An eyeless subterranean beetle (Pseudanophthalmus) from a Kentucky coal mine (Coleoptera:Carabidae:Trechinae).
Psyche 93:47-50, 1986.
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AN EYELESS SUBTERRANEAN BEETLE
FROM A KENTUCKY COAL MINE
(COLEOPTERA: CARABIDAE: TRECHINAE)*
School of Biological Sciences,
University of Kentucky
Lexington, Kentucky 40506
The trechine genus Pseudanophthalmus includes approximately 240 species from caves of the Appalachian valley, Mississippian plateaus, and Bluegrass and Central Basin regions of eastern United States. Although the model of cave trechine speciation which I have developed for this fauna (Barr, 1967a, 1968, 1981, 1985) requires a two-step process of 1) local diversification in deep soil and 2) subse- quent isolation in nearby caves, the first stage was postulated on the basis of an abundant edaphobitic trechine fauna in Europe and elsewhere (see Jeannel, 1926-1930, for example). In eastern United States a single species of Pseudanophthalmus has been described from a non-cave habitat: P. sylvaticus occurs deep in the soil under large stones in mountain forests near Marlinton, West Virginia (Barr, 1967b).
Existing distributions of cave Pseudanophthalmus species strongly suggest an ancestral Pleistocene refugium in the mixed meso- phytic forests of the Allegheny plateau (Barr, 1981, 1985). The dis- tinctly different lineages occupying caves of the Appalachian valley to the east of the plateau and those of the Interior Low Plateaus to the west of the Alleghenies indicate substantial local differentiation prior to cave colonization (Barr, 198 1); the geographic clustering of related species suggests vicariance among cave descendants of these locally differentiated edaphobites (Barr, 1965, 1981, 1985). An integrated phylogeny of Pseudanophthalmus has thus far proven elusive, as though key pieces of a jigsaw puzzle were missing. Preliminary track analysis at the species group level thus shows a *Manuscript received by the editor December 15, 1985 Pzirfif 93:47-SO (1986). hup Ylpq'chi: rnlclub org╠÷3/93-047.htm
19861 Barr-Subterranean beetle 49
in Floyd County, eastern Kentucky. The mine portal, designated "D-104" in MacGregor's notes, is located at Bosco (= Hueysville), about 22 km SSW Prestonsburg. The beetles were found in a muddy spot on the mine floor under rocks.
These two females are identical with females of Pseudanophthal- mus hypolithos (Barr, 198 1: 83, figs. 28, 34), a species previously known only from Old Quarry Cave, in Pine Mountain, near Ash- camp, Pike County, Kentucky, 45 km SE of the Bosco mine. The hypolithos group, which includes 4 species from Pine Mountain, KY, and a single species (P. praetermissus) near the base of Cumber- land Mountain in Scott County, VA, belongs to the engelhardti complex, a group of 55 largely Appalachian valley species arranged in 7 species groups (Barr, 1981). Pseudanophthalmus hypolithos, itself, is distinguished from other species of the group by quite deep elytral striae and convex elytral intervals, greatly reduced pubes- cence limited chiefly to sparse and very short rows on each elytral interval, and falciform aedeagal apex. The aedeagal character could not be checked, but based on my experience with species of the genus, the absence of non-genitalic differences is decisive; only 2/240 species are determined solely on male genitalic characters. Previously I had considered Pine Mountain as a "karst island" within the Allegheny plateau; it is a fault block about 125 km long, extending from Elkhorn City, Kentucky, southwest to Campbell County, Tennessee, with a band of Newman limestone (Mississip- pian) exposed on its northwest face. To the extent that "troglobitic" Pseudanophthalmus species are collectable within the caves of Pine Mountain, this is still true after a fashion, but the discovery of P. hypolithos in a coal mine indicates that "caves" are a somewhat artificial concept in terranes where highly fractured rocks (shales, coals, conglomerates) exist, and that "troglobitic" trechines may occur over a wider area than is strictly delimited by karst terrane. The Bosco mine offers another sort of entry into the deep soil com- munity, and the discovery of P. hypolithos there is a strong impetus to search for other edaphobitic trechines within the interior of the Allegheny plateau.
I thank John R. MacGregor for making these specimens available for study. This paper was supported in part by NSF DEB-8202339.
BARR, THOMAS C., JR.
The Pseudanophthalmus of the Appalachian valley (Coleoptera: Cara- bidae: Trechini). Amer. Midi. Nat. 73: 41-72. 1967a. Observations on the ecology of caves. Amer. Nat. 101: 475-492. 1967b. A new Pseudanophthalmus from an epigean environment in West Vir- ginia (Coleoptera: Carabidae). Psyche 74: 166- 174. 1968.
Cave ecology and the evolution of troglobites. Evolutionary Biology 2: 45-102. Appleton-Century-Crofts, New York. 1981.
Pseudanophthalmus from Appalachian caves (Coleoptera: Carabidae): the engelhardti complex. Brimleyana, no. 5: 37-94. 1985.
Pattern and process in speciation of trechine beetles in eastern North America (Coleoptera: Carabidae: Trechinae). IN G. E. Ball, ed., Taxon- omy, Phylogeny, and Zoogeography of Beetles and Ants. Dordrecht, Netherlands: Dr. W. Junk Publishers.
1926- 1930. Monographic des Trechinae: Morphologie comparke et distribu- tion d'un groupe de Colkoptkres. L'Abeille 32: 221-550; 33: 1-592; 34: 59-122; 35: 1-808.
JUBERTHIE, C., B. DELAY, AND M. BOUILLON 1980. Extension du milieu souterrain en zone non-calcaire: description d'un nouveau milieu et de son peuplement par les Colkoptkres troglobies. Mkm. Biospkol. 7: 19-52.
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