying grayish or (rarely) brownish, with tertiary veins not prominulous; peduncles at anthesis to ca. 3.5 cm long; stigma ca. 2-3(-4) mm long; 0-800 m, both slopes...M. pittieri 6' Juvenile leaves not shingle-forming; leaf-blades of adult plants perforate or imperforate; peduncle almost invariably longer than spadix at (and usually after) anthesis. 13 Spathe peach-colored to salmon-pink internally...M. oreophila 13' Spathe white to cream or yellow internally, or else spathe color unknown. 14 Adult leaf-blades pinnately lobed (rarely with just a single sinus open to the margin on one side), sometimes also perforate. 15 Petioles, peduncles, cataphylls, young stems, and abaxial (outside) surface of spathe ± glaucous (the bloom rubbing off); petioles sheathed for < 3/4 their total length; spadix at anthesis with sterile basal fls. strongly and abruptly differentiated (± bowling-pin-shaped); appressed-climbing, understory trunk epiphytes of primary forest; 0-300(-700) m, Atl. slope...M. glaucescens 15' Petioles, peduncles, etc. not glaucous (or inconspicuously so, with bloom not rubbing off); petioles sheathed for > 3/4 their total length; spadices at anthesis with sterile basal fls. scarcely or ± gradually differentiated from fertile ones (not bowling-pin-shaped); habit and habitat various; widespread. 16 Petioles ± verrucate-roughened, especially toward base; leaf-blades thinly coriaceous to subcoriaceous, usually drying dark (reddish brown), with (10-)15-50+ primary lateral veins per side; lobes few (to 4 or 5 per side); 0-1100(-1400) m...M. buseyi 16' Petioles ± smooth; leaf-blades subcoriaceous to coriaceous, with 5-19(-25) primary lateral veins per side; lobes 2-9(-20) per side; 0-2000+ m. 17 Style conical to terete, ca. 1-1.5 mm long, conspicuously projecting especially in fr.; stigma ± circular in outline; foliage drying dark; (1000-)1300-1650+ m, Atl. slope and near Continental Divide...M. lentii 17' Style obsolete to laterally compressed, not conspicuously projecting; stigma ± linear in outline, vertical; foliage drying green to dark; 0-2000+ m, widespread. 18 Petiole sheath deciduous...[See discussions under M. epipremnoides and M. standleyana] 18' Petiole sheath persistent. 19 Leaf-blades with ca. (4-)6-20 lobes per side; primary lateral veins (9-)11-25 per side; (700-)1000-2000+ m, Pac. slope and near Continental Divide...M. epipremnoides 19' Leaf-blades with ca. 2-9 lobes per side; primary lateral veins ca. 5-19 per side; 0-800 m, both slopes. 20 Petioles green, concolorous or obscurely flecked or mottled, the sheath usually erect to revolute; leaf-blades drying green, with 2-5(-7) usually wide (often > 5 cm) lobes per side, these usually wider than the spaces between...M. dissecta 20' Petioles densely whitish flecked or stippled, the sheath involute; leaf-blades usually drying blackish, with 3-9 usually narrow (< 5 cm) lobes per side, these often narrower than the spaces between; Pac. slope...M. pinnatipartita 14' Adult leaf-blades with entire margins, imperforate or perforate (N.B.: larger perforations may closely approach the margins and occasionally tear through). 21 Petioles usually < 17 cm long, the sheath ultimately deciduous; leaf-blades drying blackish, with 4-6 primary lateral veins per side; spadix at anthesis orangish or peach-colored, 1 cm or less wide; < 100 m, extreme SE CR...M. obliqua 21' Petioles usually > 17 cm long, the sheath persistent to deciduous; leaf-blades drying green to grayish, reddish brown, or blackish, with 5-50+ primary lateral veins per side; spadix at anthesis white, cream or yellowish, usually > 1 cm wide; widespread. 22 Petiole sheath persistent or tardily deciduous, coarsely undulate for its entire length; leaf-blades drying grayish, with (11-)15-45 primary lateral veins per side; 0-100(-600) m, Atl. slope...M. costaricensis 22' Petiole sheath persistent to deciduous, ± plane (or undulate only on geniculum or toward base); leaf-blades drying green, reddish brown or blackish, with 5-50+ primary lateral veins per side; widespread. 23 Petioles ± verrucate-roughened, especially toward base; leaf-blades thinly coriaceous to subcoriaceous, usually drying dark (reddish brown), with (10-)15-50+ primary lateral veins per side...M. buseyi 23' Petioles smooth to verrucate-roughened toward base; leaf-blades thinly coriaceous to coriaceous, drying green to reddish brown or blackish, with 5-41 primary lateral veins per side. 24 Petiole sheath persistent; petioles smooth. 25 Petioles ca. 9-46 cm long; leaf-blades drying green, with 5-17 primary lateral veins per side; peduncles 8.5-25 cm long; spadix 1-2.7 cm wide; 0-700(-1150) m, both slopes...M. dissecta 25' Petioles ca. 39-89 cm long; leaf-blades drying blackish, with 12-25 primary lateral veins per side; peduncles ca. 17-40 cm long; spadix 2.8-4.2 cm wide; 0-1150 m, Atl. slope...M. standleyana 24' Petiole sheath ultimately deciduous; petioles often verrucate-roughened. 26 Leaf-blades subcoriaceous to coriaceous, drying reddish brown, with ca. 9-16 primary lateral veins per side, these often loop-connected (especially distally); spadix ca. (1.4-)1.7-2.5(-3) cm wide...