Mecynostomella sigma, Johanson, 2003

Johanson, Kjell Arne, 2003, Revision of the New Caledonian genus Mecynostomella (Trichoptera, Kokiriidae), Zootaxa 270 (1), pp. 1-24 : 17-18

Mecynostomella sigma sp.n.

( Figs 41­45 , 53 )

Material examined: Male holotype: E Col d'Amieu Forestry Station, 320 m, 17.vi.1971 (#26) [J.D. Holloway] ( ROM, alcohol) .

Etymology: sigma , from the Latin letter S ( sigma ), referring to the shape of the gonocoxite. To be treated as a noun in apposition.

Diagnosis: M. sigma has a pale area in the forewings as in hollowayi . In sigma , the lateral branches are sub­straight and short, and the median branches proceed the lateral branch apices.

Male.

Colors faded. Antennal flagellum broken.

Thorax: Pronotum with few dorsolateral, stout, dark brownish setae confined to large, distinct warts.

Wings: Forewing length 11.3 mm (n=1), hind wing length 9.8 mm (n=1). Forewings pale brownish; distinct pale area between Cu and A as in hollowayi (in Fig. 6 ). Hind wing pale grey. Venation as described for genus

Genitalia ( Figs 41­45 ): Segment IX, lateral view ( Fig. 41 ), about 2.1x higher than long; anterior part shallowly produced, margin smoothly rounded; dorsal margin rounded; posteroventral margin with wide, anteriorly sub­straight incision ( Fig. 43 ). Segment X simple; in dorsal view ( Fig. 42 ), central branch nearly parallel­sided at distal half; in lateral view ( Fig. 41 ), nearly parallel­sided proximally, tapers distally; dorsal margin bent ventrally at mid­way; apex covered by setae, few setae present on lateral margin; segment X nearly 2x longer than high ( Fig. 41 ); apex narrowly rounded in lateral view, deeply incised in dorsal view ( Fig. 42 ). Lateral branch length half the central branch length, pointed, sub­straight ( Fig. 41 ); slightly converging in dorsal view ( Fig. 42 ); proximal setae form continuous band with setae on segment IX. Median branch, lateral view ( Fig. 41 ), large, proceeds lateral branches; with setae on ventral margin; in dorsal view ( Fig. 42 ), sharply pointed, visible between lateral and central branches. Gonocoxite, lateral view ( Fig. 41 ), curving slightly dorsally along its length, apex produced dorsad; dorsal margin sigmoid, ventral margin slightly convex ( Fig. 41 ); slender sub­apical part nearly 0.6x as high as proximal part; in ventral view ( Fig. 43 ), sub­straight, oriented posteriad along its length, apex slightly dilated; covered by setae except on proximal part. Phallus simple; phallobase slightly longer than three­quarts the height of segment IX ( Fig. 44 ); endotheca produced dorsally in dorsal opening starting distally on phallus, without spines; in ventral view ( Fig. 45 ), lateral incisions at proximal part located opposite to margin of anterior phallus opening.

Female unknown.

Figures

FIGURES 41­45. Mecynostomella sigma sp.n., male holotype. 41, genitalia, lateral view; 42, genitalia, dorsal view; 43, genitalia, ventral view; 44, phallus, lateral view; 45, phallus, ventral view.

FIGURES 53­54. Distribution maps of New Caledonian Mecynostomella. 53, caledonia (circles), hollowayi (rectangles), and sigma (triangle); 54, spinosa (circles), flinti (rectangle), brevis (triangles), and fusca (diamond).

FIGURES 6­14. Mecynostomella species, right wings and wing details. 6, Mecynostomella spinosa sp.n. male, right wings and vein terminology; 7, Mecynostomella spinosa sp.n. male, scaloid seta from forewing Cu2, highly magnified; 8, Mecynostomella spinosa sp.n. female, right wings; 9, Mecynostomella brevis sp.n. male, right wings; 10, Mecynostomella hollowayi sp.n. male, right wings, a indicates the position of a pale area in the Cu­ and A­ area of the forewing, and made from minute structures shown in the next figure; 11, details of a single structure forming a pentagon and with a central opening, and which build up a pale area of the forewing as indicated in the previous figure; 12, Mecynostomella fusca Kimmins, 1953, right wings, with area covered by sensillae indicated by a surrounding black line; 13, Mecynostomella flinti sp.n., detail from wing membrane of dark area between forewing Cu and A, showing position of a modified sensilla and sensilla bases (t), dorsal view; 14, same species and sensilla, lateral view.