Chimarra sepikana, Cartwright, 2020

Cartwright, David, 2020, A review of the New Guinea species of Chimarra Stephens (Trichoptera: Philopotamidae), Memoirs of Museum Victoria 79, pp. 1-49 : 44

Chimarra sepikana sp. nov.

Figures 143–145

Holotype. Male (dried, pinned specimen CT-371 figured), PNG, East Sepik Province, Angoram , 28–30 m, about 4° 04' S, 144° 03' E, 14–16 August 1969, J.L. Gressitt ( BPBM).

Other material examined. 1 male (CT-404), PNG, north-east, Bulem River , 64 km north-east Lae, 30 m, about 6° 30' S, 147° 01' E, 29 April 1963, J. Sedlacek ( BPBM) .

Diagnosis. The males of C. sepikana can be separated from all other New Guinea species, including C. aiyura Korboot , C. felholda and C. simbuensis , by the combination of the very weak keel-like ventral process on segment IX, the lateral lobes of segment X which are laterally compressed and the slender, sub-triangular inferior appendages, in lateral view.

Description. General body colour and wings fawn (faded) to light brownish. Wings similar to those of C. ukarumpana (fig. 7). Length of forewing: male 4.4 (specimen CT-404) – 6.2 (specimen CT-371) mm. Forewing with forks 1, 2, 3 and 5 present, Rs slightly sinuous or curved, very slightly thickened, basad of discoidal cell; hind wing with forks 1, 2, 3 and 5 present.

Male. Segment IX anterior margin in lateral view,anteroventrally narrowly rounded, ventral process on segment IX, in lateral view, weakly keel-like, length about 0.2 times basal width, preanal appendages, laterally compressed, rounded in lateral view (fig. 143), appear finger-like in dorsal view (figs 145). Segment X with lateral lobes laterally compressed, aligned alongside phallus, sensilla not discerned (figs 143, 145), in lateral view robust, broadly rounded distally (fig. 143), in ventral and dorsal views appear slender (figs 144, 145). Phallus with no obvious included spines (figs 143–145). Inferior appendages broadest in basal third, tapered gradually distally, slender in distal half, apices directed posteromesally, acute (figs 143, 145), in lateral view angled at about 45° to horizontal, length about 3.5 times width, slender, sub-triangular, dorsal margin mostly straight, ventral margin slightly angled in basal half (fig. 143), in ventral and dorsal views lateral margins curved (figs 144, 145).

Female. Unknown.

Etymology. Sepikana – named for the type locality (Sepik Region of PNG).

Remarks. Chimarra sepikana is known from the holotype male specimen from north PNG. A second male from north-east PNG, about 420 km east of the type locality, is here attributed to C. sepikana , but is smaller and differs slightly in the shape of the lateral lobes of segment X, which are out-turned distally.

Figures

Figures 137–145. Chimarra spp.; 137–139, Chimarra missim sp. nov., male, holotype, genitalia; 137, lateral; 138, ventral; 139, dorsal. 140–142, Chimarra denticulata sp. nov., male, holotype, genitalia; 140, lateral; 141, ventral; 142, dorsal. 143–145, Chimarra sepikana, male, holotype, genitalia; 143, lateral; 144, ventral; 145, dorsal.