80 
John E. Cooper and Martha Riser Cooper 
Variations and anomalies — Individual variation in a number of 
characters is common, but no consistent hydrologic or geographic pat- 
terns are evident. Significant meristic and proportional variations are 
addressed in the “Diagnosis,” but others also require notation. The 
distomedian eminence on the ventral surface of the carpus of the cheliped 
varies in development from a broad, rounded tubercle (rarely) to the 
usual prominent, acute spine that often is as long as the lateral and 
mesial spines of the podomere. Most individuals have a single cervical 
spine on each side of the carapace, but in 8.9 percent of 123 specimens 
there are 2 spines per side, and some animals have a single spine 
on one side and 2 on the other. One form I male has a tubercle 
and 2 spines on the left, 3 spines on the right. In some individuals, 
one or another of the cervical spines is bifurcate, and one female 
has two bifurcate spines on each side. In the same female, the right 
eye was yellow in life, and there are 3 spines instead of the normal 
2 in each caudolateral corner of the cephalic section of the telson. 
There is also variation in the latter character in other specimens, but 
only one other individual, a form I male, has 3 spines in each corner. 
Small hepatic spines or spiniform tubercles are present in 6 of 123 
specimens. One form I male shows a congenital lack of marginal 
spines on the rostrum, and in the same animal the mesial process 
of the left gonopod has a very acute tip with a minute notch in its 
caudal surface. Another form I male has a full-sized but deformed 
antennal scale projecting at nearly 90 degrees dorsally from the base 
of the normal left antennal scale. One female has a copulatory hook 
on the ischium of one of the third pereiopods. 
The fingers of the chela of females and form II males are essentially 
contiguous throughout their lengths when closed, but in form I males 
the fingers gape in the proximal half, and the proximal one-third of 
the opposable margin of the dactyl is moderately excised. In dorsal 
aspect, the central one-third of the dactyl in form I males is gently 
concave, then strongly recurved. In females, a single row of denticles 
extends distally along the opposable margin of the dactyl to the base 
of the cornified tip. In form II males there are one or two such rows 
of denticles, and in form I males there are three or four rows. The 
antennae of form I males are slightly longer than those of form II 
males and females. 
Size — The largest specimen in our samples is a form I male of 
34.1 mm TCL (23.6 mm PCL). Only eight other adult males have 
TCLs in excess of 30 mm. The smallest form I male measures 15.8 
mm TCL (10.8 mm PCL). Lourteen other form I males have TCLs 
of less than 20 mm, and the mean of 55 form I males is 24.6 mm. 
