Razianus xinjianganus Lourenço, Sun & Zhu, 2010

Razianus xinjianganus Lourenço, Sun & Zhu, 2010 View in CoL

( Figure 3 View Figure 3 ) http://zoobank.org/urn:lsid:zoobank.org:act:467E2322-

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TYPE MATERIAL. China, Xinjiang Uyghur Autonomous Region, Kashgar (or Kaxgar) Prefecture, near Tajikistan , April 1971, holotype ♀, leg. C. Naumann ; MHBU (lost, a neotype should be designated as per Yanega et al. (2018) once this species is rediscovered) .

AFFINITIES. The following comparison with two Xinjiang buthids is based on the original description and the assumption that it is a valid species since the type is lost. This part is included to facilitate future investigators in rediscovering this species .

Although R. xinjianganus can be distinguished by its small adult size (ca. 20 mm in ♀), confusion may still arise for the inexperienced when attempting to differentiate it from the juveniles of Mesobuthus thersites (C. L. Koch, 1839) (adult size: 32 mm in ♂ to 60 mm in ♀; Kovařík et al., 2022: 139) and Olivierus przewalskii (adult size: 44–53 mm in ♂ and 49–63 mm in ♀) based on the overall habitus. Razianus xinjianganus is similar to M. thersites in its robust chela (vs. slender in, particularly the juvenile, O. przewalskii ), and to O. przewalskii in its slender metasoma and finely granulated metasomal carinae (vs. robust and strongly dentate in, particularly the adult, M. thersites ). A single meristic, PTC, serves as the most convenient diagnostic feature for differentiating females: 17–23 in M. thersites , 16–20 in O. przewalskii , and 12 in R. xinjianganus . Female R. xinjianganus is well separated from the other two buthids. Another, albeit less convenient, meristic feature is the number of pedipalp movable finger denticle subrows, which ranges from 11–12 in M. thersites and 9–11 in O. przewalskii , whereas R. xinjianganus has only 7–8 rows. DISTRIBUTION ( Fig. 3 View Figure 3 ). China (Xinjiang: Kashgar Prefecture). The exact location of this species in Xinjiang cannot be determined. Based on the known distribution pattern of its congeners which indicates the incapability of trans-mountain dispersal of this genus ( Tahir et al., 2014: fig. 1), the Pamir Mountain range may also act as an insurmountable physical barrier that confines the distribution of R. xinjianganus to the east, in the west end of the Tarim Basin of Xinjiang.