Zootaxa, Two New Species of Blind, Forest Litter-Inhabiting Ground
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TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. Zootaxa 1740: 37–44 (2008) ISSN 1175-5326 (print edition) www.mapress.com/zootaxa/ ZOOTAXA Copyright © 2008 · Magnolia Press ISSN 1175-5334 (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. SOKOLOV1 & CHRISTOPHER E. CARLTON2 Louisiana State Arthropod Museum, Department of Entomology, LSU Agricultural Center Baton Rouge, Louisiana, 70803, USA. E- mail: [email protected]; [email protected] 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 (37°25.33’N, 79°45.43’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 (35°21.33’N, 83°56.05’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, identifica- tion 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 spe- cies 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 (Jean- nel) 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 north- wards 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 Serra- nillus. Material and methods Specimens were collected by sifting litter and using Berlese funnels. All specimens were measured electroni- cally using a Leica Z16 APO microscope equipped with a Syncroscopy AutoMontage photomicroscopy sys- tem (SYNCROSCOPY, Synoptics Ltd.). Measurements for various body parts are encoded as follows: ABL = Accepted by W. Moore: 18 Feb. 2008; published: 2 Apr. 2008 37 TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. 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 pos- terior angles of pronotum; LP = length of pronotum from base to apex along midline; WE = width of elytra, at level of 2nd discal setae; LE = length of the elytra, from apex of scutellum to apex of left elytron. ABL mea- surements 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 ± stan- dard 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 attach- ment 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 draw- ings 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 compari- sons 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, 37°25.33’ N 79°45.43’ 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, 37°25.33’ N 79°45.43’ 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 37°14.6’ N 80°52.0’ W, forest litter, 1120m, C.E.Carlton 25 May 2006/; 2 males labeled / USA–VA: Giles Co., Jefferson NF, Flat Top Mt., at 37°14.0’ N 80°52.5’ W, 1080m, forest litter, C.E.Carlton 25 May 2006/; 1 female labeled / USA–VA: Giles Co., Jefferson NF, Flat Top Mt., at 37°13.8’ N 80°52.4’ 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 spe- cies of the genus. Description. Large for genus (ABL range 2.00–2.14mm, mean 2.07±0.053 mm, n=7). Sexes of approxi- mately equal size: size of males ABL range 2.00–2.14mm, mean 2.06±0.055 mm, n=5, size of females ABL range 2.04–2.13mm, mean 2.09±0.064 mm, n=2. Habitus (Fig. 1) markedly convex, ovoid (WE/ABL 0.39+0.010), head normally proportioned for genus (WH/WPm 0.72+0.017), pronotum narrow compared to elytra (WPm/WE 0.79+0.011). 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 1740 © 2008 Magnolia Press SOKOLOV & CARLTON TERM OF USE This pdf is provided by Magnolia Press for private/research use. Commercial sale or deposition in a public library or website site is prohibited. Pronotum moderately convex and comparatively strongly transverse (WPm/LP 1.33+0.043), with margins rectilinear and moderately constricted posteriad (WPm/WPp 1.31+0.032). Anterior angles evident, slightly prominent. Posterior angles slightly obtuse (105–110°). Width between posterior angles slightly greater than between anterior angles (WPa/WPp 0.97+0.027). Elytra markedly convex, slightly depressed along suture, of normal length for genus (LE/ABL 0.58+0.015), 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 subparal- lel, 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. Copula- tory 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 1740 © 2008 Magnolia Press · 39 TERM OF USE This pdf is provided by Magnolia Press for private/research use.