Polycentropus brevicornutus, Vilarino, Albane & Calor, Adolfo R., 2015

Vilarino, Albane & Calor, Adolfo R., 2015, New species of Polycentropodidae (Trichoptera: Annulipalpia) from Northeast Region, Brazil, Zootaxa 4007 (1), pp. 113-120 : 114-116

Polycentropus brevicornutus new species

Fig. 1 A–F

Diagnosis. This species can be distinguished from all other congeners by the much reduced, almost vestigial intermediate appendage (smaller than the mesolateral and mesoventral processes of the preanal appendage) and by the deltoid inferior appendage with a highly linear lateral aspect. The endothecal sclerotic band has a hooked process, in lateral view similar to that of Polycentropus tripui Hamilton & Holzenthal 2011 , but in dorsal aspect it is narrow in the new species. In addition, the phallotheca is longer and the phallobase is larger.

Description. Male. Length of forewing 5.5–5.8 mm, n=3. Color (in alcohol) of head, thorax, and legs nearly uniformly dark brown. Wings lightly pigmented on M bifurcation and on transversal veins r-m, m, and m-cu.

Genitalia. Sternum IX in lateral view subdeltoid, approximately 2/3 height of segment VIII, anterior margin rounded; in ventral view quadrate, anterior corners broadly rounded, anterior margin shallowly concave, posterior margin shallowly concave. Terga IX + X membranous. Intermediate appendage very reduced, shorter than mesoventral process of preanal appendage, lanceolate. Preanal appendage bipartite, with mesolateral, and mesoventral process; mesolateral process short, broad in lateral aspect, apically rounded, broadly joined to its corresponding mesoventral process basally; mesoventral process directed caudad, approximately 2/3 as long as mesolateral process, apically truncate in dorsal aspect. Inferior appendage bipartite apically, with dorsolateral branch and apicoventral point, and with anterior basal plate extending anterad about 1/3 length of sternum IX; in lateral view moderately short, elongate, deltoid, broad basally, narrowing to acute apex, dorsal margin almost linear, ventral margin rounded; dorsolateral branch subacute in lateral aspect; apicoventral point deltoid, acute, positioned on basal portion medially; in ventral view, inferior appendage broad basally, slightly inflated medially, tapering and curved posteromesad apically, with apicoventral point prominent, acute, heavily setose. Phallobase moderately short; in lateral view, apicoventral projection narrow, slightly longer than apical diameter of phallobase apex, with 1 point; endothecal sclerotic band narrow, ending in hooked dorsal process, apically tapered, strongly sclerotized, and medially divided, tied to broader basal portion; endothecal spines absent; phallotremal sclerite indistinct. Subphallic sclerite indistinct.

Holotype male (alcohol) ( MZUSP): BRAZIL: Bahia: Elísio Medrado, Reserva Jequitibá, GAMBA, Córrego Caranguejo, 12º52’12.7’’S, 39º28’32.4’’W, el. 519 m, 28.iii.2012, UV light pan trap, Calor A.R., Quinteiro F.B., Duarte T., Garcia I.

Paratypes: BRAZIL: Bahia: Varzedo, RPPN Guariru, 12º51’33.1’’S, 39º28’00.9’’W, el. 524 m, 07.ii.2014, UV light pan trap, Calor A.R., Vilarino A., 1 male (alcohol) ( UFBA); Santa Teresinha, Pedra Branca, Córrego das torres, 12º51’02.5’’S, 39º28’80.5’’W, el. 687 m, 06.x.2010, light, Calor A.R., França D., Quinteiro F.B., 1 male (alcohol) ( UMSP).

Etymology. The species epithet is derived from the Latin adjective brevis, -is, -e, short, and adjective cornutus, -a, - um, horned, referring to the short intermediate appendage.

Remarks. Although the subphallic sclerite could not be observed, this species presents all other characteristics that define the P. gertschi Group and also presents the dorsal sclerotized band in the endothecal membrane that places Polycentropus brevicornutus in the Polycentropus jorgenseni Species Complex ( Hamilton 1986). The much reduced intermediate appendage of this species suggests a relationship with the Brazilian species described by Hamilton & Holzenthal (2011) that lack this appendage ( Polycentropus amphirhamphus Hamilton & Holzenthal 2011 , P. cachoeira Hamilton & Holzenthal 2011 , P. inusitatus Hsu & Chen 1996 , P. paprockii Hamilton & Holzenthal 2011 , P. rosalysae Hamilton & Holzenthal 2011 ); however, we could not determine to which species Polycentropus brevicornutus is most closely related.

Figures

FIGURE 1. Polycentropus brevicornutus n. sp. male genitalia: A, left lateral; B, dorsal; C, phallus, dorsal; D, phallus, left lateral; E, caudal; F, ventral (Abbreviations: inf. app. = inferior appendage; int. app. = intermediate appendage; p. pr. app. = process of preanal appendage).