Terrobittacus rostratus, Hua, 2017

Du, Wei & Hua, Bao-Zhen, 2017, Two new species of the genus Terrobittacus Tan & Hua, 2009 (Mecoptera: Bittacidae) from southwestern China with a key to species, European Journal of Taxonomy 294, pp. 1-13 : 3-7

publication ID	https://doi.org/ 10.5852/ejt.2017.294
DOI	https://doi.org/10.5281/zenodo.3845857
persistent identifier	https://treatment.plazi.org/id/03B687E7-C218-2209-FD96-B272FDC2768C
treatment provided by	Carolina
scientific name	Terrobittacus rostratus
status	sp. nov.

Treatment

Terrobittacus rostratus sp. nov.

urn:lsid:zoobank.org:act:35A77A25-C607-46F1-8E5E-869BFC75BCBD

Figs 1–4 View Fig View Fig View Fig View Fig , 9C View Fig

Diagnosis

The new species differs from its congeners by the following characters: 1) wings hyaline without clouded markings; 2) male epandrial appendages boot-shaped in lateral view, upper branch of proctiger broad with two round lateral flanks and a beak-like apex; 3) female subgenital plate black basally, yellowish brown distally, and with a narrow membranous line mesally.

Etymology

The specific epithet is derived from the Latin ‘ rostratus ’ (beak-shaped), referring to the beak-shaped upper branch of the proctiger in the male.

Type material

Holotype

CHINA: ♂, Yunnan Province, Yongde County, Mount Daxueshan , 24°01′30″ N, 99°15′15″ E, 2000 m, 29 Aug. 2015, coll. Ji-Shen Wang ( NWAU).

GoogleMaps

Paratypes

CHINA: 34 ♂♂, 16 ♀♀, same data as holotype, 29–30 Aug. 2015; 20 ♂♂, 20 ♀♀, Yunnan Province, Yongde County, Mount Tanglishan, 24°01′17″ N, 99°14′23″ E, 1400–2000 m, 11–26 Aug. 2015, coll. Ji-Shen Wang ( NWAU).

Description

MEASUREMENTS. Male (n = 20): BL = 11.16 ± 0.94 mm; FL = 15.80 ± 0.42 mm, FW = 3.66 ± 0.19 mm; HL = 13.93 ± 0.39 mm, HW = 3.21 ± 0.13 mm. Female (n = 20): BL = 11.5 ± 0.84 mm; FL = 15.76 ± 1.16 mm, FW = 3.73 ± 0.14 mm; HL = 13.96 ± 1.13 mm, HW = 3.28 ± 0.15 mm ( Fig. 1A View Fig ).

HEAD. Vertex and frons yellowish brown; clypeus lighter than frons; genae pale; labrum yellowish brown, darker basally and laterally; maxillary and labial palps dark brown; fifth segment of maxillary palp slightly longer than fourth ( Fig. 1B View Fig ). Ocellar triangle black; three ocelli almost equal in diameter; median ocellus accompanied with two bristles. Antennae filiform and ciliated; scape and flagellum dark brown, pedicel pale brown; flagellum with distinct segments basally and obscure beyond 13 th segment.

THORAX. Pronotum black, with two long setae on anterior margin, and a few setae on posterior margin. Anterior two-thirds of mesonotum black, remaining part and metanotum unevenly brown; meso- and metascutellum each with two long black setae ( Fig. 1C View Fig ). Pleura unevenly pale brown. Legs yellowish brown, except coxae pale brown, femora and tibiae darker apically ( Fig. 1A View Fig ); fourth tarsomere with one spine on each side; hind basitarsus longer than second and third tarsomeres together.

WINGS. Forewing membrane hyaline and tinged with yellowish brown; pterostigma brown; apical margin slightly infuscate; thyridium at FM conspicuous; two nygmata each in cells R 4+5 and 1R 5; one Pcv; Sc ending beyond the level of FRs; Cuv near level of FM; CuA ending slightly beyond Sc terminus, CuP terminating near level of Scv; Av absent, 1A terminating beyond the level of ORs; apical crossveins roughly arranged in three lines. Hindwings similar to forewings, but Sc terminating at level of midpoint between ORs and FRs; 1A coalesced with CuP subbasally; apical cross-veins fewer than those of forewings ( Fig. 2 View Fig ).

ABDOMEN OF MALE. Terga II–VIII light brown to dark brown, each with a black narrow antecosta; tergum VIII emarginated on posterior margin. Sterna II–VIII pale to dark brown, sternum IX lighter than sternum VIII. Sex pheromone glands single-lobed, each at intersegmental areas between terga VI− VII and between terga VII− VIII ( Fig. 3A View Fig ). Epandrial appendages (tergum IX) yellowish brown, slightly longer than half the length of gonocoxites, boot-shaped in lateral view, with basal third broad and distal two-thirds narrowed toward rounded apex; inner surface with two patches of small black spines each at apex and dorsal process ( Fig. 3 View Fig B–C), and margin from dorsal process to apex also with sparse spines. Tergum X strongly vestigial dorsally with two slender lateral plates extending to base of lower branch of proctiger. Upper branch of proctiger flat, strongly sclerotized with two broad lateral flanks bearing scattered setae, apex curved caudoventrad into a beak; lower branch of proctiger shorter than upper branch, curved downward and tapering apically ( Fig. 3D View Fig ). Cerci conical, almost one-third as long as gonocoxites ( Fig. 3A View Fig ). Gonocoxites yellowish brown, caudal portion with a pale U-shaped membranous area ( Fig. 3E View Fig ). Gonostyli stout basally, distal portion curved cephalad and tapering toward apex. Aedeagus broad basally, with two aedeagal lobes acute and median penisfilum coiled greatly ( Fig. 3A, E View Fig ).

ABDOMEN OF FEMALE. Terga II–IX yellowish brown or unevenly brown, each with a narrow black antecosta. Sterna II–VII yellowish brown, or pale in sterna II–IV and unevenly dark brown in sterna V–VII. Subgenital plate black basally, yellowish brown distally ( Fig. 4A View Fig ), and with a rather narrow membranous line mesally, which is broadened at distal half ( Fig. 4B View Fig ); a pair of acute processes each projecting from lateral margins distally, and extending to anterior edge of tergum IX; distal portion of subgenital plate with long thick setae directed caudad ( Fig. 4 View Fig A–B). Tergum X yellowish brown, extending ventrad. Supraanal plate and subanal plate truncated apically. Cerci setose, slightly longer than supraanal plate.

Distribution

Yunnan Province, China.

Remarks

The new species differs from other species of Terrobittacus in its male epandrial appendages, which is slightly longer than half the length of the gonocoxites.

Terrobittacus rostratus sp. nov. resembles T. longisetus and T. implicatus in general appearance, especially the hook-like proctiger in the male genitalia. However, it can be separated from the latter two species by its boot-shaped epandrial appendages. In addition, wings are devoid of markings in T. rostratus sp. nov., but have clouded markings in the latter two species. Females of T. rostratus sp. nov. can also be differentiated from congeners by the unique coloration of its subgenital plate, which is black basally and yellowish brown distally.