Nepalmatoiulus muli, Mikhaljova, 2020

Mikhaljova, Elena V., 2020, New data on the fauna of China, part I: the taxonomy of the millipede family Julidae (Diplopoda), Zootaxa 4729 (1), pp. 47-66 : 53-55

Nepalmatoiulus muli new species

Figs 22–37

Material examined: Holotype: male ( ZMUM), China, Sichuan Province, S Muli, 3685 m asl., 27°45´38´´ N, 101°15´54´´ E, 20 May 2012, leg. I. Belousov, G. Davidian, I. Kabak, Korolev. Paratypes: 2 females ( ZMUM), same locality as in holotype, 20 May 2012, leg. I. Belousov, G. Davidian, I. Kabak, Korolev.

Diagnosis. Differs from congeners mainly by the presence of long subapical branch of posterior gonopod solenomere, coupled with slender stick-shaped apically papillate mesomeral process of opisthomere and the configuration of velum.

Description. Male. Length about 25 mm, vertical diameter 3.0 mm, with 53(–1) rings, excluding telson. Coloration in alcohol dark gray, with a broad dorsal light gray longitudinal stripe, dark middorsal line, dark brown narrow transverse line on caudal margin of each metazonite. Head and legs dark brown, eyes black. Gnathochilarium marbled brown with yellow distal part. Apical portion of the mandible stipital lobe with yellow border. Head smooth, 2 epicranial setae, 4 supralabral setae, 22 labral setae, and a group of about 10 setae on each lateral side below of antenna. Eye patches subtriangular, each composed of about 70 ocelli. Antennae medium-sized, rather slender and clavate; length and width ratios of the antennomeres as in majority of Nepalmatoiulus species. Gnathochilarium: not less than 20 nonapical stipital setae; lamellae linguales each with 6–7 setae arranged longitudinally. Mandibular stipite with subrectangular rounded smooth lobe; apical portion of lobe with well demarcated border. Collum laterally with several distinct lower striae extending from posterior to anterior margin, dorsally with short striae at posterior margin only. Length of the collum striae gradually decreasing toward dorsum. Posterior edge of the collum with very sparse setae. Body cylindrical. Prozona smooth. A metazonite gradually growing narrower toward ventral part of body. Suture between pro- and metazonite distinct. Metazona with dense, regular, longitudinal striae reaching hind margin (18–19 striae in an approximate square with sides equal to metazonital length of a midbody ring dorsal part). A transverse row of sparse, thin setae at hind edge of metazonites, setae gradually growing denser and longer toward telson. Ozopores small, lying behind suture dividing pro- and metazona, in touch with suture only in anterior body part, set off from the suture in the second half of the body. Limbus straight, smooth (of Type 1 in Enghoff 1987).

Telson entirely densely setose. Epiproct caudal process of middle length, carrying at tip a claw-shaped process curved dorsally. Legs relatively short and slender. Very delicately serrate ventral pads present on postfemur and tibia, starting from legs 2; pads decreasing in size towards telson, nearly totally disappearing on postfemur of last legs. Claw of all legs at base with a relatively long (not longer or slightly longer than claw) setiform accessory claw ventrally but without accessory claw dorsally ( Fig. 31 ). Leg pair 1 forming hook, the distal ring not coming into close contact with the basal rings (“open hook” type in Enghoff 1987), ventral surface of the prefemur, femur, postfemur and tip delicately wrinkly, coxa with one seta, distal ring without setae, tarsal remnant minute ( Fig. 24 ). Right leg 2 smaller than left one (apparently a deformity). Coxa 2 with one mesapical oral seta, gland opening positioned in central and axial position ( Fig. 22 ) according to Enghoff (1987). Penis pear-shaped, about 1.5 times longer than wide, with apical excavation ( Fig. 23 ). Ventral margins of body ring VII with ventrad subtriangular apically rounded lobes ( Fig. 25 ). Gonopods slightly protruding. Anterior gonopod flattened, with subparallel margins, apically obliquely rounded, subapically slightly excavated for accommodation of mesomeral process, distal margin of the excavation slightly papillate; posterior surface subcentrally with knoblike flattened rudimentary telopodite ( Figs 26–28 , 36 ). Flagellum slender, relatively short, caudally covered with cuticular conical obtuse denticles in distal part ( Fig. 30 ). Basal part of the flagellum covered with cuticular spikes ( Fig. 29 ). Opisthomere with slender stick-shaped mesomeral process apically papillate ( Figs 32–33 , 37 ). Velum with smooth margin without a small notch near the mesomeral process. Margin of accessory membrane (m) denticulate. Solenomere densely spinose throughout, with long subapical branch (b) caudally covered with spines (the base of the subapical branch is hard to see in figure 33).

Female. Length about 30 mm, vertical diameter 4.0 mm. Head with a group of not less than 5 setae on each lateral side (below antenna). Gnathochilarium with not less than 10 nonapical stipital short setae.

Vulva ( Figs 34–35 ) with operculum and bursa of about equal height; apical excavation indistinct, apical lobes of bursa not long; posterior median plate with not less 40 setae arranged irregularly; lateral and mesal bursal sclerites each with not less than 10 setae; operculum with not less than 14 setae.

Etymology: The specific epithet refers to the type locality, a noun in apposition.

Figures

FIGURES 22–33. Nepalmatoiulus muli sp. nov., male holotype. 22, coxa 2, front view; 23, penis, front view; 24, leg pair 1, front view; 25, ventral margin of body ring VII; 26, promere apex, caudal view; 27, promere, caudal view; 28, promere telopodite; 29, basal portion of promere flagellum; 30, distal portion of promere flagellum; 31, claw 2; 32, apex of opisthomere mesomeral process; 33, opisthomere, mesal view; m, accessory membrane; b, solenomere subapical branch. Scales: 2 μm (Figs 29–30, 32), 10 μm (Figs 26, 31), 20 μm (Fig. 22), 100 μm (Figs 23–25, 27, 33), without scale (Fig. 28).

FIGURES 34–35. Nepalmatoiulus muli sp. nov., female paratype. 34, vulva, front view; 35, vulva, caudal view. Scales: 100 μm.

FIGURES 36–37. Nepalmatoiulus muli sp. nov., male holotype. 36, promere, caudal view; 37, gonopod, mesal view, slightly rotated around its axis. Scales in mm.