Oxyethira sinistra, Santos, Allan Paulo Moreira, Henriques-Oliveira, Ana Lucia & Nessimian, Jorge Luiz, 2009

Santos, Allan Paulo Moreira, Henriques-Oliveira, Ana Lucia & Nessimian, Jorge Luiz, 2009, New species and records of Oxyethira Eaton (Trichoptera: Hydroptilidae) from Amazonas State, Brazil, Zootaxa 2169, pp. 35-44 : 40

Oxyethira sinistra sp. nov.

Figs. 5–8

Diagnosis. This new species has distinctive male genitalia, asymmetrical in general aspect. Segment VIII deeply divided dorsally and ventrally, the long, posterior ventral process from segment IX, and phallus ending in acute curved process, which is crenulate in external margin distinguish the new species.

Description. Male. Length 1.8 mm (n = 2). General color, in alcohol, brown. Antennae stramineous, with 36 segments each, covered by short light brown setae; frontal area of head densely covered with dark brown setae. Wings covered with long dark brown setae; legs with short dark brown setae. Male genitalia. Segment VIII, in dorsal view, with asymmetrical incision mesally ( Fig. 5 ); in ventral view, divided into lateral lobes, left lobe slightly longer than right lobe, both lobes with long stout setae on internal surfaces ( Fig. 6 ); in lateral views, with posterolateral margins each rounded and bearing long stout setae ( Fig. 7 ). Segment IX, in ventral view, subtriangular, blunt anteriorly, extending anteriorly into segment VII, asymmetrical, with anterior apex right of midline, bearing long, slender, posterior ventral process left of midline ( Fig. 6 ), dorsally absent. Segment X indistinct, membranous. Inferior appendages and subgenital plate apparently absent. Bilobed processes long, slightly asymmetrical, right process somewhat shorter than left process, each with spine-like apical seta. Phallus tubular, simple, slightly sclerotized, with short sclerotized subapical process, ending in acute process, curved laterad and with external margin crenulate ( Fig. 8 ).

Female. Unknown.

Remarks. Oxyethira sinistra sp. nov. is somewhat similar to Oxyethira presilla Harris & Davenport, 1999 and O. rareza Holzenthal & Harris, 1992 in the asymmetrical aspect of the male genitalia. But, this new species can be distinguished from these species by presence of bilobed processes and by phallus, which has a short subapical process and apices ending in an acute process with crenulate margin.

Holotype male: BRAZIL: Amazonas: Manaus, Igarapé Arumã, tributary to Rio Cuieiras, 02°30’55.2”S 60°15’44.4”W, 23.viii.2004, J.L. Nessimian & L. Fidelis, light trap ( INPA).

Paratype: BRAZIL: Amazonas: Rio Preto da Eva municipality, tributary to Rio Preto da Eva, 02°32’09.4”S 59°49’59.3”W, 20.iv.2004, J.L. Nessimian, light trap, 1 male ( DZRJ).

Etymology. From Latin sinister (left), referring to the posterior ventral process of segment IX, which is placed on the left side.

Figures

FIGURE 5 – 8. Oxyethira sinistra sp. nov., male genitalia: (5) dorsal view; (6) ventral view; (7) left lateral view; (8) phallus, ventral view. Abbreviations: ven pro IX = ventral process of segment IX; bil pro = bilobed process; pha = phallus. Scale = 0.1 mm.