Deharvengius, Golovatch, Sergei I., Geoffroy, Jean-Jacques & VandenSpiegel, Didier, 2014

Golovatch, Sergei I., Geoffroy, Jean-Jacques & VandenSpiegel, Didier, 2014, Review of the millipede family Trichopolydesmidae in the Oriental realm (Diplopoda, Polydesmida), with descriptions of new genera and species, ZooKeys 414, pp. 19-65 : 43-44

Deharvengius gen. n.

Diagnosis.

18 segments (♂, ♀); pore formula normal: 5, 7, 9, 10, 12, 13, 15-17; head modified in both sexes in being somewhat flattened dorsoventrally; paraterga very poorly developed, serrate/microdentate at lateral edge, with 3 rows of 2+2, long, simple setae (regardless of lateral setae); gonopod coxae with gonocoel not deep; telopodites clearly exposed, but lying tightly appressed and parallel to venter, strongly curved, semi-circular, unipartite, slender, directed mesad and strongly overlapping; prefemoral parts about half as long as telopodites, set off from acropodites neither by a sulcus nor a cingulum; acropodites with small solenophores (sph) lying basal to a spiniform, apical solenomere (sl). Seminal groove running mostly along ventral surface of subbasally obviously twisted acropodites.

Name.

To honour Louis Deharveng (MNHN), one of the principal collectors, masculine.

Type species.

Deharvengius bedosae sp. n., by present designation.

Remarks.

In having only 18 body segments, this new genus is almost unique amongst the Trichopolydesmoidea . The same segment counts seem to solely concern Moojenodesmus pumilus Schubart, 1944, only one of the species of the rather small Neotropical genus Moojenodesmus Schubart, 1945, from the same family Trichopolydesmidae ; Moojenodesmus pumilus is especially minute (<2.5 mm long), and it seems to be parthenogenetic and quite widespread in Brazil ( Golovatch 1992, 1994). Among the Oriental Trichopolydesmidae , partly globally as well, Deharvengius gen. n. stands well apart also in having a less convex head, only 2+2 tergal setae per row and very unusual gonopods. The latter are long, simple, unipartite, strongly curved and crossing medially, thus being quite similar to the condition observed in Cocacolaria (Fig. 2 B–E). Yet in Deharvengius gen. n. the gonopods are much more strongly appressed to the venter while the seminal groove runs mostly on the ventral = lateral (not mesal) side to terminate apically on a simple and slender (not at about midway on a stout and calyciform) solenomere. By its habitus and even gonopod structure, Deharvengius gen. n. resembles some Euro-Mediterranean genera of Trichopolydesmidae as well (see reviews by Mauriès (1983) and Golovatch et al. (2013)). Some of them show a deeply bipartite and strongly curved gonopod telopodite, the prefemoral part of which is quite elongate, but lies more or less transversely to strongly angular, largely (sub)parallel telopodites and extends across the nearly entire ventral width of segment 7. Such are Trichopolydesmus Verhoeff, 1898 (together with the subgenus Banatodesmus Tabacaru, 1980), Bacillidesmus Attems, 1898, Napocodesmus Ceuca, 1974 and Caucasodesmus Golovatch, 1985. In contrast, the gonotelopodites in Verhoeffodesmus Strasser, 1959, Cottodesmus Verhoeff, 1936 and Occitanocookia Mauriès, 1980 have increasingly shortened prefemoral parts, being enlarged and laterally flattened distad and unipartite, but mostly less strongly curved, in Cottodesmus and Occitanocookia also devoid of a solenomere, but sometimes supplied instead with what can be seen as a primordial accessory seminal chamber. In Trichopolydesmus , Heterocookia Silvestri, 1898, Ingurtidorgius Strasser, 1974 and, especially, Mastigonodesmus Silvestri, 1898, the solenomere is almost to fully flagelliform, branching off near the base of the femorite. In all these genera, the gonotelopodites are strongly exposed, not sunken inside an obvious gonocoel ( Golovatch et al. 2013).

Deharvengius gen. n. currently contains only one species.