Sibiriulus latisupremus, Mikhaljova, Elena V., Nefediev, Pavel S., Nefedieva, Julia S., Sakhnevich, Miroslava B. & Dyachkov, Yuri V., 2014

Mikhaljova, Elena V., Nefediev, Pavel S., Nefedieva, Julia S., Sakhnevich, Miroslava B. & Dyachkov, Yuri V., 2014, Review of the millipede genus Sibiriulus Gulička, 1972, with descriptions of three new species from Altai, Siberia, Russia (Diplopoda, Julida, Julidae), Zootaxa 3866 (1) : -

Sibiriulus latisupremus sp. nov. Mikhaljova, Nefediev & Nefedieva

Figs 4–14 , 40 .

Material examined. Holotype: 1 male ( IBSS), Russia, Siberia, Altai Province, Smolenskoye District, environs of Smolenskoye village, Populus in floodplain of Poperechka River, 21 April 2013, leg. P.S. Nefediev and J.S. Nefedieva. Paratypes: 8 males, 22 females, 24 juveniles, 3 fragments (ASU), Russia, Siberia, Altai Province, Smolenskoye District, environs of Smolenskoye village, Salix in floodplain of Poperechka River, 27 August 2000, leg. P.S. Nefediev and J.S. Romanova; 1 male ( IBSS), Russia, Siberia, Republic of Altai, Shebalino District, Kumalyr, Larix sibirica forest, 11 August 2006, leg. A.S. Babenko; 1 male, 2 females (ASU), Russia, Siberia, Altai Province, ca. 5 air-km NW of Aya village, environs of Lake Aichenok, Betula stand on bank, 6 July 2010, leg. P.S. Nefediev; 1 male, 1 female ( IBSS), Russia, Siberia, Altai Province, ca. 5 air-km NW of Aya village, environs of Lake Aichenok, Betula forest on hill slope W from Lake Aichenok, 7 July 2010, leg. P.S. Nefediev; 5 males, 13 females, 13 juveniles (ASU), 9 males, 11 females, 9 juveniles ( IBSS), together with holotype, 21 April 2013, leg. P.S. Nefediev and J.S. Nefedieva.

Material re-examined (specimens published by Mikhaljova & Nefediev 2003, Mikhaljova et al. 2007). 13 males, 20 females, 8 juveniles, 1 fragment (ASU), 1 male, 1 female ( IBSS), 1 male, 1 female ( ZMUM), Russia, Siberia, Altai Province, Smolenskoye District, environs of Smolenskoye village, bank of Poperechka River, Salix , 27 August 2000, leg. P.S. Nefediev; 1 male, 4 females (ASU), Russia, Siberia, Altai Province, Smolenskoye District, environs of Smolenskoye village, bank of Poperechka River, Salix , 31 May 2002, leg. J.S. Nefedieva.

Diagnosis. Differs from congeners mainly by the distal part of the gonopod mesomere being broad in lateral and mesal views as well as the shape of the gonopod opisthomere (its caudal surface convex (almost at a right angle), its apical part with short pointed process mesally).

Description. Male. Length about 12–13 mm, vertical diameter 0.6–0.7 mm (the overwhelming majority of males show a vertical diameter of 0.6 mm), with 42(–3), 44(–2), 44(–3), 46(–2) body segments, excluding telson. Coloration dark brown or brown. Clypeolabral region of head with light marbled spots. Collum with two transversely, large, marbled spots. Telson and segments in front of telson lighter or not. Antennae and legs brown.

Eye patches composed of at least 30 ocelli. Labral setae 8+8. Antennae in situ extending behind to segments 4–5. Length ratios of antennomeres 2–7 as 6.3:3.6:3.3:4.6:2.6:1, width ratios as 1.2:1.5:1.5:1.8:1.6:1, respectively. Distodorsal corolla of antennomeres 5 and 6 each with not less than 6 and not less than 8 sensory bacilli, respectively ( Fig. 4 ).

