Simulium (Montisimulium) luliangense Chen and Lian

Han-Bin, Chen, Guo-Sheng, Lian & Chun-Lin, Zhang, 2011, A faunal summary of Simulium (Montisimulium) with descriptions of five new species from China (Diptera: Simuliidae), Zootaxa 3017, pp. 51-68 : 60-62

Simulium (Montisimulium) luliangense Chen and Lian , sp. nov.

( Figs. 32–43 )

Female. Body length about 3.8 mm. Wing length about 3.4 mm.

Head. Narrower than thorax. Frons and clypeus dark brown, grey-dusted. Frontal ratio 7:1:4.4:8.5; frons-head ratio 7.1:31.8. Antenna composed of 2+9 segments, brown except scape and pedicel pale. Maxillary palp with 5 segments, proportional lengths of 3rd to 5th segments 6.8:6.1:15.2; 3rd segment enlarged, with oblong sensory vesicle, which is about 0.6 length of respective segment. Maxilla with 9 inner teeth and 16 outer ones. Mandible with 27 inner teeth and lacking outer ones. Cibarium without denticles.

Thorax. Scutum brownish black, covered uniformly with golden pubescence as well as sparse black hairs on prescutellar area. Scutellum brownish grey, with sparse golden pubescence and some black hairs. Postscutellum dark and bare. Pleural membrane and katepisternum bare. Legs and wing nearly as in S. (M.) schizostylum sp. nov.

Abdomen. Basal scale pale brown with a fringe of brown hairs. Terga brownish black except 2nd tergum pale brown. Genitalia. Sternite 8 with a lot of black hairs on each side. Anterior gonapophyses triangular in shape, covered with several microsetae; inner margin lightly sclerotized. Genital fork with sclerotized slender stem; each arm with sclerotized posterolateral ridge but devoid of projection directed forwards. Spermatheca ellipsoidal and with reticulate pattern. Paraproct and cercus of moderate size.

Male. Body length about 4.0 mm. Wing length about 3.6 mm.

Head. Width equal to that of thorax. Upper-eye consisting of 18 vertical and 19 horizontal rows of large facets. Clypeus brownish black with brown hairs. Antenna brown, 1st flagellomere about 2.2 times as long as following one. Maxillary palp with 5 segments, sensory vesicle almost rounded which is about 0.22 length of 3rd segment.

Thorax. Nearly as in S. (M.) schizostylum . sp. nov.

Abdomen. Basal scale brown, with fringe of brownish yellow hairs. Terga dark brown with brownish black hairs. Genitalia: Gonocoxite subconical in shape, about 1.3 length of width in ventral view. Gonostylus small, about 0.7 length of gonocoxite, abruptly narrowed apically but without bifid tip; when viewed vetrolaterally, gonostylus with outwardly directed subapical rounded projection which has several small stout teeth. Ventral plate subrectangular in ventral view, with distal margin concave and posterolateral corner pointed apically; proximal median margin distinctly produced forward, each lateral margin having outwardly directed scletorized basal process; ventral and posterior surfaces with setae medially; basal arms about 2/3 length of plate body and converging apically. Parameres each with 8 or 9 strong parameral teeth. Median sclerite long.

Pupa. Body length about 4.3 mm.

Head and thorax. Nearly as in S. (M.) xinzhouense sp. nov. and S. (M.) schizostylum sp. nov. except the secondary stalk of the upper pair of filaments is very short.

Abdomen. Arrangement of setae, spines and hairs of dorsal and ventral surfaces of abdomen similar to those of S. (M.) xinzhouense sp. nov. and S. (M.) schizostylum sp. nov. Cocoon: Wall-pocket-shaped, tightly woven, extending ventrolaterally, with strong anterior margin and a small anterodorsal projection.

Mature larva. Body length about 7.0 mm. Cephalic apotome with faint head spots. Antenna composed of 3 segments and a terminal sensory organ; proportional lengths of 3 segment from base to tip of 6.9:7.8:4.0. Labral fan with 32–34 main rays. Mandible with a large and a small mandibular tooth but lacking supernumerary serrations. Hypostomium with 9 pointed apical teeth; corner and median teeth prominent and intermediate ones smallest; lateral serrations weakly developed; 7 or 8 hypostomal setae on each side lying subparallel to lateral margins. Postgenal cleft minute. Thoracic and abdominal integument bare. Rectal gills compound, each of 3 lobes with 7 or 8 finger-like secondary lobules. Anal sclerite with complete posterior arms to which anterior arms unite individually. Ventral papillae well developed.

Type materials. Holotype Ƥ, reared from pupa. Slide-mounted with pupal exuviae and cocoon. Collected in a rivulet by Lian Guo-Sheng from a stone (37°88ʹN, 111°24ʹE, 2000m). Paratype. 3Ƥ, 233, 17 pupae and 4 larvae, same data as holotype.

Distribution. Shanxi Province. China.

Remarks. This new species is related to S. (M.) schizostylum sp. nov. from China in some aspects including the female genitalia and the pupal filament branching pattern, but the new species is quite different in the shape of the male gonostylus, ventral plate and median sclerite, the very short secondary stalk of the uppermost pair of pupal filaments and some characters of larva.

Etymology. The specific name was given for its type locality.

Figures

FIGURES 32 – 43 S. (M.) luliangense Chen and Lian, sp. nov. 32. Female genitalia; 33. Female cibarium; 34. Female sensory vesicle; 35. Gonocoxite and gonostylus of male; 36. Ventral plate; 37. Median sclerite; 38. Paramere; 39. Cocoon in dorsal view; 40. Filaments; 41. Larval head capsule in ventral view; 42. Larval mandible; 43. Larval anal sclerite.