Wormaldia occidea (Ross)

Muñoz-Quesada, Fernando J. & Holzenthal, Ralph W., 2008, Revision of the Nearctic species of the caddisfly genus Wormaldia McLachlan (Trichoptera: Philopotamidae), Zootaxa 1838, pp. 1-75 : 46-49

Wormaldia occidea (Ross)

Figures 84–91, 129

Wormaldia occidea (Ross) 1938a: 134 ; fig. 54, male, Oregon, USA (INHS) (as Dolophilus occideus ); Ross 1944: 292; Ross 1949: 155, 156 (transferred to Wormaldia ); Ross 1956: 38, 40, 61, 62, figs. 65 A, B; Denning 1956a: 79; Denning 1956b: 248, fig. 10: 16G; 1958: 94; Fischer 1961: 49; Fischer 1971: 192; Schmid 1982: 31–34, 72 (map 15), figs. 147, 154, 155; Schmid 1998: 215, fig. 110; Armitage 1996: [work not paginated].

Dolophilus cruzensis (Ling) 1938: 64 , male, California (CAS); Ross 1944: 292; Ross 1949: 155, 157 (transferred to Wormaldia ); Ross 1956: 38, 62; Denning 1956a: 79; Denning 1956b: 248, fig. 10: 16E; Denning 1958: 94 (as synonym of W. occidea ).

Ross (1949) placed this species within subgroup 3 of the W. moesta Group. In 1956, he redefined his former species group arrangement and transferred W. occidea to the W. anilla Group, which was retained by Armitage (1996) (Table 1).

This species is closely related to W. anilla ( Ross 1941a) and W. clauseni , new species. However, it can be differentiated from those species by the shapes of sterna VII and IX, tergum X and the inferior appendage, as explained in the diagnoses of those species. Specimens of this species from Benton Co. (Oregon) showed variation in the shape of the posterior margin of tergum VIII from that of the holotype. In those specimens, the posterior margin is relatively straight ( Fig. 89).

Adult. Length of male forewing 5–7 mm (holotype: 5 mm). Head brown, with lighter setae. Antenna long, slender, brown, with small, lighter setae. Maxillary palps yellowish, with lighter setae. Labial palps yellowish, with lighter setae. Dorsum of thorax brown. Legs brown, with small, yellowish setae. Forewing yellowish, covered with fine, small, brown setae, with apical forks I, II, III, IV, and V present ( Fig. 90; Schmid 1982: fig. 147, 1998: fig. 110). Hind wing translucent, with very few fine, small, brown setae, with apical forks I, II, III, and V present ( Fig. 91).

Male genitalia ( Figs. 84–89). Sternum VII with conspicuous, broad, convexly subtriangular, posteromesal process strongly elongate, about 0.5 times length of sternum VIII. Tergum VIII relatively straight or slightly sinuous posteromesally; when viewed laterally, posterodorsal corner truncated or weakly projected. Sternum VIII slightly convex posteromesally. Segment IX, when viewed dorsally, slightly concave anteriorly; when viewed laterally, slender and nearly rectangular in appearance, slightly convex anteriorly, slightly sinuous posteriorly; when viewed ventrally, very weakly concave anteriorly, weakly projected convexly posteriorly with small, truncate, mesal process arising subapically. Segment X, when viewed dorsally, triangularly elongate, narrowest and pointed apically; when viewed laterally, stout, rounded apically. Superior appendages digitate; when viewed dorsally, parallel with segment X, stout, elongate, rounded apically; when viewed laterally, slightly shorter than segment X, narrowly rounded apically. Inferior appendages two segmented; when viewed laterally, basal segment stout, rectangular, elongate, broadest medially, convex dorsally, straight ventrally, apical segment stout, rectangularly elongate, shorter (about 0.9 times) and narrower than basal segment, truncately rounded and narrowest posteriorly; when viewed dorsally, apical segment stout, subtriangularly elongate, narrowest and rounded posteriorly, with oval and apicolateral patch of short, thin, black, spine- shaped setae on inner margin; when viewed ventrally, basal segments paired, united for about their anterior three-quarters, separated posteromesally by a moderately deep and U-shaped emargination, each basal segment robust, widest medially, with outer margin convexly curved anteromedially, apical segment as when viewed dorsally. Phallus, when viewed laterally, pistol-shaped, widest basally, tapering from middle to apex, membranous apically, very lightly sclerotized, with many visible, internal sclerites ( Fig. 88), surrounded by highly convulated membranes.

