Plusioglyphiulus samakkee, 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 : 50-56

Plusioglyphiulus samakkee sp. n. Figs 45−47 .

Material examined: Holotype male ( MNHN GA 073 ), Thailand, Ratchaburi Prov., Cave Tham Kwa Bin (= Khao

Bin), guano, Berlese extraction, 1 August 1987, leg. L. Deharveng (THA-RCI-002). Paratype: 2 juveniles ( MNHN GA 073 ), 1 female ( SEM), same locality, together with holotype .

Name: To emphasize “samakkee”, in Thai meaning “harmony”, a noun in apposition.

Diagnosis: Differs from congeners in the oligotrichous gnathochilarium, coupled with the particular carinotaxy patterns, and the special shapes and armature of both gonopod pairs, in particular due to the retention of telopodite remnants in the posterior gonopods (see also Key below).

Description: Coloration of holotype uniformly light marbled grey-brown; head, antennae, collum, venter and legs light yellowish to pallid; metatergal crests and, especially, poriferous tubercles infuscate, brown. Coloration of juveniles uniformly yellowish to pallid.

Length of holotype about 27 mm, width 1.1 mm, with 52p+2a+T. Collum and segments in posterior third of body equally broadest.

All characters as in P. panhai sp. n. ( Figs 45F , 46A,C, D, G , 47A, E, F ), except as follows. Ocellaria small, dark brown to blackish, ovoid in shape, in holotype with about nine visible ocelli arranged in 4–5 longitudinal rows. Gnathochilarium ( Figs 46E , 47B ) oligotrichous (n=2).

Postcollum constriction very evident, due to especially enlarged collum and segment 2 ( Figs 45A, D , 46B ). Carinotaxy formula of collum: /(t)/(t)+1p/t+/t/t+2p/t+3ap/(t)/(t)+4p/t/t+ pp/t/t+/ma/m ( Figs 45A, D, E ). 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 45A–C , 46F ); all crests and tubercles, including poriferous cones, rather low. Midbody segments ovoid in cross-section, slightly compressed laterally ( Fig. 46F ).

Male legs 1 with a usual strong central hook curved forward, appendages large, sac-shaped, densely setose, 1- segmented ( Fig. 47C ). Male legs 2 strongly enlarged, penes bare ( Fig. 47D ).

Anterior gonopods rather simple, with a paramedian pair of anterior coxosternal processes (cxp1) rather high, slen- der, largely subcontiguous, suberect, parabasally carrying several, strong, lateral setae; caudal pair of coxosternal processes (cxp2) only slightly higher, also suberect, each supplied with a sharp, lateral, terminal tooth on caudal face; telopodites (te) finger-shaped, long, apically setose, about as high as cxp1, attached to coxal region caudolaterally, probably capable of movement ( Figs 47G, H ). Posterior gonopods about as high, rather complex, coxites well separated from sternum, fused only basally, membranous and sac-shaped; each coxite mainly consisting of a stalk surmounted by a large fovea, a distinct axe-shaped lobe and a high flagellum; telopodites (te) coniform, rather small, located laterally at about midway of coxites ( Fig. 47I ).

Plusioglyphiulus bessoni Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 Plusioglyphiulus bessoni Golovatch et al. 2009: 86 , figs 11–13. Figs 48−50 .

Material examined: 1 male, 1 female ( MNHN GA 057 ) , 1 female ( SEM), Thailand, Nan Prov., Pha Singha Distr., Pha Tub Cave Forest Park, Cave Tham Pha Tub , guano, hand collection, 9 June 1989, leg. L. Deharveng (THA- NAN-003) .

Brief redescription: Coloration uniformly grey-brown; head, collum, venter and legs light yellowish to pallid; metatergal crests and, especially, poriferous tubercles infuscate, dark brown to blackish.

Length of male about 30 mm, width 1.5 mm, with 52p+5a+T. Length of female about 35 mm, width 1.8 mm, with 62p+3a+T. Collum broadest.

All characters as in P. panhai sp. n. ( Figs 48E , 49B, E, F , 50A, D, E ), except as follows. Ocellaria large, brownblackish, ovoid in shape, with about 10–13 visible ocelli arranged in 5–6 longitudinal rows. Gnathochilarium ( Figs 49A , 50B ) rather oligotrichous (n=2).

Postcollum constriction very evident, due to especially enlarged collum and segment 2 ( Figs 48A, D ). Carinotaxy formula of collum: 1p/t+2p/t+3p/(t)/t+/t/t+4p/(t)/t+/t/t+pp/t/t+/ma/m ( Figs 48A, D ). Carinotaxy of metaterga 2 and 3, 8/8+m/m+8/8, that of metatergum 4, 7/7+m/m+7/7; usual formula of all following metaterga until about posterior third of body, 3/3+I/i+3/3/3+m/m/m, thereafter, 4/4+I/i+3/3/3+m/m/m ( Figs 48A–C , 49D ); all crests and tubercles, including poriferous cones, rather low. Midbody segments ovoid in cross-section, slightly compressed laterally ( Fig. 49D ). Epiproct dorsally with several tubercles arranged in about three transverse rows, caudal margin evidently emarginate ( Figs 48C, F , 49C ).

Male legs 1 with a usual strong central hook curved forward, appendages large, sac-shaped, poorly setose, 1- segmented. Male legs 2 strongly enlarged, penes bare ( Fig. 50C ).

