Chimarra obscurella Banks

Johanson, Kjell Arne & Oláh, János, 2012, Revision of the Fijian Chimarra (Trichoptera, Philopotamidae) with description of 24 new species, Zootaxa 3354, pp. 1-58 : 55-56

Chimarra obscurella Banks

Figs. 34 , 170–174

Chimarrha obscurella Banks, 1924: 449 .

The genitalia of C. obscurella somewhat resemble those of C. tokotaai , particularly in the shape of the gonopods in lateral view. It is distinguished from C. tokotaai by the more stepwise narrowing of tergum X in lateral view and broader tergum X in dorsal view; by the presence of 2 large endothecal spines; and the ventral, transverse apodeme of segment IX is located nearer the mid-length of the segment.

Male. Body brown, dorsal part of meso- and metathorax brown. Large dark area between lateral and anterior ocelli. Foreleg anterior claw as long as foreleg spur.

Wings ( Fig. 34 ). Forewings 4.6 mm (holotype), brown; R1 nearly straight before crossvein r; radial sector strongly produced anterad immediately before discoidal cell; discoidal cell originating at mid-length of wing, about 3x longer than wide; median cell as long as discoidal cell; crossvein r situated as basis of fork I; fork I originating before crossvein s at distance equal to 1.2x length of crossvein s; nygma located near base of fork II; fork III 1 /5th as long as wing; fork V as long as fork I, shorter than fork II; Cu2 separate from A at wing margin. Hind wings 3.6 mm (holotype), brownish; margin nearly straight at where Cu1 and Cu2 fused with margin; fork III as long as discoidal cell and 1/8th as long as wing; fork V as long as fork I.

Male genitalia ( Figs 170–174 ). Segment IX slightly shorter than high; ventral part of segment produced into hyperbolic lateral plates in lateral view; dorsal part of segment not produced anterad; each anterodorsal margin shallowly and widely concave in lateral view; each ventral margin convex, incised at anterior 1/3rd at vertical apodeme; each posterior margin forming irregular plate pointing posterad at ventral corner; originating immediately below cercus; posterior third of ventrum IX with setae ( Fig. 172 ). In dorsal view anterodorsal margin forming wide, shallow, U-shaped incision without processes. In ventral view segment IX with undulating lateral margins, incised at transverse apodeme; with concave anterior margin and nearly straight posterior margin; posterior margin without central projection. Tergum X simple; forming pair of lateral branches from basis of segment, immediately posteriorly of cerci; lateral branches nearly straight, directed posteroventrad in lateral view; basal 1/3rd broad in lateral view, sharply narrowing before mid-length; in dorsal view forming very broad, posterad directed, nearly parallel plates, slightly narrowing mesally at mid-length into trapezoid distal 1/2; each lateral process with apex located mesally. Cerci short, cylindrical, situated on posterior margin of segment IX at mid-height of basis of tergum X in lateral view and oriented posterad in lateral view; covered by long setae. Gonopods nearly as long as segment IX, nearly triangular in lateral view, with very large tapering dorsal branch, and minute, triangular ventral branch. Dorsal branch of each gonopod produced dorsad, not posteriorly exceeding tergum X in lateral view; anterodorsal and posterior margins slightly convex before apex, ventral margin convex; in dorsal view dorsal branches curved and pointed mesad above tergum X; without megasetae. Ventral branch of each gonopod short triangular in ventral view; orienting posteromesad, with irregular mesal margins; megasetae absent. Mesal branches formed by produces setal bases, located basally on gonopods. Phallic apparatus about 1.5x longer than rest of genitalia; nearly straight along its length: phallotheca, in lateral and ventral view, with anterior part slightly thicker than posterior part; apicoventral spine absent on phallotheca; phallotremal sclerite not observed; 2 long, thick, nearly black endothecal spines present.

Female. Unknown.

Holotype male: “Fijis: Taviuni, Somo Somo. W. M. Mann ”; “M.C.Z. Type 14824”; “ Chimarrha obscurella type Bks”. Abdomen macerated, in glycerol in micro vial on same pin as rest of animal [ MCZ].

Distribution: Taveuni.

Figures

FIGURES 32 – 34. Type specimens of Chimarra described by Banks. 32 — C. signata Banks, 1936, holotype; 33 — C. manni Banks, 1924, lectotype; 34 — C. obscurella Banks, 1924, holotype.

FIGURES 170 – 174. Chimarra obscurella Banks, 1924, holotype. 170 — genitalia, left lateral view; 171 — genitalia, dorsal view; 172 — genitalia, ventral view; 173 — phallic apparatus, left lateral view; 174 — phallic apparatus, ventral view.