Gesneriaceae in the 21st Century

2005·0.47 MB·

by  Skog, Laurence E

Selbyana 25(2): 179-181. 2005.
GESNERIACEAE IN THE 21sT CENTURY
LAURENCE E. SKOG
Department of Botany, National Museum of Natural History, Smithsonian Institution; Marie
Selby Botanical Gardens. Mailing address: MRC-166, P.O. Box 37012, Washington, DC
20013-7012 USA. Email: [email protected]
INTRODUCTION cies-rich treatment of the Gesneriaceae for the
Flora of China (Wang et al. 1998), which in
Since the founding of the Marie Selby Botan cludes ca. 116 of the species in the family. Un
ical Gardens (MSBG) more than 30 years ago, fortunately, fewer specialists are encouraged to
the study and display of Gesneriaceae have been undertake large projects, however valuable they
an integral part of the institution. On the original are for conservation (Skog 2005) and ecological
Selby Gardens seal, gesneriads, as one of the monitoring (Kvist et al. 2004).
three plant families in the design, are represent
ed by Columnea. Although there have been pe
GESNERIAD FAMILY MEMBERS
riods of less activity on Gesneriaceae at Selby
Gardens and in the world of research in general, For the ca. 3200 species in ca. 159 genera in
recent research before and since the turn of the Gesneriaceae listed in the World Checklist of
21st century has made the Gesneriaceae an ac Gesneriaceae (Skog & Boggan 2005a), the ten
tive area of study. The three articles on Gesner largest genera are the following:
iaceae presented in this issue of Selbyana are
Cyrtandra ±600 species
evidence of the continuing commitment to re
Columnea ::1::200 species
search on Gesneriaceae at Selby Gardens. These
Aeschynanthus ± 180 species
articles are good examples of current research in
Chirita ± 180 species
the family.
Henckelia ± 155 species
Gesneriaceae research is being undertaken in
Streptocarpus ± 155 species
a range of studies in many parts of the world. A
Besleria ± 150 species
symposium at Edinburgh, Scotland, in 2002 and
Didymocarpus ± 100 species
the symposium at the 2005 XVII International
Agalmyla ±95 species
Botanical Congress in Vienna, Austria, revealed
Paraboea ±90 species
the various activities and the many individuals
who are now active in research in Gesneriaceae All of these genera have received or are re
in Europe, Asia, Australia, Africa, as well as ceiving attention to some degree, some through
North and South America. MSBG and The Ges out their range, and some as topics for single
neriad Society (formerly the American Gloxinia country floras. Much remains to be done. Ac
& Gesneriad Society) have established an asso cording to the Checklist, there are ±75 genera
ciation to underwrite and encourage gesneriad (nearly half of the genera in the gesneriad fam
research and publication at Selby Gardens. ily) that have only one or two species. All of
Funding, not only from MSBG, but also from these small genera need to be examined more
the research endowment fund of The Gesneriad closely, using molecular techniques coupled
Society, the U.S. National Science Foundation, with morphological examination, to identify
and many other sources has moved research for their affinities. Anyone who visits herbaria to
ward on many fronts. examine Gesneriaceae can find dozens to thou
Classical floristic and revisionary studies, sands of unidentified specimens, a sign that there
along with discovery and description of new are yet many genera and species to be discov
genera and species, have continued unabated, ered. In the neotropics alone, some medium
exemplified by the article included here on Ne sized genera with numerous named species and
matanthus by Chautems et al. In addition, other unidentified specimens, such as Drymonia, Par
noteworthy revisions in the past 10 years include adrymonia, Nautilocalyx, Diastema, Monopyle,
among many, the generic revisions of, e.g., etc., all beg for attention. Some areas of study
Agalmyla (Hilliard & Burtt 2002) and the Di currently are less emphasized, i.e., anatomy, cy
dymocarpus complex (Weber & Burtt 1998) in tology, carpology, pollen and seeds, and embry
the Old World and Pearcea (Kvist & Skog ology; yet these and other areas are revealing
1996), Gasteranthus (Skog & Kvist 2000), and useful characters and information. For example,
Solenophora (Weigend & Forther 2002) in the cytological research is being undertaken in Ed
New World. Floristic treatments include the spe- inburgh and Vienna (Moller & Kiehn 2004), flo-
179
180 SELBYANA Volume 25(2) 2005
ral arrangement (Citerne et al. 2000), evolution alignment of the tribes, as can be seen in the
(Denduangboripant et al. 2001); and pollination revival of tribe Sinningieae (Perret et al. 2003),
ecology currently is under study by several stu and the description of the new tribe, Sphaeror
