Siobla weni, Niu, Gengyun & Wei, Meicai, 2010

Niu, Gengyun & Wei, Meicai, 2010, Revision of the Siobla annulicornis, acutiscutella and sheni groups (Hymenoptera: Tenthredinidae), Zootaxa 2643, pp. 45-65 : 58-60

Siobla weni sp. nov.

(Plate 7)

Description. Holotype: Ψ.

Body length 13 mm. Body yellow brown with following black: 3rd and 4th antennomeres ventrally, 5 apical antennomeres entirely, middle of 5th abdominal tergite, 6th to 10th abdominal tergites entirely, a small round spot on posterior side of hind femur apically, apical 2/5 of hind tibia; middle of metabasitarsomere infuscate; clypeus, mouthparts, posterior part of mesoscutellum, appendage of mesoscutellum, each trochanter, basal 2/3 of hind tibia, and hind tarsomeres pale yellow. Body hairs yellow brown. Wings yellowish hyaline, apex of fore wing with a large smoky macula, inner margin of macula convex and reaching 1r-m, vein C and stigma yellow brown, other veins blackish brown (Figs. 7a, b).

Clypeus with sparse punctures, other parts of head densely punctured, without shiny interspaces, matt; pronotum rugose, tegula, propleuron and metapleuron except a middle stripe strongly shiny, without distinct punctures and microsculpture; mesoscutum densely punctured, feebly shiny; mesoscutellum with large punctures, interspaces narrow, matt; posterior slope of mesoscutellum densely punctured not shiny; appendage of mesoscutellum microsculptured; metascutellum densely punctured; elevated part of mesepisternum densely and coarsely punctured, anterior and posterior part sparsely punctured, shiny; venter of mesepisternum with sparse and shallow punctures, shiny; first abdominal tergite without microsculpture, shiny, other tergites indistinctly microsculptured, apical 5 tergites with shallow and sparse punctures.

Anterior margin of clypeus rounded, with small middle incision; malar space as long as diameter of ocellus; inner margin of eyes distinctly convergent downwards, shortest distance between eyes as long as eye height; middle fovea large and deep, merging with frontal basin; lateral fovea small; supra-antennal tubercles slightly elevated, narrow, connected to fine frontal ridge; interocellar furrow, postocellar furrow indistinct; lateral furrows deep, straight, parallel to each other posteriorly; postocellar area slightly elevated, slightly lower than top of ocelli, without middle carina, as long as broad; head behind eyes distinctly shorter than eye in dorsal view (14:19), lateral sides curved, distinctly convergent posteriorly; occipital carina sharp, complete (Fig.7e). Antenna slightly longer than abdomen, relative length of third to fifth antennomeres as 42:24:23, fifth to eighth antennomeres slightly dilated, compressed, inner and outer sides of each with a distinct furrow. Mesepisternum angularly elevated, with indistinct corner; mesoscutellum strongly elevated, much higher than top of scutum, apex feebly acute, anterior slope convex (Fig. 7h). Metabasitarsomere as long as following 4 tarsomeres together. Hairs on temple dense, slightly shorter than diameter of ocellus. Hairs on mesoscutellum sparse, much shorter than diameter of ocellus. Ovipositor longer than metabasitarsomere as 8: 7; sheath slender in lateral view (Fig. 7g). Lancet long and slender (Fig.7k), with 14–15 serrulae, middle serrulae each with 1 inner and 8–9 outer subbasal teeth (Fig.7l), apical 3 to 4 serrulae continuous.

PLATE 7. Siobla weni sp. nov. (a). Female adult in dorsal view; (b). Female adult in lateral view; (c). Male adult in dorsal view; (d). Male adult in lateral view; (e). Head of female in dorsal view; (f). Head of male in dorsal view; (g). Sheath in lateral view; (h). Mesonotum in lateral view; (i). Head of female in frontal view; (j). Head of male in frontal view; (k). Lancet; (l). Middle serrulae; (m). Penis valve; (n). Harpe and parapenis.

Male: Body length 11 mm (Figs.7c, d). Body yellow brown with face, lower part of inner orbit, frons, ocellar area, and lower part of hind orbit black; antenna black, scape, pedicel, and base and apex of 3rd antennomere reddish brown; anterior margin of pronotum, dorsum of scutum except a triangular middle spot (Fig.7f), mesopleuron, metapleuron, posterior part of metapostnotum, basal part of first abdominal tergite, lateral macula of 4th tergite, 5th to 8th tergites and 7th to 8th abdominal sternites black; legs yellow brown, most of coxae, base of fore femur dorsally, broad stripe on dorsum of middle and of hind femur, extreme base and apical 1/3 of hind tibia black, hind tarsus pale yellow. Wings indistinctly grayish hyaline, apical 1/3 distinctly infuscate, vein C and stigma yellow brown, other veins black. Body hairs pale brown. Punctation and structure similar to female except malar space hardly as long as radius of ocellus, shortest distance between eyes slightly narrower than eye height; head behind eyes as long as half of eye in dorsal view (Fig.7j); subgenital plate as long as wide, apex round; genitalia as in Figs. 5k, j.

Etymology: This species is named for the collector of the holotype.

Specimens examined: Holotype: Ψ, Mt. Badagong, Sangzhi, Hunan, alt. 1250m, 13 Aug, 2001, WEN Jun, HUANG Ning-Ting leg.; paratypes: 1ɗ, Mt. Huping, Shimen, Hunan, alt. 1500m, 19 July, 2002, WEI Mei-Cai leg.

Distribution: China (Hunan).

Remarks: The new species is similar to S. acutiserrula ., but differs from the latter by the following: body robust; clypeus roundly protruding and slightly incised medially; the peak of the mesoscutellum not very acute; the shortest distance between eyes as long as eye height in female; lancet with 15–16 serrulae, the middle serrulae each with 1 inner subbasal tooth and 8–9 outer subbasal teeth; most of head yellowish brown with face, lower part of inner orbit, frons, ocellar area, and lower part of hind orbit black, mesoscutellum yellowish brown include anterior part; lower parts of volsella and gonolacinia large.

PLATE 8. Siobla zhangi Wei, 2005 . (a). Female adult in dorsal view; (b). Female adult in lateral view; (c). Male adult in dorsal view; (d). Male adult in lateral view; (e). Head of female in dorsal view; (f). Head of male in dorsal view; (g). Mesonotum in lateral view; (h). Sheath in lateral view; (i). Lancet; (j). Apical serrulae; (k). Penis valve; (l). Harpe and parapenis.