Hypocambala zizhongi Jiang & Zhang & Chen & Xie 2021, new species

Hypocambala zizhongi, new species

Figs 1, 4–22

Type material: Holotype male, China: Yunnan Province, Dali City, Nanjian County, Bixi Town, Banpo Village, Banpo Cave, 24.933436° N, 100.314361° E, alt. 1933 m, 24 October 2018, X.K. Jiang & Z.Z. Yang leg. (IBGAS). Paratypes: 17 males and 45 females, same locality and date as holotype (IBGAS); 20 males and 30 females, same locality, 16 September 2009, H.M. Chen leg. (IBGAS).

Etymology: This specific name is after Prof. Zizhong Yang (Dali University, China), who was one of the collectors.

Diagnosis: This species can be distinguished from other species of this genus by the following combination of characters: collum and metazonae smooth, densely hairy [with crests in H. oligotricha and H. vietnamicus; hairless in H. cornuta (Verhoeff, 1939), H. oligotricha, H. vietnamicus and H. voeltzkowi (Attems, 1910); with at most three transverse rows of short hairs in H. anguina (Attems, 1900), H. caledonica (Carl, 1926), H. dahli (Attems, 1914) and H. gracilis (Attems, 1938)] (Figs 1, 4, 7–11); coxosternum of male legs I with a pair of curved and widely separated processes (without in H. voeltzkowi) (Fig. 14); prefemur of male legs I with a tubular process [without in H. anguina, H, cinctella (Carl, 1926), H. crinita (Attems, 1914), H. gracilis, H. orientalis (Carl, 1912) and H. voeltzkowi] (Figs 14, 15); tip of coxite process of anterior gonopod uncate (straight in H. dahli, H. gracilis, H. orientalis and H. voeltzkowi) (Figs 18, 19); flagellum of posterior gonopod bifid (not bifid in all other species) (Figs 20–22).

Description: Body moniliform, thread-like (Fig. 1), 14–24 mm long, 0.8–0.9 mm wide (holotype body length and width, 17 and 0.8 mm, respectively). Body with 37–57 podous and 1–3 apodous rings (holotype with 47 podous rings and 1 apodous ring). Color generally greyish yellow, with reddish brown ozopores and a dark dorsal midline from anterior part to the last trunk ring (Fig. 1).

Head convex and smooth, with straight dense hairs (Fig. 4). Eye patch oval, with about 10–20 pigmented ommatidia, arranged in 2–5 irregular linear rows. Antennae slender, densely setose. Relative antennomere lengths 6±2>3±4±5>1±7. Antennomeres 2–5 clavate, terminal part of antennomere 5 obviously expanded. Antennomeres 6 and 7 cylindrical. Antennomeres 5 and 6 each with a line of bacilliform sensilla distodorsally. Last antennomere with four terminal sensory cones (Figs 4, 12). Labrum with three teeth anteromedially (Fig. 6). Gnathochilarium with a separate promentum, oligotrichous. Medial part of mentum with longitudinal wrinkles (Fig. 5). Collum slightly broader than head, convex, smooth; densely setose, lateral margin with faint longitudinal striations (Fig. 4). Prozonae hairless, rear with fine longitudinal striations. Metazonae smooth, covered with dense hairs in dorsal and lateral areas (Figs 7, 8), with fine longitudinal striations, hairless on venter (Fig. 9). Ozopores small, starting with body ring 5 (Fig. 8). Sterna smooth, hairless (Fig. 9). Telson with dense hairs (Figs 10, 11). Epiproct smooth, elongated posteriorly. Paraprocts convex, without lateral depression. Hypoproct crescent-shaped. Walking legs slender, nearly as long as body width (Figs 7, 9), with a fine accessory claw (Fig. 13).

Male legs I strongly modified, coxosternum with a pair of subdigitiform and forward-curved processes, situated medially, set off from each other, with several strong setae at distal margin (Fig. 14). Prefemoral process short, cylindrical, with a slightly expanded and hollow tip and several tangled distal setae (Fig. 15). Other podomeres of telopodite normal, slightly reduced in size. Male legs II slender (Fig. 16). Penes short and small, about one-half as long as coxa, with one distal seta (Fig. 16). Male legs III with a strongly elongated coxa (Fig. 17).

Gonopods. In posterior view, coxite of anterior gonopods large and nearly rectangular with micro-setae present at mediodistal margin, three short setae at medial margin (Fig. 18). Distal part of coxite with a ridge extending from mediodistal margin to telopodite joint (Fig. 18). Coxite processes small, hook-like with rounded tips, situated mediodistally (Figs 18, 19). Telopodite short, digitiform; placed laterally, with several distal setae and a small field of microsetae at base (Figs 18, 19). In anterior view, anterior part of coxite of posterior gonopod with an oval-shaped, sunken field of numerous strong microsetae (Fig. 20). In posterior view, coxite of posterior gonopods plate-like, with mediolateral part expanded and bearing a row of strong and curved setae at mediolateral margin (Fig. 21). Flagella short, bifurcated, with tiny spines on surface, situated at tip of coxite (Figs 20–22).

Distribution: Known only from the type locality.

Remarks: With a smooth and hairy body surface and the details in the male first leg-pair and gonopods, this species obviously belongs to Hypocambala. Most species of Hypocambala are distributed on islands of the Pacific and Indian oceans. Only H. gracilis and H. helleri are found in the Indochina Peninsula, the latter species also distributed in the Moluccas, Sulawesi and the Seychelles. With the discovery of this new species and the revised placement of H. polytricha, H. zizhongi sp. nov. is the only Hypocambala recorded from China and expands the distributional range of this genus to the north to nearly 25 degrees north latitude.