Bittacus multisetus, Hua, 2022

Le-Le, HE & Bao-Zhen, HUA, 2022, A review of Bittacidae (Mecoptera) in Guizhou, China with descriptions of three new species, European Journal of Taxonomy 839, pp. 103-119 : 114-117

Bittacus multisetus sp. nov.

urn:lsid:zoobank.org:act:C5F64A5A-1EF3-4CB2-B5A4-5763792CD230

Figs 8–10

Diagnosis

The new species can be distinguished from its congeners by the following features: 1) few markings on wings ( Fig. 9 ); 2) the epandrial appendages greatly elongated, subrectangular in lateral aspect ( Fig. 10A ); 3) the upper branch of the proctiger elongated, expanded distally, bent anteriorly, bearing an apical hair bundle ( Fig. 10A ); and 4) numerous long setae along the lateral sides of the female subgenital plates ( Fig. 10F ).

Etymology

The specific epithet ʻ multisetus ʼ is derived from the Latin ʻ mult -ʼ (many) and ʻ set -ʼ (bristle), referring to the numerous setae along the lateral margins of the female subgenital plates.

Type material

Holotype CHINA • ♂; Guizhou Province, Shuicheng County, Yushe National Forest Park; 26°27′36″ N, 104°48′36″ E; 1900–2200 m a.s.l.; 4–6 Jul. 2012; Jing Chen and Ying Miao leg.; NWAU.

Paratypes CHINA • 2 ♀♀; Guizhou Province, Shuicheng County, Yushe National Forest Park; 26°27′36″ N, 104°48′36″ E; 2100–2200 m a.s.l.; 10 Jul. 2021; Le-Le He leg.; NWAU .

Description

MEASUREMENTS. AL 5.2–6.8 mm, BL 13.1–15.2 mm, FL 17.4–18.3 mm, FW 4.5–5.7 mm, HL 15.4– 16.9 mm, HW 3.3–4.2 mm.

HEAD ( Fig. 8B ). Vertex blackish brown; frons yellowish brown; median ocellus similar to lateral ocelli; black transverse band passing through ocellar triangle to compound eyes; clypeus and labrum blackish brown; maxillary palps unevenly colored, most segments black except distal segment yellowish brown; 3 rd segment slightly longer than 4 th and 5 th segments combined. Antennae yellowish brown, filiform.

THORAX ( Fig. 8C ). Pronotum blackish brown, without setae along anterior or posterior margins; mesonotum dark brown except scutum and median part light brown, two long setae along posterior margin; metanotum brown to light brown. Pleura unevenly yellowish brown. Legs yellowish brown, with femora and tibiae darker apically; two tibial spurs long ( Fig. 8D ); hind basitarsus as long as tarsomeres II−IV together, one black spine along each side of proximal tarsomere IV ( Fig. 8E ).

WINGS ( Fig. 9 ). Forewing membrane hyaline with light brown tinge, apex faintly subacute; pterostigma brown; three small grayish brown clouding speckles on OM, ORs, and FRs respectively; remaining cross-veins with diffuse light grayish brown cloudings; sparse short spinules along outer margin. Pcv two. Sc ending slightly beyond level of FRs; Scv before FRs; Cuv near level of FM; CuP near FM 3+4; Cuv two; 1A ending far before FM; 2A ending before OM; Av absent. Hindwing similar to forewing, but Sc ending before FRs, Pcv one.

ABDOMEN OF MALE ( Fig. 10A–C ). Terga II–IV yellowish to light brown; terga V–VIII blackish brown; tergum VIII slightly emarginate on posterior margin; each with a dark antecosta. Epandrial appendage pale brown, approximately twice as long as gonocoxite, subrectangular with caudal margin rounded, two or three rows of black spines on inner surface along dorsal and apical margins, bearing a cluster of long black subapical setae on ventral margin. Tergum X greatly vestigial. Upper branch of proctiger yellowish brown, expanded distally, bent anteriorly, with apical hair bundle; lower branch of proctiger shorter, tapering toward apex. Cerci yellowish brown, clavate, longer than half length of gonocoxites. Gonocoxites blackish brown, shortened; distal portion protruding into subtriangular lobes separated by a deep V-shaped membranous median area; gonostylus with a process on inner side, and surrounded by sparse black setae. Aedeagus with paired elongated lobes; penisfilum coiled.

ABDOMEN OF FEMALE ( Fig. 10D–F ). Terga II–IV yellowish to light brown; terga V–X blackish brown; a black antecosta on each tergum. Subgenital plate dull yellowish brown, greatly sclerotized; subgenital plate connected basally with lateral margin of tergum VIII, and curved dorsally for distal portion in lateral view; proximal two-thirds of plates prominently separated by V-shaped membrane, with a row of black setae along distal margin; approximately seven long black setae at median and lateral edge of each subgenital plate. Tergum X extending to base of cerci. Supra- and subanal plate acute caudally, bearing dense yellow hairs. Cerci yellowish brown, tapering toward apex, longer than supraanal plate.

Distribution

Guizhou Province, China.

Remarks

The new species is similar to B. puripennis Cai & Hua, 2006 from Shaanxi Province, but can be differentiated from the latter by the following characters: no prominent meso- and metanotum median streak (cf. the median meso- and metanotum streak pale); the distal margins of the epandrial appendages rounded (cf. the distal margins of the epandrial appendages acute); and the upper branch of the proctiger expanded distally, bent anteriorly (cf. the upper branch of the proctiger finger-like, straight).

Figures

Fig. 8. Bittacus multisetus sp. nov., ♀, paratype (NWAU). A. Habitus in lateral view. B. Head in frontal view. C. Thorax in dorsal view. D. Tibia with two apical tibial spurs of left foreleg. E. Tarsomeres IV, V and claw of left foreleg. Abbreviations: see Material and methods. Scale bars: A = 5.0 mm; B = 0.2 mm; C–D = 0.5 mm; E = 0.1 mm.

Fig. 9. Right wings of Bittacus multisetus sp. nov., ♀, paratype (NWAU). Abbreviations: see Material and methods. Scale bar = 2.0 mm.

Fig. 10. Bittacus multisetus sp. nov.A–C. ♂, holotype (NWAU). A. Terminalia in lateral view.B. Terminalia in dorsal view. C. Terminalia in posterior view.D–E. ♀, paratype (NWAU). D. Terminalia in lateral view. E. Terminalia in dorsal view. F. Terminalia in ventral view. Abbreviations: see Material and methods. Scale bars = 0.2 mm.