Hemiquedius infinitus Brunke & Smetana

Brunke, Adam, Smetana, Ales, Carruthers-Lay, Duncan & Buffam, Joel, 2017, Revision of Hemiquedius Casey (Staphylinidae, Staphylininae) and a review of beetles dependent on beavers and muskrats in North America, ZooKeys 702, pp. 27-43 : 32-34

Hemiquedius infinitus Brunke & Smetana sp. n. Figs 1C, 2C,D,G, 3B, 4 map

BINs (shared with H. castoris ).

BOLD:ACL9384 + BOLD:ABW6323

Type Locality.

3 mi northwest of Orange, Orange County, Texas.

Type material.

Holotype (♂, CNC). Tex. Orange Co., 3 mi NW Orange, 17.IV.1976, A. Smetana [dissected parts mounted on card].

Paratypes.

(13 ♂ 17 ♀ CNC, 1 ♂ 4 ♀ DEBU, 1 sex? BIO, 1 ♀ TAMU, 1 ♀ MEM, 6 ♂ 7 ♀ FMNH): CANADA: Ontario: Haldimand-Norfolk Region: ~6 km W of St. Williams, Cronmiller prop., 42°40'21"N, 80°29'26"W, forest pools, 5.VII.2011, A. Brunke, debu01149192, debu01146692 (2, DEBU); Backus Woods, north block, treading vernal pools, 42°40'7"N, 80°29'34"W, 23.IV.2011, Brunke and Marshall, debu00340010 (1, DEBU); Long Point, woodlot jct Hwys 24 & 59, leaf litter at very edge of temp pond, 21.IV.1973, H. Frania (1, CNC); Lanark County: 13 km S of Smith’s Falls, 17.V.1981, J. M. Campbell (1, CNC); Leeds and Grenville County: 4 km N of Westport, 26.V.1981, A. Davies (1, CNC); Ottawa Region: Ottawa (1, CNC); 8 km N Limoges, Larose Forest, 45.388°N 75.228°W tread marshy vegetation around ponds, 81 m, 23.VI.2016, A. Brunke and A. Davies (1, CNC). Prince Edward Co.: Brimley, 28.IV.1946 (2, CNC); same except 8.V.1946 (1, CNC); same except 9.V.1943 (1, CNC); same except 12.V.1954 (1, CNC); same except 29.IX.1943 (1, CNC); same except 7.V.1933 (1, CNC); Wellington Co.: Conc. 11 and Hume Rd, 43.537 -80.134, 27.X.2010, P. Hebert, sample ID BIOUG01310-E07 (1, BIO); Guelph, 4.VI.1985, B. Longpre, (1, DEBU); Guelph, University Arboretum, cedar swamp, 18.IV.2009, A. Brunke, debu00305699 (1, DEBU); Rockwood (1, CNC). Quebec: Communauté-Urbaine-de-Quebec: Quebec, 2.X.1969, C. Chantal (1, FMNH); Montérégie Reg.: Philipsburg, 19.IX to 12.X.1972, Dondale and Redner (1, CNC).

