|
Flora of the Venezuelan Guayana
<< Back
BIGNONIACEAE
11. DIGOMPHIA Benth., Hooker's J. Bot. Kew Gard. Misc. 5: 364. 1846.
Trees or shrubs. Leaves simple or odd-pinnately compound. Inflorescence a few-flowered terminal panicle, frequently reduced to 1 or 2 flowers. Calyx large, membranous, spathaceous or split into 3-5 lanceolate or ovate lobes; corolla lavender or bluish purple, tubular-campanulate, mostly glabrous outside. Anthers glabrous, bithecate, the staminode elongate, exceeding the stamens, bifurcate or 4-6-parted at apex, glandular pubescent in upper 2/3. Ovary compressed-elliptic, glabrous; disk pulvinate. Capsule elliptic, flattened perpendicular to the septum, dehiscing perpendicular to the septum and parallel to the plane of compression. Seeds thin, winged.
Endemic to the Guayana Shield in southeastern Colombia, southern Venezuela, Guyana, and northern Brazil; 3 species, all in the flora area.
Key to the Species of Digomphia
1. Leaves pinnately compound ..... D. densicoma
1. Leaves simple ..... 2
2(1). Staminode 4-6-parted at apex; leaves narrowly elliptic (> 2.5 times as long as wide); below 200 m elevation; fruit apex truncate ..... D. ceratophora
2. Staminode bifurcate at apex; leaves elliptic (almost always less than 2.5 times as long as wide); above 500 m elevation; fruit apex usually ± acute ..... D. laurifolia
Digomphia ceratophora A.H. Gentry, Mem. New York Bot. Gard. 29: 270. 1978.
Small shrub. White-sand savannas, 100-200 m; Amazonas (middle Río Orinoco). Adjacent Colombia (Vaupés).
Digomphia densicoma (Mart. ex A. DC.) Pilger, Repert. Spec. Nov. Regni Veg. 8: 151. 1910. -Jacaranda densicoma Mart. ex A. DC., Prodr. 9: 232. 1845.
Shrub or large tree. Shrublands and low forests on tepui slopes and summits, 600-2100 m; southern Bolívar, Amazonas (widespread). Adjacent Colombia, Guyana (Pakaraima Mountains), Brazil (Amazonas: Serra Aracá). Fig. 372.
Digomphia laurifolia Benth., Hooker's J. Bot. Kew Gard. Misc. 5: 364. 1846.
Shrub or small tree. Shrublands and low forests on tepui slopes and summits, 700-2500 m; Bolívar (Gran Sabana), Amazonas (Cerro Parú). Adjacent Guyana, Brazil (Amazonas: Serra Aracá). Fig. 371.
Scientific Comments:
Paul Berry (peberry@facstaff.wisc.edu) or Kay Yatskievych (kay.yatskievych@mobot.org).
|