Wormaldia pachita 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 : 51-53

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Wormaldia pachita Denning


Wormaldia pachita Denning

Figures 96–100, 132

Wormaldia pachita Denning 1956a: 78 , 79, figs. 6 A–C, male, California, USA (CAS); Denning 1956b: 248, 269, fig. 10: 37; Fischer 1971: 195; Armitage 1996: [work not paginated].

Denning (1956) placed this species within the W. moesta Group proposed by Ross in 1949. However, Ross (1956) reconsidered his previous proposal for this species group. According to Ross (1956) and Armitage (1996), W. pachita should belong within the W. anilla Group (Table 1).

This species and Wormaldia birneyi are similar to W. shawnee ( Ross 1938a) and W. strota ( Ross 1938b) , but are distinguishable from those two species and the other Nearctic Wormaldia by the widely divergent basal segments of the inferior appendages when viewed ventrally. In W. birneyi these basal segments are incurved and considerably narrow and elongate. Finally, W. pachita can be identified from W. birneyi by the shapes of sterna VII and IX, and the inferior appendage, as discussed in the diagnosis of that species.

Adult (in alcohol, male holotype) Head light brown, with lighter setae. Maxillary palps yellowish, with lighter setae. Labial palps yellowish, with lighter setae. Dorsum of thorax light brown. Legs yellowish, with small, lighter setae.

Male genitalia ( Figs. 96–100). Sternum VII straight posteriorly without process mesally. Tergum VIII shallowly sinuous posteriorly. Sternum VIII slightly concave anteriorly, straight posteriorly without process mesally. Segment IX, when viewed dorsally, concave anteriorly; when viewed laterally, slender and nearly Cshaped in appearance, convex anteriorly, concave posteriorly, when viewed ventrally, concave anteriorly, strongly projected sinuously posteriorly with elongate, slender, mesal process arising preapically. Segment X, when viewed dorsally, triangularly elongate, narrowest and rounded apically; when viewed laterally, slender and pointed. Superior appendages digitate; when viewed dorsally, parallel with segment X, stout, elongate; when viewed laterally, slightly shorter than segment X, slender, rounded apically. Inferior appendages two segmented; when viewed laterally, basal segment stout, rectangular, strongly tubularly elongate, convex anteriorly, apical segment slender, tubular appearance, strongly elongate, longer (about 1.4 times) and narrower than basal segment, weakly upcurved medially, widened and rounded posteriorly; when viewed dorsally, apical segment as in ventral view; when viewed ventrally, basal segments paired, united for about their anterior one-third, separated posteromesally by a prominent, strongly deep, broad, V-shaped emargination, each basal segment stout, widest anteromedially, clearly incurved, apical segment, slender, tubularly elongate, inner margin very weakly concave, slightly widened and rounded posteriorly, with small, oval, apicolateral apical patch of short, thin, black, spine-shaped. Phallus, when viewed laterally, pistol-shaped, widest basally, tapering from middle to apex, membranous apically, very lightly sclerotized, with various visible, internal sclerites ( Fig. 100).

Material examined. USA: California: Holotype: Male, Nevada Co.: Grass Valley , 2350 ft [= 716 m], 5.v.1946, H.P. Chandler (in alcohol, CAS).

Distribution. USA: CA.


California Academy of Sciences














Wormaldia pachita Denning

Muñoz-Quesada, Fernando J. & Holzenthal, Ralph W. 2008

Wormaldia pachita

Fischer, F. C. J. 1971: 195
Denning, D. G. 1956: 78
Denning, D. G. 1956: 248