Eutrichodesmus reductus Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009

Golovatch, Sergei, Geoffroy, Jean-Jacques, Mauriès, Jean-Paul & VandenSpiegel, Didier, 2009, Review of the millipede genus Eutrichodesmus Silvestri, 1910 (Diplopoda, Polydesmida, Haplodesmidae), with descriptions of new species, ZooKeys 12 (12), pp. 1-46 : 37-40

Eutrichodesmus reductus Golovatch, Geoffroy, Mauriès & VandenSpiegel , sp. n.

urn:lsid:zoobank.org:act:1726A727-8FC2-4BF8-807D-8DFC1C54380C

Figs 31-33

Type material: Indonesia, Sulawesi Selatan, kab. Maros: Samanggi, Gua Saripa Cave , hand collected, 18.VIII.1990, leg. A. Bedos and L. Deharveng (SULS-214), holotype ♁ (MZB), paratypes: 1 ♁ (MNHN JC 325), 1 ♀ (SEM) .

Name: To emphasize the strongly underdeveloped paraterga 2 and lack of metatergal tuberculation.

Diagnosis: Differs from congeners except E. communicans Golovatch, Geoffroy, Mauriès & VandenSpiegel, 2009 by the strongly underdeveloped paraterga 2, coupled

with 19 body segments and the absence of metatergal tuberculation; from E. communicans by a very short tergal trichome, from it and other congeners in a few minor details of gonopod structure (in particular, the shape of the telopodite).

Description: Length of adults of both sexes ca 4.0- 4.2 mm, width 0.45-0.5 mm, body broadest at midbody segments. Holotype ca 4.0 mm long and 0.45 mm wide. Coloration uniformly pallid, shown pinkish because of a photographic artifact (Fig. 31).

Adults with 19 segments, body subcylindrical (Figs 31, 32A), volvation apparently incomplete due to insufficiently wide and low paraterga. Head ( Fig. 33A ) slightly transverse, with a poorly separated pair of very low, paramedian tubercles above antennal sockets; antennae relatively short and clavate, antennomere 6 longest; tegument ( Figs 33 C-E) and many other characters ( Figs 32F , 33B ) much as in E. distinctus sp. n.; collum and following metaterga devoid of tuberculation, beset with numerous, irregularly arranged, extremely short setae ( Fig. 32 B-F, 33C-E). Paraterga directed ventrolaterad, slightly interrupting contour of convex dorsum, short, not reaching level of venter ( Figs 32 A-D); paraterga 2 ( Fig. 32B ) only a little enlarged compared to following ones, indistinctly lobulate both anterolaterally and laterally, with only a single noticeable lobe forming a schism ledge, both schism and hyposchism very small; paraterga 3 and 4 not narrower than others, overlap typical already from paraterga 4, not paraterga 5 as in preceding congeners. Paraterga broadly rounded caudally, very indistinctly lobulate laterally and with a single evident lobulation caudolaterally ( Figs 32 C-E, 33C). Limbus distinctly denticulate, almost hidden by nearby abundant microvilli ( Fig. 33D, E ). Pore formula normal, ozopores located dorsally near base of caudal corner of paraterga ( Fig. 33C ).

Legs relatively long and slender, evidently surpassing edge of paraterga ( Fig. 33B ).

Gonopods ( Fig. 33F, G ) relatively complex. Coxae abundantly micropapillate, but only with a few macrosetae. Telopodite elongate, only slightly arcuate, with a large, papillate, peculiar, distofemoral outgrowth (dp) in distal one-third and a slender but short solenomere bearing a few small setae (but no pad!) subapically at base of a very complex tip represented by two erect teeth, a longer uncus and a group of minute outgrowths.

Remarks: This small-bodied, pallid, non-volvatory (= “haplodesmid”, see Golovatch et al. 2009) species seems to be especially close, morphologically as well as geographically, to E. communicans from Vanuatu, Melanesia, southwestern Pacific ( Golovatch et al. 2009), possibly representing still one more troglobite.

Figures

Figure 3. Eutrichodesmus distinctus sp. n., ♁ paratypes; A, midbody segments, ventral view; B, telson, ventral view; C, anterior part of body, ventral view; D, texture of tegument, dorsal view; E, both gonopods in situ, ventral view; F-H, gonopod, ventral, mesal and lateral views, respectively. – Scale bars: A, 0.5 mm; B, E, G, 0.1 mm; C, H, 0.2 mm; D, 0.02 mm; F, 0.05 mm.

Figure 31. Eutrichodesmus reductus sp. n., ♁ and ♀ paratypes; habitus, lateral view. (Photographed not to scale by L. Deharveng).

Figure 32. Eutrichodesmus reductus sp. n., ♀ paratype; A, habitus, lateral view; B, anterior part of body, lateral view; C, midbody segments, lateral view; D-F, posterior part of body, lateral, dorsal and caudal views, respectively. – Scale bars: A, 0.5 mm; B-F, 0.1 mm.

Figure 33. Eutrichodesmus reductus sp. n., ♀ (A-E) & ♁ (F-G) paratypes; A, head, ventral view; B, midbody segments, ventral view; C, midbody paratergum with ozopore, dorsal view; D, E, texture of tegument, dorsal view; F, G, left gonopod, mesal and lateral views, respectively. – Scale bars: A, B, 0.1 mm; C, 0.02 mm; D, 0.05 mm, E, 0.01 mm; F, G, 0.1 mm.