[See discussion under M. standleyana] 26' Leaf-blades thinly coriaceous to subcoriaceous, drying yellow-green to grayish or reddish, with (6-)8-41 primary lateral veins per side, these usually not conspicuously loop-connected; spadix ca. 0.8-2.2 cm wide. 27 Leaf-blades (7.5-)17-48(-70) cm long, with (6-)8-18(-30+) primary lateral veins per side; peduncles 5.5-18(-24) cm long; spadix 0.8-1.7 cm wide; 0-1200(-1700+) m...M. adansonii 27' Leaf-blades 25-62(-77) cm long, with (10-)15-41 primary lateral veins per side; peduncles ca. 13-40 cm long; spadix 1.3-3(-3.5) cm wide; (800-)1300-2500 m...M. oreophila Monstera adansonii Schott, Wiener Z. Kunst 1830: 1028. 1830. Dracontium pertusum L., Sp. pl. 968. 1753, non M. pertusa (Roxb.) Schott (1830); M. friedrichsthalii Schott; M. pertusa (L.) de Vriese, nom. superfl. Piñanona, chirrivaca, ventanilla. Epiphytic vines, fertile ca. 1-5 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves (8-)16-40(-62) cm, ± smooth to densely and finely verrucate-roughened toward base, sheathed to near base of leaf-blade, the sheath deciduous. Leaf-blades (7.5-)17-48(-70) × (5-)7-31(-35) cm, ovate to lance-ovate or oblong, broadly cuneate to rounded, truncate, cordulate or (rarely) cordate at base (and usually ± inequilateral), thinly coriaceous to subcoriaceous, imperforate or (more frequently) perforate, with (6-)8-18(-30) primary lateral veins per side, the margins entire (sometimes appearing sparingly pinnatifid due to tearing). Peduncle 5.5-18(-24) cm. Spathe white within. Spadix 4.5-11(-15.5) × 0.8-1.7 cm. Infr. yellow-green to cream-yellowish. Dry, moist, and wet forests, 0-1200(-1700+) m; Atl. slope (mostly < 600 m) S to vic. Turrialba, entire Pac. slope. Fl. Jan.-Dec. Hond. to Perú, Guianas, Braz., Less. Ant. (Liesner 14251; CR, MO) Monstera adansonii is recognized by its deciduous petiole sheaths, imperforate or perforate (but not pinnatifid) leaf-blades usually ± inequilateral at the base, and slender spadices on long peduncles. It is most similar to M. buseyi, M. costaricensis, M. oreophila, and M. standleyana (see under those spp. for distinguishing characteristics). This is perhaps the commonest and most frequently collected CR Monstera, as well as the most ecologically versatile. It is one of the few Araceae found in the drier parts of the Guanacaste region. All Central American material of M. adansonii has been referred to var. laniata (Schott) Madison (Contr. Gray Herb. 207: 38. 1977; Tornelia laniata Schott, Oesterr. Bot. Z. 8: 179. 1858), which comprises more variability than many spp. Some collections from the Coto Brus region are especially unusual in having small, cordate leaf-blades, and may merit separate taxonomic recognition. Monstera adansonii is often cultivated as an ornamental in CR; selections with abundantly perforated leaf-blades are favored. Monstera buseyi Croat & Grayum, in Grayum, Phytologia 82: 38. 1997. Appressed-climbing trunk epiphytes, fertile ca. 1.5-3(-4) m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves (15.5-)20-60(-76) cm, verrucate-roughened especially toward base, sheathed to geniculum, the sheath erect to involute, often ± undulate especially distally, deciduous or ± persistent. Leaf-blades (20-)28-60(-83) × (8.5-)11-29(-43) cm, ovate to lance-ovate or elliptical, broadly cuneate to rounded, truncate or subcordate at base, thinly coriaceous to subcoriaceous, imperforate or (less frequently) perforate, with (10-)15-50+ primary lateral veins per side, the midrib and primary lateral veins sometimes verruculose to scaberulous abaxially, the margins entire to pinnately lobed (with up to 4-5 lobes per side). Peduncle 12-26 cm, sometimes verruculose. Spathe pale yellowish to white within. Spadix 5.5-11(-18) × 1-1.5(-2) cm. Infr. cream-yellowish. Wet forests, 0-1100(-1400+) m; Atl. slope and near Continental Divide, Cords. Guanacaste, Tilarán and Central [300-1100(-1400+) m], Pac. slope S from Río Grande de Tárcoles (0-800+ m). Fl. Jan.-Jul., Nov. CR and extr. SW Pan. (Punta Burica). (Grayum 6877, MO) Monstera buseyi is best characterized by its verrucate-roughened petioles and numerous primary lateral leaf veins. These features are shared with the Atl. slope M. costaricensis, which differs in having relatively shorter petioles and peduncles, and coarsely undulate petiole sheaths. Monstera buseyi is more likely to be confused with the widespread and sympatric M. adansonii, from which it differs in its reddish-brown-drying leaf-blades with more numerous primary lateral veins. The leaf-blades of M. buseyi are more often imperforate than perforate, while the reverse is true of M. adansonii. Furthermore, M. buseyi prefers generally more humid habitats than M. adansonii. Monstera costaricensis (Engl. & K. Krause) Croat & Grayum, Ann. Missouri Bot. Gard. 74: 659. 1987. Rhodospatha costaricensis Engl. & K. Krause, Pflanzenr. IV.23B (Heft 37): 95. 1908. Appressed-climbing trunk epiphytes, fertile ca. 2.5-4.5 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves (10.5-)17-30 cm, verrucate-roughened especially toward base, sheathed to base of blade, the sheath coarsely undulate throughout, persistent or ultimately deciduous. Leaf-blades (17.5-)27-73 × (8-)14-30 cm, narrowly ovate to lance-ovate, broadly cuneate to truncate at base, subcoriaceous, imperforate or perforate, with (11-)15-45 primary lateral veins per side, the margins entire. Peduncle (6.5-)10-16 cm. Spathe (apparently) white within. Spadix (5.2-)7.5-11.5 × 1.2-2 cm. Infr. color unknown. Wet (often swamp) forests, 0-100(-600) m; entire Atl. slope. Fl. Jan., Mar.