Skleroprotopus multistriatus, Chen & Zhao & Golovatch & Liu, 2024

Chen, Rong, Zhao, Yi, Golovatch, Sergei & Liu, Wei-Xin, 2024, Molecular phylogenetic and morphological studies reveal increased species diversity in the millipede genus Skleroprotopus Attems, 1901 in China (Julida: Mongoliulidae), Arthropod Systematics & Phylogeny 82, pp. 659-691 : 659-691

3.3. 11. Skleroprotopus multistriatus sp. nov.

Figures 3 G , 14

Material examined.

Holotype male ( SCAU), China, Zhejiang Province, Hangzhou City, Jiande City, Cave Shenxian Dong , 29°23′27.83′′N 119°5′41.26′′E, 150 m, 27. XII. 2018, Tian Mingyi, Cheng Jingli, Qin Zhuanghui and Chen Mengzhen leg. Paratypes: 22 males, 12 females ( SCAU), same data as for holotype .

Diagnosis.

Differs from congeners mostly based on the following combination of characters: (1) collum with 10–16 lower striae and 18–27 longitudinal striae laterally on metazona (Fig. 3 G ). (2) telopoditomere 4 of male leg-pair 1 with two small mesal humps (Fig. 14 D ); (3) penis stout, distally sharpened, much shorter than coxae 2 (Fig. 14 C ); (4) male leg 7 with a very small coxal process, only slightly higher than 2 - segmented telopodite (Fig. 14 E ); (5) anterior gonopod (Fig. 14 G, H ) with a very long and slender coxal process carrying a narrow, lower, membranous lobe, distally with a vague indentation. — In addition, this new species differs from all other Skleroprotopus species analyzed in uncorrected p - distances ranging from between 8.0–8.3 % (compared to S. incisodentatus sp. nov.) and 14.6 % (compared to S. longissimus sp. nov.).

Etymology.

The species is named after the more numerous striae on the collum and metazona; adjective.

Description.

Length of males ca 29.5–34.5 mm, 1.8–2.0 mm in diameter, body with 53–59 podous + 1 apodous rings + telson. Length of females ca 34.0–37.0 mm, 1.9–2.1 mm in diameter, body with 57–62 podous + 1–2 apodous rings + telson. Coloration in alcohol (Fig. 3 G ) generally marbled dark brownish, antennae and legs light brownish. Eye patches blackish, subtriangular, arranged in 4–6 irregular rows, altogether about 26–36 ommatidia per eye patch.

Head capsule smooth and hairless, eyes slightly bulged, epicranial suture well-defined. Labral margin with 2 + 2 supra-labral and 9 + 9 labral setae. Antennae long and slender, reaching behind to middle of ring 4 when stretched dorsally. In length, antennomeres 3> 2> 5> 4> 6> 7> 1 (Fig. 14 F ). Antennomeres 5 and 6 (Fig. 14 F ) each with a distal corolla of sensilla basiconica. Mandibular stipes well-rounded in male, even more strongly rounded in female. Gnathochilarium with at least 5 setae on each lamella lingualis (ll); promentum (pr) lute-shaped, anteriorly swollen and very narrow in males (Fig. 14 B ), vs a narrow, oblong and rhomboid pr in females (Fig. 14 A ).

Collum with 10–16 lower striae laterally, but lowest 4 striae not reaching the anterior margin. Prozona with 2–6 irregular subtransverse striae and metazona with 18–27 longitudinal striae laterally (Fig. 3 G ). Suture dividing pro- and metazona very narrow, a regular comb. Ozopores starting with ring 6, lying mid-laterally on sides of metatergites.

Epiproct slightly protruding caudad, posterior margin with 4 + 4 setae. Paraprocts convex, with 1 + 1 setae. Hypoproct eye-shaped, with 1 + 1 setae.

Legs medium-sized, about as long as midbody height. Male leg-pair 1 (Fig. 14 D ) hypertrophied, 5 - segmented, strongly curved anteriad; Coxa (cx) and telopoditomeres 1 and 2 (t 1, t 2) with some scattered long setae. Telopoditomere 3 (t 3) longest, about 1.5 × as long as telopoditomere 4 (t 4), t 4 irregularly shaped, caudally densely setose, subapically with two small mesal humps (h). Male leg-pair 2 (Fig. 14 C ) reduced in size and somewhat stout; coxae (cx) elongated, penis (pn) very stout, much shorter than cx, distal part sharpened, seta absent. Male leg-pair 7 (Fig. 14 E ) strongly reduced, each leg with a 2 - segmented asymmetrical telopodite (te), telopoditomere 1 (t 1) with several long setae; coxal process (cp) very small, slightly higher than te, medial margin and distally densely setose.

Anterior gonopods (Fig. 14 G, H ) with a very long and narrow coxal process (cp) bearing a row of short villi in anterior view, posteriorly carrying with a low, narrow, membranous lobe (ml), outer margin of ml smooth, with a vague indentation distally. Flagellum (f) very long and slender, distally branched and villose. Telopodite (te) about 2 / 3 as long as cp, with long setae at mesal margin and apically, laterobasally with a minute remnant (r) a second podomere.

Posterior gonopods (Fig. 14 I ) erect, branched distally, anterior branch smooth, with a very small and pointed tip, posterior one densely setose.

Vulva (Fig. 14 J ) as usual, with two parallel rows of short setae on both anterior and posterior surfaces; operculum (op) with 3 long distal setae.

Remarks.

Based on the pigmented body, black eyes, as well as moderately long legs, S. multistriatus sp. nov. is rather to be considered as a troglophile.

Figures

Figure 3. Habitus of some Skleroprotopus species in lateral view. A Skleroprotopus penglai sp. nov.; B Skleroprotopus longiflagellatus sp. nov.; C Skleroprotopus tiankeng sp. nov.; D Skleroprotopus ampullaceus sp. nov.; E Skleroprotopus conicus sp. nov.; F Skleroprotopus yutiantianae sp. nov.; G Skleroprotopus multistriatus sp. nov.; H Skleroprotopus change sp. nov. Scale bars: 5.0 mm.

Figure 14. Skleroprotopus multistriatus sp. nov. . A, J female paratype; B – I male paratype. A, B gnathochilarium; C leg 2 with penis, posterior view; D legs 1, anterior view; E legs 7, anterior view; F right antenna, lateral view; G anterior gonopods, anterior view; H anterior gonopods, posterior view; I posterior gonopods, anterior view; J right vulva, mesal view. Abbreviations: a 5, a 6, antennomeres 5, 6; cp, coxal process; cx, coxa; f, flagellum; h, hump; ll, lamella lingualis; ml, membranous lobe; op, operculum; pn, penis; pr, promentum; r, remnant; t 1 – t 4, telopoditomeres 1–4; te, telopodite. Scale bars: 0.2 mm.