30 
John R. Holsinger and David C. Culver 
Order Isopoda 
Isopods are represented in the regional cave fauna by three 
suborders: Asellota, Flabellifera, and Oniscoida. All asellotids from 
caves in Virginia and eastern Tennessee are in the large, Holarctic, 
freshwater family Asellidae. Flabelliferans are represented by a single, 
unique member of the predominantly marine family Cirolanidae. 
Oniscoids are terrestrial and are represented by the families Arma- 
dillidiidae, Ligiidae, Oniscidae, and Trichoniscidae. 
Cavernicolous asellids are usually associated with the gravel or 
rock substrate of small streams or the mud-bottom substrate of drip/ 
seep pools. Some species apparently prefer riffle zones, whereas others 
are sometimes seen in large concentrations on flowstone surfaces covered 
by thin films of moving water (see Culver 1973a, Estes and Holsinger 
1982). Two genera, Caecidotea and Lirceus , occur in study-area caves. 
The former is represented by 1 1 species, 9 of which are troglobites; the 
latter is represented by two species (both troglobites) and possibly 
several undescribed (non-troglobitic) ones as well (see Henry et al. 
1986). 
Although several troglobitic species of Caecidotea have relatively 
wide ranges, their distributions generally correspond rather closely to 
drainage basins (Fig. 11, 12). Some of the wide-ranging species, such as 
C. richardsonae, C. recurvata , and C. pricei , have also been collected 
occasionally from subterranean waters outside caves (e.g., seeps, wells). 
Five species, viz., C. holsingeri, C. incurva , C. recurvata (Fig. 13C), C. 
richardsonae , and C. pricei , have ranges that extend beyond the study 
area, whereas C. bowmani , C. henroti , and the undescribed species from 
Cliff Cave (Lee County) are local endemics with very restricted ranges. 
Of particular interest here is C. bowmani , at present known only from a 
drain-tile habitat in Rockbridge County (see Lewis 1980). Although this 
species is not recorded from a cave per se, it is of troglobitic facies and, 
with careful searching, will possibly be found in caves. Because of this 
we have listed it as a troglobite. Moreover, careful reevaluation of 
collections from caves in the James River basin previously assigned to 
C. vandeli by Fleming (1972) may very well result in their reassignment 
to C. bowmani. 
Because taxonomic studies of Caecidotea have placed almost 
complete emphasis on the morphology of the male second pleopod and 
tended toward the “lumping” of species, a careful reevaluation of the 
systematics of the Appalachian cave species is warranted. In support of 
this view is the recent research by J. J. Lewis (in progress) on the 
systematics of subterranean Caecidotea of the east-central United States, 
which has revealed additional new species from material previously 
assigned to described taxa. Based on geographic distribution and ecology, 
we suspect that C. richardsonae , for example, can; with careful 