-May, Aug., Oct. ENDEMIC. (Grayum & Robles 8523, MO) Monstera costaricensis is most similar to M. buseyi (see under that entry) and the sympatric M. adansonii, from which it differs in its generally larger, grayish-drying leaf-blades with more numerous primary lateral veins. The petiole sheaths of M. costaricensis are unique within the genus in being coarsely undulate throughout their length. Some material from the E.B. La Selva appears intermediate between this sp. and M. adansonii. Monstera deliciosa Liebm., Vidensk. Meddel. Dansk Naturhist. Foren. Kjøbenhavn 1849: 19. 1849. M. dilacerata sensu Standl. (1937), non (K. Koch & Sello) K. Koch. Chirrivaca. Terrestrial vines or robust, appressed-climbing, canopy epiphytes to ca. 30 m above ground, with long-pendent, corky-ridged roots. Juvenile leaves not shingle-forming. Petioles of adult leaves 23-83 cm, smooth, sheathed to geniculum (where sometimes undulate), the sheath deciduous. Leaf-blades 27-90 × 22-70 cm, ovate to suborbicular, cordate at base, subcoriaceous to coriaceous, perforate, with 6-10 primary lateral veins per side, the margins pinnatifid. Peduncle 7.5-16 cm. Spathe cream to pale pinkish within. Spadix ca. 6.8-10 × 1.4-2.4 cm. Infrs. cream-yellowish. Wet forests to seasonally dry oak forests, 400-2000+ m; Atl. slope Cords. Tilarán, Central, and Talamanca, Pac. slope (> 1200 m) Cord. Talamanca. Fl. Feb., Mar., May, Jul.-Sep., Nov. Mex. to Pan. (Herrera 3383, MO) Monstera deliciosa is easily recognized by its relatively long petioles (equal to or longer than the midrib of the leaf-blade), broadly cordate leaf-blades that are both pinnatifid and perforate, and peduncles longer than the spadix at anthesis. Plants growing at lower elevations tend to be very robust, canopy epiphytes, while those from higher elevations are much smaller and often virtually terrestrial. The coarser forms are commonly cultivated in CR and throughout the tropics, for ornament and (less frequently) for their edible infrs. Monstera dissecta (Schott) N. E. Br. ex Donn. Sm., Enum. pl. guatem. 5: 88. 1899. Tornelia dissecta Schott, Oesterr. Bot. Z. 8: 179. 1858. Appressed-climbing vines or trunk epiphytes, fertile ca. 1-4 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves (4-)9-46 cm, ± smooth, concolorous or obscurely flecked or mottled, sheathed to geniculum, the sheath erect to revolute (rarely involute), persistent. Leaf-blades (8-)14-53 × (3.7-)6-32 cm, ovate to elliptical or oblong, broadly cuneate to rounded or truncate at base, subcoriaceous to coriaceous, imperforate or (rarely) sparingly perforate, with 5-17 primary lateral veins per side the margins entire to (most frequently) pinnatifid [with 2-5(-7) lobes per side]. Peduncle 8.5-25 cm. Spathe cream-colored to pure white within. Spadix 5-16.5 × 1-2.7 cm. Infrs. cream to white. Wet forests, 0-700(-1150) m; entire Atl. slope, Pac. slope Cords. Guanacaste and Talamanca. Fl. Jan.-Sep., Nov., Dec. Bel. to W Pan. (Grayum & Jacobs 5319; CR, MO) This is one of just two Monstera spp. in the Atl. lowlands of CR with persistent petiole sheaths and leaf-blades becoming pinnatifid. The other, M. glaucescens, differs in its glaucous parts and less extensively sheathed petioles. Monstera dissecta is more similar to the allopatric M. epipremnoides, M. lentii, and M. pinnatipartita (see under those entries). Plants of Monstera dissecta may eventually become robust, appressed-climbing trunk epiphytes with very short internodes and strikingly distichous leaves, with pinnatifid blades with ± erect petiole sheaths. However, they may also flower as loosely scandent vines with long internodes, small, sometimes sparingly perforate, marginally entire or subentire leaf-blades, and splayed petiole sheaths. Such precociously flowering individuals may easily be taken for a different sp. The name Monstera dilacerata (K. Koch & Sello) K. Koch has been variously applied to CR material, but especially to M. dissecta, M. pinnatipartita, and allied spp. (e.g., by Madison, 1977); however, it has recently been established as a synonym of the Asian Epipremnum pinnatum (L.) Engl. (see Grayum, Phytologia 82: 41-42. 1997; Boyce, Blumea 43: 201, 205. 1998). Monstera dubia (Kunth) Engl. & K. Krause, Pflanzenr. IV.23B (Heft 37): 117. 1908. Marcgravia dubia Kunth, in Humb., Bonpl. & Kunth, Nov. gen. sp., Quarto ed. 7: 217; Folio ed. 7: 169. 1825. Appressed-climbing trunk epiphytes, fertile to at least 5 m above ground. Juvenile leaves shingle-forming, plain green. Petioles of adult leaves ca. 35-51 cm, ± roughened toward base, sheathed to geniculum, the sheath deciduous. Leaf-blades ca. 65-120 × 35-55 cm, narrowly ovate to elliptical or oblong, broadly cuneate to rounded or truncate at base, subcoriaceous or ± chartaceous, perforate, with ca. 12-21 primary lateral veins per side, the margins pinnatifid. Peduncle ca. 4-9 cm. Spathe white within, pinkish externally. Spadix ca. 7-12 × 1.5-2.5 cm. Infrs. pale yellow. Wet or moist forests, 0-100(-800) m; N Atl. slope (Llanura de San Carlos?), Pac. slope S from Río Grande de Tárcoles. Fl. Feb., Apr., Jul., Aug. SE Nic. to Ven. and Bol. (Grayum et al. 5962, MO) Monstera dubia is easily recognized by its large, drooping, coriaceous leaf-blades that are both perforate and pinnatifid, and virtual restriction (in CR) to the Pac. lowlands. It is most similar to the allopatric M. punctulata, a sp. of higher elevations (see key, couplet 5). A sterile, juvenile collection (Hammel & de Nevers 15309, MO) from 300 m elevation in the San Carlos region (Prov. Alajuela) probably represents this sp. In some parts of its range, M. dubia may flower with juvenile leaves. Monstera epipremnoides Engl., Bot. Jahrb. Syst. 37: 118. 