Polycentropus amphirhamphus Hamilton & Holzenthal

Hamilton, Steven W. & Holzenthal, Ralph W., 2011, Twenty-four new species of Polycentropus (Trichoptera, Polycentropodidae) from Brazil, ZooKeys 76, pp. 1-53 : 39-41

Polycentropus amphirhamphus Hamilton & Holzenthal sp. n. Fig. 21

Polycentropus new species 8 Hamilton 1986: 149-150, 244; Fig. 7.1.

Description.

This new species is similar to Polycentropus rosalysae in the general shape of the preanal and inferior appendages, lack of intermediate appendage, and the bifurcate apicomesal process of phallobase. The strongly bifurcate and extreme elongation of the apicomesal process of phallobase is the most distinctive feature of Polycentropus amphirhamphus sp. n., separating if from all other Neotropical Polycentropus . Additionally, the inferior appendage lacks the mesoventral spine seen in Polycentropus rosalysae and has a narrower mesoventral process and more ovoid mesolateral process of the preanal appendage compared to that species.

Adult. Length of forewing (male) 5.7-6.6 mm. Body pale brown to yellow; dorsum of head and thorax brown; with long, erect setae, area of long, pale setae on vertex of head, darker on thorax; base of forewing with long, erect dark setae, general vestiture of forewing with fine brown setae and many patches of pale setae scattered over surface; legs brown.

Male. Genitalia as in Fig. 21. Sternum IX in lateral view teardrop-shaped, about 2/3 height of segment VIII; anterior corners broadly rounded, sides very slightly constricted mesally, anteriorly, anterior margin moderately concave, posterior margin slightly concave with small, shallow convex medial region. Terga IX + X membranous. Intermediate appendage absent. Mesolateral process of preanal appendage short, apex broadly triangular, at base broadly joined to dorsal 2/3 of mesoventral process; mesoventral process directed caudad, very broad basally, narrowing rapidly to slender process, slightly exceeding length of mesolateral process. Inferior appendage in lateral view short, generally round; dorsolateral flange low, rounded dorsally, with prominent caudomesal spine, partially exposed in lateral view; mesoventral spine absent; in ventral view inferior appendage approximately oval, caudomesal spine prominent, rounded. Phallobase moderately elongate; with paired apicolateral, blade-like, decurved processes on each side of slightly compressed phallobase apex; endothecal sclerotic band absent; endothecal spines absent; phallotremal sclerite narrow in dorsal aspect. Subphallic sclerite absent.

Holotype male:

BRAZIL: Rio de Janeiro: Nova Friburgo, municipal water supply, 950 m, 20.iv.1977, C.M. & O.S. Flint, Jr. (UMSP000131231) (in alcohol). (NMNH).

Paratypes:

BRAZIL: same data as holotype, 1 male (in alcohol) (NMNH); same, except 24.iv.1977, 1 male (NMNH); Santa Catarina: Urubici, Morro da Igreja, Cachoeira Veu da Noiva, 28°04.595'S, 49°31.090'W, 1300 m, 5.iii.1998, Holzenthal, Froehlich, Paprocki, 2 males; São Paulo: Parque Estadual de Campos do Jordão, Rio Galharada, 22°41.662'S, 45°27.783'W, 1530 m, 13-15.ix.2002, Blahnik, Prather, Melo, Huamantinco, 6 males (UMSP), 1 male (in alcohol) (MZUSP); Estação Biológica Boraceia, Rio Venerando, 23°39.185'S, 45°53.414'W, 850 m, Blahnik, Prather, Melo, Froehlich, Silva, 1 male (in alcohol) (UMSP).

Etymology.

From the Greek amphi for double and rhamphos for a curving beak or bill, in reference to the long, paired beaklike processes on the phallobase of the male genitalia.