Arianops hiltenae, Carlton, 2008

Carlton, Christopher E., 2008, Eight New Species ofArianopsBrendel from the Southeastern United States with an Updated Key and Notes on Additional Species (Coleoptera: Staphylinidae: Pselaphinae), The Coleopterists Bulletin 62 (2), pp. 297-323 : 297-323

Arianops hiltenae , new species

( Figs. 15–16 , 32–33 , 40 )

Holotype male ( Figs. 15–16 ). /TN: Blount Co., GSMNP, White Oak Sink , 35 ° 38 9 07 0 N 83 ° 44 9 49 0, 620 m, mixed forest, litter hand sifting, Sokolov, I.M. 16.06.2006 / Arianops hiltenae Carlton, 2007 Holotype male/. Type deposition, Field Museum of Natural History, Chicago, IL .

Etymology. This species is named after Jeanie Hilten, Director Emeritus of Discover Life in America, Inc., supporter, and promoter of the All Taxa Biodiversity Inventory in Great Smoky Mountains National Park.

Description. Holotype male. Measurements (in mm): head 0.50 long, 0.50 wide; pronotum 0.45 long, 0.55 wide; elytra 0.60 long, 0.70 wide; median lengths of visible abdominal tergites 1–5, respectively 0.35, 0.10, 0.08, 0.30, 0.08. Antennomeres 1–11, respectively 0.11, 0.10, 0.10, 0.10, 0.08, 0.08, 0.08, 0.06, 0.07, 0.06, 0.22. Aedeagus 0.30 long, 0.25 wide. Total length 2.30.

Head ( Fig. 32 ). Lateral vertexal carinae weak, discernable above antennal tubercles, becoming obsolete at a point well before vertexal foveae. Traces of median occipital carina visible, discontinuous between base of occiput and vertex. Vertexal foveae small, shallow, not connected via circumambient sulcus, vertex evenly convex, almost flat between antennal tubercles. Carinae to antennal tubercles not extending onto clypeus; clypeus not carinate medially. Labral margin bearing four minute denticles. Lateral carinae from clypeus to ocular spines well-developed. Ocular spine moderate, triangularly acute, oriented laterally. Mentum not toothed.

Pronotum. Basomedian fovea absent, submedian spines and bumps absent. Basolateral foveoid depression barely discernable at certain angles of lighting. Pronotum weakly transversely rugose along basolateral margin, smooth medially.

Elytra. Basal margin of each elytron straight to humeral declivity. Basal depressions and foveae absent.

Legs unmodified.

36) A. ashei ; 37) A. barri ; 38) A. folkertsi ; 39) A. gorei ; 40) A. hiltenae .

Abdomen. Dorsally weakly rounded, evenly, gently declivous at tergite 4. Visible ventrite 3 with a short, broad, median, marginal shelf ( Fig. 33 ). Ventrite 6 broadly concave.

Aedeagus ( Fig. 40 ). Parameres absent. Ventral shelf acutely pointed left due to prolongation of right margin and emargination of left, giving aedeagus the overall shape of a comma. Right base of shelf bearing a loose group of five setae, apex with two setae. Short triangular process from left interior of phallobase bearing three terminal setae.

Female. Unknown.

Material examined. Only the holotype is known.

Distribution. The species is only known from the type locality in Blount County, Tennessee.

Comments. External characters of A. hiltenae are consistent with Barr’s (1974) cavernensis species group. The species is similar to A. cavernensis Park (1951) in that 318 the median vertexal carina is almost completely absent, and the pronotal foveae, tubercles and spines are absent. These are the only two species having this degree of reduction of these features. The lateral vertexal carinae of A. hiltenae are weakly developed whereas they are absent on A. cavernensis . The vertexal foveae of A. hiltenae are small, but obvious, whereas those of A. cavernensis are vestigial and reduced to small pits. Unfortunately, A. cavernensis is based only on the female holotype, so an aedeagal comparison is not possible, and these comparisons are based on Barr’s (1974) description. The differences in the lateral vertexal carinae and vertexal foveae, and the widely separated localities (, 250 km) support placement as a distinct species.

White Oak Sink, near the northwest boundary of Great Smoky Mountains National Park, is part of a small area within the park having a karst substrate with a network of interconnected limestone caves. While a number of Arianops species have been collected in caves and may be obligate troglobites, especially within the cavernensis species group, the holotype of A. hiltenae was collected sifting forest litter, 10 m from the nearest cave opening (I. Sokolov, pers. comm.). Litter collections from small caves and sinkholes in the immediate vicinity have thus far failed to produce additional specimens. Barr (1974) discussed habitats where other members of the species group have been taken. Most seem to be edaphobites of deep litter in karst landscapes, and their association with caves may be incidental. The troglophilic carabid Trechus tuckaleechee Barr , originally described from Tuckaleechee Cave, a short distance outside the park, has also been collected at this locality.

NOTES ON PREVIOUSLY DESCRIBED SPECIES

Figures

Figs. 13–16. Dorsal and lateral views, Arianops new species holotypes. 13–14) A. gorei;

Figs. 28–33. Arianops new species. 28) A. folkertsi, head; 29) A. folkertsi, ventrites 3–4; 30) A. gorei, head; 31) A. gorei, ventrites 3–4; 32) A. hiltenae, head; 33) A. hiltenae, ventrites 3–4.

Figs. 34–41. Arianops new species aedeagi, dorsal views. 34) A. carteri; 35) A. clintoni;