1905. Trunk epiphytes, fertile to ca. 4-8 m above ground. Juvenile leaves unknown, presumably not shingle-forming. Petioles of adult leaves 25-50 cm, smooth, sheathed to geniculum, the sheath persistent. Leaf-blades (24-)31-55 × (11.5-)16-35 cm, narrowly ovate to elliptical, broadly cuneate to (more frequently) rounded or truncate at base, subcoriaceous, usually sparingly perforate, with ca. (9-)11-25 primary lateral veins per side, the margins pinnatifid [with ca. (4-)6-20 lobes per side]. Peduncle (11.5-)18-30 cm. Spathe white within. Spadix 6.5-12 × 1.4-2.5 cm. Infrs. white. Wet forests, (700-)1000-2000+ m; both slopes Cords. Guanacaste and Central, Pac. slope Cord. Talamanca, Cerros de Escazú, Cerro Caraigres, Cerro Turrubares. Fl. Jan., Mar.-May, Jul., Sep. ENDEMIC? (Davidse et al. 28341, MO) Monstera epipremnoides remains an imperfectly known entity. Included here are montane plants answering the description of M. dissecta, but with a tendency to have more frequently perforate leaf-blades with more numerous lobes, shorter spadices on longer peduncles, and more prominently elevated stigmas. The type of M. epipremnoides is from 1300 m near Santa María de Dota, and the specimen cited above is from a similar elevation on the Pac. slope of the Cord. Talamanca in the Coto Brus region; other ± typical specimens are: Jiménez & Quesada 1184 (INB, MO), from 1500 m on Cerro Turrubares; Herrera et al. 405 (MO), from 1000 m near Grecia in the Cord. Central; and C. Chávez 187 (INB, MO), from 700 m near Estación Pitilla, Cord. Guanacaste. Numerous collections from the Cord. Tilarán (e.g., Haber ex Bello C. 4274, MO) and some from the Cord. Central agree ± with the description of M. epipremnoides, but have deciduous petiole sheaths. These collections may represent a separate taxonomic entity or hybrids, or perhaps M. epipremnoides is simply variable in this regard. Monstera filamentosa Croat & Grayum, in Grayum, Phytologia 82: 43. 1997. Appressed-climbing trunk epiphytes, fertile ca. 3.5-5 m above ground, the stems ± dorsiventrally compressed and coarsely sulcate. Juvenile leaves shingle-forming. Petioles of adult leaves ca. 23-61 cm, ± smooth, sheathed to near geniculum, the sheath deciduous. Leaf-blades ca. 48-110 × 26-56 cm, narrowly elliptical to lance-oblong, broadly cuneate to rounded or subcordate at base, thinly coriaceous to subcoriaceous, perforate centrally via ± filamentous strands, the margins ± regularly and deeply pinnatifid [with (6-)9-15 lobes and 1(2) primary lateral veins per lobe]. Peduncle ca. 4.5-11 cm. Spathe whitish to (usually) pinkish within. Spadix 7-11 × 1.6-2.2 cm. Infr. color unknown. Wet forests, 0-500 m; Atl. slope Cords. Central (to R.N.F.S. Barra del Colorado) and Talamanca, S Pac. slope (Osa Pen.). Fl. Apr., Jul.-Sep. CR (and ostensibly extreme SE Nic.) to extreme NW Col. (Grayum & Hammel 5539; CR, MO) Monstera filamentosa is easily recognized by its ± flattened, sulcate stems and narrow, pinnate or pinnatifid leaf-blades, medially perforate via filamentous laminar strands. At or near anthesis, the usually pale pinkish internal spathe coloration is also helpful. The only other CR Monstera spp. with the latter feature are M. deliciosa and M. oreophila (M. dubia has externally pinkish spathes). Monstera glaucescens Croat & Grayum, in Grayum, Phytologia 82: 44. 1997. Appressed-climbing trunk epiphytes, fertile ca. 1-2.5 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves ca. 18-41 cm, ± smooth, glaucous, sheathed for ca. 1/2-3/4 their total length, the sheath erect, persistent. Leaf-blades ca. 25-47 × 15-33 cm, ovate to elliptical, broadly cuneate to rounded, truncate, or subcordate at base, subcoriaceous to coriaceous, imperforate, with 6-17 primary lateral veins per side, the margins ± deeply pinnatifid [with (2)3-5(-8) lobes per side]. Peduncle ca. 12-22 cm. Spathe white within. Spadix 5-9 × 1-1.7 cm. Infr. color unknown. Wet forests, 0-300(-700) m; entire Atl. slope. Fl. Jan.-May, Sep.-Nov. SE Nic. to E Pan. (Liesner et al. 15034; CR, MO) Monstera glaucescens is most similar to M. dissecta and the allopatric M. pinnatipartita, from both of which it is distinguished by its glaucous parts and comparatively short-sheathed petioles. As neither of these features is obvious on exsiccatae, herbarium material is less distinctive. The leaf-blades of M. glaucescens dry blackish, as those of M. pinnatipartita, but unlike those of the sympatric M. dissecta. Monstera lentii Croat & Grayum, in Grayum, Phytologia 82: 46. 1997. Appressed-climbing trunk epiphytes, fertile ca. 2-3(-8) m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves 22-56(-72) cm, ± smooth, sheathed to within ca. 1-4 cm of geniculum, the sheath erect to revolute, persistent (usually) or ± deciduous. Leaf-blades 28-60 × 17.5-41 cm, ovate to ± oblong, broadly cuneate to rounded or subcordate at base, subcoriaceous, often perforate, with 10-14(-16) primary lateral veins per side, the margins ± deeply pinnatifid [with 3-8 lobes per side]. Peduncle 7.5-25 cm. Spathe white to cream within. Spadix 5-12 × 1.3-2.3(-3.1) cm. Infrs. white. Wet forests, (1000-)1300-1650+ m; Atl. slope. and near Continental Divide, Cord. Tilarán and N Cord. Talamanca (P.N. Tapantí, Moravia de Chirripó, etc.). Fl. Feb.