TyphloelmisBarr (Coleoptera: Elmidae: Elminae), a New Stygobiontic Riffle Beetle Genus with Three New Species from Texas, USA Author Barr, Cheryl B. Author Gibson, J. Randy Author Diaz, Peter H. text The Coleopterists Bulletin 2015 2015-12-31 69 4 531 558 http://dx.doi.org/10.1649/0010-065x-69.4.531 journal article 10.1649/0010-065X-69.4.531 5334774 Typhloelmis finegan Barr , new species ( Figs. 1 , 8 , 12 , 15 , 18 ) Material Examined. HOLOTYPE ♀ in EMEC , labeled “ USA : Texas : Val Verde Co. / Devils River State Natural / Area , Finegan Springs , 405m / 29.9011°,-100.9987°, 25-II- / 2010, J. R . Gibson & P. H. Diaz “ // [genitalia vial] // “ HOLOTYPE Typhloelmis finegan Barr ” [red label, handwritten]. Description. Holotype female. Length 4.1 mm (elytra + pronotum), width 1.2 mm. Cuticle redbrown, barely translucent, with extensive whitish dorsal and ventral plastron; surface smooth, lacking dorsal carinae, striae, and punctures ( Figs. 8 , 12 ). Antenna: Color medium red-brown, antennomeres 1–10 narrowly cone-shaped, wider distally than basally; antennomere 11 narrowly fusiform and acutely pointed ( Figs. 8 , 12 , 15 , 18 ). Head: Color medium red-brown, darker at clypeal margin; surface bearing evenly spaced, small granules and short setae. Eyes absent ( Figs. 12 , 15 , 18 ). Labrum with long, pale setae on distal 1/2. Mandible dark brown with 2 short teeth; upper tooth longest, narrow with blunt tip; lower tooth much shorter and broader. Pronotum: Color dark red-brown, covered with whitish plastron except at anterior margin and antero-medially on disc where abraded ( Fig. 8 ). Longer than wide; length 1.4 mm, width 1.1 mm at widest point just anterior to base ( Figs. 8 , 12 , 15 ). Lateral margins distinctly reflexed; crenulate with small, rounded, evenly spaced teeth; basolateral angles blunt and rounded. Disc with short, sparse setae; small, protuberant granules emergent from plastron adjacent to apicolateral and lateral margins. Elytron: Color dark redbrown, covered with whitish plastron except for at basal margin and suture, and where scratched and abraded medially ( Fig. 8 ). Length 2.7 mm, width 0.6 mm at widest point. Disc with short, sparse setae; widely spaced, small, round granules emergent from plastron, more protuberant laterally; loosely arranged into longitudinal rows more closely spaced laterally. Outer 1/3 of disc in posterior 1/2 wrinkled, with irregular grooves perpendicular to lateral margin. Lateral margin serrate with evenly spaced teeth ( Figs. 8 , 12 ). Leg: Color of coxa, trochanter, femur, and tibia dark red-brown; tarsus medium red-brown. Pro- and mesothoracic legs without plastron, shiny; metathoracic leg with plastron present on coxa, trochanter, and femur, absent on tibia and tarsus. Femur with low granules and fine setae dorsally, flattened and granulate ventrally; pro- and mesofemora with numerous, spinose granules at margins of ventral flattened area; metafemur much less granulate and spinose. Tibia with large granules bearing prominent spines on all surfaces, spines largest, most numerous, at apex ( Fig. 12 ); protibia with spines most well-developed ( Figs. 12 , 15 , 18 ). Tibia of all legs with fringe of long, pale setae (tomentum) on medial surface ( Figs. 8 , 12 ); protibia with tomentum at middle 1/3, meso- and metatibiae with tomentum extending most of length except for at base and apex. Tarsomeres 1–4 with short, stout setae at ventral apex; tarsomere 5 with few setae along length of ventral surface. Claws moderately slender and barely curved. Venter: Color light red-brown, covered with plastron; setae short and sparse. Prosternum ( Fig. 18 ) covered with variably spaced granules; prosternal process narrowly triangular, apex broadly rounded, nearly truncate. Metaventrite ( Fig.12b ) covered with numerous, closely spaced granules; anterior margin truncate between mesocoxae; metakatepisternal