Eutrichodesmus troglobius 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 : 20-22

Taxon classification Animalia Polydesmida Haplodesmidae

Eutrichodesmus troglobius Golovatch, Geoffroy, Mauries & VandenSpiegel sp. n. Figs 20, 21

Type material.

Holotype ♂ (MNHN JC 375), China, Guizhou Prov., Kaiyang, Cave Xianyan Dong, 19.II.2004, leg. S. Prevorčnik & B. Sket.

Paratypes: 1 ♂, 2 ♀, 2 subadult ♀ (MNHN JC 375), 1 ♀ (SEM), same data, together with holotype.

Name.

To emphasize cavernicoly; adjective.

Diagnosis.

Differs from congeners by the relatively broad and modestly declivous paraterga which are set low on the body at about 45° to the vertical axis and distinctly discontinue the more strongly declined outline of the sides above paraterga, coupled with low, but distinct, mostly longitudinally oblong, metatergal tuberculations arranged in three transverse irregular rows, and the rather simple gonopod acropodite which only shows a small distodorsal tooth (see also Key below).

Description.

Length of adults ca 8-9 mm, width 1.0 and 1.9-2.0 mm on midbody pro- and metazonae, respectively. Holotype ca 9 mm long, 1.0 and 2.0 mm wide on pro- and metazonae, respectiverly. 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 incomplete because of broad and modestly declivous paraterga. Antennae rather long and poorly clavate (Fig. 20H, L). Collum not covering the head from above, fore margin clearly lobulate and slightly elevated, with abundant distinct tuberculations arranged in regular rows, but lobulations observed only at anterior margin. Metaterga behind collum with three transverse, rather irregular, mixostictic rows of similarly distinct, longitudinally oblong, setigerous tuberculations extending onto paraterga, usually about 8-10+8-10 per row (Fig. 20 A–F); mid-dorsal regions of metaterga not elevated; caudomarginal lobulations numerous, 2-3 more evident ones only on paraterga (Fig. 20 A–F); limbus microcrenulate (Fig. 20M). Paraterga with evident shoulders anteriorly, broad, modestly declivous, directed ventrolaterad at about 45° to even more strongly declined sides above paraterga (Fig. 20N), tips lying clearly below level of venter, usually distinctly trilobate laterally; anterolaterals evident only in segment 2 (Fig. 20A, D). Paraterga 2 strongly enlarged, directed ventrad (Fig. 20A, D, H), lateral margin broadly rounded, with few, but very distinct lobulations; a full row of similarly large caudolaterals located above schism, both schism and hyposchism being small (Fig. 20A). Tergal setae short, 2-segmented, apical part setoid (Fig. 20G). Pore formula apparently normal, ozopores indistinct. Epiproct strongly flattened dorsoventrally and tuberculate dorsally (Fig. 20C, F, J). Hypoproct subtrapeziform (Fig. 20J).

Sterna usually with a rather deep, narrow depression between coxae (Fig. 20I, J). Legs long and slender, 1.1-1.2 times as long as body height (Fig. 20I, J, N), only coxae and most surface of prefemora finely micropapillate (Fig. 21A).

Gonopods (Fig. 21B, C) rather simple. Coxae subquadrate, large, micropapillate and setose mostly on lateral face, with a small, subtriangular, setigerous tooth caudola terally. Telopodite considerably longer than coxite, moderately and regularly curved ventrad, setose nearly over its basal half until base of a prominent, curved, subspiniform, abundantly microtuberculate, distofemoral process (dp), the latter situated at about basal 1/3 of telopodite, acropodite twisted, with a small, subapical, ventral tooth (d); seminal groove terminating subapically; a hairpad wanting.