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 Etowah River System

1a. Claws with red or orangish tubercles...........Procambarus clarkii
1b. Claws without red or orangish tubercles...........................go to 2

2a. Two cervical spines (Fig. 1A)................Procambarus spiculifer
2b. One or zero cervical spines (Fig. 1B)...............................go to 3

cervical spines

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

3a. Single, well developed, sharp cervical spine (Fig. 1B).......go to 4
3b. At most single cervical tubercle, or nothing........................go to 7

4a. Claws gaping when fingers closed, rostrum tapering somewhat
and appearing almost “pinched” in the middle; found almost
exclusively above Allatoona Dam. (Fig. 2A).......Cambarus fasciatus
4b. Claws not gaping when fingers closed (Fig. 2B); (claw of large Cambarus coosae may be gaping somewhat but this species found
only below Allatoona Dam)...................................................go to 5

claw gape

Figure 2. Dorsal view of crayfish claws indicating A) gaping and B) non-gaping condition.  Modified from Hobbs (1981).

5a. Lateral edge of claw black, black spot on palm at base of
moveable finger................................................Orconectes spinosus
5b. No black pigment present on claws....................................go to 6

6a. Overall fairly brightly colored with light orange, brown, green, and bluish hues; rostral margins reddish; cervical spine always well developed (sharp) and reddish in color; areola broad, almost
appearing parallel-sided.........................................Cambarus coosae
6b. Overall drab colored, tan to brown with darker brownish mottling; rostral margins not brightly colored; cervical spine well-developed
and sharp only in smaller individuals and never red in color; areola
narrower, hourglass-shaped..................Cambarus latimanus, in part

7a. Spine extending past edge of uropod
(Fig 3A)..........................................................Cambarus acanthura
7b. Spine not extending past edge of uropod (Fig. 3B).............go to 8

tails web

Figure 3. Position of spine on mesial ramus of uropod.  A) Spine extending past edge of uropod; B) spine not extending past edge of uropod.  Modified from Hobbs (1981).

8a. Claws with single row of tubercles along mesial margin of palm
(Fig. 4A)................................................Cambarus conasaugaensis
8b. Claws with at least two rows of tubercles along mesial margin
of palm (Fig. 4B)..................................................................go to 9

jug dep claws web

Figure 4. Dorsal view of crayfish claws indicating A) single row of tubercles along mesial margin of palm and B) more than one row of tubercles along mesial margin of palm.  Modified from Hobbs (1981).

9a. Areola usually more than 9 times as long as broad; rostrum
typically somewhat blunt (Fig. 5A); some populations with distinct abdominal stripes; cervical spines never present....Cambarus striatus
9b. Areola usually less than 9 times as long as broad; rostrum
tapering (Fig 5B); some individuals with indistinct abdominal stripes;
cervical spines sometimes present, especially in
juveniles...........................................................Cambarus latimanus

striatus latimanus dorsal web

Figure 5. Dorsal view of A) Cambarus striatus showing typically narrower areola than areola of B) Cambarus latimanus.  Modified from Hobbs (1981).

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