Crayfishes of Georgia
Crayfishes of Georgia Overview List of Georgia Species Species Lists by Drainage Crayfish Identification Keys by Drainage Ecology and Life History Links and Other Useful Information Glossary
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Dichotomous Key to the Crayfishes of the Ohoopee River System

1a. Two cervical spines (Fig. 1)..................Procambarus spiculifer
1b. One or zero cervical spines...........................................go to 2

 cervical spines

Figure 1. Lateral view of crayfish indicating number and position of cervical spines. Modified from Hobbs (1981).

2a. Mesial margin of palm longer than moveable
finger..............................................................Faxonella clypeata
2b. Mesial margin of palm shorter than moveable finger......go to 3

3a. Claw tubercles reddish or orangish........Procambarus howellae
3b. Claw tubercles not reddish or orangish............................go to 4

4a. Greatest width of palm greater than length of mesial margin of palm...................................................................................go to 5
4b Greatest width of palm less than length of mesial margin of palm (sometimes about equal in females.......................................go to 6

 advena truculentus web

Figure 2. Left gonopods of A) Form II, Procambarus advena; B) Form I, P. advena; C) Form II, P. truculentus; D) Form I, P. truculentus. Modified from Hobbs (1981).

5a. Male gonopod hatchet shaped (Figs. 2C, D); rostrum broad, spatulate...............................................Procambarus truculentus
5b. Male gonopod not hatchet shaped (Figs. 2A, B); rostrum
narrower, pointed........................................Procambarus advena

6a. Dorsal surface of rostrum with dense
setae.........................................................Procambarus pubescens
6b. Dorsal surface of rostrum with at most, scattered setae.....go to 7

7a. Areola wide, less than 8 times as long as broad...............go to 8
7b. Areola narrower, averaging greater than 8 times as long as broad.............................................................Procambarus acutus

8a. Rear of carapace with dorsal saddle which usually extends
forward as “horns”; sometimes the horns may be broken into two spots.................................................Procambarus enoplosternum
8b. Rear of carapace without dorsal saddle; two discrete spots
on upper sides of carapace.........................Procambarus seminolae

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