Terrobittacus laoshanicus, He & Hua, 2023

He, Le-Le & Hua, Bao-Zhen, 2023, Two new species of the genus Terrobittacus Tan & Hua, 2009 (Mecoptera, Bittacidae), ZooKeys 1148, pp. 29-39 : 29

Terrobittacus laoshanicus sp. nov.

Figs 3 , 4 , 5

Type material.

Holotype: ♂; China, Guangxi Province: Tianlin County, Laoshan Forest Farm; 24°23'51"N, 106°23'9"E; alt. 1270 m; 24-29 June 2022; leg. Le-Le He and Ya-Long Li (NWAU). Paratypes: 3♂7♀, same data as for the holotype.

Diagnosis.

This new species is distinguishable from its congeners by the basal half of mesonotum unevenly blackish brown, distal half yellowish brown; terga II-V yellowish brown, terga VI-IX black; the epandrial appendage triangular, with a tooth on basal ventral margin; the gonostylus with a process on inner side; female subgenital plate almost completely fused.

Description.

Measurements (N = 11): AL = 4.77 ± 0.42 mm; BL = 11.19 ± 1.28 mm; FL = 14.51 ± 0.56 mm, FW = 3.51 ± 0.11 mm; HL = 12.44 ± 0.38 mm, HW = 3.05 ± 0.21 mm.

Head (Fig. 3C ) Vertex and frons yellowish brown; ocellar triangle black, dark ocellar strip extending to compound eyes; clypeus yellowish brown; labrum unevenly blackish brown; maxillary palp yellowish brown, 3rd segment equal to 4th and 5th segments combined. Antennae yellowish brown; scape and pedicel spherical; flagellum filiform and ciliated, with distinct segments basally and obscure beyond 10th segment.

Thorax (Fig. 3D ) Pronotum blackish brown; anterior half of mesonotum unevenly blackish brown, posterior half mesonotum and metanotum yellowish brown. Pleura, coxae and mera light brown (Fig. 5A ). Legs yellowish to reddish brown; femora and tibiae with distinct blackish brown apices; length of two apical tibial spurs almost equal (Fig. 3E ); hind basitarsus as long as tarsomeres II-IV together; tarsomere IV with two black spines along each side (Fig. 3F ).

Wings (Fig. 3A ) Forewing membrane hyaline with yellowish brown tinge; pterostigma reddish brown; four conspicuous markings each at ORs, FRs, CuP ending, and R5 ending; remaining cross-veins with diffuse clouding flecks; Pcv one. FRs near level of FM; Sc ending distantly before level of FR4+5; Scv near FRs; CuP ending curved posteriorly, and near FM3+4; Cuv before level of FM; 1A ending before FM; 2A ending before OM; Av absent. Hindwing similar to forewing in general pattern and coloration, but Sc ending before level of FRs.

Abdomen of male (Fig. 4D-H ) Terga II-V yellowish brown, each with a black antecosta; terga VI-IX black (Fig. 3B ). Tergum VIII emarginate on posterior margin. Epandrial appendage triangular, prominently shorter than half length of gonocoxites; distal inner surface bearing a cluster of more than 50 black spines (Fig. 4G ), with a tooth on basal ventral margin. Tergum X greatly vestigial, narrow brown lateral plate extending to base of cercus. Upper branch of proctiger yellowish brown, long and straight, with hairy apex; lower branch of proctiger short, tapering toward apex, curved ventrad (Fig. 4H ). Cerci yellowish brown, considerably short, about one-quarter length of gonocoxites, acute apically. Gonocoxites blackish brown and rounded, distal membranous area furnished with numerous long yellow hairs. Gonostylus short, with process on inner side, and surrounded by sparse brown setae. Aedeagal lobes broad basally, with two small acute apexes; penisfilum coiled into loops.

Abdomen of female (Fig. 4A-C ) Abdomen similar to that of male in coloration. Subgenital plate sclerotized, blackish brown, two halves almost completely fused, several brown setae along distal portion. Tergum X narrow, not extending ventrad. Supra- and subanal plates yellowish brown, broad; almost equal length. Cerci yellowish brown, tapering toward apex, longer than anal plates.

Etymology.

The specific epithet refers to the type locality, Laoshan Forest Farm.

Distribution.

China (Guangxi Province).

Remarks.

The new species resembles T. echinatus (Hua & Huang, 2008) in wing coloration and pattern, but can be readily differentiated from the latter by the following traits: terga II-V yellowish brown, terga VI-IX black (cf. terga II-IX yellowish brown); female subgenital plate almost completely fused (cf. cleft by membrane); epandrial appendages triangular (cf. roughly trapezoid).

Figures

Figure 3. Terrobittacus laoshanicus sp. nov. A right wings of male B female body in dorsal view C head in frontal view D thorax in dorsal view E tibia with two apical tibial spurs of left foreleg F tarsomeres IV, V and claw of left foreleg. Abbreviations: see Materials and methods. Scale bars: 2.0 mm (A, B); 0.5 mm (C, D); 0.2 mm (E, F).

Figure 4. Terrobittacus laoshanicus sp. nov. A female terminalia in lateral view B female terminalia in dorsal view C female terminalia in ventral view D male terminalia in lateral view E male terminalia in dorsal view F male terminalia in posterior view G epandrial appendages in ventral view H abdominal segment X and proctiger in lateral view. Abbreviations: see Materials and methods. Scale bars: 0.5 mm (A-C, E); 0.2 mm (D, F-H).

Figure 5. Terrobittacus laoshanicus sp. nov. A male habitus in lateral view B habitat. Scale bar: 5.0 mm (A).