Helicopsyche (Petrotrichia) ninakosha, Johanson, Kjell Arne & Oláh, János, 2006

Johanson, Kjell Arne & Oláh, János, 2006, Eleven new species of Sericostomatoidea from Madagascar (Trichoptera: Helicopsychidae, Petrothrincidae, Sericostomatidae), Zootaxa 1205, pp. 1-30 : 8-9

Helicopsyche (Petrotrichia) ninakosha , new species

Figs 12–16 , 58

This new species is morphologically close to H. sahadika , new species in that the pronotal setal warts are similarly modified into a single, wide wart. In genitalic features, the two species are very similar: both have segment IX highly reduced, forming a very narrow plate ventrally; they have Xth tergum simple, a strong and very long spine apically on the gonocoxite, and the ventral branch of the gonocoxite modified. The last similarity is, however, very differently expressed in the two species and they are easily distinguished from each other by the shape of the ventral branch of the gonocoxite in both lateral and ventral aspects.

Male head and thorax ( Fig. 12 ). Scape about 2.5x longer than wide. Second segment of maxillary palp about 2x longer than basal segment ( Fig. 12 ). Interantennal warts slightly separate from each other, cephalic warts nearly triangular, one pair of postantennal warts small and rounded, and postocular warts not conspicuous. Pronotum with paired setal warts completely fused medially into a single transverse wart. One pair of oval setal warts present on mesoscutum.

Male wings ( Fig. 13 ). Forewing length 2.7 mm, hind wing length 2.2 mm. Denuded wing membrane pale flavous with veins pale helvus. Venation similar to H. anomana Johanson and H. giboni Johanson. On forewing R5 originating immediately distally to crossvein R3­R4. M and Cu separate a longitudinal groove containing sensilla and reaching the wing margin. Discoidal cell about 1/5 the wing length.

Male abdomen and genitalia ( Fig. 14–16 ). Abdominal reticulation absent. VIth sternal process well developed. Segment IX strongly narrowed anteroposteriorly and slightly thicker at dorsal half ( Fig. 14 ); anterior margin with short, slightly pointed dorsal anterior lobe; posterior margin slightly produced into triangle opposite to anterior lobe; narrow in ventral ( Fig. 16 ) and dorsal view ( Fig. 15 ). Superior appendage fused with tergum IX and originating at posterodorsal corner of segment IX, finger­like, straight and oriented posterodorsad. Tergum X forms a pair of diverging, falciform plates, well separated in dorsal view ( Fig. 15 ), inner lobe tapering in lateral aspect ( Fig. 14 ). Gonocoxite primary branch forms a simple, weakly curving rod, its distal end armed with a subapical strong and long spine. The ventral branch of the gonocoxite forms a long, parallel­sided process, spiralling strongly towards and above phallus ( Figs 14, 16 ). Phallus basally broad, divided into a nearly uniformly thick ventral process and a dorsal branch that is about 2x broader than the ventral process and has three subapical setae below the spinose apex ( Fig. 14 ).

Etymology. Named after the very specialised, spiralling shape of the ventral branch of gonocoxite. In Sanscrit, “ ninakosha ” means spiral.

Holotype male: MADAGASCAR: Demongloy, Mananteina Fort, Dauphin District. Xii. 1948 [Hoogstraal] (MNHN, in alcohol).

Figures

FIGURE 58. Map of Madagascar showing distributions of Helicopsyche spp. (Helicopsychidae): H. ambodiva (circle); H. ninakosha and H. sahadika (rectangle); H. giboni (diamond); and H. anomana (triangle).

FIGURES 12 – 16. Helicopsyche (Petrotrichia) ninakosha, new species, holotype. 12 — head and thorax, dorsal; 13 — right wing pair; 14 — genitalia, lateral; 15 — genitalia, dorsal; 16 — genitalia, ventral.