Wormaldia lacerna Denning

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 : 33-34

Wormaldia lacerna Denning

Figures 53–59, 130

Wormaldia lacerna Denning 1958: 93 , 94, figs. 2 A–C, male, Washington, USA (CAS); Fischer 1971: 191; Armitage 1996: [work not paginated].

Denning (1958) placed this species within the W. moesta Group, as defined by Ross (1956) for this genus and accepted by Armitage (1996) (Table 1).

This species is similar to Wormaldia moesta ( Banks 1914) , but differing by the shapes of tergum VIII, sterna VIII and IX, and the inferior appendage. Tergum VIII in W. lacerna has a U-shaped emargination posteromesally. Tergum VIII in W. moesta is slightly sinuous or slightly straight posteromesally. Sternum VIII in W. lacerna is slightly sinuous posteriorly with a convexity mesally. Sternum VIII in W. moesta has an elongate and digitate process posteromesally. Sternum IX in W. lacerna is weakly projected convexly posteriorly with a shallow concavity mesally. Sternum IX in W. moesta has a slender and subtriangular process posteromesally. When viewed laterally, the apical segment of the inferior appendage in W. lacerna is strongly elongate, longer than the basal segment, slightly concave dorsomedially, and with the apex extended and slightly projected posterodorsally. The apical segment of the inferior appendage in W. moesta is elongate, equal in length to the basal segment, straight medially, and the apex is narrowest and truncately rounded. Otherwise, W. lacerna is similar to W. gabriella , but can be differentiated as detailed in the diagnosis of that species.

Adult (in alcohol). Length of male forewing 6 mm (holotype). Head brown, with yellowish setae. Antenna long, slender, yellowish, with small, brown and yellowish rings of small setae. Maxillary palps light brown, with lighter setae. Labial palps light brown, with lighter setae. Dorsum of thorax brown. Legs light brown, with small, yellowish setae. Forewing yellowish, covered with fine, small, light brown setae, with apical forks II, III, IV, and V present ( Fig. 58). Hind wing translucent, with very few fine, small, brown setae, with apical forks II, III, and V present ( Fig. 59).

Male genitalia. ( Figs. 53–57). Sternum VII with conspicuous, digitate, posteromesal process strongly elongate, about 0.5 times length of sternum VIII, rounded apically. Tergum VIII straight posteriorly with conspicuous, U-shaped, mesal emargination. Sternum VIII sinuous posteriorly with wide and mesal convexity. Segment IX, when viewed dorsally, deeply concave anteriorly; when viewed laterally, broadest ventrally and nearly subrectangular in appearance, convex anteriorly, nearly straight posteriorly; when viewed ventrally, slightly concave anteriorly, slightly convexly projected posteriorly with shallow, mesal concavity. Segment X, when viewed dorsally, triangularly elongate, slightly bulged medially, narrowly rounded apically; when viewed laterally, slender, rounded and weakly produced apicodorsally. Superior appendages digitate; when viewed dorsally, parallel with segment X, stout, elongate, rounded apically; when viewed laterally, nearly equal in length to segment X, tubularly elongate. Inferior appendages two segmented; when viewed laterally, basal segment broad, subrectangular, elongate, broadest and convex medially, apical segment stout, rectangular, strongly elongate, longer (about 1.3 times) and narrower than basal segment, slightly concave and narrowest medially, produced and widely rounded posterodorsally; when viewed dorsally, apical segment as in ventral view; when viewed ventrally, basal segments paired, united for about their anterior three-fifths, separated posteromesally by a deep and U-shaped emargination, each basal segment robust, widest medially, with outer margin slightly convexly curved, apical segment stout, slightly incurved medially, narrowest and subovate posteriorly, with elongate and apicolateral patch of short, thin, black, spine-shaped setae. Phallus, when viewed laterally, pistol-shaped, widest basally, tapering from middle to apex, membranous apically, very lightly sclerotized, with single visible, spear-shaped, internal sclerite ( Fig. 57).

Material examined. USA: Washington: Holotype: Male, Klickitat Co.: Satus Creek , near Goldendale, 2.x.1952, D.G. Denning (in alcohol, CAS).

Distribution. USA: WA.