-Sep., Nov. CR and W Pan. (Liesner & Judziewicz 14549; CR, MO) Monstera lentii most resembles those other CR Monstera sp. with persistent petiole sheaths and pinnatifid leaf-blades, especially M. dissecta, M. epipremnoides, M. glaucescens, and M. pinnatipartita; its deeply pinnatifid, blackish drying leaf-blades especially recall the last-mentioned sp. Monstera lentii is the only sp. in this group occurring > 1000 m on the Atl. slope of the Cord. Talamanca. It is unique among all CR Monstera spp. in its conical or terete, projecting styles and capitate stigmas. Panamanian material tentatively referred to Monstera lentii, mainly from the La Fortuna region, seems to have consistently deciduous petiole sheaths. Monstera luteynii Madison, Contr. Gray Herb. 207: 89. 1977. Epiphytic vines to at least 7 m above ground, hanging from trees. Juvenile leaves unknown, presumably shingle-forming. Petioles of adult leaves ca. 8-13 cm, ± roughened toward base (dry), sheathed to geniculum, the sheath deciduous. Leaf-blades ca. 12-19.5 × 9-12.5 cm, ovate to broadly elliptical, rounded to truncate or subcordate at base, coriaceous, imperforate, with ca. 4-6 primary lateral veins per side, the margins entire. Peduncle ca. 3.5-5 cm. Spathe "white" (Lent 3889). Spadix ca. 6-8 × 1.8-2.1 cm. Infr. color unknown. Wet forests, 600-900 m; Atl. slope. Cords. Tilarán (La Balsa de San Ramón), Central (Laguna Hule), and Talamanca (Las Vueltas de Tucurrique, Tuis). Fl. Jun., Sep. ENDEMIC. (Bello & Villegas 1468, MO) Monstera luteynii is a rare and local sp., known only from the sites enumerated above. Among CR Monstera spp., only M. tuberculata and, especially, M. pittieri resemble it in habit and overall aspect (pendent, canopy vines with small, imperforate, marginally entire leaf-blades). Both of the last-mentioned spp. are at least potentially sympatric with M. luteynii (see key, couplets 11 and 12, for distinguishing characteristics). Monstera membranacea Madison, Contr. Gray Herb. 207: 55. 1977. Appressed-climbing trunk epiphytes, fertile ca. 2-4 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves ca. 29-63 cm, smooth, sheathed for ca. 3/5-4/5 their total length, the sheath persistent. Leaf-blades 25-51 × 15-28 cm, narrowly to broadly ovate or elliptical, subcordate to cordate at base, membranaceous, imperforate or perforate, with ca. 7-11 primary lateral veins per side, the margins entire to pinnatifid. Peduncle ca. 9-18 cm. Spathe cream-white to light yellowish within. Spadix 7-11 × 1.2-2.5 cm. Infrs. green. Wet forests, 0-800 m; Pac. slope S from Río Grande de Tárcoles. Fl. Jan., Feb., Apr., May, Jul., Aug. CR and extreme SW Pan. (Punta Burica). (Kernan 427; CR, MO) Monstera membranacea is a very distinctive and unusual sp. that is not confused with any other. No other CR Monstera sp. has such short-sheathed petioles except the very different M. glaucescens. Its Pac. lowland habitat and very thin, bright green leaf-blades with coarsely reticulate secondary venation also combine to distinguish M. membranacea. Monstera molinae Grayum, Phytologia 82: 48. 1997. Epiphytic vines on tree-trunks, or ascending to canopy. Juvenile leaves unknown, presumably shingle-forming. Petioles of adult leaves ca. 7.5-19 cm, smooth (dry), sheathed to near base of blade, the sheath deciduous. Leaf-blades ca. 10.5-33 × 8-27 cm, broadly ovate to elliptical, broadly cuneate to rounded or truncate at base, subcoriaceous, imperforate, with 4-8 primary lateral veins per side, the margins deeply pinnatifid (with 2-5 lobes on at least one side). Peduncle ca. 2.5-6 cm. Spathe creamy white within. Spadix 5-10 × 1.5-2.4 cm. Infr. color unknown. Wet forests, 0-1000+ m; Atl. slope and near Continental Divide, Cords. Guanacaste, Tilarán, and Central. Fl. Jan.-Mar., May, Nov. CR and cent. Pan. (El Copé). (Davidse et al. 23344, MO) Monstera molinae is grossly similar to M. luteynii, M. pittieri, and M. tuberculata, all loosely scandent, canopy vines with smallish leaves, but differs from all of these in having pinnatifid leaf-blades. It also bears a resemblance to M. spruceana, which may rarely (in CR) have pinnatifid leaf-blades, but plants of the latter sp. have a somewhat different (consistently appressed-climbing) growth habit and are larger in all of their parts (see key, couplet 9). Monstera obliqua Miq., Linnaea 18: 79. 1844. Epiphytic vines on trunks of understory trees, fertile ca. 2 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves ca. 9.5-16 cm, ± smooth, sheathed to geniculum, the sheath ultimately deciduous. Leaf-blades 14-23 × 4-8 cm, lanceolate to narrowly elliptical, cuneate at base, membranaceous to thinly coriaceous, imperforate to sparingly perforate, with 4-6 primary lateral veins per side, the margins entire. Peduncle 10-14.5 cm. Spathe "yellowish" (Barringer et al. 3489, MO). Spadix ca. 4.5 × 1 cm. Infrs. dull orange. Wet or moist forests, 0-100+ m; Atl. slope S Cord. Talamanca (Sixaola region, Bribrí, Alto Urén). Fl. Jul., Oct., Nov. CR to Bol., Guianas, Trinidad and Tobago, Braz. (Grayum et al. 4458; CR, MO) Monstera obliqua barely enters CR in the extreme SE corner of the country. It is easily recognized by its tenuous habit, simple, smallish, narrow, blackish drying leaf-blades, with few primary lateral veins, and, especially, by its orangish fruiting spadices. CR material more commonly has imperforate than perforate leaf-blades. The only other CR Monstera sp. with which M. obliqua might be confused is M. pittieri, but plants of the latter sp. generally climb into the canopy and have relatively much shorter peduncles. Monstera oreophila Madison, Contr. Gray Herb. 207: 54. 