Eutrichodesmus apicalis Golovatch, Geoffroy, Mauries & VandenSpiegel

Golovatch, Sergei I., Geoffroy, Jean-Jacques, Mauries, Jean-Paul & VandenSpiegel, Didier, 2015, Review of the millipede genus Eutrichodesmus Silvestri, 1910, in China, with descriptions of new cavernicolous species (Diplopoda, Polydesmida, Haplodesmidae), ZooKeys 505, pp. 1-34 : 17-19

Taxon classification Animalia Polydesmida Haplodesmidae

Eutrichodesmus apicalis Golovatch, Geoffroy, Mauries & VandenSpiegel sp. n. Figs 18, 19

Type material.

Holotype ♂ (MNHN JC 374), China, Hubei Prov., Yishang Yichang County, Grotte des Araignées, 15.VIII.1992, leg. J. Lips (K1-2).

Paratype: 1 ♂ (SEM), same data, together with holotype.

Name.

To emphasize the apical termination of the seminal groove; adjective.

Diagnosis.

Differs from congeners by the relatively narrow and strongly declivous paraterga which are set low on the body at about 40° to the vertical axis and distinctly discontinue the subvertical outline of the sides above paraterga, coupled with narrow paraterga which only slightly overreach the level of the venter, the low, but distinct, rounded, metatergal tuberculations arranged in three transverse irregular rows, and the rather complex gonopod (see also Key below).

Description.

Length of holotype ca 7 mm, width 0.6 and 1.0 mm on midbody pro- and metazonae, respectively. Coloration entirely pallid.

All characters as in Eutrichodesmus triangularis sp. n., except as follows.

Body with 20 segments (♂), conglobation pattern typical of “doratodesmoids”, volvation apparently being complete because of narrow and strongly declivous paraterga. Antennae rather short and clavate (Fig. 18G, J). Collum not covering the head from above, fore margin clearly lobulate and slightly elevated, with abundant, mostly distinct bosses or tuberculations arranged in regular rows of lobulations only at anterior and posterior margins. Metaterga behind collum with three transverse, rather irregular, mixostictic rows of similarly distinct, rounded, setigerous tuberculations extending onto paraterga, usually about 6-7+6-7 per row (Fig. 18 A–F); mid-dorsal regions of metaterga not elevated; caudomarginal lobulations few, usually evident only near bases of paraterga (Fig. 18 A–C); limbus microcrenulate (Fig. 18M). Paraterga with evident shoulders anteriorly, rather narrow, strongly declivous, directed ventrolaterad at about 40° to even more strongly declined, subvertical sides above paraterga (Fig. 18K), tips lying only slightly below level of venter, usually distinctly trilobate laterally; anterolaterals evident only in segment 2 (Fig. 18A, D). Paraterga 2 strongly enlarged, directed ventrad (Fig. 18A, D, G), lateral margin broadly rounded, with few, rather distinct lobulations; a full row of caudolaterals located above schism, both schism and hyposchism being small (Fig. 18A). Tergal setae short, apparently 2-segmented. Pore formula apparently normal, ozopores indistinct. Epiproct strongly flattened dorsoventrally (Fig. 18C, I). Hypoproct subtrapeziform (Fig. 18I).

Sterna usually with a rather deep, narrow depression between coxae (Fig. 18H). Legs rather short, but slender, nearly as long as body height (Fig. 18H, K), only coxae and most surface of prefemora finely micropapillate.

Gonopods (Figs 18N, O, 19) rather complex. Coxae subquadrate, large, micropapillate and setose on lateral face, with a small, truncate, setigerous tooth caudolater ally. Telopodite considerably longer than coxite, moderately curved ventrad, setose nearly over its basal half until base of a prominent, subspiniform, microtuberculate, subapically micropilose, distofemoral process (dp), the latter situated at about basal 1/3 of telopodite, acropodite twisted, with a small, midway, dorsomesal (x) and a stronger, subapical, ventral tooth (d), the latter located opposite a rounded lobe (z); tip subtruncate; seminal groove terminating apically; a hairpad wanting.

Remark.

More information on the location of the cave can be found at http://www.groupe-speleo-vulcain.com/explorations/expeditions-a-letranger/