Finding
Comparison with other carabid taxa shows that 1) the Straits of Florida serve as a potent force delimiting species distributions, 2) speciation in Florida from a southern source is not currently recognized as a general pattern.
Paper
Univariate Analysis of Multivariate Data to Evaluate Circular Overlap in the Agonum decorum Complex (Coleoptera: Carabidae)
Abstract
Agonum decorum (Say) and A. elongatulum (Dejean) are sibling sister species. Discriminant function analysis based on 13 mensural characters was used to ordinate 10 population samples of A. decorum and 7 samples of A. elongatulum . The discriminant function scores on function 1 were analyzed using the simultaneous test procedure UNIVAR algorithm. Results support circumscription of A. elongatulum as a peninsular Floridian species and A. decorum as a wide-ranging species found throughout North America, Mexico, and the Greater Antilles. Morphometric, electrophoretic, and ecological preference data support the hypothesis that A. elongatulum arose as a peripheral isolate of A. decorum , which colonized Florida from an Antillean source during the Pleistocene. Present distributions indicate that this complex represents a case of circular overlap with speciation. Comparison with other carabid taxa shows that 1) the Straits of Florida serve as a potent force delimiting species distributions, 2) speciation in Florida from a southern source is not currently recognized as a general pattern.
Authors
J. Liebherr
Journal
Annals of The Entomological Society of America