Prostoia hallasi Kondratieff & Kirchner

Grubbs, Scott A., Baumann, Richard W., DeWalt, R. Edward & Tweddale, Tari, 2014, A review of the Nearctic genus Prostoia (Ricker) (Plecoptera, Nemouridae), with the description of a new species and a surprising range extension for P. hallasi Kondratieff & Kirchner, ZooKeys 401, pp. 11-30 : 14-15

Prostoia hallasi Kondratieff & Kirchner Figs 17-24, 42

Prostoia hallasi Kondratieff & Kirchner, 1984: 579. Holotype ♂ (USNM), Washington Ditch, City of Suffolk, Virginia

Material examined

(also provided in Suppl. material 1). USA, Connecticut, New Haven Co., Hammonasset River, Killingworth, 41.3573, -72.6126, 1 May 1988, W.G. Downs, 3♂, 25♀ (BYUC). Georgia, Crisp Co., Gum Creek, Hwy 257, 32.0066, -83.7374, 30 March 1993, B.A. Caldwell, 2♂, 2♀, 2 nymphs (BYUC). Illinois, Pope Co., tributary to Alcorn Creek, 7.1 km NW Hamletsburg, 37.1777, -88.4953, 2 March 2012, R. E. DeWalt, 2♂, 2♀ (INHS), tributary to Alcorn Creek, 15 km NE Brookport, 37.1777, -88.4891, 17 March 2013 (reared, from nymphs collected 14 March 2013), S.A. Grubbs & J.M. Yates, 2♂, 2♀, 4 nymphs (WKUC), same site, 3 April 2013, S.A. Grubbs & J.M. Yates, 2♀ (WKUC). Massachusetts, Unknown County, "Boston Reg.", 2 May 1936, L.J. Milne, 3♀ (USNM). Virginia, Essex Co., 1 mi SE Dunnsville, 37.8504, -76.8083 (malaise trap), 17-29 April 1992, D.R. Smith, 4♂, 110♀ (BYUC, USNM); same site, 26 March– 8 April 1994, D.R. Smith, 4♂, 9♀ (BYUC, USNM); Falls Church City, Falls Church, 11 February 1941, J.F. Hanson, ♂ (USNM); Southhampton Co., Tarrara Creek, Hwy 666, 36.5952, -77.2274, 10 March 1991, R.W. Baumann & R.F. Kirchner, 2♂ (BYUC); Suffolk City, Washington Ditch, off Washington Ditch Road, Dismal Swamp, 36.6442, -76.5471, 2 March 1983, B.C. Kondratieff, 2♂, ♀ (paratypes; BYUC); Washington Ditch, Dismal Swamp, 36.6442, -76.5471, 10 March 1991, R.W. Baumann & R.F. Kirchner, 48♂, 54♀ (BYUC).

Distribution.

USA: NC, VA ( DeWalt et al. 2013), CT, GA, IL, MA (New state records).

Remarks.

This species was once considered unique amongst Nearctic Nemouridae in that it was known only from low gradient coastal streams in the Great Dismal Swamp ( Kondratieff and Kirchner 1984, Kondratieff et al. 1995). The discovery of localities north in New England and south to Georgia was not too surprising since these are range extensions along the Atlantic Coastal Plain (Fig. 42). This species should eventually be found in coastal regions within the intervening states (i.e. Delaware, Maryland, New Jersey, New York, Pennsylvania, and South Carolina).

We initially anticipated that the populations from the Shawnee Hills region of southern Illinois represented an undescribed species. Both Illinois sites were small, upland tributaries ca. 1 m wide and very distinct from the description of the type locality ( Kondratieff and Kirchner 1984). Yet the SEM images of the epiproct from specimens from several locations, particularly of the complex ornamentation of the terminus of the ventral sclerite, showed unexpected across-site similarity and no evidence that the southern Illinois populations represented an undescribed species. The epiproct terminus of the populations from Essex Co., Virginia (Fig. 17), coastal Connecticut (Fig. 20), southern Illinois (Fig. 21) and the type locality in eastern Virginia ( Kondratieff and Kirchner 1984, their Fig. 6) appear indistinguishable as such: the distal anterior tip is slightly bifurcate, a small ventral subterminal knob is present, and the subterminal forked structure includes paired, ventrally-directed triangular processes and paired somewhat dorsally-directed subtruncate processes. Females from southern Illinois were indistinguishable from those from the Connecticut and Essex Co., Virginia (Fig. 24) localities noted above.