Summary
The Pascagoula map turtle, Graptemys gibbonsi (Family Emydidae), is a large aquatic species endemic to the Pascagoula and Pearl River drainages of Mississippi and southeastern Louisiana. It was previously considered part of the composite species G. pulchra. Sexual dimorphism is pronounced, with adult females (carapace length to 295 mm) attaining more than twice the size of adult males (to 141 mm). Although the species is locally abundant, populations are threatened by habitat destruction, commercial collecting, and target practice by unethical people who shoot basking turtles. The current IUCN Red List status is Lower Risk/Near Threatened, but the status should be re-examined due to recent surveys indicating population declines or the disappearance of the species from previously documented localities. In addition, genetic and pattern differences between populations in the Pearl and Pascagoula rivers suggest that the two entities should be managed separately to protect significant biodiversity.
Distribution
USA. Restricted to the Pascagoula and Pearl River systems of Mississippi and Louisiana, as well as the lower Escatawpa River of southeastern Mississippi.
Distribution of Graptemys gibbonsi in the southeastern USA (Louisiana and Mississippi). Red points = museum and literature occurrence records based on Iverson (1992) plus more recent and authors' data; green shading = projected distribution based on GIS-defined hydrologic unit compartments (HUCs) constructed around verified localities and then adding HUCs that connect known point localities in the same watershed or physiographic region, and similar habitats and elevations as verified HUCs (Buhlmann et al., in press), and adjusted based on authors' data.
Synonymy
Graptemys gibbonsi Lovich and McCoy 1992, Graptemys pulchra gibbonsi.
Subspecies
None recognized.
Conservation Status
IUCN 2008 Red List Status: Lower Risk / Near Threatened (LR/NT) (assessed 1996, needs updating)
Legal Status
CITES: Appendix III (all Graptemys spp.; USA); US ESA: Not Listed.
Citation
Lovich, J.E., Selman, W., and McCoy, C.J. 2009. Graptemys gibbonsi Lovich and McCoy 1992 – Pascagoula map turtle, Pearl River map turtle, Gibbons' map turtle. In: Rhodin, A.G.J., Pritchard, P.C.H., van Dijk, P.P., Saumure, R.A., Buhlmann, K.A., Iverson, J.B., and Mittermeier, R.A. (Eds.). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs No. 5, pp. 029.1-029.8, doi:10.3854/crm.5.029.gibbonsi.v1.2009, //iucn-tftsg.org/cbftt/.