Eutrichodesmus filisetiger 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 : 16-21

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

urn:lsid:zoobank.org:act:CC34CE29-FD03-4796-B19E-8EFD94686705

Figs 12-15

Type material: Vietnam, Thanh Hoa Prov., Thanh Son: Lang Kho Muong, Hang Doi Cave , hand collected, 13.XII.2003, leg. L. Deharveng and team (Vn0312-27), holotype ♁ (MNHN JC 320), paratypes: 1 ♁, 2 subad. (MNHN JC 320), 1 ♁ (SEM) . Vietnam, Thanh Hoa Prov., Lang Hang: Hang Bo Muoi Cave , hand collected, 14.XII.2003, leg. L. Deharveng and team (Vn0312-33), paratype ♀ (ZMUM) .

Name: To emphasize the peculiar, filiform but rather short tergal setae.

Diagnosis: Differs from congeners by the perfect volvation, coupled with the filiform tergal setae, evident metatergal lobulations, a regular pattern of tergal tuberculation and a few minor details of gonopod structure (in particular, the shape of the telopodite and a rudimentary distofemoral process).

Description: Length of adults of both sexes ca 12-13 mm, width 2.5–2.6 mm, body broadest at segment 3 or 4. Holotype ca 12 mm long and 2.5 mm wide. Coloration uniformly pallid, shown pinkish because of a photographic artifact (Fig. 12).

Adults with 20 segments (Figs 12, 13A), pattern of conglobation typical of “doratodesmids”. Head, antennae (Fig. 14A), tegument (Figs 14E, F), sterna (Fig. 14C), gonopod aperture (Fig. 14G) and many other characters (Figs 14C, D) much as in E. distinctus sp. n.; collum rather irregularly tuberculate and slightly flattened medially at anterior edge (Figs 13E, 14B). Metaterga behind collum with three transverse, rather regular, mixostictic rows of rounded, flat, undifferentiated tubercles (Figs 13A-F), each crowned with a short, 2-segmented, filiform seta (often broken off) (Figs 14E, F). Only last two metaterga a little elevated compared to preceding ones (Figs 12, 13A, D). Paraterga directed ventrolaterad, nearly continuing general outline of convex dorsum, rather broad, slightly surpassing level of venter, most of them evidently lobulate (Figs 13A-F, 14C); paraterga 2 strongly enlarged, evidently lobulate only anterolaterally but not laterally (Fig. 13B). Following paraterga broadly rounded, evidently 4-lobate laterally and 3-lobate caudolaterally (Figs 13A-D, 14G). Limbus very distinctly spiculate, almost hidden by nearby abundant microvilli (Fig. 14E). Pore formula normal, ozopores very poorly visible, located dorsally near base of ventrocaudal lobulation (Figs 13C, D). Epiproct short, with regular tuberculations (Fig. 13D).

Legs relatively long and slender, slightly reaching edge of paraterga (Figs 14C, G).

Gonopods (Figs 14G, H, 15A-F) relatively complex. Coxae abundantly micropapillate and setose, with two conspicuous lobes: one normal, apicolateral, the other unusual, subtriangular, median, both apparently to control telopodite movements. Telopodite elongate, slender, slightly arcuate, with only a rudimentary distofemoral process at about midway (barely seen in lateral view as a short prong in a kind of pocket) and an evident hairpad at distal one-third of acropodite (= solenomere), also marking a branching point of two long, slender, apical pieces, one lateral, bifid, a little shorter and well-sclerotized, the other lamellar, pointed and dentate.

Remarks: This rather large, pallid species shows filiform tergal setae and only poorly differentiated metatergal tubercles. It is also a typical “doratodesmid”, possibly still another troglobite.

Figures

Figure 12. Eutrichodesmus filisetiger sp. n., ♁ paratype from Hang Doi Cave; habitus, lateral view. (Photographed not to scale by L. Deharveng).

Figure 13. Eutrichodesmus filisetiger sp. n., ♁ paratype from Hang Doi Cave; A, habitus, lateral view; B, E, anterior part of body, lateral and frontodorsal views, respectively; C, F, midbody segments, lateral and dorsal views, respectively; D, posterior part of body, lateral view. – Scale bars: A-F, 0.5 mm.

Figure 14. Eutrichodesmus filisetiger sp. n., ♁ paratype from Hang Doi Cave; A, head, dorsal view; B, collum, frontodorsal view; C, cross-section of a midbody segment, caudal view; D, posterior part of body, ventral view; E, texture of tegument, dorsal view; F, setae on collum; G, segments 6 and 7, ventral view; H, gonopods in situ. – Scale bars: A-D, G, 0.5 mm; E, F, H, 0.1 mm.

Figure 15. Eutrichodesmus filisetiger sp. n., ♁ paratypes from Hang Doi Cave; A-F, gonopod, subventral, ventral, sublateral, mesal, lateral and mesal views, respectively. – Scale bars: A-C, 0.01 mm; D, 0.05 mm; E, F, 0.2 mm.

Figure 2. Eutrichodesmus distinctus sp. n., ♁ paratype; A, habitus, lateral view; B, E, anterior part of body, lateral and dorsal views, respectively; C, F, midbody segments, lateral and dorsal views, respectively; D, G, posterior part of body, lateral and dorsal views, respectively. – Scale bars: A, 0.5 mm; B-G, 0.2 mm.

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 4. Eutrichodesmus regularis sp. n., ♁ paratype; habitus, lateral view. (Photographed not to scale by L. Deharveng).

Figure 16. Eutrichodesmus curticornis sp. n., ♀ paratype; habitus, lateral view. (Photographed not to scale by L. Deharveng).

Figure 5. Eutrichodesmus regularis sp. n., ♁ paratype; A, habitus, lateral view; B, E, anterior part of body, frontodorsal and ventral views, respectively; C, midbody segments, dorsal view; D, F, posterior part of body, dorsal and ventral views, respectively. – Scale bars: A, C, 0.5 mm; B, D-F, 0.2 mm.