Anterior gonopods rather simple, with a paramedian pair of anterior coxosternal processes (cxp1) relatively low, slender, only parabasally contiguous, slightly curved, apically pointed; caudal pair of coxosternal processes (cxp2) higher, also slightly curved, each narrowly rounded and supplied with a sharp subterminal tooth on front face; telopodites (te) digitiform, long, apically setose, slightly shorter than cxp2, attached to coxal region caudolaterally, probably capable of movement ( Fig. 50F ). Posterior gonopods only slightly shorter, rather simple, coxites well separated from sternum, fused only basally, contiguous to about midway, membranous; at about midlength each coxite consisting of a short, finely fringed, frontomedian, subquadrate lobe with a setoid filament at base; a small, caudolateral, finely denticulate ledge; and main, far higher, central piece surmounted by a large fovea and a distinct flagellum; evident telopodites missing ( Fig. 50G ).

Remarks: The new samples allow for a better idea to be obtained of the range of individual variation observed in several features of this species. Thus, the shape and armament of the epiproct appears to vary clearly from being regularly rounded at a prominent caudal margin and carrying only 1+1 dorsal tubercles, as noted for the type series, to emarginate caudally and supplied with several tubercles dorsally, as seen in new material. Apparently, this character must be applied to Plusioglyphiulus systematics only with caution, forcing us to omit it from the Key below.

Slight variation also concerns the carinotaxy patterns of the collum and, to a lesser degree, of the following segments ( Golovatch et al. 2009), but generally these characters are stable enough to make the species easily recognizable.

It is the structure of the gonopods ( Figs 50 F, G ) that leaves no doubts as regards the identity of this species, variations being negligible ( Golovatch et al. 2009).

The above redescription is also deemed helpful in more easily recognizing and keying all of the Thai species of Plusioglyphiulus we currently know.

Plusioglyphiulus ampullifer Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 Plusioglyphiulus ampullifer Golovatch et al. 2009: 79 , figs 4–7. Figs 51 and 52 .

Material examined: 1 male ( ZMUM) , 1 male ( SEM), Vietnam, Dong Nai Prov., Cat Tien National Park , seasonal tropical forest, soil samples, 1 June 2005 . 2 females ( ZMUM), same locality, 15 July 2005 ; 1 male ( ZMUM), same locality, 8–23 November 2005 , all leg. A. Anichkin.

Remarks: This species has only recently been described from the same province in southern Vietnam ( Golovatch et al. 2009). The new samples, taken epigeically from a patch of seasonal tropical forest only less than 40 airkm away from the type locality, agree in every detail with type material, this being well documented with new illustrations ( Figs 51 and 52 ).

Figures

FIGURE 45. Plusioglyphiulus samakkee sp. n., female 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: same, front view. F: midbody segments, dorsal view. Scale bars: A, B, D and F, 0.5 mm; C and E, 0.2 mm.

FIGURE 46. Plusioglyphiulus samakkee sp. n., female paratype. A: posterior part of body, dorsal view. B: anterior part of body, ventral view. C: midbody segments, ventral view. D: posterior part of body, ventral view. E: gnathochilarium, ventral view. F: cross-section of a midbody segment, caudal view. G: enlarged claw, sublateral view. Scale bars: A, C–E, 0.2 mm; B and F, 0.5 mm; G, 0.02 mm.

FIGURE 47. Plusioglyphiulus samakkee sp. n., holotype. A: antenna, lateral view. B: gnathochilarium, ventral view. C: leg 1, sublateral view. D: leg 2, caudal view. E: leg 3, caudal view. F: midbody leg, lateral view. G: anterior gonopods, caudolateral view. H: right anterior gonopod, mesal view. I: posterior gonopods, front view. te: telopodite; cxp1: anterior coxosternal process; cxp2: posterior coxosternal process. Scale bar: A–F, 0.4 mm; G–I, 0.2 mm.

FIGURE 48. Plusioglyphiulus bessoni Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009, female topotype. 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–E, 0.5 mm; F, 0.2 mm.

FIGURE 49. Plusioglyphiulus bessoni Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009, female topotype. A: gnathochilarium, ventral view. B: midbody segments, ventral view. C: posterior part of body, ventral view. D: cross-section of a midbody segment, caudal view. E: midbody leg, lateral view. F: enlarged claw, lateral view. Scale bars: A and C, 0.2 mm; B and D, 0.5 mm; E, 0.1 mm; F, 0.01 mm.

FIGURE 50. Plusioglyphiulus bessoni Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009, male topotype. A: antenna, lateral view. B: gnathochilarium, ventral view. C: leg 2, caudal view. D: leg 3, caudal view. E: midbody leg, lateral view. F: anterior gonopods, front view. G: posterior gonopods, caudal view. te: telopodite; cxp1: anterior coxosternal process; cxp2: posterior coxosternal process. Scale bar: A–E, 0.4 mm; F and G, 0.2 mm.

FIGURE 51. Plusioglyphiulus ampullifer Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009, male from Cat Tien. 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. G: anterior part of body, ventral view. H: posterior part of body, ventral view. I: gnathochilarium, ventral view. J: cross-section of a midbody segment, caudal view. K: enlarged ozopore region, lateral view. L: leg 1, lateral view. M: leg 2, caudal view. Scale bars: A–E, G and J, 0.5 mm; F, H, I and M, 0.2 mm; K and L, 0.1 mm.

FIGURE 52. Plusioglyphiulus ampullifer Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009, male from Cat Tien. A: segment 3 with legs 3, front view. B: midbody leg, lateral view. C: enlarged claw, lateral view. D: ventral parts of segments 6 and 7, ventrolateral view. E: cross-section of segment 7, caudal view. F: both gonopod pairs, ventral view. G: same, caudal view. H: same, front view. Scale bars: A and E, 0.5 mm; B, D and F–H, 0.1 mm; C, 0.02 mm.