1977. Appressed-climbing trunk epiphytes, fertile ca. 1-4 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves ca. 28-70 cm, ± smooth to finely asperous, often finely costulate, sheathed to geniculum, the sheath ultimately deciduous. Leaf-blades ca. 26-62(-77) × 10-42 cm, ovate to lance-ovate, -oblong, or -elliptical, cuneate to rounded, truncate, or (rarely) cordulate at base, thinly coriaceous to subcoriaceous, perforate, with (11-)15-41 primary lateral veins per side, the margins entire (occasionally sparingly to regularly pinnatifid via tearing). Peduncle ca. 13-40 cm, sometimes finely asperous. Spathe peach-colored or salmon-pink within. Spadix ca. 7-15 × 1.3-2.2 cm. Infrs. cream-yellowish. Wet forests, (800-)1300-2200+ m; both slopes of all main cords., Montes del Aguacate, Cerros de Escazú. Fl. Jan.-Dec. CR and W Pan. (Herrera 5361; INB, MO) This is the only Monstera sp. with non-reticulate leaf venation and pinkish spathes. Unfortunately, spathes in Monstera are ephemeral and usually not present. Monstera oreophila is otherwise very similar to (and sometimes difficult to distinguish from) the widespread M. adansonii, from which it differs in its generally larger leaf-blades with more numerous primary lateral veins, and by its preference for primary forest at higher elevations (see key, couplet 27). The leaf-blades of M. oreophila tend to dry yellowish green, unlike those of M. adansonii and especially M. buseyi, which dry darker. Occasional specimens of M. oreophila with apparently pinnatifid (via marginal tearing) leaf-blades might be mistaken for M. epipremnoides, but the latter sp. has persistent petiole sheaths (and white spathes). Gereau & Taylor 3475 (INB, MO) is the only collection here attributed to M. oreophila from the Cord. Guanacaste, as well as the only such collection from below 1300 m. It is also unusual in having long, proportionately narrow leaf-blades with comparatively few and large perforations opening to the margins, and rather distant primary lateral veins. The combination of non-reticulate leaf venation and pinkish spathes suggests M. oreophila, but separate taxonomic recognition for this population is conceivable, pending additonal field work. Well-grown, mature specimens of Monstera oreophila have considerable ornamental appeal, even in vegetative condition, by virtue of their large, copiously perforate, heavily veined leaf-blades. Monstera pinnatipartita Schott, Oesterr. Bot. Wochenbl. 7: 197. 1857. M. dilacerata sensu Fl. BCI, Fl. Panama (pro parte), non (K. Koch & Sello) K. Koch. Appressed-climbing trunk epiphytes, fertile ca. 2.5-6(-15) m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves 20-52(-79) cm, smooth, heavily whitish speckled, sheathed to within ca. 3-7 cm of geniculum, the sheath ± involute, persistent. Leaf-blades 26-70 × 19-47 cm, ovate to elliptical, broadly cuneate to rounded or truncate at base, subcoriaceous to (rarely) coriaceous, imperforate or (rarely) with a few perforations, with ca. 6-19 primary lateral veins per side, the margins deeply pinnatifid (with 3-9 lobes per side). Peduncle 9-23(-32.5) cm. Spathe pure white within. Spadix 5.5-11.5(-14.5) × 1.1-1.7(-2.5) cm. Infrs. cream (frs. white). Wet or moist forests, 0-500(-800+) m; Pac. slope S from Río Grande de Tárcoles, and scattered sites N (S Nicoya Pen., vic. Barranca), Isla del Caño. Fl. Jan., Mar., Apr., Jun., Aug.-Dec. CR to Ecua. and Ven. (Herrera 4300; CR, MO) Monstera pinnatipartita is generally easily identified by its involute, persistent petiole sheaths, blackish drying leaf-blades deeply pinnatifid into narrow lobes, and Pac. lowland habitat. It is most similar to the allopatric M. glaucescens and M. lentii, both of which also have pinnatifid, blackish drying leaf-blades (see under those spp. for distinguishing features). Like many other Monstera spp., M. pinnatipartita may flower precociously with reduced, less divided leaf-blades. An extreme in this regard (if not a different sp. altogether) is J. F. Morales 3119 (INB), from ca. 300 m elevation in Z.P. La Cangreja, which has very small (to ca. 18 cm long), marginally entire leaf-blades. Monstera pittieri Engl., Bot Jahrb. Syst. 37: 116. 1905. Epiphytic vines climbing to at least 10 m, the fertile shoots pendent. Juvenile leaves shingle-forming. Petioles of adult leaves 7-13(-16) cm, smooth, sheathed to within ca. 1.5 cm of geniculum, the sheath ultimately deciduous. Leaf-blades 9-20(-25) × 4-8(-11) cm, broadly to narrowly ovate to elliptical, or oblong or lanceolate, broadly cuneate to rounded or truncate at base, subcoriaceous to coriaceous, imperforate or (Pan.) sparingly perforate, with 4-6(7) primary lateral veins per side (or primary lateral veins obscure), the margins entire. Peduncle 0.9-3.5 cm. Spathe color unknown. Spadix ca. 4.5-9 × 1.5-2.4 cm. Infr. color unknown. Wet forests, 0-800 m; Atl. slope. Cords. Tilarán, Central (to R.N.F.S. Barra del Colorado), and Talamanca, Pac. slope S from R.B. Carara. Fl. Feb., Apr., Jun.