Eutrichodesmus deporatus Liu & Wesener

Liu, Weixin, Golovatch, Sergei & Wesener, Thomas, 2017, Four new species of the millipede genus Eutrichodesmus Silvestri, 1910 from Laos, including two with reduced ozopores (Diplopoda, Polydesmida, Haplodesmidae), ZooKeys 660, pp. 43-65 : 46-47

Eutrichodesmus deporatus Liu & Wesener sp. n. Figs 1B, 5, 6, 7

Material examined.

Holotype male (SMF), Laos, Luang Prabang Prov., NE Luang Prabang, Nam Ou, Nong Khiao, Cave Tham Pathok, hand collected, N20°33.082', E102°37.925', 373 m, 11.III.2006, coll. P. Jäger & J. Altmann.

Paratypes.

1 male, 1 female (ZFMK MYR6128 & 6129), same data as holotype; 2 females, 3 juveniles (SMF), same data as holotype; 1 male (SMF), same locality, 29.II.2008, coll. P. Jäger.

Etymology.

To emphasize the ozopores in this species being mostly reduced; adjective.

Diagnosis.

Differs from all other species of the genus in the ozopores retained only on body segment 17, coupled with the gonopod acropodite showing a slightly bifid dorsolateral tooth subapically. See also Key above.

Description.

Length of adults of both sexes ca. 7.5-8.0 mm, width 0.6-0.8 mm and 1.6-1.8 mm on midbody pro- and metazona, respectively.

Coloration uniformly pallid (Fig. 1B).

Adults with 20 segments (Fig. 1B), body conglobation complete.

Antennae short, but slender (Figs 1B, 5A); in length, antennomere 6> 3 = 2> 4 = 5> 7> 1.

Labrum with three teeth (Fig. 5A).

Head (Fig. 5A), bacilliform sensilla on antennae (Fig. 6A), gnathochilarium (Fig. 6D), mandibles (Fig. 6B), prozona (Fig. 5E), endoterga, metatergal setae (Fig. 6H), sterna (Fig. 6E), pleurosternal keels, stigmata (Fig. 6 I–J), legs (Fig. 6K), gonopod aperture, telson (Fig. 5 I–J), and vulvae (Fig. 6K) all similar to Eutrichodesmus steineri sp. n.

Collum subtrapeziform, with five transverse rows of round microvillose tubercles, flattened medially (Fig. 5D). Fore margin with two distinct tubercles on each side (Fig. 5D).

Stricture between pro- and metazona broad and shallow, finely microgranulate (Fig. 5E). Limbus with relatively long crenulations and nearby abundant microvilli (Fig. 6F).

Metaterga 2-5 with three transverse mixostictic rows of similarly microvillose tubercles, flattened medially, about 7 + 7 per row (Fig. 5 B–D). Three transverse rows of rather small, flat tuberculations on metaterga 6-19 (Fig. 5 F–H). Metaterga 5-19 each with a very high, large, bifid, mid-dorsal projection (Fig. 5B, F–H). Projections 5-17 upright, then directed slightly caudad on matetaga 18 and 19 (Fig. 5F).

Front margin of paraterga 2-4 strongly elevated (Fig. 5 B–D). Paraterga 2 strongly enlarged, vaguely trilobate laterally, with four frontal and three caudal evident lobulations (Fig. 5D); paraterga 3 and 4 slightly shorter than others, bilobate laterally (Fig. 5 B–C); following paraterga laterally 3- or 4-lobulated, caudolaterally at base with two distinct lobulations (Figs 5F, H, 6C).

Ozopores mostly reduced, only visible on paraterga 17 (Fig. 6G).

Gonopods (Figs 6 M–N, 7) simple. Coxae abundantly micropapillate and sparsely setose ventrolaterally, with an apicolateral lobe (cl). Telopodite longer than coxite, slender throughout, setose in basal half, with a prominent, digitiform, lateral, distofemoral process (dp) at about midway. Acropodite with a micropapillate process (pp) at base and a dorsolateral tooth (t1) subapically, tip slightly bifid; seminal groove terminating in a hairpad at a small triangular tooth (t2) subapically.

Remarks.

The specimens come from the Cave Tham Pathok which is about 100 meters long, and the temperature inside is about 15 °C. The animals were found living at a small waterfall at a distance of 20 meters from the entrance. In addition, Heteropoda spp. ( Arachnida) and Glyphiulus sp. ( Diplopoda, Cambalopsidae ) were found in the cave ( Steinmetz 2007).

The pallid body and long legs suggest that Eutrichodesmus deporatus sp. n. is most likely a troglobite.