Pseudotremia ryensis, Shear, William A., 2011

Shear, William A., 2011, Cave millipeds of the United States. X. New species and records of the genus Pseudotremia Cope. 2. Species from Virginia, USA (Diplopoda, Chordeumatida, Cleidogonidae), Zootaxa 3109, pp. 1-38 : 24-27

Pseudotremia ryensis , n. sp.

Figs. 72–77

Types: Male holotype, male and female paratypes from Franklin Cave, Rye Cove, Scott Co., VIRGINIA, collected 23 March 2005 by C. S. Hobson and W. Orndorff.

Diagnosis: Among highly adapted troglobionts, this species can be compared with P. nodosa , but differs in details of the gonopods. In P. nodosa , the MAPs have the subapical spine developed as a short, medially directed triangular process, while this is completely absent in ryensis . Pseudotremia ryensis lacks any median colpocoxite processes, but in nodosa there is a short ventral process. The ninth legs of ryensis are also diagnostic, with two very large ventral median knobs and short distal segment.

Etymology: Since this species appears to be confined to the caves of Rye Cove, the specific epithet is a Latinized adjective reflecting that fact. Suggested vernacular name: Rye Cove Cave Milliped.

Description: Male holotype about 16 mm long, 1.4 mm wide, third antennal segment 0.85 mm long. Ocelli 10 on each side of head, variable in size, well-separated, poorly pigmented (fig. 73). Segmental shoulders low, metazonites nearly smooth, two or three poorly indicated low rugae at posteriolateral corners (fig. 74); four or five mostly incomplete lateral striations. Color pale tan anteriorly with light brown mottlings, fading to white posteriorly.

Gonopods (figs. 75, 76) reduced, simple; angiocoxites roughly parallel, distally diverging, MAPs lacking spines; LAPs short, simple, gently curved, entire. Colpocoxites fused for most of their length, then sharply diverging, not mitten-shaped but with two low, apical lobes (fig.); median colpocoxite processes absent. Ninth legs (fig. 77) distinctive, apical article very short, coxoprefemur not distally swollen, with two large, blunt ventral lobes.

Female similar to male.

Additional records: All from VIRGINIA: Scott Co.: Rye Cove. Flannery Cave, 26 May 2004, C. Hobson, W. Orndorff, A. Chazal, S. Hanlon, juvs.; McDavid’s Cave, 25 May 2004, C. Hobson, W. Orndorff, C. Robbins, 3 ƤƤ; 3 August 1974, J. Holsinger, D. Culver, 3 ƤƤ; Thatcher Fissure, 16 May 2005, C. Hobson, C. Zokoites, 3; Rigg’s Chapel Cave, 24 May 2004, C. Hobson, juvs. presumably this species.

Notes: Rye Cove is a synclinal valley, or “garden” in which a floor of Ordovician limestone has been exposed and which is extensively cavernous ( Orndorff 2003). Most of the underground drainage of the valley surfaces in Mill Creek Springs, near its southern margin, and the Rye Cove Cave Isopod, Lirceus culveri Estes & Holsinger 1976 , is found in this drainage. This isopod is listed as vulnerable on the IUCN Red List, and such a listing may be considered for Pseudotremia ryensis , which, due to its rather high degree of troglobiosis, is surely cave-limited. At its type locality and probably in other caves in Rye Cove, this species is syntopic with Pseudotremia hobbsi , a troglophile.

Figures

FIGURES 67 – 72. New species of Pseudotremia. Figs. 67 – 71, Pseudotremia hubbardi, n. sp. Fig. 67, ocelli. Fig. 68, metazonite, dorsal view. Fig. 69, gonopods, anterior view; cc, colpocoxites; lap, lateral angiocoxite process; map, median angiocoxite process. Fig. 70, gonopods, lateral view. Fig. 71, gonopods, ventral view; cc, colpocoxites. Fig. 72, P. ryenesis, n. sp., metazonite, lateral view.

FIGURES 73 – 79. New and previously described species of Pseudotremia. Figs. 73 – 77, Pseudotremia ryensis, n. sp. Fig. 73, ocelli. Fig. 74, diplosegment, dorsal view. Fig. 75, gonopods, ventral view. Fig. 76, gonopods, anterior view. Fig. 77, right ninth leg, anterior view. Figs. 78, 79, P. n o d o s a. Fig. 78, right ninth leg, anterior view. Fig. 79, metazonite, lateral view.