-Aug., Nov., -Dec. CR (and ostensibly extreme SE Nic.) to Pac. Col. (Grayum & Hammel 5523; CR, MO) Monstera pittieri belongs to a group of spp. characterized by shingle-forming juvenile leaves, a high-climbing, pendent growth habit, deciduous petiole sheaths, marginally entire and usually imperforate adult leaf-blades, and short (relative to the spadix) peduncles. Within this group, it most resembles the potentially sympatric M. luteynii (which see for additional remarks). Other CR spp. with which M. pittieri might conceivably be confused are M. obliqua and M. spruceana (see under those entries). Pac. slope populations of M. pittieri diverge somewhat in having strongly falcate and more inequilateral leaf-blades, as well as smaller infls. Monstera pittieri seems always to have imperforate leaf-blades in CR, though plants in some Panamanian populations have perforate blades. Monstera punctulata (Schott) Schott ex Engl., in A. DC. & C. DC., Monogr. phan. 2: 259. 1879. Anadendrum punctulatum Schott, Prodr. syst. Aroid. 393. 1860. Coarse, appressed-climbing trunk epiphytes, fertile ca. 5-12 m above ground (occasionally on rocks when juvenile). Juvenile leaves shingle-forming. Petioles of adult leaves ca. 30-65 cm, ± roughened and speckled toward base, sheathed to near geniculum, the sheath deciduous. Leaf-blades 47-112 × 28-64 cm, ovate to broadly elliptical or oblong, cordate at base, subcoriaceous, perforate, with ca. 11-18 primary lateral veins per side, the margins pinnatifid. Peduncle 6.5-18 cm. Spathe cream-yellow within, yellowish green externally. Spadix ca. 10-15 × 2.4-2.7 cm. Infrs. green to brownish. Wet to seasonally dry forests, (600-)900-1800 m; Atl. slope. Cord. Talamanca (basin of Río Reventazón and Río Chirripó), Pac. slope Valle Central, Cord. Talamanca. Fl. Feb.-Apr., Jul., Aug. Mex. to Pan. (Grayum & Hammel 5691; CR, MO) Monstera punctulata is quite similar to M. dubia (see key, couplet 5), the only CR sp. with which it is likely to be confused. These two spp. do not occur sympatrically anywhere in CR. Though locally abundant in the Coto Brus region, M. punctulata is generally an uncommon sp. in CR. Plants of M. punctulata are of ornamental value due to their bold, bright green, perforate and pinnatifid leaf-blades; the sp. is occasionally seen in cult., as in the inner courtyard of the Museo Nacional. Monstera spruceana (Schott) Engl., in Mart., Fl. bras. 3(2): 115. 1878. Tornelia spruceana Schott, Oesterr. Bot. Z. 9: 40. 1859. Appressed-climbing trunk epiphytes, fertile ca. 7-10 m above ground. Juvenile leaves shingle-forming, plain green. Petioles of adult leaves ca. 21-52 cm, ± striate (dried) and speckled, sheathed to geniculum, the sheath deciduous. Adult leaf-blades 22-59 × 7-27 cm, lanceolate or narrowly elliptic to ovate, cuneate to rounded or subtruncate at base, subcoriaceous to coriaceous, imperforate, with ca. 8-16 primary lateral veins per side, the margins entire or (rarely, in CR) broadly few-pinnatifid. Peduncle 6-13 cm. Spathe "pale yellowish" (Skutch 5320, US). Spadix 11.5-20 × 2.7-3.4 cm. Infrs. becoming yellowish. Wet forests, 0-1200 m; Atl. slope. Cords. Guanacaste, Central (to R.N.F.S. Barra del Colorado), and Talamanca, Pac. slope S from Dominical. Fl. Jan., Feb., Apr., Jul., Sep.-Dec. CR (and ostensibly extreme SE Nic.) to Bol., Guianas, Braz. (Grayum & Sleeper 4352; CR, MO) This sp. is unusually distinctive by virtue of its high-growing, appressed-climbing habit, deciduous petiole sheaths, generally ± narrow, imperforate, usually marginally entire, gray-drying leaf-blades, and short (relative to the spadix) peduncles. It is perhaps most similar to M. pittieri, but the latter sp. comprises more loosely scandent plants that are smaller in all of their parts. Throughout the larger part of its geographic range, Monstera spruceana generally has coarsely pinnatifid leaf-blades. In CR, however, its leaf-blades almost invariably have entire margins. Material from N Cent. Amer. that appears virtually inseparable from M. spruceana (except that it may sometimes have perforate leaf-blades) is customarily identified as M. acuminata K. Koch. Should these entities prove conspecific, M. acuminata has priority. Monstera standleyana G. S. Bunting, Baileya 14: 133. 1966. M. lechleriana sensu Madison (1977, pro parte), non Schott. Stout, appressed-climbing trunk epiphytes, fertile ca. 2-8 m above ground. Juvenile leaves not shingle-forming. Petioles of adult leaves (17-)39-80 cm, smooth, sheathed to near base of blade, the sheath persistent. Leaf-blades ca. (29-)46-82 × (11-)19-42 cm, lance-ovate to lanceolate, cuneate to rounded or truncate at base, subcoriaceous to coriaceous, imperforate or (rarely, in CR) perforate, with 12-25 primary lateral veins per side, the margins entire. Peduncle (7-)17-40 cm. Spathe cream-whitish white within. Spadix ca. 9-17 × 2.8-4.2 cm. Infr. color unknown. Wet forests, 0-1150 m; entire Atl. slope and near Continental Divide. Fl. Apr.