Brachygluta (Brachygluta) arguta ( Casey, 1897 )

Chandler, Donald S., Sabella, Giorgio & Bückle, Christoph, 2015, A revision of the Nearctic species of Brachygluta Thomson, 1859 (Coleoptera: Staphylinidae: Pselaphinae), Zootaxa 3928 (1), pp. 1-91 : 55-56

18. Brachygluta (Brachygluta) arguta ( Casey, 1897)

( Figs 23 , 41 A)

Bryaxis arguta Casey, 1897: 585 . Type localities: Michigan, and Westmoreland County, Pennsylvania. Type depository: USNM, male lectotype designated below.

Brachygluta arguta: Raffray 1904: 225 ; 1908: 231; 1911: 94. Leng 1920: 130. Bowman 1934: 83 (Group I, key), 85. Davies 1991: 128. Downie & Arnett 1996: 581. Poole & Gentili 1996: 380. Chandler 1997: 54. Bousquet et al. 2013 (checklist for Canada).

Material examined, 247 specimens. CANADA: Ontario: Essex Co.: Tilbury, III-24-1967 ( FMNH, 40), IV-2- 1967 ( FMNH, 7), IV-15-1967 ( FMNH, 12), IV-21-1965 ( FMNH, 1), IV-28-1967 ( FMNH, 1), V-2-1961 ( FMNH, 1), VI-29-1967 ( FMNH, 6), VII-1962 ( MHNG, 5), IX-5-1967 ( FMNH, 12), K. Stephan, sifting. Wheatley, IV-8- 1967 ( FMNH, 3), IV-17-1967 ( FMNH, 2), IV-29-1967 ( FMNH, 1), V-3-1967 ( FMNH, 2), VI-10-1967 ( FMNH, 4), K. Stephan, sifting. Kent Co.: Merlin, IV-30-1967, K. Stephan, sifting ( FMNH, 4). Rondeau Prov. Pk., Beach near entrance, VI-3-1985, A. Davies & J.M. Campbell, in debris on beach at high water line ( CNCI, 22). Rondeau Provincial Park, South Beach, VI-5-1985, A. Davies & J.M. Campbell, in debris on beach at high water line ( CNCI, 2). Only province on label: “Ontario” ( MHNG, 1M). Only country on label: “Can.” ( CMNH, 1). USA: District of Columbia: “D.C.” ( CMNH, 2). Illinois: Champaign Co.: University Woods, Urbana, IV-10-1937, M. Farrar ( FMNH, 2); X-16-1933, M. D. Farrar, from soil cover in woods ( INHS, 2); X-3-1933, M. D. Farrar, ground cover ( INHS, 2). Cook Co.: Bowmanville, X-14-1910, Liljeblad ( ANSP, 1); X-16-1904 ( FMNH, 19). Lions Woods, V-5-1984, L.E. Watrous, oak litter ( FMNH, 8). McLean Co.: Funks Grove, IV-27-1981, R.W. Lundgren, at carcass in woods ( RWLC, 1; DSCC, 1); IV-4-1981, R.W. Lundgren, under bark of log ( RWLC, 1). Only state on label: “Ill.” ( CMNH, 1). Indiana: Floyd Co.: New Albany, VII-31-1966, C.E. White, blacklight trap ( FSCA, 1). Monroe Co.: Bloomington, VIII-20-1985 ( FSCA, 1), IX-10-1987 ( FSCA, 1), V-31 / VI-1-1986 ( FSCA, 1), F.N. Young, blacklight trap. Parke Co.: 3 mi SE Montezuma, VIII-3 /4-1992, S. Turner, UV light trap ( EIUC, 1). Wells Co.: I-9-1973, N.M. Downie, tree duff ( FMNH, 1). Maryland: Montgomery Co.: Plummers Island, VI-8/13, W.L. McAtee ( USNM, 1). Michigan: Wayne Co.: Detroit, Hubbard & Schwarz ( USNM, 4; ANSP, 1; MCZC, 1); X, Hubbard & Schwarz ( USNM, 2). New York: Queens Co.: Rock(away) Beach, L.