Zaitzeviaria hemisphaerica Bian & Jäch, 2026, sp. nov.
Year: 2026
Type: article
Abstract: Zaitzeviaria hemisphaerica sp. nov. Figs 1 A – D, 4 A – C, 8 A – C Type material (38 specimens). Holotype: China • ♂ (IAECAS): “ China – Shaanxi \ Hanzhong I. [leg.] W [Wang] | Liuba Ca 1400 m \ 8.VI1998 ” [CWBS 317]. Paratypes: China, Shaanxi • 2 ♂♂, 1 ♀ (IAECAS), same data as holotype • 2 ♂♂ (IAECAS): “ China – Shaanxi \ Ningshan I. [leg.] W [Wang] | Xunyangba Ca 1500 m \ 6.VI1998 ” [CWBS 315] • 8 ♂♂, 12 ♀♀ (NMW): “ China: Shaanxi, 6.6.1998 \ Ningshan Co., ca. 1500 m \ ca. 10 km NE Xunyangba \ leg. M. Wang (CWBS 315) ” • 1 ♀ (NMW): “ China: Shaanxi, 7.6.1998 \ 7 km SE Liuba, ca. 1300 m \ Taoyuanpu Village env. \ leg. M. Wang (CWBS 316) ” • 4 ♂♂, 5 ♀♀ (NMW): “ China: Shaanxi, 8.6.1998 \ 2 km SE Liuba, ca. 1400 m \ (Zhangliangmiao) \ leg. M. Wang (CWBS 317) ” • 2 ♂♂ (IAECAS): “ China: Shaanxi \ Foping County \ Changjiaoba Town | 33°34'7"N, 107°58'15"E, \ 1000 m, VI.21.2019 \ Leg. Tong ”. Diagnosis. This species is characterized by a remarkable sexual dimorphism not described for any other Macronychini so far. Especially notable are the inflated male pronotum and the enlarged, conspicuously sinuous, and ventrally hollowed out male protibiae. The aedeagal median lobe has a subtriangular apex and distinct lateral constriction at the distal 0.2. This species is readily distinguished from Z. inflata by the inflated male pronotum and enlarged, sinuous protibiae. In Z. inflata, the male pronotum is not inflated, the protibiae are not sinuous, and the fifth protarsomere is strongly widened and inflated, with variation in the degree of expansion. Description. Male (holotype). BL 1.7 mm, BW 0.75 mm. Habitus as in Fig. 1 A – D. Dorsum black, ventral side dark brown to black, legs ferruginous brown except tarsi yellowish brown. Mouth parts and antennae yellowish brown. Labrum short, smooth, and shiny, lateral margin with fringe of setae, anterior margin almost truncate. Clypeus smooth and shiny, densely punctate, and pubescent. Surface of frons similar to that of clypeus. Antennae 8 - segmented, the first two segments distinctly elongate and inflated, segments 3–7 small, last segment strongly elongate and expanded. Pronotum as in Figs 1 A, 1 C, 4 A (holotype: PL 0.6 mm, PW 0.67 mm), sexually strongly dimorphic. Median groove shallowly impressed, narrow, extending from base to basal 0.8. Sublateral furrows very faint, bisinuous, not carinate. Anterior corners acute, slightly produced; posterior corners nearly rectangular. Elytra as in Fig. 1 A, C (holotype: EL 1.1 mm, EW 0.75 mm), obovate, evenly constricted in distal third. Strial punctures moderately large in basal 0.4, smaller and more widely separated in distal 0.6. Intervals usually flat, rarely somewhat convex, smooth and shiny, each interval with a row of small setal punctures. Intervals VII and VIII carinate from base to basal 0.8. Lateral margin crenulate-serrate. Prosternum as in Figs 1 B, 1 D, 4 B. Prosternal process gradually narrowed from base to narrowly rounded apex. Metaventrite (Fig. 4 C) sexually dimorphic; disc shiny; discrimen distinct, deeply impressed, gradually tapering towards anterior margin; with a row of large punctures posterior of mesocoxae, and with several large punctures anterior of metacoxae. Legs sexually dimorphic. Femora and tibiae densely pubescent and granulate. Ventral side of abdomen as in Fig. 4 C. Basal 0.4 of ventrite I coarse medially; remaining parts of middle of ventrite I, and middle of ventrites II – IV and basal 2 / 3 of ventrite V smooth and shiny, with a few small granules. Lateral areas of ventrites I – V and distal third of ventrite V densely pubescent, sparsely granulate. Males. BL 1.43–1.75 mm, BW 0.72–0.77 mm (n = 10). Pronotum strongly inflated, almost hemispherically vaulted. Anterior margin of elytra with approximately 10–15 densely set granules between scutellary shield and shoulder. Disc of metaventrite medially flat or slightly concave, not clearly convex on both sides of median groove. All femora distinctly thickened; protibia distinctly thickened, subbasally curved mediad (in most specimens) and then evenly curved ventrad (Fig. 1 A, B), ventrally hollowed out with a fringe of long setae inside hollow part; protarsi thickened. Aedeagus (Fig. 8 A – C) long and slender; penis about four times as long as phallobase, almost subparallel in basal 0.8, distinctly constricted in ventral view at apical 0.2, then distinctly tapering towards the subacute apex. Penis distinctly curved in lateral view. Endophallus without distinct sclerotizations; one of the males from CWBS 315 (NMW) has the endophallus everted. Parameres completely fused to penis. Females (Fig. 1 C, D). BL 1.43–1.67 mm, BW 0.73–0.75 mm (n = 10). Pronotum less strongly vaulted. Anterior margin of elytra without or with fewer (less than 10) weakly developed granules. Disc of metaventrite medially flat or convex, more or less vaulted on both sides of the median groove. Femora not distinctly thickened; protibia not thickened and only hardly noticeably curved mediad subbasally, ventrally not hollowed out, without a fringe of long setae. Protarsi not thickened. Distribution. China: Shaanxi. This species is so far known only from four localities in southern Shaanxi Province. Etymology. The epithet is derived from the Latin adjective “hemisphaericus” (= hemispherical) and refers to the strongly vaulted male pronotum.
Authors: Bian, Dong-Ju, Jäch, Manfred A.
Language: English
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W7225647881