Nepalella brevichaeta, Mikhaljova, 2022

Mikhaljova, Elena V., 2022, Contributions to the millipede fauna of China: five new species of the genus Nepalella Shear, 1979 (Diplopoda, Chordeumatida, Megalotylidae), Zootaxa 5196 (3), pp. 388-406 : 389-391

Nepalella brevichaeta sp. nov.

Figs 1–15

Material examined. Holotype: male ( ZMUM), China, Yunnan [Province], [Lijiang City], Laojunshan sources of river above Shangliju , 26˚44′36′′ N, 99˚36′26′′ E, H= 3215 m, 26.06.2014, leg. I. Belousov, I. Kabak.

Diagnosis. Differs from congeners mainly by the posterior gonopod colpocoxites forming a heart-shaped figure with boat-shaped outgrowths (bo) laterally ( Figs 10, 12 , 14 ), by the male coxa 10 with a large curved process (cp), by the male prefemur 10 with a thin finger-shaped process (pf) ( Figs 4, 6 ) and by very short metazonital macrochaetae.

Description. Male. Length in alcohol about 29 mm, width about 3.0 mm with dorsolateral bulges. Coloration in alcohol light beige with small brown spot at base of each metazonital macrochaeta. Antennae brown. Head marbled brown. Distal parts of pregonopodal legs marbled brown; distal parts of postgonopodal legs marbled brownish. Eye patches black.

Body with 30 rings (including telson). Head sparsely setose. Antennae very long and slender. Eye patches subtriangular, with about 30 ommatidia. Collum semicircular. Both collum and ring 2 narrower than head with genae. Ring 2 somewhat wider than collum. Body width gradually increasing until ring 6, body parallel-sided on rings 7–18(19), thereafter gradually tapering. Paraterga poorly developed, with small dorsolateral bulges on rings 6–18, reduced on rings 19–25, onward missing. Metazonital macrochaetae very short, fragile, arranged in a transverse row on rings 27–29, in a subtransverse row on rings 20–26, like an extended (to different degrees) triangle on preceding rings. All macrochaetae pointed. Axial suture well-developed.

Legs long and slender. Leg pairs 1 and 2 typically reduced in size, with usual tarsal brushes. Other pregonopodal legs just barely enlarged. Starting from legs 3, walking legs with abundant, as funnels with operculum, tarsal papillae; their quantity gradually decrease toward end of body. Midbody legs with tarsal papillae occupying about 3/4 of the tarsus length. Hindmost legs without tarsal papillae.

Claws invariably long, sabre-shaped. Claws of pregonopodal and postgonopodal legs, including legs 10 and 11 ( Fig. 5 ), at base with two small additional claws dorsally only. Femora 3 with small protuberance. Femora 4 and 5 with mushroom-shaped mesal protuberance ( Figs 1, 3 ). Coxa 7 with thin, anterior finger-shaped process (p) covered with small low papillae ( Fig. 2 ).

Legs 10 and 11 with coxal glands. Coxa 10 with large, curved anterolaterad, process (cp) pierced by a channel with protruding flagellum ( Figs 4, 6 , 7 ). Prefemur 10 with a distomesal, thin, finger-shaped process (pf) partly covered with minute papillae ( Fig. 4 ). Prefemur 11 with a basal, digitiform, partly papillate process (d) ( Fig. 9 ). Sternum 11 frontally with a longitudinal, thin, shallowly sinuate ridge rounded in its basal part.

Anterior gonopods (ag) reduced, sternum with a median subconical lobe (ml); coxites (cxi) of medium length, straight, nearly bottle-shaped ( Figs 11 , 15 ). Posterior gonopod colpocoxites curved mesad and as a result they form a heart-shaped figure ( Figs 10 , 14, 15 ). The colpocoxite apices thin, directed ventrad ( Fig. 8 ). In caudal view the colpocoxite distal half with a lateral, boat-shaped outgrowth (bo) carrying the orifice of a seminal groove (sg) ( Figs 10, 12 , 14 ). Posterior gonopod basal half with a hair-like structure (b) (a homologue of the bush-like structure of other species); angiocoxite (a) with elongate, near pointed projection (ap) on posterior face ( Figs 10 , 14 ). In frontal view the colpocoxite with a tongue-like wrinkled blade (bl) along its length; angiocoxite (a) convex, rounded on anterior face ( Figs 13 , 15 ). Posterior gonopod telopodites large; telopoditomere 1 densely setose on its frontal face; telopoditomere 2 with a claw vestige apically.

Female unknown.

Etymology. To emphasize the very short metazonital macrochaetae; adjective.

Figures

FIGURES 1–6. Nepalella brevichaeta sp. nov., male holotype (ZMUM). 1. Leg 5, frontal view. 2. Coxae and trochanters of legs 7, frontal view. 3. Mushroom-shaped protuberance, frontal view. 4. Basal part of leg pair 10, frontal view. 5. Claw of leg 11, caudal view. 6. Apices of leg pair 10 coxal processes, frontal view. Abbreviations: cp, coxal process; p, coxal process of leg 7; pf, prefemoral process. Scales: 10 μm (Fig. 3), 20 μm (Figs 5, 6), 100 μm (Figs 1, 2), 200 μm (Fig. 4).

FIGURES 7–13. Nepalella brevichaeta sp. nov., male holotype (ZMUM). 7. Apex of leg 10 coxal process, frontal view. 8. Apices of posterior gonopod colpocoxites, frontal view. 9. Basal part of leg 11, caudal view.10. Posterior gonopods, caudal view. 11. Anterior gonopods, caudal view. 12. Distal part of posterior gonopod colpocoxites, caudal view. 13. Posterior gonopods, frontal view. Abbreviations: a, angiocoxite; ap, angiocoxal projection; b, hair-like structure; bl, anterior colpocoxital blade; bo, boat-shaped outgrowth; cxi, coxite; d, digitiform process; ml, median lobe; sg, seminal groove orifice. Scales: 10 μm (Fig. 7), 20 μm (Figs 8, 12), 100 μm (Figs 9–11, 13).

FIGURES 14–15. Nepalella brevichaeta sp. nov., male holotype (ZMUM). 14. Posterior gonopods, caudal view. 15. Anterior and posterior gonopods, frontal view. Abbreviations: a, angiocoxite; ag, anterior gonopods; ap, angiocoxal projection; b, hairlike structure; bl, anterior colpocoxital blade; bo, boat-shaped outgrowth; cxi, coxite. Scales: 1.0 mm (Fig. 14), 0.5 mm (Fig. 15).