Tropical Biology Section
Ballard, H. E. , DeMuria, J. .
Revisionary systematics of the tree-violets (Rinorea) of tropical Asia and the South Pacific.
We conducted revisionary systematic studies of several large collections of the genus Rinorea from tropical Asia and the South Pacific (BM, K, L and MO) with a narrow, critical morphological species concept to reevaluate species circumscriptions and distinctions of taxa. We utilized a wide range of traits from the inflorescence, flower and fruit, including overlooked features of the capsule, to delineate nine species complexes. Further scrutiny of species complexes revealed two to several morphologically uniform and geographically coherent morphotaxa recognizable as species or infraspecific taxa. Most taxa diverged in several vegetative and reproductive features and were recognized at the species level. A few additional taxa shared the bulk of features with other populations geographically separated from them and were retained as subspecies. Our comprehensive studies have distinguished 27 well-defined morphological species, as well as two additional subspecies in Rinorea hookeriana (King) Burkill (a resurrected name) and a third in R. cinerea (described previously), as compared to 11 by Jacobs and Moore (1971) and a few additional new species in the last 15 years. We resurrected some older names, maintained all recently published ones by Forman (1996), Jarvie and Stevens (1998) and Stevens (2000), and we are describing three new narrowly endemic species and one widespread subspecies. Most resurrected taxa were segregated from the Bengalensis and Javanica complexes, previously circumscribed by Jacobs and Moore as two polymorphic species with huge numbers of synonyms. Our studies of Rinorea reject such overly broad circumscriptions as untenable and instead recognize several consistently distinguishable species in each. Our reexamination of the genus has revealed much greater species diversity in the region than previously believed. Our results urge similar systematic reevaluation of other angiosperm groups in Southeast Asia and the South Pacific using a more narrow and critical morphological species concept.
Log in to add this item to your schedule
1 - Ohio University, Department of Environmental & Plant Biology, Porter Hall, Richland Avenue, Athens, Ohio, 45701-2979, USA
2 - Ohio University, Center for International Studies, Athens, Ohio, 45701, USA
Presentation Type: Oral Paper:Papers for Sections
Date: Monday, July 28th, 2008
Time: 4:00 PM