Isoperla burksi Frison, 1942

Grubbs, Scott A., 2016, Taxonomic Notes On The Eggs Of Eastern Nearctic Isoperla (Plecoptera: Perlodidae: Isoperlinae), Illiesia 12 (8), pp. 35-41 : 37

Isoperla burksi Frison, 1942

Banded Stripetail

( Figs. 1‒6 )

http://lsid.speciesfile.org/urn:lsid: Plecoptera .speciesfile.org: TaxonName:468714

Isoperla burksi Frison, 1942:332 .

Holotype ♂ ( INHS), Lusk Creek, Eddyville , Pope Co., Illinois

Isoperla burksi: Illies 1966:392 , 397.

Isoperla burksi: Poulton & Stewart 1991:47 .

Isoperla burksi: Szczytko & Kondratieff 2015:52 .

Egg. General shape oblong, cross-section concave ( Figs. 1‒2 ), anterior and posterior poles broadly-rounded ( Figs. 2‒4 ). Color pale brown. Collar well-developed, with irregular longitudinal ridges, slightly flared apically ( Fig. 3 ). Follicle cell impressions near collar ranging from elongate to hexagonal ( Figs. 1, 3 ). Chorion covered mostly with irregular-shaped pentagonal or hexagonal follicle cell impressions with thickened elevated ridges ( Figs. 4‒6 ); floors with numerous shallow pits ( Fig. 5‒6 ). Eclosion line present ( Figs. 4‒6 ). Micropyles located along ridges near eclosion line in anterior ¼ ( Figs. 5‒6 ).

Material examined. Alabama, DeKalb Co., South Sauty Creek , 6 km N Rainsville, 34.5484, -85.8543, 7 May 2008, S.A. Grubbs, ♂, ♀ ( WKUC) . Indiana, Jackson Co., Little Salt Creek , 7 km NNW Freetown, 39.0375, -86.1494, 25 May 2002, S.A. Grubbs, 2♀ ( WKUC) . Kentucky, Edmonson Co., Bear Creek , 3 km NW Bee Spring, 37.3029, -86.3204, 6 May 2013, S.A. Grubbs, ♀ ( WKUC) ; Green Co., Big Brush Creek, Bloyd , 37.4049, -85.5758, 27 April 2002, S.A. Grubbs, ♀ ( WKUC) .

Distribution. USA: AL, AR, IL, IN, KY, MD, MO, NC, SC, NJ, OH, OK, SC, VA, WV ( DeWalt et al.

2016).

Diagnosis. Szczytko & Kondratieff (2015) placed this species in the I. burksi group with I. cotta Ricker, 1952 and I. orata Frison, 1942 . Egg characteristics uniting these species include a concave crosssection, well-developed collar, distinct ridges offsetting the cell impressions, and lack of an eclosion line ( Szczytko & Kondratieff 2015). Eggs of I. burksi from Indiana and Kentucky, however, possess a distinct eclosion line ( Figs. 4‒6 ) that easily distinguishes this species from I. cotta ( Szczytko & Kondratieff 2015, figs. 10.14, 10.18) and I. orata ( Szczytko & Kondratieff 2015, figs. 37.9, 37.12). Each of the other three characteristics listed above are exhibited by I. burksi .

Figures

Figs. 1–6. Isoperla burksi. 1–5, Indiana, Little Salt Creek; 6, Kentucky, Big Brush Creek. 1, egg, concave profile, 300X; 2, egg, convex profile, 300X; 3, egg, details of collar, 500X; 4, egg, anterior half, 500X; 5, egg, details of eclosion line and micropyles, 900X; 6, egg, details of eclosion line and micropyles, 750X. mp = micropyles.