Anillinus forthoodensis Sokolov & Reddell

Sokolov, Igor M., Reddell, James R. & Kavanaugh, David H., 2014, Life beneath the surface of the central Texan Balcones Escarpment: genus Anillinus Casey, 1918 (Coleoptera, Carabidae, Bembidiini): new species, a key to the Texas species, and notes about their way of life and evolution, ZooKeys 417, pp. 71-101 : 84-87

Taxon classification Animalia Coleoptera Carabidae

Anillinus forthoodensis Sokolov & Reddell sp. n. Figs 2B, E, H–I, 3A, C, 4 A–C, F, 5F, 6 N–P, 7A, E, 8

Type material.

HOLOTYPE, a male, deposited in CAS, point-mounted, dissected, labeled: \ TX: Bell Co., Talking Crows Cave, Fort Hood, 4.V.2006, J. Fant, M. Reyes \ Texas Memorial Museum Invertebrate Zool Coll #45.781 \ Holotype Anillinus forthoodensis Sokolov & Reddell 2014 [red label] \ CAS Type No. 18872. PARATYPES: 4 males and 3 females; two males and one female, in TMM, labeled same as holotype; one male, in CNC, labeled: \ TX: Bell Co., Talking Crows Cave, Fort Hood, 2 June 2005, J. Fant, J. Reddell, M. Reyes \ Texas Memorial Museum Invertebrate Zool Coll #38.153 \; one female, in TMM, labeled: \ TX: Bell Co., Nolan Creek Cave, Fort Hood, 27.IV.2007, J. Fant, J. Reddell \ Texas Memorial Museum Invertebrate Zool Coll #55.333 \; one male and one female, in TMM, labeled: \ TX: Bell Co., Bell Cave, Fort Hood, 4 March 2010, J. Fant \ Texas Memorial Museum Invertebrate Zool Coll #70.872 \. All paratypes also labeled: \ Paratype Anillinus forthoodensis Sokolov & Reddell 2014 [yellow label] \.

Type locality.

U.S.A., Texas, Bell County, Fort Hood area.

Etymology.

The specific epithet is a Latinized adjective in the masculine form based on Fort Hood, the U. S. military post located in Texas, from the surroundings of which the new species is described.

Recognition.

Adults of this new species are distinguished easily from those of other Texan species of the genus by the following combination of external characters: small size, markedly elongate habitus, distinctly elongate pronotum with shallowly sinuate lateral margins, and truncate apex of elytron.

Description.

Medium-sized for genus (SBL range 1.65-1.73 mm, mean 1.69 ± 0.040 mm, n=4).

Habitus. Body form (Fig. 5F) subdepressed, subparallel, markedly elongate (WE/SBL 0.33 ± 0.010), head large for genus compared to pronotum (WH/WPm 0.79 ± 0.022), pronotum wide in comparison to elytra (WPm/WE 0.88 ± 0.031).

Color. Body rufotestaceous, appendages testaceous.

Microsculpture. Distinct over all dorsal surfaces of head, pronotum and elytra, with slightly transverse polygonal mesh of more or less scaly appearance on elytra.

Head. Labium (Fig. 3A) with mental tooth; mentum and submentum separated by suture. Glossal sclerite with distinct paraglossae laterally and with two setae apically.

Prothorax. Pronotum (Fig. 2E) relatively long (LP/LE 0.43 ± 0.027) and markedly elongate (WPm/LP 1.21 ± 0.024), with lateral margins shallowly sinuate and moderately constricted posteriorly (WPm/WPp 1.29 ± 0.016). Anterior angles indistinct, posterior angles nearly rectangular (90-100°). Width between anterior and posterior angles of approximately equal length (WPa/WPp 1.03 ± 0.012). Basal margin slightly convex.

Elytra (Fig. 2 H–I). Widely depressed along suture, of normal length (LE/SBL 0.56 ± 0.010) and narrow for genus (WE/LE 0.59 ± 0.022), with traces of 4-5 striae. Humeri distinct, rounded, in outline forming obtuse angle with longitudinal axis of body. Lateral margins subparallel, slightly divergent at basal fifth, evenly rounded to apex in apical fourth, without subapical sinuation. Vestiture of elytra short (less than one-third length of discal setae). Apex of elytron truncate (Fig. 2H, 6 specimens out of 7 investigated) or shallowly emarginate (Fig. 2I, 1 female from 7 investigated).

Legs. Male protarsomere 1 markedly dilated apico-laterally with two rows of adhesive setae ventrally (Fig. 4A). Male hind legs modified: trochanters with many minute bumps scattered across ventral surface (Fig. 4B), metafemora triangularly dilated along posteroventral margin with a small tooth at tip of dilation (Fig. 4B, F), and metatibiae with granulate posterior margin (Fig. 4C).

Abdomen. Ventrite 5 of male with medial depression (Fig. 3C).

Male genitalia. Median lobe of aedeagus (Fig. 6N) with short basal lobe, long rectangularly bent shaft, and enlarged apex, broadly rounded at tip. Dorsal margin strongly sclerotized along almost all its length. Ventral margin enlarged along entire length to basal orifice, with numerous poriferous canals. Dorsal sclerite in form of a semicircular blade-like structure with characteristic basal prolongations. Without distinct ventral sclerites. Dorsal membranous field with numerous small spines lo cated dorsally from dorsal sclerite. Enlarged apical area of median lobe with a dark spine-like structure. Right paramere enlarged, long and wide with numerous (>8) long setae (Fig. 6P), with length approximately two-thirds of length of the paramere. Left paramere wide, slightly enlarged apically and basally (Fig. 6O), without long setae.

Female genitalia. Gonocoxite 2 (Fig. 7A) unguiform (gc2), rather long, with slightly curved blade (bl) and narrowly rounded apex, with nematiform (ns) and two ensiform setae, with the lateral (les) of these thicker than the medial (mes). Laterotergite (lt) with 9-10 setae. Spermatheca with distal part of cornu markedly dilated. Nodulus short, ramus undifferentiated (Fig. 7E).

Geographical distribution.

This species is known only from several caves distributed in the Fort Hood area, Bell County, Texas (Fig. 8, white quadrangle), Lampasas Cut Plain.

Way of life.

This species has been found only in caves. Specimens were taken in darkness on the underside of rocks shallowly embedded in soil.

Relationships.

The medially depressed abdominal ventrite 5, the enlargement of the ventral margin of the median lobe and the presence of small spines on the dorsal membranous field in the internal sac of both Anillinus forthoodensis and Anillinus affabilis males suggest that they are the closest relatives among the Texan anillines.