Polycentropus cachoeira Hamilton & Holzenthal

Hamilton, Steven W. & Holzenthal, Ralph W., 2011, Twenty-four new species of Polycentropus (Trichoptera, Polycentropodidae) from Brazil, ZooKeys 76, pp. 1-53 : 41-43

Polycentropus cachoeira Hamilton & Holzenthal sp. n. Fig. 22

Description.

Polycentropus cachoeira sp. n.has some similarity to other Brazilian Polycentropus of the jorgenseni species complex. Most notable is the general shape of the phallus and its sclerotic endothecal band as well as the shape of the inferior appendage which resembles that of Polycentropus tripui except that it is more elongated in Polycentropus cachoeira sp. n. This species lacks the intermediate appendage and the subphallic sclerite found in other members of the species complex. Polycentropus cachoeira sp. n.is very similar to Polycentropus inusitatus sp. n. in the shape of most of the genitalic structures including a pair of large endothecal spines. The 2 species are reliably separated by details of the preanal appendage and phallus. The mesolateral and mesoventral processes of the preanal appendage are equally long in lateral view and broadly fused in Polycentropus cachoeira sp. n., while in Polycentropus inusitatus sp. n. the mesoventral process is markedly shorter and not so completely fused to the mesolateral process as seen in dorsal view. In Polycentropus cachoeira sp. n., the apicoventral process of the phallobase is undivided and there is an endothecal sclerotic band, whereas in Polycentropus inusitatus sp. n. the apex of the process is divided and the endothecal band is absent.

Adult. Length of forewing (male) 5 mm. Body brown to dark brown; dorsum of head and thorax brown, clothed with long, erect brown setae; base of forewing with long, erect brown setae, general vestiture of forewing with fine brown setae and many patches of pale setae scattered over surface; legs stramineous.

Male. Genitalia as in Fig. 22. Sternum IX in lateral view broadly subtriangular, about 2/3 height of segment VIII; in ventral view slightly trapezoidal, anterior corners very broadly rounded, sides slightly constricted anteriorly, anterior margin nearly straight, posterior margin slightly concave with small, shallow convex medial region. Terga IX + X membranous, dorsum with several long, slender setae. Intermediate appendage absent. Mesolateral process of preanal appendage short, apex rounded, with acute caudal point, at base broadly joined to dorsal 1/2 of mesoventral process; mesoventral process directed caudad, size and shape of mesolateral process, equal in length to mesolateral process. Inferior appendage in lateral view moderately long, rhomboidal; dorsolateral flange low, straight dorsally, with prominent caudomesal spine, exposed in lateral view; mesoventral spine absent; in ventral view inferior appendage quadrate, caudomesal spine prominent, acute. Phallobase moderately elongate; in lateral view apicoventral projection broad, slightly longer than apical diameter of phallobase apex, with 1 point; endothecal sclerotic band very broad, becoming less sclerotized apically; with pair of large endothecal spines; phallotremal sclerite wide in dorsal aspect. Subphallic sclerite absent.

Holotype male:

BRAZIL: Santa Catarina: Urubici, Cachoeira Avencal, 28°02.839'S, 49°36.997'W, 1260 m, 6.iii.1998, Holzenthal, Froehlich, Paprocki (UMSP000033106) (MZUSP).

Paratypes:

same data as holotype, 2 males (UMSP).

Etymology.

Cachoeira is Portuguese for cascade or waterfall, in reference to the habitat where the species was collected.