Oxyethira redunca Thomson & Holzenthal

Thomson, Robin E. & Holzenthal, Ralph W., 2012, New species and records of Hydroptilidae (Trichoptera) from Venezuela, ZooKeys 185, pp. 19-39 : 25-26

Oxyethira redunca Thomson & Holzenthal sp. n. Fig. 8

Diagnosis.

We have been unable to assign this species to a subgenus. The deep ventral excision of abdominal segment VIII and the extension of segment IX anteriorly into segment VII make it somewhat similar to Loxotrichia . However, the absence of a subgenital process precludes it from being placed with certainty in any of the current subgenera and distinguishes it from all other species.

Description.

Male. Length of forewing 2.4 mm (n=1). Head unmodified, with 3 ocelli; antennae unmodified. Tibial spur count 0, 3, 4. Dorsum of head brown with pale yellow setae; thorax brown with pale yellow setae dorsally, pale yellow ventrally; leg segments with brown setae. Forewings covered with fine brown setae and elongate patches of light brown setae and small patches of dark brown setae near margins and apex. Genitalia. Abdominal sternum VII with spatulate mesoventral process. Segment VIII anterolateral margin straight, posterolateral margin acutely convex; dorsally posterior margin with deep acute emargination; ventrally posterior margin with deep rounded emargination. Segment IX anterolateral margin very elongate, narrowing, withdrawn into segments VII–VIII, posterolateral margin acute, not extending past segment VIII; dorsally bearing paired, elongate, slender processes, basal half extending posteriorly, apical half strongly bent anteriad. Subgenital process not apparent. Bilobed process not apparent. Inferior appendage setose, laterally narrow and rod-like, fused latero-ventrally with subgenital appendages, ventrally with semiquadrate apical emargination. Tergum X membranous, large, bearing elliptic patch of minute setae dorsally (see Fig. 8B). Phallus with tubular basal half, apical half membranous, convex ventrally, apex curving dorsad.

Material examined.

Holotype male:VENEZUELA: Bolívar: Gran Sabana, E. Pauji, “Río Curvita", 4°31.237'N, 61°31.591'W, 869 m, 15-16.vii.2010, UV light, Holzenthal, Thomson, Cressa (UMSP000095176) (UMSP).

Etymology.

The Latin word reduncus meaning "bent backward", referring to the sharply bent dorsal processes of segment IX.