Stactobiella parallelica, Zhou, Lei, Yang, Lian-Fang & Morse, John C., 2016

Zhou, Lei, Yang, Lian-Fang & Morse, John C., 2016, New species of microcaddisflies from China (Trichoptera: Hydroptilidae), Zootaxa 4097 (2), pp. 203-219 : 211-213

Stactobiella parallelica n. sp.

( Fig. 5 )

Diagnosis. This new species from southeastern China is very similar to S. mutica n. sp., distributed in southwestern China, but S. parallelica n. sp. is readily distinguishable from S. mutica in that 1) the posteroventral hooks of pleura IX are very short, with tips tilted upward in lateral view and set far apart in ventral view (in S. mutica the hooks are slightly longer and straighter, with tips pointed backward in lateral view and very close to each other in ventral view); 2) the posterior 1/2 of the inferior appendages are straight, rod-like, and parallel to each other, each having a narrow apex in ventral view (in S. mutica the posterior portion of each inferior appendage is thumb-like, only 1/3 of the length of the appendage, with its apex obliquely truncate); and 3) the subgenital plate is less than 1/ 2 as long as the inferior appendages in ventral view (in S. mutica the plate is about 2/3 as long as the inferior appendages).

Male. Length of each forewing 1.5–1.7 mm (n=25). Antennae each 18-segmented (n=25). Ventral process on sternum VII small, short, triangular in lateral view.

Male genitalia. Anterior apodemes of segment IX projecting from middle of segment IX and extending forward to or slightly surpassing anterior margin of segment VII, posteroventral corners of pleura IX forming short hooks with acute tips tilted upward in lateral view ( Fig. 5 A), and strongly curved mesad with their tips set far apart in ventral view ( Fig. 5 C); posterior dorsum of segment IX forming subrectangular concavity ( Fig. 5 B). Tergum X membranous, subrectangular, with anterior margin about 1.3 times as broad as posterior margin and shallow emargination presented on posterior margin in dorsal view ( Fig. 5 A); in lateral view, apical portion of X broadly rounded, slightly exposed beyond posterior margins of segment IX. Inferior appendages partly exposed from beneath segment IX with their posterior ends extending beyond the hooked tips of segment IX in lateral view ( Fig. 5 A); in ventral view, anteroventral 1/2 of inferior appendages thick and straight-edged laterally, semicircular mesally, together outlining open oval, each with row of setae on inner surface of anterior end and with single pair of short setae submesally, posterior 1/2 of inferior appendages straight, rod-like, parallel to each other, with narrow apices pointed backward and each bearing two setae, one near base of rod and one at tip ( Fig. 5 C). Subgenital plate less 1/2 as long as inferior appendages in ventral view, anteriorly forming short stem covered with tiny setae, posterior half fan-like, with apical margin at most 3 times as broad as stem in ( Fig. 5 C). Aedeagus long, simple tube, broadest in basal 1/7, very slightly thicker near middle, apically almost straight ( Fig. 5 D).

Holotype. Male; CHINA. Jiang-xi Province, Jiu-Lian-shan Mt. National Nature Reserve, at the confluence of Huang-niu-shi & Da-shui-keng Streams, 1.2 km SE of Dun-tou Village, N24.31°, E114.25°, alt. 546 m, 9 June 2005, Coll. SUN C-h. Paratypes. Same data as holotype, 2 males; same Reserve except Dun-tou stream at San-dui bridge 500 m SE of Dun-tou village N24.32°, E114.25°, alt. 480 m, 9 June 2005, Coll. YANG L-f., and C. GERACI, 245 males; tributary of Da-qiu-tian River, Xia-gong-tang Stream, at Jiu-lian-shan Station hotel, N24°32’26”, E114°27’58”, alt. 590 m, 7 June 2005, Coll. YANG L-f. and C. GERACI, 19 males; Da-shui-keng Stream, 500 m upstream of confluence of Huang-niu-shi & Da-shui-keng Streams, N24.31°, E114.25°, alt. 553 m, 9 June 2005, Coll. ZHOU X., 1 male; at Da-qiu-tian Station, N24.34°, E114.25°, alt. 425 m, Coll. ZHOU X., 2 males; at Mei-hualuo-di of Da-qiu-tian Station, N24.35°, E114.27°, Coll. YANG L-f., 3 males.

Etymology. Greek, parallelica = being parallel, referring to the rod-like posterior portions of the inferior appendages that are parallel to each other.

Distribution. Oriental region of southeastern China: Jiang-xi.

Figures

FIGURE 5. Stactobiella parallelica n. sp. male genitalia. A, left lateral; B, dorsal; C, ventral; D, aedeagus. a. l. ap. = anterolateral apodeme of segment IX; inf. app. = inferior appendage; sub. g. pl. = subgenital plate; t. X = tergum X; IX = segment IX.