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NSF-PEET project in Systematic
Bryology
Missouri Botanical Garden
ABSTRACTS OF
NSF-PEET PRODUCTS
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ABSTRACTS OF PAPERS PRESENTED BY NSF-PEET STUDENTS |
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ABLS 1998: San Juan, Puerto Rico |
CASADO,
CHRISTINA M., Missouri Botanical Garden, PO Box 299, St. Louis, Missouri
63166-0299, Monograph of the genus Streptopogon Wils. (Pottiaceae),
including cladistic analysis and the examination of diagnostic anatomical
features. Streptopogon (Pottiaceae) is a
tropical moss genus with 14 currently accepted taxa and 20 synonyms. Some species in the genus share
morphological similarities with the genus Calymperes, such as
propagula borne at the leaf apices.
Ecologically, Streptopogon is somewhat atypical for the
Pottiaceae which inhabit arid environments, by occurring on trees (trunks and
branches) and rocks in humid montane forests. Given these morphological and
ecological peculiarities, as well as the need for taxonomic revision, I have
begun the alpha taxonomic study on the genus and will follow up with a
cladistic analysis for the monograph. I also intend to examine morphological features for each
species, focusing on the reproductive function of the propagula. Streptopogon will also be
scrutinized from a biogeographical perspective. It occurs throughout Latin America, Central and Southern Africa,
Madagascar, Hawaii, and possibly the South Pacific. Its ecological niche
(unusual for the Potticaeae) and its tropical affinities can be used to map
the distribution of the genus and to identify where one might expect it to
occur outside its current range. Furthermore, mapping geographical data onto
a phylogeny may provide insight as to the historical biogeography of Streptopogon. |
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ABLS 1996: Montreal, Canada |
A revision of Afro-American
genus Pilotrichella s.s. (Meteoriaceae).Zacharia L.K. Magombo,
Michelle J. Price, and Steven P. Churchill The previous concept
of the Meteoriaceous genus Pilotrichella is now known to contain two
elements, which may not be closely related, Orthostichella and Pilotrichella
s.s. The first stage of a revision of these elements focuses on Pilotrichella
s.s. The genus is characterized by its pendent habit, or occasionally
forming loose mats, generally robust size, branch leaves arranged in straight
rows, well developed, excavate alar cells, and basally striate exostome
teeth. Orthostichella is likewise pendent, however, the plants are
slender in size, with branch leaves arranged in helical or striate rows,
weakly developed alar cells, and papillose exostome teeth. Species
representing the Pilotrichella s.s. in the Neotropics include P.
flexilis, the common and widespread species associated with montane
forests (also disjunct to Madagascar), and P. quitensis, restricted to
high elevational montane Ecuador south to Bolivia, P. cuspidans, known
only from Hispaniola and Cuba. The status of at least two species from SE
Brazil are still under investigation. Of the remaining species, P.
mauiensis, from the Pacific Hawaiian Islands appears only weakly distinct
from P. flexilis. |
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ABLS 1998: San Juan, Puerto Rico |
Taxonomic relationships of
New World Diphyscium (Musci: Buxbaumiaceae). Zacharia L.K. Magombo Twenty three
species of the genus Diphyscium are currently known to be distributed
in the world. They are grouped into three groups according to leaf
characters: (i) species with smooth leaf cells, (ii) species with
pleuripappillose leaf cells, and (iii) species with unipapillose to
mammillose leaf cells. Previously
twenty species were known to be geographically restricted with 5
species in the New World, 2 in Oceania, 1 in Africa and 12 in Asia. Recently
Diphysciun poscii previously known only from Africa was found in
Honduras. There is a total of 7 species in the New World. As is the case with
Diphyscium else where, the New World species are not well separated
and may not be taxonomically different. This paper discusses taxonomic relationships
among New World species. |
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ABLS 2000, Southern Illinois
University, Carbondale, Ilinois |
Synopsis on the taxonomy
and biogeography of the moss genus Floribundaria Müll. Hal. ex
Fleisch. (Meteoriaceae). Zacharia L.K. Magombo The moss genus Floribundaria
Müll. Hal. ex Fleisch. in the family Meteoriaceae is distinguished by a
combination of characters including (1) seriately arranged papillae on the
cell lumen, (2) cucullate calyptrae, (3) double peristome with striate
exostomes, and (4) U-shaped leaf insertion. There are currently 17 names in
use. However, preliminary studied indicate that some of the species may not
be distinct, for example, F. usneioides (Broth.) Broth. in the New
World may be synonymous with F. vaginans (Welwitsch & Duby) Broth.
