Siobla weiweii Niu & Wei

Niu, Gengyun & Wei, Meicai, 2013, Revision of the Siobla formosana group (Hymenoptera: Tenthredinidae), Zootaxa 3746 (1), pp. 41-68 : 54-55

Siobla weiweii Niu & Wei , sp. nov.

( Figs 6 a, 6b, 6c, 6d, 9b, 9o)

Description. Holotype: ♀. Length, 12 mm ( Figs 6 a, 6b). Black, labrum blackish brown, palpi dirty brown, entire 2nd to 4th abdominal tergites and middle of 10th tergite, 2nd to 5th sternites, middle longitudinal stripe on 7th sternites, and cerci pale brown; antenna yellowish brown, most of 1st and of 2nd antennomeres and base of 3rd antennomere black, 8th and 9th antennomeres blackish brown; legs yellowish brown, fore and middle coxae, most of hind coxa, basal margin of fore femur, basal 0.2 of middle femur, and apical 5/6 of hind femur black, spot on venter of apex of hind tibia dark brown; body hairs silver; wings hyaline, pterostigma brown except extreme base pale brown.

Head densely punctured, punctures on labrum fine and sparse; prescutum, scutum and anterior slope of mesoscutellum densely punctured, interspaces narrow; punctures on lateral parts of mesoscutellum obvious and sparse, interspaces shiny; posterior slope of mesoscutellum densely punctured, without interspace; posttergite and metapostnotum shiny with margins slightly microsculptured; mesoparapsides with large and sparse punctures and dense microsculpture; metascutellum with anterior slope shiny and posterior slop densely punctured; metapostnotum shiny with margins slightly microsculptured; middle and upper of mesepisternum densely and coarsely punctured, venter with large and shiny interspaces between small and sparse punctures; anepimeron coarsely punctured, katepimeron microsculptured, posterior shiny; metepisternum with upper densely punctured, interspaces narrow, feebly shiny, and venter sparsely punctured, shiny; basin of metepimeron shiny, dorsum of metepimeron with large punctures, posterior corner shiny. First abdominal tergite shiny with very weak microsculpture, lateral edges hardly punctured; other tergites weakly microsculptured, lateral edges of 4th tergite and entire of 5th to 8th tergites punctured.

Hairs on dorsum of head straight, 1.2 × as long as diameter of lateral ocellus. Middle of clypeus with transverse carina, anterior margin truncate; malar space 0.9 × as long as transverse diameter of median ocellus; shortest distance between eyes below antennal sockets in front view as long as eye height; middle fovea broad and shallow; interocellar furrow narrow and deep, postocellar furrow narrow and shallow; postocellar area 1.3 × as broad as long, obviously lower than top of ocelli, middle obviously elevated; lateral furrows deep, nearly straight, divergent posteriorly; head behind eyes 0.8 × length of eye in dorsal view; curved laterally and then convergent posteriorly; genal carina sharp, complete ( Fig.6 c). Antenna as long as head, thorax, and 1st abdominal tergite together, slightly shorter than vein C, 2nd antennomere 1.4 × as long as broad, relative length of 3rd to 4th antennomeres as 1.8, 5th to 8th antennomeres weakly compressed, not enlarged, inner and outer sides of 6th to 8th antennomeres with weak furrows, 7th antennomere about 1.9 × as long as broad. Middle furrow of prescutum deep; mesoscutellum elevated with a peak, higher than scutum ( Fig. 6 d). Metabasitarsus 4.7 × as long as broad, about 1.2 × length of following 3 tarsomeres combined, hind inner tibial spur 0.4 × length of metabasitarsus. Pulvilli of hind tarsus weakly developed, 1st pulvillus 0.7 × basal breadth and 0.4 × apical breadth of metabasitarsus, distance between basal two pulvilli 4 × length of 2nd pulvillus. Ovipositor sheath 1.2 × length of middle tibia, venter margin curved, exposed part of apical sheath slightly narrower than apex of hind tibia, about 1.6 × as long as broad; apical sheath 1.5 × length of basal sheath. Lancet with 17 serrulae ( Fig. 9 b), middle serrulae each with 4 distal fine teeth ( Fig. 9 o).

Male. Unknown.

Etymology: This species is named after the first name of the collector of the holotype.

Specimens examined. Chongqing: Holotype: 1♀, Dafengbao, Huangshui, Shizhu, Chongqing, 2006-V-3, Zhang Weiwei leg.; CSCSHT 0 0 810026 (CSCS).

Distribution. China (Chongqing).

Remarks. The new species is similar to S. acutitheca Niu & Wei, 2010 , but differs from it in tegula and pronotum entirely black; the pterostigma black brown; the base of fore and middle femora with black spot; the dorsal side of the apex of lancet acute; serrulae weakly protruding, the 10th serrulae with 4 distal teeth; and the first pulvillus of hind tarsus very small.

Figures

FIGURE 6. Siobla species, a – d. S. weiweii, sp. nov., holotype, ♀; a. Adult, dorsal view; b. Adult, lateral view; c. Head, dorsal view; d. Mesoscutellum, lateral view; e – i. S. acutitheca, e. Abdominal tergites; f. Head, ♀, dorsal view; g. Head, ♂, dorsal view; h. Mesoscutum and mesoscutellum, ♀; i. Sheath, lateral view; j – n. S. pseudoplesia, j. Abdominal tergites; k. Head, ♀, dorsal view; l. Head, ♂, dorsal view; m. Mesoscutum and mesoscutellum, ♀; n. Sheath, lateral view. Scale bar = 1 mm.

FIGURE 9. Siobla species, lancet. a. S. acutitheca; b. S. weiweii, sp. nov., c. S. atra, d. S. rufopropodea, e. S. carinoclypea, f. S. listoni, g. S. parallela, sp. nov., h. S. pseudoplesia, i. S. semipicta, j. S. zuoae, k. S. formosana, l. S. fumipennis, m. S. jiangi, sp. nov.. Middle serrulae. n. S. acutitheca; o. S. weiweii, sp. nov., p. S. atra, q. S. rufopropodea, r. S. carinoclypea, s. S. listoni, t. S. parallela, sp. nov., u. S. pseudoplesia, v. S. semipicta, w. S. zuoae, x. S. formosana, y. S. fumipennis, z. S. jiangi, sp. nov .. Scale bar = 100 Μm.