Plusioglyphiulus pimvichaiae, Golovatch & Geoffroy & Mauriès & Vandenspiegel, 2011

Golovatch, Sergei I., Geoffroy, Jean-Jacques, Mauriès, Jean-Paul & Vandenspiegel, Didier, 2011, The millipede genus Plusioglyphiulus Silvestri, 1923 in Thailand (Diplopoda, Spirostreptida, Cambalopsidae) 2940, Zootaxa 2940 (1), pp. 1-63 : 20-22

Plusioglyphiulus pimvichaiae sp. n. Figs 16−19 .

Material examined: Holotype male ( MNHN GA 074 ), Thailand, Cha Nai Prov., Tak Fa Distr., Wat Khuhasophon , Cave Tham Prasawan , 100 m a.s.l., 1 December 2009, leg. C. Sucharit and members of the Animal Systematics Research Unit . Paratypes: 6 males, 11 females ( MNHN GA 074 ) , 1 male, 1 female ( ZMUM) , 1 male, 1 female ( ZMUC) , 1 male, 1 female ( MZCU) , 1 male, 1 female ( NMNHS) , 1 male ( SEM) , same locality, together with holotype .

Name: Honours Miss Piyatida Pimvichai, also one of the collectors, our colleague myriapodologist and another active member of the Animal Systematics Research Unit at Chulalongkorn University, Bangkok, Thailand.

Diagnosis: Differs from congeners in the oligotrichous gnathochilarium, coupled with the particular carinotaxy patterns, and the special shapes and armature of both gonopod pairs, especially the long and simple flagellum crowning each posterior gonopod (see also Key below).

Description: Length 16–28 mm, width 0.9–1.1 mm, collum and midbody segments being equally broadest. Coloration uniformly dark grey-brown to light yellow-brown; antennae and collum often lighter, usually yellowbrown; metatergal crests and, especially, poriferous tubercles often infuscate.

Body with 44–57p+4–1a+T. Length of holotype about 28 mm, width 1.1 mm, with 57p+3a+T.

All characters as in P. panhai sp. n. ( Figs 16B, C, E, F , 17A, C, D, F , 18B , 19A, E ), except as follows. Ocellaria large, blackish, ovoid in shape, with about 14–23 ocelli arranged in 5–6 longitudinal rows. Gnathochilarium ( Figs 17B , 19B ) rather oligotrichous, with a separate promentum (n=2).

Postcollum constriction very evident, due to especially enlarged collum and segment 2 ( Figs 16A, D ). Carinotaxy formula of collum: /(t)/t+/(t)/(t)+1p/t+2p/t+3p/t+/t/t/t+4p/(t)/(t)+/t/t+pp/t/t+/ma/m ( Figs 16A, D ). Carinotaxy of metaterga 2–4, 7/7+m/m+7/7; usual formula of following metaterga until about caudal third of body, 3/3+I/i+3/ 3/3+m/m, thereafter, 4/4+I/i+3/3/3+m/m ( Figs 16A–C , 17E ); all crests and tubercles, including poriferous cones, rather low. Midbody segments ovoid in cross-section, slightly compressed laterally ( Fig. 17E ).

Male legs 1 ( Figs 18A , 19C ) with a usual strong central hook curved forward, appendages larger, sac-shaped, densely setose, 1-segmented. Male legs 2 strongly enlarged ( Figs 18A , 19D ).

Anterior gonopods rather complex, with a paramedian pair of anterior coxosternal processes (cxp1), high, slen- der, only apically densely setose and slightly caudad curved, nearly contiguous and digitiform; pair of posterior coxosternal processes (cxp2) still higher, distally torsate, lobiform and pointed; telopodites (te) club-shaped, densely setose distally, slightly shorter than cxp2, attached to coxal region caudolaterally, probably capable of movement ( Figs 18C, D , 19F ). Posterior gonopods somewhat longer, rather simple, coxites well separated from sternum, fused only basally, sac-shaped, membranous, each surmounted by an evident fovea with a long, simple, gradually attenuating flagellum medially; telopodites virtually missing ( Figs 18E, F , 19G ).

Figures

FIGURE 16. Plusioglyphiulus pimvichaiae sp. n., male paratype. A: anterior part of body, lateral view. B: midbody segments, lateral view. C: posterior part of body, lateral view. D: anterior part of body, dorsal view. E: midbody segments, dorsal view. F: posterior part of body, dorsal view. Scale bars: A–C, E and F, 0.2 mm; D, 0.5 mm.

FIGURE 17. Plusioglyphiulus pimvichaiae sp. n., male paratype. A: anterior part of body, frontoventral view. B: gnathochilarium, ventral view. C: midbody segments, ventral view. D: posterior part of body, ventral view. E: cross-section of a midbody segment, caudal view; F: enlarged ozopore region, lateral view. Scale bars: A, 0.5 mm; B–E, 0.2 mm; F, 0.1 mm.

FIGURE 18. Plusioglyphiulus pimvichaiae sp. n., male paratype. A: legs 1–3, caudal view. B: enlarged claw, dorsolateral view. C: anterior gonopods, front view. D: same, caudal view. E: posterior gonopods, caudal view. F: same, ventrocaudal view. Scale bars: A, 0.1 mm; B, 0.01 mm; C−F, 0.05 mm.

FIGURE 19. Plusioglyphiulus pimvichaiae sp. n., male paratype. A: antenna, lateral view. B: gnathochilarium, ventral view. C: leg 1, subfront view. D: leg 2, caudal view. E: leg 3, front view. F: anterior gonopods, caudolateral view. G: posterior gonopods, subcaudal view. te: telopodite; cxp1: anterior coxosternal process; cxp2: posterior coxosternal process. Scale bar: A–E, 0.4 mm; F and G, 0.2 mm.