Hygiella luteipes

Hiroshi Shima & Takuji Tachi, 2016, New species of Hygiella Mesnil (Diptera: Tachinidae), parasitoids of leaf insects (Phasmatodea: Phylliidae), Journal of Natural History 50 (25), pp. 1648-1668 : 1657-1658

Hygiella luteipes sp. nov.

( Figure 2 A, B)

Description

Female. Head broadly yellow/brown in ground colour, darkened on fronto-orbital plate, postorbit and upper occiput, with dense white pruinosity, somewhat grey on fronto-orbital plate; frontal vitta pale brown; antenna orange yellow on scape, pedicel and basal half and inner portion of first flagellomere, outer apical half of first flagellomere and arista brown/black; prementum, labella and palpus yellow. Vertex about onequarter of head width; frontal vitta widened anteriorly, slightly narrower than frontoorbital plate at middle; parafacial weakly narrowed below, about three-fifths (about onethird in profile) as wide as first flagellomere at middle height; gena 0.26 (about twoninths in profile) of eye height, genal dilation occupying only lower and posterior third of gena. Inner vertical seta very long, about four-fifths of eye height; outer vertical seta absent; ocellar seta fine hair-like, nearly as long as postocellar seta; one reclinate orbital seta, half as long as inner vertical seta; two subequally long proclinate orbital setae twothirds as long as inner vertical seta; six or seven frontal setae, lowest seta nearly level with base of pedicel; fronto-orbital plate almost lacking hairs, at most with one or two very fine short hairs among row of frontal setae; facial ridge with a few short setae on lower quarter; two subvibrissal setae; gena with only a few fine hairs and one strong seta on genal dilation; occiput without black hairs except on lower one-fifth. Antenna falling short of lower margin of face by about length of pedicel; pedicel with many short hairs and a long strong seta which is about twice as long as pedicel; first flagellomere about 3.5 times as long as pedicel; arista short pubescent on basal third and almost bare apically, about 1.2 times as long as antenna, thickened on basal third, second aristomere shorter than wide. Palpus weakly clavate, about as long as first flagellomere.

Thorax dark brown in ground colour, scutellum red/yellow on apical half, with rather dense grey/white pruinosity; scutum with two narrow inner and two broad outer longitudinal vittae, inner vittae merged each other and outer vittae diffusing marginally on postsutural area; pleura with thin grey pruinosity. Two or three presutural and three postsutural acrostichal setae; three presutural and three postsutural dorsocentral setae; three katepisternal setae, lowest seta shorter than upper setae; anatergite bare; scutellum with three pairs of marginal setae, lateral seta indistinct, basal seta about five-sixths as long as subapical seta and about twice as long as scutellum, apical setae almost 1.5 times as long as scutellum; distance between bases of subapical setae slightly more than 1.5 times that between basal and subapical setae of corresponding side.

Wing hyaline, evenly and weakly tinged with pale brown; tegula black, basicosta pale red/yellow; lower calypter translucent pale brown/yellow. Costal spine distinct, about twice as long as costal setae; second costal sector haired below; basal node of vein R4+5 with three fine hairs dorsally and one ventrally. Relative lengths of costal sectors second, third and fourth approximately as 1: 4: 1.5; vein M from dm-cu crossvein to its bend about 1.8 times distance between the bend and wing margin.

Legs red/yellow, tarsi pale brown; pulvilli pale yellow. Fore tibia with two posterior setae; mid tibia with two anterodorsal setae; hind tibia with a row of sparsely set anterodorsal setae, a submedian seta strong, four posterodorsal and two or three ventral setae. Fifth tarsomere of fore leg elongate and flattened, more than twice as long as fourth tarsomere; claws and pulvilli about half as long as fifth tarsomere.

Abdomen black in ground colour, rather densely covered with grey pruinosity, the pruinosity thinner on posterior portion of third and fourth tergites, posterolateral portion of fifth tergite appearing black, mid dorsal longitudinal vitta distinct on third and fourth tergites. Hairs on dorsum dense and fine, rather short and recumbent; syntergite 1 + 2 with a pair of strong median marginal setae, which are slightly longer than third tergite, and a pair of strong lateral marginal setae; third tergite with a pair of strong median marginal and lateral marginal setae; fourth and fifth tergites with a row of marginal setae.

Female terminalia: sixth sternite with dense, short, and strong spinules on posteromedian portion; seventh sternite strongly curved anteroventrally and pointed at apex, with a mid ventral groove; eighth sternite narrow and curved anteriorly, embedded in mid ventral groove of seventh sternite.

Male. Unknown.

Body length: 5.8 mm.

Holotype female, Wolong, 1200 m, Wenjiang Xian, Sichuan, China, 11.viii.1993, H. Shima ( IZCAS).

Etymology

This species is named for its yellow legs, from the Latin luteus, meaning yellow, plus the Latin pes, meaning foot.

Remarks

This species is characteristic in having yellow legs and basicosta and three postsutural dorsocentral setae. Although the male of this species is unknown, this species is distinct and is easily distinguished from the other species of Hygiella .

Figures

Figure 2. Habitus (A, C) and head in lateral view (B, D). (A, B) Hygiella luteipes sp. nov., female. (C, D) Hygiella nigripes Mesnil male. Scales: 1 mm.