United States: Alabama: Mobile County: Mt. Vernon, 20.III.1932, H. Dietrich (1, CNC). Arkansas: Union County: Backwaters of Grand Marais Lake, under debris, 9.VII.1974, R. G. Chenowith, CNC656112, BOLD Proc ID CNCCT065-17 (1 CNC), 10 mi S El Dorado, Little Cornie Bayou, treading, 20.V.1974 (1, FMNH). Florida: Okaloosa County: Fort Walton Beach, 18.III.1976, E.J. Kiteley (1, CNC). Illinois: McHenry County: Moraine Hills State Park, litter at log, 7.IV.1984, L.E. Watrous (1, FMNH); Union County: 1 mi E of Wolf Lake, 8.V.1976, A. Smetana, CNC656110, BOLD Proc ID CNCCT069-17 (2, CNC). Indiana: Porter County: Tremont, 14.IV.1938 (1, FMNH). Louisiana: state record only (1, FMNH). Massachusetts: Middlesex County: Sherborn, 26.VIII.1934, C.A. Frost (1, CNC); same except 16.X.1881 (1, CNC). Michigan: Berrien County: Warren Woods, Lakeside, 6.V.1969, W. Suter (1, FMNH). Mississippi: Oktibbeha County: Noxubee N.W. Refuge, 33.290 -88757, alpha-pinine baited Lindgren funnel, bottomland hardwood forest, 21-29.VII.2009, J.G. Hill & J. Seltzer (1, MEM). New Jersey: Bergen County: River Vale, 25.V.1980, P.J.D (1, CNC); Sussex County: Hopatcong (1, CNC); state record only, Schwarz (1, FMNH). New York: Long Island: Queens, 18.X.1924, F.M. Schott (1, CNC); Richmond County: Staten Island, Concord (1, CNC); Seneca County: Willard, V.1970, R. Lenczy (1, FMNH); Westchester County: Yonkers, 29.III.1941 (1, FMNH). South Carolina: Dorchester County: Francis Beidler Forest, 10 km NE Harleyville, bald cypress swamp, FIT, 1-9.V.1987, CNC656111, BOLD Proc ID CNCCT068-17 (1, CNC); Orangeburg County: Orangeburg, The Methodist Oaks, 33.419 -80.858, Berlese wet leaf litter in wetland, 27.III.2010, J. & S. Cornell (4, FMNH). Texas: Houston County: 11 mi E Ratcliff, 24.IV.1976, A. Smetana, CNC656109, BOLD Proc ID CNCCT064-17 (2, CNC); Orange County: 3 mi NW Orange, 17.IV.1976, A. Smetana, CNC656108, BOLD Proc ID CNCCT063-17 (1, CNC); Trinity County: 12 mi SW Lufkin, 22.IV.1976, A. Smetana (1, CNC); Tyler Co.: Kirby State Forest, 30.575 -94.417, ground level FIT, 9-30.III.2003, E. Riley (1, TAMU).

Diagnosis.

Hemiquedius infinitus can be distinguished by a combination of the elytral disc without fine dense setae (Fig. 1C), pronotum with PW/PL ≥ 1.00 (Fig. 3B) and the indistinct or absent emargination of male sternite VIII (as in Fig. 1E). Hemiquedius infinitus and H. castoris cannot be distinguished by their CO1 barcodes.

Description.

Measurements ♂ (n = 5): HW/HL 1.15-1.21; PW/PL 1.00-1.05; EW/EL 0.92-0.95; ESut/PL 0.72-0.79; PW/HW 1.19-1.27; forebody length 5.24-5.53 mm.

Measurements ♀ (n = 5): HW/HL 1.17-1.21; PW/PL 1.00-1.04; EW/EL 0.91-0.94; ESut/PL 0.75-0.77; PW/HW 1.21-1.27; forebody length 5.30-5.87 mm.

Extremely similar to H. castoris and differing only in the following: elytral disc without fine dense setae (Fig. 1C); scutellum with shallow microsculpture in small fragments or with, at most, entire disc except margins with shallow meshed microsculpture; head not sexually dimorphic; pronotum slightly more elongate on average (Fig. 3B); paramere more strongly constricted at base forming a more rounded lobe (Fig. 2G).

Etymology.

The species epithet means unbounded in Latin and refers to the occurrence of this species in a variety of wetland habitats, though not inside the lodges of beavers or muskrats.

Distribution.

Figure 4. This species is currently known from a wide area of eastern North America: southern Ontario and Quebec, south to the Florida panhandle, west to Texas and north to northern Michigan. Its distribution corresponds well with that of the eastern deciduous forest. All data from Smetana (1971a) can technically be associated with this species except two specimens from peninsular Florida and two from Quebec, with setose elytra.

Bionomics.

Specimens have been collected from a variety of wetland edge habitats ranging from open eutrophic ponds to shaded vernal forest pools.

Comments.

Hemiquedius infinitus is most similar to H. castoris but can be easily distinguished based on the lack of fine dense setae on the elytral disc. The genitalia of these two species are extremely similar, variable and only differ by the shape of the paramere. At present H. infinitus is not known to be sympatric with H. ferox but may overlap with it in northern Florida.