Mecynostomella brevis, Johanson, 2003

Johanson, Kjell Arne, 2003, Revision of the New Caledonian genus Mecynostomella (Trichoptera, Kokiriidae), Zootaxa 270 (1), pp. 1-24 : 10-12

Mecynostomella brevis sp.n.

( Figs 9 , 23­27 , 54 )

Material examined: Male holotype: stream, Val de l'Hermitage, 1 km NE Terr. Route 1, 76 m, 10.x.1972 (N34) [W.L. & J.G. Peters] ( ROM, alcohol). 1 male paratype: Trib. of Karionan Riv., 5 km NW Païta, 122 m (N54), 14.xi.1972 [W.L. & J. G. Peters] ( NRM, alcohol) .

Etymology: brevis , from Latin, meaning short, referring to the lateral branch of the genitalia being smaller than that of Mecynostomella spinosa . To be treated as a noun in apposition.

Diagnosis: This species can be distinguished from hollowayi , sigma , flinti and fusca by the forewings with no area of modified sensillae; these sensillae are also lacking in caledonia and spinosa . Unique characters include a very shallowly incised posteroventral margin of the segment IX, a median branch located ventrally on the lateral branch, and a group of spines on the ventral margin of the phallic endotheca.

Male.

Colors faded. Antennal flagellum with 38 flagellomeres.

Thorax: Pronotum with setae confined to large warts.

Wings ( Fig. 9 ): Forewing length 9.6 mm (N=1), greyish­black, hind wing 8.4 mm (n=1), grey. Venation as described for genus.

Genitalia ( Figs 23­27 ): Segment IX, lateral view ( Fig. 23 ), about 2.3x higher than long; anterior margin shallowly ellipsoidal, dorsally pointed; ventral margin shallowly and widely incised posteriorly ( Fig. 25 ). Segment X with simple central branch almost parallel­sided at distal half in dorsal view ( Fig. 24 ); in lateral view ( Fig. 23 ), almost parallelsided along proximal half and strongly tapered distally; dorsal margin bent ventrally at mid­length; with few setae on distal half; nearly 2x longer than high ( Fig. 23 ); apex narrowly rounded in lateral view, slightly incised in dorsal view ( Fig. 24 ); lateral branch nearly as long as central branch; tubular, sub­straight in lateral ( Fig. 23 ) and dorsal ( Fig. 24 ) views; short setae confined to apex and ventral sub­apical margin; median branch, lateral view ( Fig. 23 ), large, semicircular, about as long as lateral branch; in dorsal view ( Fig. 24 ), oriented posteriorly, visible between central and lateral branches, pointed. Gonocoxite, lateral view ( Fig. 23 ), generally curving dorsally along its length; dorsal margin concave, ventral margin sub­straight, apex produced dorsally; slender sub­apical part about 0.8x as high as proximal part; in ventral view ( Fig. 25 ) oriented posteriad along its length; covered by setae along its length but most numerous at apex. Phallus simple; phallobase, lateral view ( Fig. 26 ), length about three­quarts the height of segment IX; endotheca produced dorsally from distal half on dorsal side, with small spines on ventral margin; in ventral view ( Fig. 27 ), lateral incisions at proximal part located posteriorly of anterior margin of phallus opening.

Female: unknown.

Figures

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.

FIGURES 23­27. Mecynostomella brevis sp.n., male holotype. 23, genitalia, lateral view; 24, genitalia, dorsal view; 25, genitalia, ventral view; 26, phallus, lateral view; 27, 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).