in the Old World. Circumscription of species is not clear due to significant
variation in morphological characters, and lack of comprehensive taxonomic
treatment. The distribution pattern exhibited by species in the genus raises
interesting questions related to biogeography. This paper gives an overview
of the variation in morphological characters and hence implications on the
circumscription of taxa, and insights into the biogeography of the group. |
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ABLS 1996: Montreal, Canada |
PRICE,
MICHELLE J. Missouri Botanical Garden, PO Box 299, St. Louis, MO 63166-0299.
- Life-form of bryophytes from upper-montane woodlands of the Ecuadorian
Andes. The life-form of a
bryophyte is an ecological description of its characteristic shapes and
structure. The various life-forms apparent can be viewed as resultant from
interactions of the plants physiological functioning, developmental
constraints and environmental relationships, an overall acclimative response.
Thirty three species of epiphytic and terricolous bryophytes growing in
upper-montane woodlands of El Cajas National Recreation Park, Ecuador were
investigated in terms of their life-forms. One of the objectives of the study
was to determine the ecological significance of life-form in influencing
bryophyte distributional patterns. The study was facilitated by a review of the
schematic and descriptive usage of bryophyte life-form and the construction
of a life-form scheme applicable both locally and in other montane regions.
Cushion, pendant and mat forms were the most frequently recorded forms and of
the species investigated differing degrees in plasticity of form were found.
A common species Dicranum frigidum was observed in several forms
depending on whether it grew in association with other species. Microhabitat
factors of temperature, humidity and light availability, for a selected
number of the epiphytic bryophyte species were measured, and preliminary
analyses indicated that life-form distribution varied over the trees
structure in accordance with a combination of microhabitat factors and these
were ultimately influenced by the macroenvironmetal factors of determined by
woodland structure and site conditions. |
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ABLS 1996: Montrea, Canada |
PRICE,
MICHELLE J.* AND CHURCHILL, STEVE P. Missouri Botanical Garden, PO. Box 299,
St.Louis, MO 63166-0299. - Holomitrium (Dicraneaceae) of the Northern
Andes. Holomitrium Bridel. forms a generic
complex with two closely related families in Dicraneaceae. This complex is
marked by five morphological features: a strong single costa, well developed
alar cells, long and sheathing perichaetial leaves, erect capsules and
undivided peristome teeth. The members are acrocarpous medium to large sized
plants which are commonly epiphytic in habit. Generally there are few unique
features separating the three genera. Holomitrium is best recognized
by the contrast in the shape and size of the upper and lower leaf cells;
upper leaf cells are short and straight with the lower leaf cells elongate
and porose. Holomitrium terebellatum C. Müller in Ren & Card. ,
H. flexuosum Mitten and H. sinuosum B.H. Allen are exceptions to
this possessing more weakly differentiated basal and upper leaf cells. The
genus Holomitrium is represented by twenty known species in the
Neotropics and of these twelve species form a subset in the Northern Andes.
The greatest diversity of species is to be found in montane regions exceeding
2000m elevation. Recently field work in the montane forests of Colombia and
Ecuador has resulted in the collection of three new species, to be described.
Previously all Andean species possesed a toothed margin and one of the new
species described from Ecuador has an entire margin. The discovery of these
three new species represents an interesting development in the understood
taxonomic status of Holomitrium in the Andean region and of the
diversity of tropical montane mosses as a whole. |
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ABLS 1998: San Juan, Puerto Rico |
PRICE
MICHELLE. J. Missouri Botanical Garden, P.O. Box 299, St. Louis, MO
63166-0299. A revision of the genus Rhynchostegiopsis Müll. Hal.
