Branchiopod and Malacostracan Crustaceans 
15 
Also, there are several undescribed species of Camptocercus in the 
United States (Fitzpatrick 1983). As pointed out by Hann (1982), to 
distinguish Eurycercus vernalis from the closely related sibling species 
E. longirostris, one must examine the anatomy of individuals of various 
ages within a population; I did not do this. Nevertheless, the refuge is 
within the presently recognized range of E. vernalis (North Carolina to 
Louisiana) and a considerable distance from that of the sibling E. 
longirostris (Indiana). Frey (1982a) has recently mentioned species in 
the southern United States in particular when commenting on the 
present systematic confusion within several cladoceran groups. He states 
that the cladoceran fauna of the southern United States consists of 
several undescribed species, many possibly constituting species pairs 
with non-conspecific populations having the same name in the northern 
part of the country. 
With the above caveats in mind, I have determined that the 25 
cladoceran species collected in the study include 14 not previously 
reported from South Carolina (Table 1). All 14 species are found 
virtually throughout North America except for E. vernalis (as described 
above), Pseudosida bidentata (largely restricted to the southern states; 
Fitzpatrick 1983), and Monospilus sp. The only species of Monospilus 
previously reported from North America is M. dispar, which is known 
only from the northern United States and Canada (Fitzpatrick 1983). 
The species from the refuge differs from M. dispar primarily in the 
shape of the labrum. Another possibly undescribed refuge species is 
Alona cf. A. guttata , specimens of which differ slightly, but probably in 
a taxonomically significant manner, from those of A. guttata Sars in 
having a distal expansion of the postabdomen. 
Isopods 
There are three common aquatic isopod species ( Caecidotea forbesi , 
C. laticaudata , Lirceus lineatus) at the refuge and one very rare species 
(C. obtusa)\ the rare species was found during both winters, but only in 
Dingle Pond. Of these species, C. forbesi was the one most commonly 
encountered throughout the refuge and throughout the year. Caecidotea 
forbesi was most widely distributed from winter into early summer, with 
occurrences decreasing during late summer and fall (Table 2). This 
species was most abundant when the water was cool, either during the 
winter at many sites or throughout the year at some shaded locations, 
such as shallow forest swamps and shaded ditches. Although C. forbesi 
was found in a wide variety of habitats, it was largely restricted to 
shallow, shaded areas and was rarely found in impoundments. At 
locations where the only species of Caecidotea collected was C. forbesi 
(based on identification of males), brooding females were found in all 
