﻿A NEW CRAYFISH FROM ALABAMA — PIOBBS 217 



Tyjie locality. — A tributary of Calebea Creek [Alabama River sys- 

 tem], 3.9 miles south of Tuskegee, Macon County, Ala., on United 

 States Highway 29. The specimens on which this description is 

 based were collected by Dr. E. C. Raney, of Cornell University, on 

 March 24, 1948, and he has kindly furnished me with the following 

 data : At this locality the stream is clear, about 10 feet wide and 3 

 feet deep, sandy-bottomed, and with a volume flov»- of 5 cubic feet per 

 second. The stream flows through an open })asture, and at the time 

 the collection was made the temperature of the air was 80° F., and 

 (hatof the water 65° F. 



Disposition of types. — The holotypic male, form I, allotypic female, 

 and morphotypic male are deposited in the United States National 

 ISIuseum (No. 90743). The paratypes, consisting of one male, form 

 I, one male, form II, and one female, are in my personal collection at 

 the University of Virginia (No. 3-2448-3b). 



Relationships. — Procamharus verrucosus^ a member of the Bland- 

 ingii group (Hobbs, 1942b, p. 341), has its closest affinities with Pro- 

 camharus hlandingii acutus (Girard, 1852, p. 91). However, it may 

 readily be distinguished from it by the more complexly appearing 

 annulus ventralis of the female, and the structure of the first pleopod 

 of the male. The caudal Jcnoh of the first pleopod has assumed a 

 markedly different position in P. verrucosus from that in some of the 

 other species of this group, in which this knob more closely resembles 

 that of the hypothetical generalized pleopod (Hobbs, 1942a, p. 58). 

 In P. hayi (Faxon, 1884, p. 108) the caudal knob (which has been 

 prolonged proximally into a long irregular fold) lies on the caudo- 

 lateral face of the appendage at the base of the caudal process; in 

 P. hlandingii acutus., while the caudal knob is distinctly knoblike, it 

 has shifted caudolaterad and lies at the cephalolateral base of the 

 cephalic process ; in P. verrucosus there has been a still stronger degree 

 of shifting in a cephalic direction so that it forms a rounded shoulder 

 on the cephalic border of the appendage. Were it not for the in- 

 termediate stages of shifting of the "caudal knob" which have been 

 observed in specimens tentatively identified as P. hlandingii acutus 

 (a subspecies that has never been clearly defined) one would hardly 

 suspect that the "shoulder" on the pleopod of P. verrucosus had any 

 relationship to that of the more "typical" caudal knob as occurs in 

 P. picfus (Hobbs, 1940, p. 419) and the "less typical" one in P. hayi. 



Remarks. — The annulus ventralis of the allotype contains a sperm 

 plug, which indicates that this species breeds in the early spring; 

 however, it should be pointed out that this does not mean that this 

 species does not breed during summer, fall, or winter. 