suture slightly arcuate, discrimen obvious just anterior to intersection only. Abdominal ventrites ( Fig. 12b ) with widely spaced, low granules and setae; ventrite 1 with granules present on entire surface; ventrites 2–4 with granules present mainly laterad; ventrite 5 with apical 1/2 granulate and setose, with shallow median depression near apex, apex bearing fringe of fine, moderately long setae; intercoxal process of ventrite 1 triangularly shaped, apex acute. Female genitalia: Each longitudinal bacula subequal in length to gonocoxite; stylus short, narrowly ovoid. Median sclerite present between bases of gonocoxites, both dorsally and ventrally. Vagina extruding between the gonocoxites well beyond tips of styli. Variation. Unknown. Diagnosis. Typhloelmis finegan ( Fig. 8 ) is unlikely to be confused with either T. caroline ( Fig. 6 ) or T. sanfelipe ( Fig. 7 ) because it is much larger (length> 4 mm vs. < 3 mm ) and darker colored. In addition, in T. finegan ( Figs. 8 , 12 , 15 , 18 ) the prosternal process is broader, triangular, and not medially constricted; the pronotum is margined with rounded, evenly spaced teeth; antennomeres 1–10 are similarly cone-shaped; the metaventrite is very granulate; the femora are ventrally flattened; the tibia of all legs possesses fringes of tomentum; and protarsomere 5 is not bulbous. In both T. caroline ( Figs. 6 , 9 , 13 , 16 ) and T. sanfelipe ( Figs. 7 , 10 , 14 , 17 ), the prosternal process is narrow and elongate; the pronotal margins have irregular granules or teeth; antennomeres 1–10 are not similarly cone-shaped, and antennomere 2 is larger than all but antennomeres 1 and 11; the metaventrite is sparsely granulate; the femora are not ventrally flattened; a fringe of tomentum is present on the protibiae only; and protarsomere 5 is bulbous. Etymology. Finegan , a noun in apposition, from the type locality, Finegan Springs. Habitat. Finegan Springs ( Figs. 1 , 27, 28 ) are located in the Devils River State Natural Area ( Texas Parks and Wildlife Department) west of Loma Alta, Texas , in the Edwards Plateau Ecoregion ( Bureau of Economic Geology 2010 ). At the site, a series of small springs ( Fig. 28 ) emerge from early Cretaceous Edwards Limestone ( Bureau of Economic Geology 1992 ) at the base of a limestone bluff adjacent to the east bank of the upper Devils River, joining to form a stream that flows over impermeable chert bedrock (B. F. Schwartz, in litt.) before emptying into the river ( Fig. 27 ). Historic discharges from the springs ranged between 99– 760 L/s ( Brune 1981 ) from five measurements taken in the years 1928–1971. The single specimen of T. finegan was collected from the spring outlet termed “Finegan Spring 1” in Külköyluoğlü et al. (2011) . Associated Fauna. Finegan Springs are the type locality for the spring-endemic ostracod Bicornucandona fineganensis Külköyluoğlü, Gibson, Diaz, and Colin (2011) . Other subterranean aquatic fauna present in the outflow of the springs includes the isopods (Crustacea) C. texensis , Lirceolus sp. , and S. hardeni and the amphipods (Crustacea) A. subterranea , P. americana, Paraholsingerius smaragdinus (Holsinger), P. ruffoi , S. hershleri , and Stygobromus hadenoecus (Holsinger) . Epigean riffle beetles present in the springs include H. glabra , unidentified Microcylloepus , P. clavicornis (Elmidae) and Psephenus Haldeman (almost certainly P. texanus although adults have not been collected) ( Psephenidae ); the population of H. glabra at the springs was included in a population genetics study of Heterelmis by Gonzales (2008) . An unidentified species of marsh beetle in the genus Prionocyphon Redtenbacher (Scirtidae) has also been identified from the springs. The spring-associated roundnose minnows D. diaboli and D. argentosa regularly occur in the stretch of the Devils River from Finegan Springs to Dolan Falls 1.5 km downstream.