Polycentropus quadricuspidis Hamilton and Holzenthal

Hamilton, Steven W. & Holzenthal, Ralph W., 2005, Five new species of Polycentropodidae (Trichoptera) from Ecuador and Venezuela, Zootaxa 810, pp. 1-14 : 7-9

Polycentropus quadricuspidis Hamilton and Holzenthal , new species

Fig. 3

From Ecuador, P. quadricuspidis n. sp. is placed in the joergenseni complex and is most closely related to P. joergenseni and P. longispinosus . These 3 species share 4 synapomorphies not found in other species of the joergenseni complex: (1) a ventral sclerotized band in the phallic membranes ( Fig. 3 E), (2) a pair of ventral sclerotized bumps in the phallic membrane apical to the ventral band ( Fig. 3 E), (3) an apicoventral process on the phallobase that is reduced to a pair of ventral points ( Fig. 3 E & G), and (4) somewhat broadened and flattened inferior appendages ( Fig. 3 A). The inferior appendage of P. quadricuspidis ( Fig. 3 A & C) is shorter than that of P. longispinosus and resembles that of P. joergenseni . The intermediate appendage ( Fig. 3 A & B) is intermediate between that of P. longispinosus and P. joergenseni in both length and thickness. Polycentropus quadricuspidis is most easily distinguished from these sister species by the 2 pairs of apicoventral points on the phallobase ( Fig. 3 G), the more prominent, spicule­covered pair of ventral bumps in the phallic membranes ( Fig. 3 E), and the slight dorsal concavity of the lateral face of the inferior appendages ( Fig. 3 A).

Adult. Length of forewing: male 9.0 mm (n=2), female 8.0 mm (n=1). Body stramineous, legs stramineous, dorsum of head and thorax brown, clothed with long, dark setae; general vestiture of forewing with fine, brown to dark brown setae, with many small, scattered areas of golden setae, base of forewing with long, erect setae.

Male. Genitalia as in Fig. 3 . Sternum IX in lateral view subquadrate, posterolateral corner slightly produced, in ventral view slightly trapezoidal; anterior margin concave, posterior margin slightly concave. Tergum IX and X membranous. Intermediate appendage sinuate, apex curved medially, long, exceeding preanal appendage by more than 1/2 its length; basal region simple, not expanded; apex acuminate, without apical setae. Preanal appendage short, densely setose, rounded, broad basally; mesoventral process absent. Inferior appendage densely setose, short, subtriangular, wide dorsoventrally, subequal to length; dorsolateral flange broadly rounded; ventrally with dorsally­directed medial point, hidden in lateral view; in ventral view, inferior appendage quadrate; medial point prominent, acute; in caudal view, inferior appendage broadly oval, medial point rounded. Phallobase moderately elongate; apicoventral projection short, broad, with two pairs of points; phallic membranes without spines, but with ventromesal pair of conical, spiculate lobes and dorsal and ventral sclerotized bands; phallic sclerite elongate, apex upturned, spatulate. Subphallic sclerite U­shaped in caudal view.

Holotype male: ECUADOR: Zamora­Chinchipe: 30 km E Loja, el. 2000 m, 23 Sept. 1990, O.S. Flint, Jr. ( NMNH).

Paratypes: Same data as holotype— 1 male, 1 female ( NMNH).

Etymology. From the Latin words quattuor, four, and cuspis, point, for the four points on the apicoventral area of the phallobase.

Figures

FIGURE 3. Polycentropus quadricuspidis, new species. Male genitalia: A—lateral; B—dorsal; C—ventral; D—inferior appendage, caudal; E—phallus, lateral; F—phallic sclerite, dorsal; Gphallobase, caudal; H—subphallic sclerite, caudal.