Material examined. CANADA: British Columbia: Agassiz, 19.v.1927, H.H. Ross, 1 male ( INHS). USA: Alaska: Wrangell-Petersburg Co.: Alvin Bay, Kuiu Isl. , 21.viii.1951, B. Malking, 1 male (in alcohol, INHS); California: Siskiyou Co. : Clear Cr., 6.vi.1965, F. Schmid, 2 males ( CNC); Montana: Missoula Co. : Butler Creek , Snow Bowl , 15.iv.1972, R.A. Haick, 1 male (in alcohol, INHS); same except, 18.v.1972, 3 males, 1 female (in alcohol, INHS); Oregon: Benton Co. : Blodgett , 11.v.1947, B. Malkin, 1 male (in alcohol, INHS); Clackamas Co. : Salmon River , Welches , 18.vi.1933, R.E. Dimick, 1 male ( INHS); Beaver Creek , Mt. Hood , 1.viii.1948, K.M. Fender, 4 males (in alcohol, INHS); Douglas Co. : Clearwater Cr., 8.vi.1965, F. Schmid, 1 male ( CNC); Klamath Co. : Odell Lake , 1.viii.1948, K.M. Fender, 1 male, 2 females (in alcohol, INHS); Holotype: Male, Lincoln Co. : Yew Creek , Alsea Mountains ., 3.v.1936, R.E. Rieder (in alcohol, INHS); Linn Co. : 1 mi [= 1.6 km] W. Marion Fork, N. Santiam Hwy, 9.viii.1952, K.M. Fender, 2 males, 1 female (in alcohol, 2 vials, INHS); Multnomah Co. : Troutdale, 15.iv.1939, S.G. Jewett, Jr., 1 male (in alcohol, INHS); Wallowa Co. : Lostine R., French Forest Camp, Wallowa Mts. , 17.viii.1952, K.M. Fender, 4 males, 1 female (in alcohol, INHS); Yamhill Co. : Peavine Ridge, nr. McMinnville, 5.v.1947, K.M. Fender, 2 males, 1 female (in alcohol, INHS); same except, Sta. 3A, 12.v.1947, K. M. Fender, 7 males, 1 female (in alcohol, INHS); 19.v.1947, 24 males, 4 females (in alcohol, INHS); 23.v.1947, 1 male (in alcohol, INHS); 29.v.1947, 14 males, 2 females (in alcohol, INHS); 2.vi.1948, 8 males, 2 females (in alcohol, INHS); 8.vi.1948, 14 males, 2 females (in alcohol, INHS); 15.vi.1948, 12 males, 5 females (in alcohol, INHS); 16.vi.1948, 1 male (in alcohol, INHS); 17.v.1951, 15 males (in alcohol, INHS); 23.v.1951, 16 males (in alcohol, 2 vials, INHS); 22.v.1952, 4 males, 2 females (in alcohol, INHS); 3.vi.1952, 12 males, 1 female (in alcohol, INHS); 5.vi.1952, 1 male, 3 females (in alcohol, INHS); 9.vi.1952, 1 male (in alcohol, INHS); 25.vi.1952, 13 males, 1 female (in alcohol, INHS); 3.vii.1952, 8 males, 2 females (in alcohol, INHS); 13.vi.1953, 7 males, 5 females (in alcohol, OSAC); Washington: Skagit Co. : Baker Lake , 27.v.1965, F. Schmid, 1 male ( CNC); Whatcom Co. : Shuksan, 25.v.1965, F. Schmid, 5 males ( CNC).

Distribution. Canada: BC. USA: AK (new record), CA, MT, OR, WA.