Two new species of blind, forest litter-inhabiting ground beetles from the subtribe Anillina (Carabidae: Trechinae: Bembidiini) from eastern U.S.A.

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1 Zootaxa 1740: (2008) Copyright 2008 Magnolia Press ISSN (print edition) ZOOTAXA ISSN (online edition) Two new species of blind, forest litter-inhabiting ground beetles from the subtribe Anillina (Carabidae: Trechinae: Bembidiini) from eastern U.S.A. IGOR M. SOKOLOV 1 & CHRISTOPHER E. CARLTON 2 Louisiana State Arthropod Museum, Department of Entomology, LSU Agricultural Center Baton Rouge, Louisiana, 70803, USA. E- mail: 1 isokolov@agcenter.lsu.edu; 2 CCarlton@agcenter.lsu.edu Abstract Two new species of anilline ground beetles are described from the Appalachian Mountains of eastern United States. The description of Serranillus septentrionis n. sp. is based on specimens collected in montane areas of western Virginia ( N, W). This species extends the range of the genus approximately 200 km north of its closest known congeners, S. dunavani (Jeannel) and S. jeanneli Barr, and differs from them mainly in characters of the male genitalia. A key is provided that will allow separation of these three species without dissection. The description of Anillinus cherokee n. sp. is based on specimens collected in Great Smoky Mountains National Park and nearby areas of Nantahala National Forest, western North Carolina ( N, W). The species is externally similar to A. loweae Sokolov and Carlton and A. steevesi Barr, and differs from those species in characters of the male genitalia. Key words: Coleoptera, Adephaga, Carabidae, Anillinus, Serranillus, Appalachian Mountains, new species, identification key Introduction Intensive sampling of the litter fauna in the Great Smoky Mountains National Park (GSMNP), and adjacent areas in the eastern United States from 2000 to 2006 has resulted in the discovery of numerous new species of beetles (Gusarov 2002; Konstantinov & Tishechkin 2004; Gimmel & Ślipiński 2007; Tishechkin 2007), mostly from the subtribe Anillina (Sokolov et al. 2004, 2007). In addition to these, two distinctive new species of forest litter anillines belonging to two genera, Serranillus Barr and Anillinus Casey are described herein. Serranillus, until the present paper, has included two species, S. jeanneli Barr and S. dunavani (Jeannel) with ranges occupying southern counties of North Carolina, south-eastern counties of Tennessee and northern counties of Georgia and South Carolina. The discovery of a new species of Serranillus far northwards is a significant range extension of the genus. The new species of Anillinus described herein is unique among the known species of the genus in Southern Appalachians based on the distinctive form of the aedeagal median lobe. In addition to these descriptions, we provide a determination key for all known species of Serranillus. Material and methods Specimens were collected by sifting litter and using Berlese funnels. All specimens were measured electronically using a Leica Z16 APO microscope equipped with a Syncroscopy AutoMontage photomicroscopy system (SYNCROSCOPY, Synoptics Ltd.). Measurements for various body parts are encoded as follows: ABL = Accepted by W. Moore: 18 Feb. 2008; published: 2 Apr