(ong) I.(sland), VI-16-1922 ( USNM, 1). North Carolina: Northampton Co.: 7 km S Jackson, V-21 / VII-1-1987, H Goulet, FIT Camasia slope ( DSCC, 3; CNCI, 1). Ohio: Crawford Co.: Plankton, XI-12-1918, P.S. Bartholomew ( CASC, 3). Cuyahoga Co.: Rocky River Reservation, Cleveland, IX-16-2005, H.J. Lee, vernal pool vacuum sedge clumps ( DSCC, 6); VIII- 31-2005, H.J. Lee, sedge clumps vernal pool area ( DSCC, 14). Delaware Co.: 5 mi N Delaware: V-21-1977, L.E. Watrous, sift debris along lake shore ( DSCC, 2). Fairfield Co.: 11 mi S Lancaster, V-8-1976, Q.D. Wheeler ( DSCC, 1). Franklin Co.: 1 mi N Worthington, III-25-1977, L.E. Watrous, berlese litter near stream ( DSCC, 1). Columbus, XI-20-1976, L.E. Watrous, sift leaf litter ( DSCC, 1); III-9-1980, L.E. Watrous, damp leaf litter ( FMNH, 1). Scioto River, IV-13-1975, L.E. Watrous ( DSCC, 1). Sharon Woods Metropolitan Park, VII-2/10 -1973, A.J. Penniman, pitfall trap ( DSCC, 1). West Campus pond, O.S.U., Columbus, IV-20-1976, D.S. Chandler ( DSCC, 1). Greene Co.: John Bryan State Park, VI-1-1975, D.S. Chandler, sifting river drift ( DSCC, 2). Hocking Co.: 2 mi S Gibisonville, VII-8-1978, L.E. Watrous, sift litter in swamp ( DSCC, 1). Rockbridge, IX-21-1975, D.S. Chandler, sifting forest litter ( DSCC, 1). Lawrence Co.: Ald. Twp., Wayne National Forest, Sharp's Creek, V-23 / VI-7-1995, P. Kovarik, F.I.T. ( LSAM, 2). Pickaway Co.: Circleville, Scioto River at Bridge Crossing Rt. 22, 39o 36.30, VIII-24- 2008, K.D. Karns, flooding gravel along river bank ( KDKC, 1). Portage Co.: Eagle Lake Bog, Nelson Twp., IX- 11-2004, H.J. & C.J. Lee, berl. Sphagnum moss ( DSCC, 1). Pennsylvania: Jefferson Co.: Cook State Forest, 1.2 mi N Cooksburg, Troutman Run, VI-6-1997, D.S. Chandler, leaf litter along stream ( DSCC, 1). Westmoreland Co.: Beatty, IX-11-1896 ( FMNH, 2); St. Vincent, IV-26 ( MCZC, 1). Only state on label: “Pen.” ( CMNH, 3; MNHN, 2). West Virginia: Cabell Co.: Wolfpen Hollow, 3 mi S Culloden, V-15-1998, S.M. & A.T. Clark ( WVDA, 1). Grant Co.: Miser, V-25-1994, S.M. Clark ( WVDA, 1). Kanawha Co.: Guthrie, VII-14-1986, M.C. Thomas, UV trap ( DSCC, 2); V-29-1987, M.C. Thomas, UV trap ( DSCC, 1; WVDA, 6). Mason Co.: McClintic Wildlife station, VII- 26-1986, M.C. Thomas, UV trap ( WVDA, 1; DSCC, 2). Morgan Co.: Widmeyer Wildlife Management Area, VIII- 21-1997, S.M. Clark ( DSCC, 1). Tucker Co.: Dolly Sods Scenic Area, IX-16-1992, S.M. Clark ( DSCC, 1).