(Hookeriaceae: Musci). Rhynchostegiopsis is a small Neotropical
genus reported from Mexico, Central America, and the Caribbean to South
America. It has been placed in the Leucomiaceae (Allen, 1987; Buck, 1988) or
Hookeriaceae (Whittemore & Allen, 1989). Rhynchostegiopsis is
placed in the Hookeriales on account of both gametophytic and sporophytic
characters. The genus, described in 1897, comprises eight taxa. It is
characterised by serrate leaf margins, absoulutely ecostate leaves with thin
walled long lax leaf cells, no central strand, no pseudoparaphyllia and well
developed endostomial cilia. Rhynchostegiopsis auricolor and Rhynchostegiopsis
cupressina are considered synonyms of R. flexuosa (Wijk et al.,
1962) and R. lutescens has been placed in synonomy with R. tunguraguana (Crum, 1994). Rhynchostegiopsis
species are found on logs, soil and trees in hmid forests over a range of
elevations. |
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ABLS 2000: Portland, Oregon |
PRICE,
MICHELLE J., Missouri Botanical Garden, P.O. Box 299, St. Louis, MO
63166-0299. A preliminary cladistic analysis of the Dicranoideae
(Dicranaceae, Musci) based on morphology. The Dicranaceae,
a large and variable moss family, contains around 1000 species and 55 genera
that are divided into several weakly demarcated subfamilies. The large
subfamily Dicranoideae is generally characterized by: a narrow costa; well
developed alar cells; differentiated perichaetial leaves; a short capsule
neck; phaneroporic stomata; and variously bifid or undivided papillose
peristome teeth. A preliminary cladistic analysis of 51 taxa using 35 morphological
characters indicates that there are two main groups in the subfamily. One
centered around Holomitrium (including Eucamptodontopsis and Schliephackea)
and one around Dicranum-Leucoloma.
This analysis has highlighted some of the problems associated with
character evaluation in a group where characters are variable both between
and within genera. |
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PEET Abstracts, Meeting in Woods Hole
Oceanographic Institute, 1998 |
CHURCHILL,
Steven, P (PI)., MAGOMBO, Zacharia. L.K, CASADO, Christina. M, and PRICE,
Michelle. J. Missouri Botanical Garden, P.O. BOX 299, St. Louis, MO
63166-0299, USA. Systematic revision of Pilotrichella (Musci:
Meteoriaceae). Pilotrichella (ca. 60 taxa) is placed in the Meteoriaceae (22
genera, 300 taxa), a family of tropical epiphytic mosses. The Meteoriaceae
are divided into two subfamilies, the Meteorioideae (14 genera) and
Pilotrichelloideae (8 genera). Pilotrichella and Barbella, are
the only genera of the Pilotrichelloideae which have not been subjected to
recent revisionary work. Pilotrichella is to be critically revised
using traditional morphological methodology. Preliminary studies suggest two
elements within the genus, Pilotrichella s.s. and Orthostichella. Morphological
characters will be analysed and coded during the study for use in both the
revisionary work and phylogenetic analyses. The objectives of the work are to produce a cohesive monograph
of Pilotrichella using the plant taxonomic data base TROPICOS for data
manipulation and management. Monographic results from Pilotrichella
and the Pilotrichelloideae will be further employed in a cladistic analysis
of the generic relationships within the subfamily and to fully circumscribe
it. Concurrent to revisionary work, molecular data will be gathered on the
Pilotrichelloideae allowing a molecular based phylogeny to be generated and
tested against the morphologically based phylogeny. The main aim of the
project is to provide training in systematic techniques and database
management, the integration of traditional and modern systematic techniques
and the dissemination of results through a variety of media. MAGOMBO, Zacharia L.K.
Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166-0299, USA. Taxonomic and
phylogenetic study of the Floribundaria/Trachycladiella complex
(Meteorioideae: Meteoriaceae). The tropical moss genera Floribundaria Mull.Hal ex
Fleisch. and Trachycladiella (M. Fleisch.) Menzel & Schultze-Motel
(segregate of Floribundaria) of the subfamily Meteorioideae
(Meteoriaceae) apparently form a group distinguished by a combination of
characters including flattened branches, complanate-foliation, leaves with
somewhat clasping bases, seriately papillose leaf cells, and axillary hairs
with one or two brown basal cells and one hyaline apical cell. The genera are
distinguished by the position of the papillae over the lumen, in Floribundaria,
and papillae over the walls and lumen, in Trachycladiella. As
currently understood the taxa involved have an interesting geographic
distribution. The genus Trachycladiella is limited to tropical Asia
while Floribundaria has some taxa limited to tropical America, Africa,
Asia and yet others are found throughout the Old World tropics. While these
genera are assumed to be monophyletic they are not properly circumscribed due
to the great variation among the taxa. A revision will be on a global scale.