2 apparent body length, from clypeus to apex of elytra; WH = width of head, at level of first orbital setae; WPm = maximal width across pronotum; WPa = width across anterior angles of pronotum; WPp = width across posterior angles of pronotum; LP = length of pronotum from base to apex along midline; WE = width of elytra, at level of 2 nd discal setae; LE = length of the elytra, from apex of scutellum to apex of left elytron. ABL measurements are given in mm; others are presented as seven ratios: mean widths WH/WPm and WPm/WE and body parts WPa/WPp, WPm/WPp, WPm/LP, LE/ABL and WE/ABL. All values are given as mean ± standard deviation. Verbatim label data are given for type specimens of all newly described species, with label breaks indicated by a slash ( / ). Type depositions are indicated under each species treatment. Dissections of genitalia were made using standard techniques as described previously (Sokolov et al. 2004, 2007). Terminology of female genitalia structures follows Maddison (1993): the nodulus is the basal section of the spermatheca, near the attachment of the spermathecal duct; the ramus is the area near the attachment of the spermathecal gland, the cornu is the distal-most portion of the spermatheca adjacent to the ramus. Depending of the presence/absence of a projection around the area of the spermathecal gland attachment, the ramus may be differentiated or undifferentiated. Photographs of the dorsal habitus of new species were taken with the AutoMontage system. Line drawings of selected body parts were made using a camera lucida on an Olympus BX 50 compound microscope. Comparisons of new to described species of Serranillus were based on specimens of S. jeanneli from White County, Georgia and specimens of S. dunavani from GSMNP. For Anillinus species we based comparisons on specimens of A. loweae from GSMNP and A. steevesi from Dade County, Georgia. Taxonomic notes. Investigation of the new species of Serranillus and recently collected specimens of S. jeanneli revealed that microsculpture of the head and pronotum could not be used for separating the genus from Anillinus, as previously indicated (Sokolov et al. 2004). In both genera the condition of microsculpture on the front and vertex of the head should be stated as variable. Serranillus septentrionis Sokolov and Carlton, new species Holotype. Male labeled / VIRGINIA: Botetourt Co., Blue Ridge Pwy., Black Horse Gap, N W, 745m. Litter sifting, 2 May 2006 A.K.Tishechkin / / HOLOTYPE, Serranillus septentrionis Sokolov and Carlton, des. 2007/. Deposited U.S. National Museum (USNM). Type locality. U.S.A, VA, Botetourt Co., Blue Ridge Pwy., Black Horse Gap, N W. Paratypes (6). One male and 1 female with same data as holotype; 1 male labeled / USA VA: Giles Co., Jefferson NF, Flat Top Mt., at N W, forest litter, 1120m, C.E.Carlton 25 May 2006/; 2 males labeled / USA VA: Giles Co., Jefferson NF, Flat Top Mt., at N W, 1080m, forest litter, C.E.Carlton 25 May 2006/; 1 female labeled / USA VA: Giles Co., Jefferson NF, Flat Top Mt., at N W, hardwood berlese, 400m, C.E.Carlton 25 May 2006/. Deposited Louisiana State Arthropod Museum (LSAM). Etymology. The specific epithet "septentrionis" (Latin, the northern regions, the northern countries, the north ) is an adjective referring to the geographic range of the species, the most northern among known species of the genus. Description. Large for genus (ABL range mm, mean 2.07±0.053 mm, n=7). Sexes of approximately equal size: size of males ABL range mm, mean 2.06±0.055 mm, n=5, size of females ABL range mm, mean 2.09±0.064 mm, n=2. Habitus (Fig. 1) markedly convex, ovoid (WE/ABL ), head normally proportioned for genus (WH/WPm ), pronotum narrow compared to elytra (WPm/WE ). Body color dark, from dark brunneous to brunneorufous, appendages much lighter, testaceous. Microsculpture fine but distinct across dorsal surface of pronotum and most of head. On head only the vertex lacks microsculpture. Elytra with well-developed polygonal microsculpture. 38 Zootaxa Magnolia Press SOKOLOV & CARLTON

3 Pronotum moderately convex and comparatively strongly transverse (WPm/LP ), with margins rectilinear and moderately constricted posteriad (WPm/WPp ). Anterior angles evident, slightly prominent. Posterior angles slightly obtuse ( ). Width between posterior angles slightly greater than between anterior angles (WPa/WPp ). Elytra markedly convex, slightly depressed along suture, of normal length for genus (LE/ABL ), with traces of 1 2 interneurs. Humeri moderately prominent, in outline forming an obtuse angle with longitudinal axis of body, dorsally moderately rounded, gradually enlarged to middle. Margins subparallel, slightly divergent in basal half, evenly rounded to apex, maximum width of elytra behind midpoint. Elytra without subapical sinuation. Vestiture of elytra long (about half length of discal setae). Prothoracic leg of males with strongly dilated tarsomere 1 and moderately dilated tarsomere 2. Profemur moderately swollen. Metafemora unmodified. Males with three denticles on the apex of the sternum VII. 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. Median lobe (Fig. 3) nearly straight, with elongate, gradually narrowing and somewhat acute apex, ventral margin with obvious striation and few poriferous canals. Canals absent on walls of median lobe itself. Copulatory sclerites represented by two weakly sclerotized plates, subquadrate in form and one after the other in position. Walls of invagination of apical orifice obviously sclerotized and forming a wavy contour. Left paramere (Fig. 4) with enlarged base, which is distinctly separated by a wide border from the distal part of the paramere; paramere apex without visible setae (at X400). Right paramere absent. NEW SPECIES OF ANILLINA FROM EASTERN U.S.A. Zootaxa Magnolia Press 39

