COI variation in Georgia's freshwater crayfish 

NSF fellow: Valeria Enseñat-Rivera, Georgia Southern University

Mentor: Dr. Scott Harrison and Dr. Checo Colon-Gaud

Georgia has a substantial diversity of crayfishes, containing over 30 species in the genus Procambarus alone. As highly endemic organisms, many of the species found in Georgia river basins occur nowhere else in the world; however, little is known about their ecology and distribution. This project used genetic techniques to identify crayfish species, primarily by assessing the variation of the mitochondrial Cytochrome Oxidase I (COI) genes present in specimens collected in various river basins within the Atlantic Coastal Plain. Crayfish were collected from the Savannah, Canoochee, Ogeechee, and Altamaha River basins, as well as from Sapelo Island using passive (e.g., baited minnow traps) and active sampling techniques (e.g., dip nets and kick nets). Tissue samples were extracted from tail muscle and the presence of genetic material was quantified using the NanoDrop spectrophotometer. Polymerase chain reaction (PCR) was used to isolate and amplify a 600bp fragment of the COI gene which was subsequently sequenced. The sequences obtained were matched with those on the NCBI database and used in phylogenetic analysis with sequences of known species. The project contributed new information regarding the variation of COI genes, distribution, and phylogeny of crayfish species in the genus Procambarus that inhabit Georgia's Southeastern Coastal Plain.