Orthotrichia discedata Zhou & Morse

Lei, Zhou, Lian-Fang, Yang & Morse, John C., 2010, Six new species and 1 new species record of Orthotrichia (Trichoptera: Hydroptilidae) from China, Zootaxa 2560, pp. 29-41 : 34-36

Orthotrichia discedata Zhou & Morse , sp. nov.

Figs 23–27

Material. Holotype ɗ, Fujian Province, Jiu-qu-xi (118°01'12"E, 27°27'00"N), elev. 220 m, 1990-v-30, Coll. J. C. Morse, Liu Chang-Ming, Huang Jian. Paratype: 21 3, same data as holotype.

Etymology. The Latin word “ discedata ” means “separated” or “divergent”, in reference to the right posterolateral process of tergum IX having 2 strongly divergent spines.

Description. Male. Antennae 23–24-segmented. Anterior wing length 1.6–1.7 mm. Ventral process of segment VI short spine in lateral view (as in Fig. 22 ). Ventral process of segment VII absent.

Male genitalia ( Figs 23–27 ). Anterior margin of segment IX irregularly curved, slightly narrowed anteriorly, anterior margin with shallow excision in dorsal view ( Fig. 25 ), bluntly convex in ventral view ( Fig. 26 ), widely excised in left lateral view ( Fig. 23 ), and with trapezoid excision in right lateral view ( Fig. 24 ); right posterolateral process of tergum IX having 2 strongly divergent spines, 1 branch directed upward and 1 turned to right; posterolateral margins of segment IX nearly straight, with postero-lateral processes absent ( Figs 23, 24 ). Tergite X (X) broad at base, with narrowed apex almost truncate ( Fig. 25 ), left pleural region of X strongly produced into a vertical ridge in left lateral view ( Fig. 23 ), forming ear-like process in dorsal view ( Fig. 25 ); right pleural region of X simple, its posterior margin slightly excised at center ( Fig. 24 ). Inferior appendages (inf. app.) asymmetrical, right inferior appendage deeply and broadly incised to short base in ventral view ( Fig. 26 ), its inner branch as long as tergum X, thick, tapered to acute upturned apex and bare, its outer branch 3/4ths as long as inner branch and with apical seta, left inferior appendage not incised, with a rounded basomesal shoulder, 2/3rds as long as inner branch of right inferior appendage, and bearing long, apical seta. Bilobed process (bil. pr.) forming 4 slender, widely curved, tube-like branches positioned above bases of inferior appendages, 2 branches on each side, each branch with apical seta. Paramere (pa., Fig. 25 ) single, stout, with apex hooked left, about as long as segment IX. Phallus ( Fig. 27 ) slender, basal portion about 2.5 times as long as distal portion, with its titillator encircling segment 1.5 times.

Diagnosis. This species is not assignable to any group. It is somewhat similar to Or. triacantha Mey, 2003 , from the Philippines, in the general shapes of the inferior appendages and segment IX, but differs in that 1) the right posterolateral process of tergum IX has 2 strongly divergent spines (without such a process in Or. triacantha ); 2) the left margin of tergum X is strongly produced into an ear-like process in dorsal view (with the left side straight in Or. triacantha ); and 3) the inner branch of the right inferior appendage is slightly longer than tergum X and much longer than either the outer branch of the appendage or the left inferior appendage (the inner branch of the right inferior appendage is much shorter than tergum X and subequal in length with the outer branch of the appendage in Or. triacantha ).

Distribution. Type locality only.

Figures

FIGURES 23 – 27. Orthotrichia discendata, sp. nov., male genitalia. 23, left lateral view; 24, right lateral view; 25, dorsal view; 26, ventral view; 27, phallus. Abbreviations explained in text.

FIGURES 17 – 22. Orthotrichia terpsichore Malicky & Chantaramongkol, 1997, male genitalia. 17, left lateral view; 18, right lateral view; 19, dorsal view; 20, ventral view; 21, phallus; 22, left lateral view of ventral process of segment VI. Abbreviations explained in text.