4 Spermatheca (Fig. 5) moderately sclerotized, with three well-developed parts. Distal part, the cornu, is sclerotized and bean-like in form, more than 2 times longer than wide. Proximal part of cornu unsclerotized and straight, with traces of coils. Ramus well-differentiated, sclerotized, ovoid. Nodulus short. Spermathecal duct comparatively short, more or less straight, without obvious coils. Stylomeres and sternum IX as in Figure 6. Sternum with 8 9 setae. Distribution. Known from Giles and Botetourt Counties, Virginia. Habitat. Beetles were collected in litter of deciduous hardwood forest from a wide range of altitudes ( m). Differential diagnosis. Serranillus septentrionis in general outline is very similar to S. jeanneli, but easily distinguished from the latter by the form of the apex of the median lobe. The latter species has comparatively shorter and subparallel apex of median lobe with a rounded tip. In comparison with S. dunavani the new species is noticeably larger and has a comparatively smaller head. Additionally, the range of the new species is far north of the ranges of both previously known species of Serranillus (Fig. 7). Key for identification of Serranillus species This key will allow determination of all known Serranillus species. 1. Smaller, under 1.9mm in length. Head relatively larger relative to pronotum (WH/WPm )... Serranillus dunavani (Jeannel) - Larger, over 2.0mm in length. Head smaller relative to pronotum (WH/WPm ) Median lobe with gradually narrowing apex with the subacute tip. Beetles from the middle Appalachian Mountains (Virginia)... Serranillus septentrionis, new species - Median lobe with subparallel apex with slightly enlarged and rounded tip. Beetles from southern Appalachian Mountains (North Carolina)... Serranillus jeanneli Barr Anillinus cherokee Sokolov and Carlton, new species Holotype. Male labeled / USA-NC: Graham Co., Spirit Ridge, Nantahala NF, Joyce Kilmer Memorial, W, N, leaf/log Berlese C.Carlton 05 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, W, 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 N W. elev. 630m. Leaf litter sifting 28 July 2004 A. Tishechkin /; 1 male labeled / TENNESSEE: Blount Co., GSMNP, upper Gregory Ridge Tr. at N 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 05 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 mm, mean 1.79±0.090 mm, n=16). Males noticeably larger than females: male size ABL range mm, mean 1.83±0.066 mm, n=11, female size ABL range mm, 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. 40 Zootaxa Magnolia Press SOKOLOV & CARLTON

5 Microsculpture distinct across dorsal surface pronotum and head except for two paramedian patches on vertex without microsculpture. Elytra with well-developed polygonal microsculpture. FIGURES 3 6. Serranillus septentrionis, new species, (VA, Giles Co., Jefferson National Forest). Male aedeagus : 3 median lobe, 4 left paramere; female genitalia: 5 spermatheca, 6 right stylomere and sternum IX. Scale=100µm. 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 ( ). 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). NEW SPECIES OF ANILLINA FROM EASTERN U.S.A. Zootaxa Magnolia Press 41

6 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 ( m). 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). 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. 42 Zootaxa Magnolia Press SOKOLOV & CARLTON

7 FIGURES 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=100m. NEW SPECIES OF ANILLINA FROM EASTERN U.S.A. Zootaxa Magnolia Press 43

8 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. Acknowledgements We would like to thank Alexey Tishechkin (Louisiana State Arthropod Museum, LSU AgCenter, Baton Rouge) for his efforts in collecting these and other new species of anillines. This manuscript is published with the approval of the Director of the Louisiana Agricultural Experiment Station as manuscript number Support was provided by grants from Discover Life in America and the National Science Foundation (DEB , C. E. Carlton and V. L. Bayless, Co-P.I.s). References Barr, T.C. (1995) Notes on some anillines (Coleoptera, Carabidae, Bembidiinae) from southeastern United States, with description of a new genus and two new species. Special Bulletin Japanese Society of Coleopterology, Tokyo, 4, Gimmel, M.L. & Ślipinski, S.A. (2007) A new species of the genus Philothermus Aubé (Coleoptera: Cerylonidae) from Great Smoky Mountains National Park, U.S.A. Zootaxa, 1390, Gusarov, V.I. (2002) A revision of Nearctic species of the genus Geostiba Thomson, 1858 (Coleoptera: Staphylinidae: Aleocharinae). Zootaxa, 81, Konstantinov, A. & Tishechkin, A. (2004) The first Nearctic leaf litter flea beetle (Coleoptera: Chrysomelidae) from the Great Smoky Mountains National Park. Coleopterists Bulletin, 58(1), Maddison, D.R. (1993) Systematics of the holarctic beetle subgenus Bracteon and related Bembidion (Coleoptera: Carabidae). Bulletin of the Museum of Comparative Zoology, 153, Sokolov, I.M., Carlton, C.E., & Cornell, J.F. (2004) Review of Anillinus, with descriptions of 17 new species and a key to soil and litter species (Coleoptera: Carabidae: Trechinae: Bembidiini). Coleopterists Bulletin, 58, Sokolov, I.M., Sokolova, Y.Y. & Carlton, C.E. (2007) New species of Anillinus Casey (Carabidae: Trechinae: Bembidiini) from Great Smoky Mountains National Park, U.S.A. and phylogeography of the A. langdoni species group. Zootaxa, 1542, Tishechkin, A.K. (2007) A new species of Ptomophagus (Appadelopsis) (Coleoptera: Leiodidae) from Great Smoky Mountains National Park, U.S.A. Zootaxa, 1478, Zootaxa Magnolia Press SOKOLOV & CARLTON