Anillinus cherokee Sokolov and Carlton

Sokolov, Igor M. & Carlton, Christopher E., 2008, Two new species of blind, forest litter-inhabiting ground beetles from the subtribe Anillina (Carabidae: Trechinae: Bembidiini) from eastern U. S. A., Zootaxa 1740, pp. 37-44 : 40-44

Anillinus cherokee Sokolov and Carlton , new species

Holotype. Male labeled / USA-NC: Graham Co., Spirit Ridge, Nantahala NF, Joyce Kilmer Memorial, 83°56’03”W, 35°21’20”N, leaf/log Berlese C.Carlton 0 5 Apr 2004 / / HOLOTYPE, Anillinus cherokee Sokolov and Carlton , des. 2007/. Deposited U.S. National Museum ( USNM).

Type locality. U.S.A., NC, Graham Co., Nantahala National Forest, Spirit Ridge, Joyce Kilmer Memorial, 83°56’03”W, 35°21’20”N.

Paratypes (15). Six males and 5 females with same data as holotype; 1 male labeled / TENNESSEE: Blount Co., GSMNP, lower Gregory Ridge Tr. at 35°33.5’ N 83°50.5’W. elev. 630m. Leaf litter sifting 28 July 2004 A. Tishechkin /; 1 male labeled / TENNESSEE: Blount Co., GSMNP, upper Gregory Ridge Tr. at 35°31.61’ N 83°51.18’W, 1315m. Forest litter sifting. 12 Apr 2006 A.K. Tishechkin /; 2 males labeled / USA- NC: Graham Co., Spirit Ridge, Cherohala Scenic Skyway, elv.4950’, leaf/log litter Berlese C.Carlton 0 5 Apr 2004 /. Deposited Louisiana State Arthropod Museum ( LSAM).

Etymology. The specific epithet is a noun in apposition referring to the Cherokee Tribe of native Americans. The East Band of the Cherokees was indigenous to the region where the species occurs.

Description. Medium-sized for genus (ABL range 1.62–1.92mm, mean 1.79± 0.090 mm, n=16). Males noticeably larger than females: male size ABL range 1.73–1.92mm, mean 1.83± 0.066 mm, n=11, female size ― ABL range 1.62–1.76mm, mean 1.69± 0.060 mm, n=5. Habitus ( Fig. 2 ) markedly convex, ovoid (WE/ABL 0.39±0.008), head normally proportioned for genus (WH/WPm 0.73±0.020), pronotum narrow compared to elytra (WPm/WE 0.78±0.012). Body color brunneous to brunneorufous, appendages much lighter, testaceous.

Microsculpture distinct across dorsal surface pronotum and head except for two paramedian patches on vertex without microsculpture. Elytra with well-developed polygonal microsculpture.

Pronotum moderately convex and transverse (WPm/LP 1.23±0.019), with margins rectilinear and moderately constricted posteriad (WPm/WPp 1.25±0.015). Anterior angles evident, slightly prominent. Posterior angles slightly obtuse (105–110°). Width between posterior angles greater than between anterior angles (WPa/ WPp 0.93±0.029).

Elytra moderately convex, slightly depressed along suture, of normal length for genus (LE/ABL 0.57±0.016), with traces of 1–2 interneurs. Humeri slightly prominent, oblique, in outline forming an obtuse angle with longitudinal axis of body, gradually enlarged to middle. Margins subparallel, slightly divergent in basal half, evenly rounded to apex, maximal width of elytra behind midpoint. Elytra without subapical sinuation. Vestiture of elytra short (less than one-third length of discal setae).

Prothoracic leg of males with moderately dilated tarsomere 1 and 2 and moderately swollen profemur. Metafemora unmodified.

Median lobe ( Fig. 8 ) evenly arcuate and twisted, with somewhat enlarged, rounded apex, upper margin of which is slightly raised. Ventral margin of median lobe weakly enlarged and with numerous poriferous canals. Canals also present on walls of median lobe itself. Dorsal copulatory sclerites semicircular, formed by two plates and combined together in one curved contour with wavy sides. Each end of both sclerites joined together and elongated to form a short filament. Ventral sclerite and spines of internal sac absent.

Right paramere ( Fig. 9 ) slightly enlarged with four short setae, two proximal setae greatly reduced in length. Left paramere ( Fig. 10 ) elongated, subparallel, with four equal setae shifted towards the lower margin.

Spermatheca ( Fig. 11 ) moderately sclerotized, shaped like a question mark, represented mostly by long and well-developed cornu with apical one-half sinuate. Distal part of cornu comparatively short, about 1.5 times longer than its width. Curvature of distal part much wider than those of its proximal part adjacent to ramus. Ramus undifferentiated, nodulus short. Spermathecal duct more or less straight, without obvious coils.

Stylomeres and sternum IX as in Figure 12 . Sternum with 7–8 setae.

Distribution. Known from southeastern parts of Blount County, Tennessee, within Great Smoky Mountains National Park and adjacent parts of Nantahala National Forest, Graham County, North Carolina.

Habitat. Beetles were collected in litter of deciduous hardwood forests at middle altitudes (600–1510m). Despite the wide range of altitudes represented, the species predominantly occupies the upper forest zone (> 1000m), where it is comparatively common (e. g., Cherohala Skyway Drive, extreme western North Carolina).

Differential diagnosis. Anillinus cherokee is a member of a group of ovoid species with partially microsculptured head (two paramedian spots on vertex are lacking microsculpture). The representatives of three other species with partially microsculptured head potentially can be found sympatrically with the new species. Among them, externally only Anillinus murrayae Sokolov and Carlton can be distinguished from the new species by the absence of microsculpture on the pronotum. Two other species, A. loweae Sokolov and Carlton and A. steevesi Barr , externally are practically indistinguishable from the new species, though examination of the genitalia will separate them. Males of A. steevesi can be separated from A. cherokee by the presence of a group of setae on the ventral margin of the median lobe and by the length of the dorsal sclerites, which extend beyond the median lobe. Males of A. loweae can be separated from the A. cherokee by the presence of a cluster of spines near the apical orifice in the inner sac of the median lobe and by the dentate contour of the apex of median lobe. Females of both species can be separated from the A. cherokee by the general form of their spermathecae. The proximal part of the cornu in these species has approximately the same width and curvature as the distal part, so the spermathecae of A. steevesi and A. loweae have a more S-shape than the question mark shape characteristic for the spermatheca of A. cherokee .

Biogeographical notes. Discovery of the new species of Serranillus is a significant northern range extension of the genus ( Fig. 7 ). Also, the distributions of Serranillus and Anillinus in the Appalachian Mountains now became similar in general outline. Probably, this similarity, in combination with the different structures of the aedeagi of the two genera reflects a similar and parallel biogeographic and phylogenetic history.

Figures

FIGURE 7. Schematic distribution of the Serranillus species. 1 – S. jeanneli Barr; 2 – S. dunavani (Jeannel); 3 – S. septentrionis, new species. From Barr (1995) and original data.

FIGURES 1 – 2. Habitus of (1) Serranillus septentrionis, new species (VA, Botetourt Co., Black Horse Gap), and (2) Anillinus cherokee, new species (TN, Blount Co., Great Smoky Mountains National Park), dorsal aspect, males.

FIGURES 8 – 12. Anillinus cherokee, new species, (NC, Graham Co., Nantahala National Forest). Male aedeagus: 8 – median lobe, 9 – left paramere, 10 – right paramere; female genitalia: 11 – spermatheca, 12 – right stylomere and sternum IX. Scale = 100 m.