Description. BODY: Length 1.84–2.04 mm; usually brown, a few specimens with elytra lighter, or hind body orange-brown; setae on head and pronotum short, curved and suberect, longer and decumbent over rest of body. Head: surface smooth, shining, punctures indistinct. Antennomeres III–VI longer than wide, VII barely longer than wide (as long as wide in female), VIII–X distinctly transverse, VIII about two-thirds width of IX ( Fig. 23 C). Setose area of median vertexal fovea slightly smaller than those of lateral foveae. Pronotum: surface smooth, shining, punctures indistinct. Setose area of median antebasal fovea slightly narrower than those of lateral antebasal foveae. Elytra: surface varying from smooth with indistinct punctures to microreticulate and with distinct punctures, discal stria extending to about four-fifths of elytral length. Abdomen: disc of tergite 1 smooth and shining, lightly punctate. Basal striae of tergite 1 long, divergent, one-half length of paratergite or more in male, one-third to one half paratergite length in female, separated at base by about two-fifths tergite width; with sparse but distinct setose comb at base between striae in males, fringe less distinct in females.

MALE: Metaventrite with transverse band of long dense setae between metacoxae. Only tergites 1–2 visible in dorsal view, tergite 1 twice as long as 2; tergite 1 with disc smoothly and shallowly convex, apex shallowly emarginate at middle, with row of appressed golden setae forming elongate flattened lamina, lamina shallowly emarginate at apex and directly posteroventrally ( Fig. 23 A); tergite 2 with semicircular impression at middle extending from base to or near to apex, narrow median strip glabrous, lateral portions of impression with setae suberect, directed obliquely medially, denser and more elongate than on lateral portions of tergite; lateral portions of tergite 2 with flattened or lightly impressed area, setae in this area much shorter and appressed; tergites 3–5 evenly convex, not modified ( Fig. 23 B); in lateral view with tergite 1 rising toward deflexed apex, 2 clearly lower, sloping ventrally from base of 1. Ventrites broadly rounded. Metatibiae thin, narrow at base, gradually widened to near apex, mesal margin of apical fifth with brush present ( Fig. 23 D). Aedeagus 0.37 mm long; with parameres curved laterally in apical portion, lacking distinct preapical constriction, with three aciculate preapical setae on lateral margin, with broad, flat, hyaline seta on inner margin near apex; dorsal plate asymmetric, abruptly narrowed near base, thin to apex, apical portion with margins about same width until curving slightly to right at apex or nearly straight ( Fig. 23 I); internal sac with two large isolated spines and complex thick tooth with cluster of 3-6 small spines on apical portion ( Figs 23 E–H).

FEMALE: Metaventrite with setae in middle portion denser than laterally; abdominal tergites evenly convex; ventrites broadly convex. Metatibiae similar to those of male.

Collecting data. Harry J. Lee has collected many specimens from sedge clumps in and around vernal pools in the Cleveland area of Ohio. Specimens have also been taken from river drift, and from litter on pond and lake shores, as well as being collected by ultraviolet lights ( Chandler 1997). This species appears to prefer leaf litter in and around forested freshwater swamps, as well as litter along the margins of streams. Collected from March to October, with one record from January.

Distribution ( Fig. 41 A). This is a species of the mid-western and the western portion of the northeastern United States that has also been commonly taken from southern Ontario in Canada. There is only one record from east of this area, with a single specimen being taken from Long Island (New York).

Comments. This species is similar in appearance to B. wickhami , in being small and dark, and the male modifications of tergite 2 are similar in general form. Brachygluta arguta has the slightly asymmetrical median lobe of the aedeagus long and thin, a thick spine in the internal sac with 3–6 (usually 4) small spines at the apex, and the impression of tergite 2 has the apex semicircular with the lateral portions of the impression not densely setose. Brachygluta wickhami has the symmetrical median lobe of the aedeagus shorter and broadly triangular, and the more longitudinal impression of tergite 2 extends to or close to the tergite apex, with the lateral portions of the impression being densely setose and a median longitudinal glabrous strip present through most of the length of the impression. Both B. arguta and B. wickhami have the setose portion of the median pronotal fovea narrower than for the lateral foveae, while in B. terebrata the setose portion of all pronotal foveae are similar in size.

Lectotype is here designated, and Paralectotypes recognized and labeled as such. Lectotype male: // Mich/ Casey bequest 1925/ TYPE USNM 38691/ arguta / LECTOTYPE Bryaxis arguta Casey ♂ ‘13, des. DSChandler//. Two Paralectotypes designated: // Mich/ Casey bequest 1925/? arguta -2 PARATYPE USNM 38691/ PARALECTOTYPE Bryaxis arguta Casey ♀ ‘13, des. DSChandler//; //St. Vinc. Penn/ 68/ Casey bequest 1925/? arguta -3 PARATYPE USNM 38691/ PARALECTOTYPE Bryaxis arguta Casey ♂ ‘13, des. DSChandler//.

Figures

FIGURE 23. Brachygluta arguta (Casey). A: Abdomen, dorsal view (holotype). B: Abdomen, caudal view (holotype). C: Right antenna (holotype). D: Left metatibia, anterior view (holotype). E: Aedeagus, internal sac (District of Columbia). F: Aedeagus, internal sac (West Virginia, Kanawha Co.). G: Aedeagus, internal sac (Ohio, Greene Co.). H: Aedeagus, internal sac (Canada, Ontario). I: Aedeagus (paratype).

FIGURE 41. Distribution map of Brachygluta arguta species-group. A: Brachygluta arguta (Casey). B: Brachygluta wickhami Bückle. C: Brachygluta terebrata (Casey) (excluding Canada, Saskatchewan). D: Brachygluta elegans (Brendel) (Red dot: material examined, green dot: only state on label).