Scoterpes tombarri, Shear, 2010

Shear, William A., 2010, 2385, Zootaxa 2385, pp. 1-62 : 50

Scoterpes tombarri , n. sp.

Figs. 75, Map 5

Types: Male holotype and male and female paratypes ( FSCA) from Plano Saltpetre Cave , 20 mi S of Bowling Green, Warren Co., Kentucky, collected 18 June 1973 by S. B. Peck .

Diagnosis: Most similar to S. hesperus , n. sp., but differing in the longer, more bladelike median angiocoxites and the slightly branched anterior processes of the lateral angiocoxites; the fimbriate branches of the colopocoxites generally appear smaller, but this character is variable.

Etymology: Named for Thomas C. Barr, dean of American speleobiologists, professor emeritus at the University of Kentucky, and author of Caves of Tennessee.

Description of male from Plano Saltpetre Cave: Length, 10.0 mm, width, 0.95 mm. Nonsexual characters typical of genus. Gonopods ( Fig. 75) with coxae loosely fused to sternum; distal setal group clumped on obvious lateral shoulder, about 6 or 7 setae, single isolated seta near base; proximal group mesal, 3 setae. Medial angiocoxite narrow, bladelike, acute; lateral angiocoxite slightly folded apically, with anteriorly projecting branch bearing several small, acute subbranches, seen in anterior view longer, thinner than in S. musicarustica . Colpocoxite fimbriate branches linear, strongly fringed apically and along length. Ninth legs as usual for genus.

Female from Plano Saltpetre Cave: Length, 11.0 mm, width 1.0 mm. Nonsexual characters as in male.

Distribution: See Map 5 for selected records. All specimens FSCA; all records supported by at least one male. KENTUCKY: Logan Co. Collier Cave, 25 June 1957, T. C. Barr; Cooks Cave, 25 June 1957, T. C. Barr; Mud River Cave, 3 August 1967, collector unknown. Simpson Co. Hoy Cave, 2 mi N of Franklin, 2 January 1958, T. C. Barr. Todd Co.: Glover Cave, 9 June 1957, T. C. Barr. Trigg Co. Hardy Cave, 3 mi SSW Caledonia , 12 August 1965, T. C. Barr, J. Holsinger. Warren Co. Horseshoe Cave, 17 August 1963, T. C. Barr. TENNESSEE: Robertson Co. Buzzard Cave, 16 August 1957, T. C. Barr. Stewart Co. Tobaccoport Saltpetre Cave, 16 July 1957, T. C. Barr.

Notes: Yet another species of the Copei Group, Scoterpes tombarri was assigned the name “barri” on labels by Nell Causey, though later she relabeled some specimens as “ventus barri.” The region of Kentucky where this species is found is the western part of the Cumberland Plateau (sensu lato) referred to in Tennessee as the Western Highland Rim; in Kentucky it is called the Pennyroyal Plateau, “Pennyrile (by local inhabitants),” or more formally the Mississippian Plateau. The distribution of S. tombarri is separated from that of S. copei on the east by the Barren River, and from that of S. musicarustica on the south by the Cumberland River, although additional collecting will be required to definitively establish that these rivers are actually barriers.

It is interesting that this species and a population of S. copei were examined using electrophoretic techniques ( Laing, Carmody & Peck 1976). Scoterpes tombarri was sampled from State Trooper Cave, Bowling Green, Warren Co., Kentucky, and S. copei from White’s Cave, Mammoth Cave National Park, Hart Co., Kentucky. The two caves are separated by about 43 km and as stated above, by the Barren River. At the time, Laing et al (1976) assumed that both populations represented S. copei . Unfortunately no voucher specimens were kept, and I have seen no additional specimens from State Trooper Cave, but I am quite sure that the geography of the situation supports the hypothesis that S. tombarri would be found in that cave. The results of the electrophoretic study showed that of the 10 loci that could be measured, six had become fixed for different alleles in the two populations, and that at two polymorphic loci, the two populations possessed completely different alleles. The authors concluded the two populations represented two different species (Rogers coefficient of 0.217), and that conclusion is supported here by gonopod morphology.