Schizoturanius Verhoeff, 1931

Nefediev, Pavel S., 2022, Review of the genus Schizoturanius Verhoeff, 1931, with the description of a new species from the Altais, Asian Russia (Diplopoda: Polydesmida: Polydesmidae), Zootaxa 5174 (3), pp. 262-276 : 264

Genus Schizoturanius Verhoeff, 1931

Trachynotus Timotheew, 1897 .

Type species: T. dmitriewi Timotheew, 1897 , by monotypy. Preoccupied.

Schizoturanius Verhoeff, 1931 . Type species: Polydesmus strongylosomoides Attems, 1904 , by monotypy. First proposed as a subgenus of Turanodesmus Lohmander, 1933 ( Verhoeff 1931) , but a little later elevated to genus level ( Lohmander 1933).

Telopoditius Verhoeff, 1931 . Type species: Polydesmus melanchthonius Attems, 1927 , by monotypy. Proposed as a subgenus of Turanodesmus , synonymized with Schizoturanius by Lohmander (1933).

Turanodesmus Lohmander, 1933 (pro parte). Type species: Polydesmus almassyi Attems, 1904 , by subsequent designation of Lohmander (1933). Turanodesmus was first invalidly proposed for four species ( Verhoeff 1931), validated a little later through the selection of P. almassyi as type species ( Lohmander 1933), erroneously retypified, by again selecting P. almassyi as type species, by Jeekel (1971). Turanodesmus had been widely in use as a heterogeneous taxon (e.g. Attems 1940) until properly revised by Spelda et al. (1999) and lately shown to be a junior subjective synonym of Jaxartes Verhoeff, 1930 ( Antić et al. 2019).

Diagnosis. Schizoturanius seems to show the closest affinities with the mostly sympatric, Central Asian genus Jaxartes Verhoeff, 1930 , presently with 12 species ranging from eastern Uzbekistan in the west, through southern Kazakhstan and western Tajikistan, to eastern Kyrgyzstan in the east ( Spelda et al. 1999; Antić et al. 2019). Both genera share the peculiar, mostly strongly reduced paraterga and, above all, the gonopod telopodite which is strongly bipartite in Schizoturanius , vs. unipartite, simpler or with a distofemoral process in Jaxartes .

Short description. Length ca. 7–17 mm, body moniliform, with 20 segments (C+17p+1a+T) in adults. Coloration mostly pinkish beige [except for milky white S. tabescens (Stuxberg, 1876) ]. Metatergal polygonal sculpture poorly-developed, more distinct in anterior and posterior body portions, almost obliterate on midbody rings. Paraterga narrow, swollen, weakly rounded, smooth in most species (paraterga of S. tabescens distinctly serrate laterally, with 3–4 rounded, lateral, paratergal teeth).

Gonopods falcate, bipartite only distally or near midway of acropodite, branching into a mesal branch, termed endomere (= solenomere, supporting the seminal groove), and a lateral branch, referred to as exomere (= tibiotarsus). Endomere with an external process in most species ( S. tabescens without an external gonopodal process on endomere). Vulvae devoid of spiral structures at bottom of bursa’s gutter.