Gnathochilarium ( Fig. 5 ) as typical of the genus. Four setae on each lamella lingualis arranged longitudinally nearly at regular intervals.

8–9 striae on metazonital surface between dorsal midline and ozopore. Short caudal projection of telson epiproct somewhat flattened dorsoventrally, covered with dense, relatively long setae, its tiny claw-shaped process directed caudad. Preanal ring of telson densely setose. Anal valves very densely setose.

Legs with broad, very delicately serrate sole pads on tibiae and postfemora; these pads gradually growing reduced towards posterior body end to totally disappear on last legs. Claw ( Fig. 6 ) as typical of the genus.

Leg pair 1 ( Fig. 7 ) and leg pair 2 ( Fig. 8 ) as typical of the genus. Penes subtriangularly notched at tip. Gonopods as in Figs 9–12 . Gonopod meso- and opisthomere subequal in height but higher as compared with promere. Flattened promere ( Fig. 10 ) with rounded apex, its caudal surface covered by papillae nearly throughout. Flagellum medium length, filiform distally. Mesomere ( Fig. 11 ) slightly bent caudad; its front surface as plate, densely papillate, with longitudinal lowering along middle (the median lowering not conspicuous in Fig. 11 because the mesomere is somewhat twisted to the left). The mesomere distal part broad in lateral and mesal views.The mesomere apex with a broad fovea. Opisthomere ( Figs. 9, 12 ) with convex (almost at 90˚) caudal surface and with short pointed apical process (a) (? phylacum) mesally. Solenomere with elongated narrowed apex. Interior parabasal spine (s) relatively well-developed. Membranous velum (v) narrow with a pointed tip.

Female. Length about 14–17 mm, vertical diameter about 1.0 mm, with 44(–3), 44(–2), 45(–4), 45(–3), 46(–2), 47(–2), 48(–2) segments, excluding telson. Leg pairs 1 and 2 scarcely thicker than the other legs. Other nonsexual characters as in male.

Vulva as in Figs 13–14 . Operculum with semicircular or subtriangular apical incision. Lateral longitudinal row of setae on operculum with 4–10 setae and mesal one with 3–7 setae. 11–20 setae on posterior median bursal sclerite; 7–18 setae on lateral and mesal sclerites of the bursa together. Apical setae longest.

Juvenile. Shorter, length of examined specimens about 6.0–9.0 mm, vertical diameter about 0.5 mm, with 34(–7), 37(–5), 39(–5), 39(–4), 40(–4), 41(–5), 41(–4) segments, excluding telson.

Name. The specific epithet refers to the broad apex of gonopod mesomere (in lateral or mesal view).

Remarks. Restudy of the males and females from the Altai Province, Smolenskoye District, near Smolenskoye village, collected 27 August 2000, which were determined as Sibiriulus multinicus (see Mikhaljova & Nefediev 2003, Mikhaljova et al. 2007), shows that these specimens belong to Sibiriulus latisupremus sp. nov.

Figures

FIGURES 4 – 8. Sibiriulus latisupremus sp. nov., male. 4, distal part of antenna; 5, gnathochilarium; 6, claw of midbody leg; 7, leg pair 1 (front view); 8, leg pair 2 and penes (caudal view).

FIGURES 9 – 12. Sibiriulus latisupremus sp. nov., male. 9, gonopods (mesal view); 10, gonopod promere (caudal view); 11, gonopod mesomere (front view, somewhat twisted to the left; the median lowering not conspicuous); 12, gonopod opisthomere (lateral view); a, apical process of gonopod opisthomere; s, interior parabasal spine of gonopod opisthomere; v, velum.

FIGURES 13 – 14. Sibiriulus latisupremus sp. nov., female. 13, right vulva (lateral view); 14, left vulva (caudal view).

FIGURES 38 – 40. Sibiriulus baigazanensis sp. nov., male holotype (38); Sibiriulus aktashensis sp. nov., male paratype (39); Sibiriulus latisupremus sp. nov., male paratype (40). Habitus in lateral view. Photographed not to scale.