-Jun., Aug., Sep. Extreme SE Nic. to cent. Pan. (Grayum & Hodel 9728; CR, MO) Monstera standleyana is very distinctive in its robust habit, brief internodes, strikingly distichous leaves, prominent, persistent petiole sheaths, imperforate (usually) and marginally entire, thickish, adaxially glossy, dark-drying leaf-blades with relatively numerous primary lateral veins, and very thick spadices. Very few CR populations have perforate leaf-blades [e.g., Hammel et al. 15299 (MO), from RB Brenes]. Widely scattered montane (mostly > 1200 m) collections with deciduous petiole sheaths and ± coriaceous, occasionally pinnatifid, reddish-brown-drying leaf-blades have sometimes been identified as this sp. Some similar Panamanian collections are annotated by Madison as intermediates, or putative hybrids, between this sp. ("M. lechleriana") and M. adansonii. It is also possible that this material represents one or more distinct spp. Monstera tenuis K. Koch, in A. Braun et al., Append. gen. sp. Hort. berol. 1855 4. 1855-1856. M. gigantea Engl., non (Roxb.) Schott. Coarse, appressed-climbing trunk epiphytes, fertile ca. 5-10+ m above ground. Juvenile leaves shingle-forming, plain green. Petioles of adult leaf-blades ca. (16-)21-67 cm, ± smooth, sheathed to near base of blade, the sheath ultimately deciduous. Leaf-blades ca. (26-)50-115+ × 28-65+ cm, narrowly ovate to lance-oblong, broadly cuneate to rounded or truncate at base, subcoriaceous, imperforate, the margins deeply and ± regularly pinnatifid (with ca. 10-30 lobes and 1 primary lateral vein per lobe). Peduncle 4-13(-15) cm. Spathe cream-white within. Spadix ca. 15-32 × 3-5 cm. Infrs. cream-yellowish. Wet forests, 0-1300(-1750+) m; throughout. Fl. Jan., Mar., May-Jul., Sep., Oct., Dec. SE Nic. to W Pan. (Gómez et al. 20317; CR, MO) Monstera tenuis is immediately recognized by its high-growing, appressed-climbing habit, long, ± narrow, multi-pinnatifid leaf-blades, and immense infls. Because of their leaf-blades, deeply and regularly divided into narrow lobes, these plants have a distinctly fernlike aspect. In CR, this is the most abundant and widespread Monstera sp. with shingle-forming juvenile foliage. Monstera tuberculata Lundell, Lloydia 2: 78. 1939. Epiphytic vines, climbing into the canopy, the stems pendent. Juvenile leaves shingle-forming, silvery-variegated. Petioles of adult leaves 1.5-6 cm, ± smooth, sheathed to geniculum, the sheath distally prolonged in a free ligule ca. 0.8-5.5+ cm long, deciduous. Leaf-blades ca. 5.5-15 × 3.5-11 cm, ovate, cordulate to cordate at base, coriaceous, imperforate, with ca. 4-7 usually obscure primary lateral veins per side, the margins entire. Peduncle ca. 2-5 cm. Spathe whitish within. Spadix ca. 3.5-5.5 × 1.4-1.9 cm, with curved, elongate, conical styles. Infrs. green. Wet forests, 0-800(-1100) m; entire Atl. slope. Fl. Jan., Feb., Apr., Jun., Jul. Mex. (Oax., Ver.) to extreme NW Pan. (Q. Jiménez et al. 962, INB, MO) Monstera tuberculata bears a strong superficial resemblance to other Monstera spp. comprising small-leaved, canopy vines with pendent flowering stems, especially M. luteynii and M. pittieri. It is, however, easily distinguished from these by both vegetative and reproductive characters (see key, couplet 11). The silvery variegation of the shingle-leaves may be unique to this sp. (juvenile foliage of some other spp., including M. luteynii, is unknown). Costa Rican material of M. tuberculata corresponds to var. brevinoda (Standl. & L. O. Williams) Madison (Contr. Gray Herb. 207: 92. 1977; Philodendron brevinodum Standl. & L. O. Williams, Ceiba 1: 231. 1951), of SE Nic. to Pan. Montrichardia Engler, A. 1911. Lasioideae. In A. Engler (ed.), Das Pflanzenreich IV.23 (Heft 48): 1-130. Engelmann, Berlin. 2 spp., Bel. to trop. South Amer., WI; 1 sp. in CR. Montrichardia arborescens (L.) Schott, Arac. Betreff. 1: 4. 1854. Arum arborescens L., Sp. pl. 967. 1753. Terrestrial, paludal; stems erect, 2-5.5(-9) m tall, simple or sparingly branched, aculeate; plants without milky sap. Leaves spiraled. Petioles ca. 18-46 cm, not peltately attached, lacking a geniculum. Leaf-blades simple, ca. 22-41 × 15-31 cm, deeply sagittate or subhastate, with ca. 4-6 primary lateral veins per side, the margins entire. Infls. 1 (rarely 2) per axil. Spathe erect, weakly differentiated into proximal tube and distal lamina; tube rose-pink within, greenish white externally; lamina cream-white within. Peduncle ca. 7-9 cm. Spadix ca. 10-13 cm, with separate male and female regions, without sterile zones or appendages. Fls. unisexual, naked; male fls. with 3-6 distinct, prismatic stamens; female fls. without obvious style; stigma sessile in a central umbo; ovary unilocular; ovules 1 or 2, borne basally. Frs. ca. 2-3.5 × 1.5-2.5 cm, obturbinate to obovoid, ± spongy, becoming pale yellowish, 1-seeded. Seeds blackish. Lagoons, estuaries, river margins, canals, and swamp forests, 0-50 m; Atl. coastal plain. Fl. Jan., Sep., Nov. Bel. to Perú, Guianas, Braz., WI. (J. F. Morales et al. 1644; INB, MO) Montrichardia arborescens is easily recognized among CR Araceae by its coastal, subaquatic habitat, elongate, spindly, aculeate stems, and simple, sagittate leaf-blades with prominent posterior lobes. The infls. are similar to those of Philodendron spp., but the very large, spongy frs. are distinctive. In CR, M. arborescens is perhaps most likely to be confused with Urospatha grandis, of similar habitats, but lacking an aerial stem and with very different infls. of bisexual, perigoniate fls. Compare also Homalomena wendlandii, which is always acaulescent, and Xanthosoma undipes, which has relatively stouter stems and copious milky sap in all of its parts. Though quintessentially a coastal sp. in Central Amer., M. arborescens may occur well inland in suitable habitats, at least as far as the vicinity of Puerto Viejo de Sarapiquí in CR. TOP