| Abstract | Dicerandra (Lamiaceae) comprises nine species (Dicerandra christmanii, Dicerandra
cornutissima, Dicerandra densiflora, Dicerandra frutescens, Dicerandra fumella, Dicerandra
immaculata,Dicerandra linearifolia, Dicerandra modesta, Dicerandra thinicola, Dicerandra
radfordiana) endemic to the southeastern United States. Species of Dicerandra are threatened
or endangered and restricted to sand hill vegetation and a mosaic of scrub habitats, with some
species (D. cornutissima, D. thinicola, D. immaculata, D. frutescens, D. christmanii, and D.
radfordiana) being restricted to one or two sites in peninsular Florida and Georgia. Using locality
and specimen data from iDigBio and other sources, we have applied ecological niche modeling
to investigate shifts in abiotic niche space among species. Such shifts may have served as
isolating mechanisms associated with speciation. These results will be used to reconstruct
ancestral niche spaces when sea levels and climate were markedly different. We will make
inferences on the possible ecological shifts and niche diversifications associated with speciation
that have occurred during the evolution of the genus |
