Megarcys irregularis ( Banks 1900 )

Stewart, Kenneth W. & Kondratieff, Boris C., 2012, Larvae Of The Nearctic Species Of The Stonefly Genus Megarcys Klapálek (Plecoptera: Perlodidae), Illiesia 8 (3), pp. 16-36 : 20-23

publication ID	https://doi.org/ 10.5281/zenodo.4760667
DOI	https://doi.org/10.5281/zenodo.4762541
persistent identifier	https://treatment.plazi.org/id/C250BC3D-FFBC-FF9C-FC0C-3D40FDE94119
treatment provided by	Felipe
scientific name	Megarcys irregularis ( Banks 1900 )
status

Treatment

Megarcys irregularis ( Banks 1900) View in CoL

( Figs. 12 View Figs , 24 View Figs , 30 View Figs , 36 View Figs , 42 View Figs , 48 View Figs , 60 View Figs , 70 View Figs , 84 View Figs a-b, Table 1 View Table 1 )

Distribution. Pacific Northwest; Coastal and Cascade Mountains of Washington, British Columbia.

Material examined. Washington: Pierce Co., Fryingpan Creek, Sunrise Road , Mount Rainier National Park , 13-VII-2003, B. Kondratieff, J. Schmidt, 1♂, 2♀ larvae; 14-VII-2004, B. Kondratieff, 5♀; Nisqually River , Longmire, Mount Rainier National Park, 28-V-1997, B. Kondratieff, 2♂, 1♀, 2♂ larvae; White River , Hwy. 410, Mount Rainier National Park, B. Kondratieff, 8♂, 1♀, 3♂ larvae, 3♀ larvae, 1♂ exuvium, 2♀ exuviae; 20-VI-2003, B. Kondratieff, R. Zuellig, J. Schmidt, 2♀.

Characters. Head capsule width ♂ 3.06-3.30mm, ♀ 3.90-4.62mm; pronotal width ♂ 2.88-3.12mm, ♀ 3.36- 4.08mm; body length ♂ 18.3-19.5mm, ♀ 19.5-24.0mm ( Table 1 View Table 1 ). Color and pigmentation ( Figs. 12 View Figs , 24 View Figs , 30 View Figs , 36 View Figs , 42 View Figs , 48 View Figs ), lacinia, and dorsomesal band of erect silky white hairs typical of genus. Wingpads of ♂ and ♀ macropterous. Gill number and arrangement typical of genus ( Fig. 70 View Figs ). Submental gill length ♂ 0.12- 0.42mm, ♀ 0.36-0.45mm; anterior supracoxal gill length ♂ 0.27-0.42mm, ♀ 0.36mm ( Table 1 View Table 1 ). Legs ( Fig. 30 View Figs ) with setation typical of genus as described by Stewart & Stark (2002).Y-arms of mesosternum ( Fig. 36 View Figs ) typical of genus. Cercal segments ♂ 24-26 ( Table 1 View Table 1 ), with setation typical of genus. Developing membranous, windsocklike process of male epiproct ( Figs. 42 View Figs , 48 View Figs , 70 View Figs ) evident in late instar individuals, and pointed posteroventrally in lateral view ( Fig. 79 View Figs ).Developing female subgenital plate of 8 th sternum ( Figs. 49 View Figs , 84a, b View Figs ) shallowly notched mesally.

Comments. The generic characters proposed by Stewart & Stark (2002), based solely on M. signata , are reaffirmed in this species, and color and pigmentation fit the generic pattern illustrated herein for M. signata . The measured gill lengths and shapes were greatly variable in this species ( Table 1 View Table 1 ), and otherwise similar to M. signata .