Nepalmatoiulus parvulus, Mikhaljova, 2020

Mikhaljova, Elena V., 2020, New data on the fauna of China, part II: the millipede genus Nepalmatoiulus Mauriès, 1983 (Diplopoda, Julidae) in continental China and Taiwan, with descriptions of seven new species, Zootaxa 4852 (1), pp. 101-124 : 113

Nepalmatoiulus parvulus , new species

Figs 47–51

Material examined. Holotype: male ( ZMUM), China, Yunnan Province, Deqen, Tuoxia Highway Mt. Range btw Xiaruolisuzuxiang & Yezhizhen, 27°40´2´´ N, 99°10´29´´ E, H = 4080 m, 13 June 2013, leg. I. Belousov, I. Kabak, G. Davidian ; Paratypes: 2 males ( ZMUM) , 1 male ( FSCB), same locality as in holotype, 13 June 2013, leg. I. Belousov, I. Kabak, G. Davidian.

Diagnosis. Differs from congeners mainly by the posterior gonopod mesomeral processes with frontal excavation but without well-defined subapical outgrowth coupled with the short and broad solenomere.

Description. Male. Length 13–15 mm, midbody vertical diameter 1.0– 1.1 mm, with 45 (–3), 45 (–2), 46 (–2), 46 (–1) segments, excluding telson. Coloration (in alcohol) dark brown with lighter brown metazona. Venter and legs brown, antennae dark brown. Eyes black. Head smooth, sparsely setose, 2 epicranial setae, 4 supralabral setae; not less than 12 labral setae. Eye patches almost oval, composed of about 40 ocelli (in one of the male paratypes). Antennae medium-sized, rather slender and clavate. Gnathochilarium with 7 nonapical stipital setae (in one of the male paratypes). Mandibular stipite with subtriangular rounded smooth lobe; 3 setae on each lamella linguales (in one of the male paratypes). Collum laterally with distinct lower striae of middle length at posterior margin not reaching to anterior margin (but reaching to middle of the collum laterally). Collum dorsally with indistinct more short striae at posterior margin only. A transverse row of sparse setae at hind edge of the collum. Body segments circular. Prozona smooth. Metazona with dense, regular, longitudinal striae reaching hind margin (9–10 striae in an approximate square with sides equal to metazonital length of a dorsal side of midbody ring). Limbus straight, smooth (of Type 1 in Enghoff 1987). A transverse row of thin setae at hind edge of metazonites, setae gradually growing denser toward telson. Ozopores small, lying immediately behind suture dividing pro- and metazona. Caudal dorsal projection of telson of middle length, covered with dense setae and tipped with a small claw-shaped process directed caudad. Preanal ring, anal valves, and subanal scale setose. Legs relatively short and slender. Very delicately serrate ventral pads present on postfemur and tibia, starting from legs 2; the pads somewhat decreasing in size towards telson. The hind most legs without ventral pads. Claw of all legs at base with a relatively short (not longer than claw) setiform accessory claw ventrally but without accessory claw dorsally. Leg pair 1 forming a hook, the distal segment not touching basal segments (“Open hook” type in Enghoff 1987); postfemur with slightly scaly-rugose ventral surface, tip indistinctly wrinkly; coxa with one seta, distal segment without seta and tarsal remnant ( Fig. 50 ). Coxa 2 with one mesapical oral seta, apparently without gland opening (at least the gland openings were not found with using stereomicroscopic equipment). Penis relatively long, slender, about 1.8 longer than wide. Ventral margin of body segment VII with lobes nearly similar to figure 32 in Enghoff 1987. Gonopods slightly protruding. Anterior gonopod flattened, with subparallel margins, apically obliquely rounded. Anterior gonopod in posterior view subapically excavated for accommodation of mesomeral process, distal margins of the excavation papillate, subcentrally with knoblike flattened rudimentary telopodite ( Figs 47, 49 ). Flagellum slender, relatively short, covered with cuticular conical obtuse denticles distally; basal part of the flagellum caudally covered with cuticular spikes ( Fig. 51 ). Opisthomere mesomeral process in distal half with frontal deep excavation but without well-defined subapical outgrowth ( Fig. 48 ). Membranous velum with strongly sloped smooth margin, without a notch near the mesomeral process. Velum smooth. Solenomere short and broad, covered with pointed spines. Margin of accessory membrane smooth.

Female unknown.

Etymology. The specific epithet refers to the small body length and midbody vertical diameter as compared with more large specimens of other new species.

Figures

FIGURES 47–51. Nepalmatoiulus parvulus sp. nov., male paratype. 47, promere, caudal view; 48, opisthomere, mesal view; 49, distal part of promere; 50, leg pair 1; 51, basal part of flagellum. Scales: 10 μm (Figs 49, 51), 20 μm (Fig. 50), 100 μm (Figs 47–48).