1967] 
Barr — New Pseudanophthalmus 
171 
inhabit caves in close proximity to mountains 1000 to 1300 meters 
high. 
The current view of extrinsic isolation in different cave systems 
(Barr, 1965; Krekeler, 1959; see also Barr, in press) assumes that 
dispersal of troglobites from one system to another can take place 
only via subterranean routes, so that caves in limestone outcrops 
separated by non-caverniferous elastics (as in the Appalachian valley) 
are thought to represent habitats between which gene flow cannot 
take place. Once a species becomes a troglobite, its geographic dis- 
tribution is controlled by its ability to disperse through subterranean 
channels and crevices, which are far more prevalent in soluble rocks 
than in elastics. It must be stressed that the discovery of P. sylvaticus 
does not basically change this view. For the moment, it appears that 
edaphic Pseudanophthalriius spp. in the United States are rare and 
probably restricted to cold mountain forests in a relatively few 
favorable places. Certainly the prevalence of such species needs fur- 
ther investigation. 
On the other hand, the occurrence of P. sylvaticus supports the 
theory that cave Pseudanophthalmus spp. are relicts of rather widely 
distributed populations of edaphobites which existed near glacial 
margins and which colonized (and survived in) various cave systems 
during the early stages of interglacials. The peculiar occurrence of 
P. illinoisensis (Barr and Peck, 1966) in Hardin Co., Illinois, 175 
kilometers west of all other known species of the tenuis group, which 
inhabit southern Indiana and adjacent Kentucky, is understandable 
in these terms. P. illinoisensis is so similar to P. barberi Jeannel, 
from the Pennyroyal Plateau of Kentucky between Mammoth Cave 
and the Ohio River, that the two species almost certainly share a 
close common ancestry, yet they are separated by the Ohio River 
and more than 150 kilometers of terrane underlain by sandstones, 
shales, and coals. A similar, though less spectacular case involving 
a pair of undescribed species of the menetriesi group in Tennessee 
and Kentucky is under study; a widespread, polytypic species inhab- 
iting caves of the upper Cumberland and Green River drainages is 
separated from a closely similar form inhabiting a single cave near 
the center of the Central Basin. 
Literature Cited 
Barr, Thomas C., Jr. 
1964. The status and affinities of Duvaliopsis Jeannel (Coleoptera: 
Carabidae). Psyche, 71 (2): 57-64. 
