Plusioglyphiulus jaydee, 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 : 40-43

Plusioglyphiulus jaydee sp. n. Figs 36−38 .

Material examined: Holotype male ( MNHN GA 070 ), Thailand, Kanchanaburi Prov., Sai Yok Distr., Ban Nam Tok, Cave Tham Rawa , hand collection, 16 June 1986, leg. P. Leclerc (THA-KAN-039) . Paratype: 1 male ( MNHN GA 070 ) , 1 female ( SEM), same locality, together with holotype .

Name: To emphasize “jaydee”, in Thai meaning “stupa, pagoda or chedi”, a noun in apposition to reflect the normally strongly bulging collum in Plusioglyphiulus .

Diagnosis: Differs from congeners in the oligotrichous gnathochilarium showing only a weak border between the pro- and eumentum, coupled with the presence of 2+2 dorsal tubercles on the epiproct, the particular carinotaxy patterns, and the special shapes and armature of both gonopod pairs (see also Key below).

Description: Collum and segments in posterior third of body equally broadest. Coloration uniformly yellowbrown; head, antennae, collum, venter and legs light yellowish; metatergal crests and, especially, poriferous tubercles only slightly infuscate, brown.

Length of holotype about 22 mm, width 1.1 mm, with 52p+3a+T. Length of male paratype about 21 mm, width 1.1 mm, with 47p+3a+T.

All characters as in P. panhai sp. n. ( Figs 36D, F , 37B, C, F , 38D ), except as follows. Ocellaria small, brownish, obviously partly faded at peripheries, ovoid in shape, with about 12–14 visible ocelli arranged in 4–5 longitudinal rows. Gnathochilarium ( Fig. 38A ) rather oligotrichous, with an indistinctly separated promentum (n=1).

Postcollum constriction very evident, due to especially enlarged collum and segment 2 ( Figs 36A, C , 37A ). Carinotaxy formula of collum: /(t)/(t)+/(t)/+1p/t+/(t)/(t)+2p/t+3p/t/t+/t/t+pp/t/t+/ma/m ( Figs 36A, C ). Carinotaxy of metaterga 2–4, 7/7+m/m+7/7; usual formula of all following metaterga, 3/3+I/i+3/3/3+m/m/m ( Figs 36A, B , 37E ); all crests and tubercles, including poriferous cones, rather low. Midbody segments ovoid in cross-section, slightly compressed laterally ( Fig. 37E ). Epiproct dorsally with 2+2 tubercles arranged in a transverse row ( Figs 36E , 37D ).

Male legs 1 ( Fig. 38B ) with a usual strong central hook curved forward, appendages rather small, sac-shaped, poorly setose, 2-segmented. Male legs 2 strongly enlarged, penes bare ( Fig. 38C ).

Anterior gonopods rather simple, with a paramedian pair of anterior coxosternal processes (cxp1), relatively low, rather slender, contiguous, laterally sparsely setose, apically narrowly rounded; caudal pair of coxosternal processes (cxp2) higher, twisted, unciform, pointed; telopodites (te) club-shaped, setose apically, considerably shorter than cxp2, attached to coxal region caudolaterally, probably capable of movement ( Fig. 38E ). Posterior gonopods considerably shorter, rather simple, coxites well separated from sternum, fused only basally, sac-shaped, membranous, each surmounted by a large fovea supplied with a short, but evident flagellum on top; telopodites missing ( Figs 38F, G ).

Remarks: The unusually feeble border-line between the pro- and eumentum observed in the single dissected sample so vividly reminds us of several such cases in Glyphiulus species that it forces us to use this trait with caution as a species-specific character in Plusioglyphiulus as well. It has thus been omitted from the Key below.

Figures

FIGURE 36. Plusioglyphiulus jaydee sp. n., female paratype. A: anterior part of body, lateral view. B: posterior part of body, lateral view. C: anterior part of body, dorsal view. D: midbody segments, dorsal view. E: posterior part of body, dorsal view. F: enlarged texture of midbody segments, lateral view. Scale bars: A, B and D, 0.5 mm; C and E, 0.2 mm; F, 0.1 mm.

FIGURE 37. Plusioglyphiulus jaydee sp. n., female paratype. A: anterior part of body, ventral view. B: midbody segments, ventral view. C: posterior part of body, ventral view. D: same, caudal view. E: cross-section of a midbody segment, caudal view. F: enlarged distal part of antenna, sublateral view. Scale bars: A, B and E, 0.5 mm; C and D, 0.2 mm; F, 0.1 mm.

FIGURE 38. Plusioglyphiulus jaydee sp. n., male paratype. A: gnathochilarium, ventral view. B: leg 1, caudal view. C: leg 2, caudal view. D: leg 3, front view. E: anterior gonopods, front view. F: posterior gonopods, front view. G: same, caudal view. te: telopodite; cxp1: anterior coxosternal process; cxp2: posterior coxosternal process. Scale bar: A–D, 0.4 mm; E–G, 0.2 mm.