Bittacus echinatus Hua et Huang

Hua, Baozhen, Tan, Jiangli & Huang, Pengying, 2008, Two new species of the genus Bittacus (Mecoptera: Bittacidae) from China, Zootaxa 1749, pp. 62-68 : 65-67

Bittacus echinatus Hua et Huang , sp. n.

( Figs 3–5 )

Holotype: male, CHINA: HENAN: Mt. Baiyunshan (33°42 N, 111°55 E), alt. 1500 m, Songxian County, 18.viii.2004, coll. J.L. Tan.

Paratypes: CHINA: HENAN: 2ΨΨ, same data as holotype. CHINA: SHAANXI: 2ΨΨ, Foping County, 20.vii.1996; 1, Mt. Nanwutai (33°58 N, 108°55 E), Chang’an County, 29.vii.2005, coll. X.L.Du.

Dignosis

The new species is close to B. trapezoideus Huang et Hua, 2005 , from Gansu Province, but can be separated from the latter by one Pcv, Av absent; tergum 10 very short with posterolateral corner extending ventrad, not as a saddle-shaped plate as other species. Epandrial appendages are shorter than half length of gonocoxites, furnished with black spines on inner surface of apex, protruding as a tooth basal-ventrally. The two halves of female subgenitale fused, with central portion blackish.

Description based on specimens preserved in 70% ethanol.

Head. Vertex and frons brown, rostrum darker. Antennae light brown, 5.4 mm long, filiform with 17 hairy flagellomeres, but the apical 5 flagellomeres segmented indistinctly. Eyes dark brown. Ocellar triangle black with 2 black setae above mid-ocellus.

Thorax. Pronotum dark brown, with two long black setae on anterior margin. Propleuron dark brown with seven long setae near anterior edge. Mesonotum glabrous, shining dark brown, nearly black on most elevated parts with two long setae near wing base; scutellum abruptly paler, yellowish brown. Metanotum yellowish brown. Pleural and ventral surfaces, coxae and mera whitish brown. Legs brown with some short black setae on femora, tibiae, and tarsi; distal end of femora and both ends of tibiae dark brown; tibia with two apical spurs of almost equal length.

Wings ( Fig. 3 ). Forewing 16.8 mm long, 4.2 mm wide. Wings narrow with obtusely angulated apex; membrane hyaline with light yellow tinge. Pterostigma prominent, blackish brown; four conspicuous blackish brown markings each at OM, ORs, FRs and distal margin of CuP; noticeable blackish brown clouding along most cross veins. A clear thyridium with distinct border at first fork of media (FM). Vein 1A terminating before the level of FM; cubical crossvein (cuv) at the level of FM. One Pcv present; Av absent. Hindwing 14.5 mm long, 3.5 mm wide; markings similar to forewings.

Abdomen of male (Figs. 4A–C). Terga 2–5 yellowish brown with mid of posterior margin darker; terga 3– 5 each with a narrow black antecosta; terga 6–8 light brown, each with a narrow black antecosta; tergum 8 deeply concave posteriorly; tergum 9 modified into epandrial appendages, yellowish brown; the corresponding sterna similarly colored; gonocoxites dark brown. Epandrial appendages very small, shorter than half length of gonocoxites, subquadrate in shape from lateral view and truncate at apex, but produced ventrally at base (Fig. 4A); from dorsal side, epandrial appendages furnished with thick black spines on inner surface of apex, lateral projection tooth-like (Fig. 4C). Tergum 10 a simple transverse dorsal plate with each posterior corner narrowly extending posteroventrad and thence curved dorsad around base of cercus to form a large roughly triangular area mesal to cercus, with no setae. Upper branch of proctiger protruding between bases of epandrial appendages, with rounded apex furnished with a bundle of setae; lower branch of proctiger very short, broad basally and sharply tapering toward apex. Cerci rather short and slender. Gonocoxites very large in size, posteroventrally rounded (Fig. 4A). Gonostyles very short, mesally curved with apex bluntly rounded, bearing numerous brown setae (Figs. 4A–B). Aedeagus slender, with greatly coiled elongate penisfilum and a small acute basal lobe.

Abdomen of female (Figs. 4D–G). Terga 2–5 light brown, with middle of posterior margin dark brown. Terga 3–5 each with a narrow black antecosta. Tergum 6 blackish brown, moderately long with a prominent trace of antecosta. Sternum 7 narrow, brown, without noticeable trace of antecosta. Tergum 8 blackish brown, short, with a narrow antecosta. Tergum 9 blackish brown, with a narrow antecosta (Fig. 4D). Subgenitale rectangular with central portion blackish; a pair of slender processes projecting back from posterior corner; in ventral view subgenitale broad with a number of black stiff setae; the two halves almost completely connected, with a very narrow suture not extending to apex (Fig. 4E). Tergum 10 brown, narrow, deeply extending ventrad. Supraanale, subanale and cercus brown; subanale and supraanale short and broad, equal in length, and hind margins emarginated (Fig. 4F). Cerci slender, brown, moderately long (Fig. 4G).

FIGURE 4. Bittacus echinatus , sp. n.: A, male terminalia, lateral view; B, gonostyle of male, lateral view; C, terga 8–9 of male, dorsal view; D, female terminalia, lateral view; E, subgenitale of female, ventral view; F, abdominal segment 10 of female, dorsal view; G, ibid, ventral view. a—anus; ac—antecosta; c—cercus; gst—gonostyle; gx—gonocoxite; loaedeagal lobe; pf—penisfilum; sap—subanale; sgp—subgenitale; spap—supraanale; st—sternum; te— tergum.

Egg ( Fig. 5). Spherical in shape, 0.6 mm in diameter. Pale with yellowish tinge when newly deposited but turning dark brown several hours later. Tough and thick chorion covered with numerous granules. The egg is very unique for its appearance looking like a terrestrial globe with distinct grid of latitudes and two poles decorated with special pattern. In all species of bittacids studied to date, this is the first time that a globe-shaped pattern of chorion has been reported.

Distribution. Shaanxi and Henan Provinces, China.

Etymology. The specific name echinatus is derived from the Latin, referring to the black spines along the apex of the epandrial appendages of the male.

Figures

FIGURE 3. Bittacus echinatus, sp. n., Wings.