dents. The large number of publications that rhizeae. This latter tribe, described in the Roal
have appeared during the past decade prevents son et al. article, necessitates the ongoing and
review here of all the areas of research in Ges forthcoming revision of the classification of the
neriaceae, but a search in the online Bibliogra Gesneriaceae by Burtt and Wiehler (1995).
phy of Gesneriaceae (Skog & Boggan 200Sb) These are just a few examples that can be drawn
shows the vast number of papers and directions from recent literature.
of research.
As with many other families of plants, the ad
CONCLUSION
vent of molecular studies, particularly system
atics, has ushered in new techniques and a closer Research in Gesneriaceae is underpinned by
examination of taxa. The gesneriad family still fieldwork, including field observations and spec
comprises two or three subfamilies, Cyrtandro imen gathering for herbarium research. The re
ideae, Gesnerioideae, and Coronantheroideae. cent acquisition by Selby Gardens of the valu
Fortunately the family is not split up like the able herbarium of the Gesneriad Research Foun
Scrophulariaceae (Olmstead et al. 2001) or other dation, amassed by the late Hans Wiehler, will
related families in the Lamiales. Several recent provide valuable specimens for floristic and re
papers (e.g., Olmstead & Reeves 1995, Oxelman visionary research by students. Fieldwork still
et al. 1999, Spangler & Olmstead 1999, Wag forms the basis of all types of research in Ges
staff & Olmstead 1997) suggest that the Ges neriaceae, including molecular and morpholog
neriaceae is one of the oldest families in the ical investigations. More recent examples of
Lamiales and may provide insights into the or fieldwork include the work of John R. Clark on
igin and early diversification of the Lamiales. Cyrtandra in the South Pacific, Silvana Martens
The article in this issue by Roalson et al. in on the pollination ecology in the Gesnerieae on
cludes name changes resulting from a combi the Caribbean islands, the search for Gesneri
nation of molecular and morphological research, aceae in the unexplored mountains in Indonesia
which found that molecular characters could be by the New England Tropical Conservatory and
correlated with morphological differences. From their colleagues at the Bogor Botanical Garden,
this, it became clear that generic concepts and and fieldwork by two of the authors of the arti
placement of genera in certain tribes have been cles included here: John L. Clark on Alloplectus
incorrect. Placement and relationships become in the neotropics and Alain Chautems on Ne
obvious in closer examination of the morpho matanthus in Brazil.
logical characters, when preliminary clues are Another fortunate result of fieldwork is the
revealed by molecular studies. The article by discovery of new species in the wild, species
J.L. Clark is the result of molecular and mor useful in horticulture for ornamental display and
phological studies of the genus Alloplectus. Dur hybridization.
ing fieldwork, Clark discovered that upside During the last two decades, the use of com
down flowers serve to distinguish the resurrect puters for data basing, word processing, and data
ed genus Glossoloma, within the large Alloplec analysis has increased productivity in all areas
tus s.l. of research. Available online are the following
In recent years, molecular systematics has resources: the World Checklist of Gesneriaceae
been used in many parts of the family, in many (Skog & Boggan 2005a) and the Bibliography
genera, to give us a clearer picture of the generic of Gesneriaceae (Skog & Boggan 2005b), both
and tribal limits. Startling examples of possible mentioned above; the Genera of Gesneriaceae
resorting and combining of genera can be seen (Weber & Skog 2003); Selby Gardens research
in the close relationship and nesting of Saint in Gesneriaceae (www.selby.org); and the web
paulia within Streptocarpus (Moller & Cronk site of The Gesneriad Society (www.aggs.org).
1997), Capanea within Kohleria (Roalson et al. All of these websites list additional URLs (Uni
2005), Anodiscus and Koellikeria within Glox form Resource Locators) that provide links to
inia s.s. (Roalson et al. this issue), and the close other websites on research in Gesneriaceae.
relationship of the genera Achimenes, a low ter
restrial herb, with Solenophora, a genus of often
LITERATURE CITED
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Poorly defined and heterogeneous genera are be
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morphological studies. As a result, there is a re- versity of cycloidea-like genes in Gesneriaceae in
SKOG: GESNERIACEAE 181
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