Both morphological and molecular data will be used to resolve phylogenetic
relationships among the taxa. This research project fits well within the
current initiative at Missouri Botanical Garden where monographic work of the
genus Pilotrichella (Meteoriaceae) is underway. These revisionary
studies will provide additional data towards a circumscription of the
Meteoriaceae. CASADO, CHRISTINA
M.,Missouri Botanical Garden, PO Box 299, St. Louis, Missouri 63166-0299,
Monograph of the genus Streptopogon Wils. (Pottiaceae), including
cladistic analysis and the examination of diagnostic anatomical features. Streptopogon (Pottiaceae) is a
tropical moss genus with 14 currently accepted taxa and 20 synonyms. Some species in the genus share
morphological similarities with the genus Calymperes, such as
propagula borne at the leaf apices.
Ecologically, Streptopogon is somewhat atypical for the Pottiaceae
which inhabit arid environments, by occurring on trees (trunks and
branches) and rocks in humid montane forests. Given these morphological and
ecological peculiarities, as well as the need for taxonomic revision, I have
begun the alpha taxonomic study on the genus and will follow up with a
cladistic analysis for the monograph.
I also intend to examine morphological features for each species,
focusing on the reproductive function of the propagula. Streptopogon will also be
scrutinized from a biogeographical perspective. It occurs throughout Latin America, Central and Southern
Africa, Madagascar, Hawaii, and possibly the South Pacific. Its ecological
niche (unusual for the Potticaeae) and its tropical affinities can be used to
map the distribution of the genus and to identify where one might expect it
to occur outside its current range. Furthermore, mapping geographical data
onto a phylogeny may provide insight as to the historical biogeography of Streptopogon. PRICE, Michelle, J.
Missouri Botanical Garden, P.O. BOX 299, St. Louis, MO 63166-0299, USA.
Systematic revision of Holomitrium Bridel (Musci: Dicranaceae). Holomitrium (ca. 50 taxa) is a tropical-subtropical epiphytic
genus, with the majority of species found in montane or sub-montane areas. Holomitrium
has been placed in the Dicranaceae, subfamily Dicranoideae. Plants are
characterized by a well developed alar region; a marked contrast between
upper and lower leaf cells with the upper leaf cells being short and straight
and lower leaf cells elongate and porose; serrate to crenulate or entire leaf
margins sometimes bistratose; leaves crispate to infrequently spirally
contorted when dry; strong single costa percurrent to slightly excurrent;
costa smooth or with a few teeth at the back; long sheathing perichaetial
leaves; and undivided to more or less fenestrate peristome teeth which are
papillose on outer surface. The genus was formerly divided into two
sections, Holomitrium and Macrodictyon although the later
section was raised to the generic level because of its appressed,
non-crispate leave, elongate cells throughout, smaller perichaetial leaves,
and reduced ventral sterids with a lesser number of guide cells in the costa.
Sporophyte characters were not used in this segregation. Holomitrium
forms a generic complex with two neotropical genera Eucamptodontopsis
and Schliephackea marked by well developed alar cells, a strong single
costa, long sheathing perichaetial leaves, erect capsules, and undivided
peristome teeth. Few unique characters serve to separate these genera. The aim of
the project is a systematic revision of Holomitrium, and the three
closely associated genera, using traditional morphological methodology.
During this revisionary process characters of potential phylogenetic
significance will be identified and evaluated before being used to further
investigate Holomitrium, Macrodictyum and the other related genera
cladistically. Molecular data will then be used to corroborate the results
and to re-evaluate the morphological characters. Incorporated into the
phylogenetic analysis and monograph will be aspects of the ecology, sexuality
including the dwarf male syndrome, phenology, and biogeography. The data will
be managed using the plant taxonomic database TROPICOS and results are to be
disseminated through the World Wide Web, and printed media |
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Webpages prepared by Michelle Price, 2001. Updated March 2001. mailto:mprice@lehmann.mobot.org
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