Disparrhopalites Stach, 1956

Wynne, J. Judson, 2017, Disparrhopalites naasaveqw n. sp. from caves at Wupatki National Monument, Arizona, synonymy of Dietersminthurus Palacios-Vargas, Cuéllar & Vázquez, 1998 with Disparrhopalites Stach, 1956 and composition of Songhaicinae (Collembola: Sminthuridae), Zootaxa 4319 (1), pp. 77-90 : 81

Disparrhopalites Stach, 1956

Disparrhopalites Stach, 1956:63 .

Dietersminthurus Palacios-Vargas, Cuéllar & Vázquez, 1998:13, new synonym.

Type species: Disparrhopalites patrizii ( Cassagnau & Delamare Deboutteville, 1953) Other species:

D. enkerlinius ( Palacios-Vargas, Cuellar & Vazquez, 1998) n. comb. D. naasaveqw n. sp.

D. tergestinus Fanciulli, Colla & Dallai, 2005

Pararrhopalites patrizii Cassagnau & Delamare Deboutteville, 1953 was transferred to the new genus Disparrhopalites by Stach (1956). This widespread European species ( Dallai 1971, Fanciulli et al. 2005) has been collected and studied thoroughly since then ( Christian 1998; Dallai 1970, 1971; Delamare Deboutteville & Bassot 1957; Fanciulli et al. 2005; Gama 1988, 2005; Marx & Weber 2013, 2015). However, Disparrhopalites was not compared to more recently described but clearly similar genera (Dietersminthurus, Gisinurus, Songhaica , Soqotrasminthurus , Varelasminthurus , see Tables 1 & 2 for authorities and dates), perhaps because the two known Disparrhopalites spp. lack a prominent cavity-like formation on the unguis. The type species, D. patrizii , possibly a weak troglophile, has a shallow linear cavity while the highly modified troglobiont D. tergestinus apparently lacks the cavity completely. Disparrhopalites naasaveqw n. sp., a presumed obligate troglophile, is very similar to D. patrizii but has a distinct ungual cavity. The ungual cavity may be a synapomorphy for this small clade of species that secondarily disappears with increasing troglomorphy. This scenario could account for the reduction of the cavity in D. patrizii and its complete loss in D. tergestinus , as well as its retention in D. enkerlinius and D. naasaveqw n. sp.

The monospecific genus Dietersminthurus was differentiated from similar genera by the presence of 5+5 eyes and eight setae on the anterior face of the dens ( Palacios-Vargas et al. 1998). The reduction in eye number is recognised in a few other sminthurid genera, and the number of dental setae can be species-specific in several genera, e.g., Sminthurus s. str. Latreille, 1802 (see Bretfeld 1999) and Sminthurinus Börner, 1901 ( Christiansen & Bellinger 1998). Ungual structure in D. enkerlinius appears to be identical to that of D. patrizii except that the ungual cavity is well-developed in D. enkerlinius and weakly developed in D. patrizii , and D. enkerlinius possesses eight anterior dental setae while D. patrizii has nine. Disparrhopalites naasaveqw n. sp. bridges these species by having a patrizii -like unguis with a well-developed enkerlinius -like cavity and nine anterior dental setae as in other Disparrhopalites spp. Therefore, Dietersminthurus is considered a junior subjective synonym of Disparrhopalites , and its sole species , Dietersminthurus enkerlinius , becomes Disparrhopalites enkerlinius ( Palacios-Vargas, Cuéllar & Vázquez, 1998) n. comb.

Varelasminthurus was separated from similar genera by the absence of the posterior pretarsal seta ( Da Silva et al. 2015). The number of pretarsal setae of Disparrhopalites naasaveqw n. sp. varies (1 or 2) from leg to leg, and therefore this character may not have significant validity at the generic level in Songhaicinae . However, the tunica of the single species, V. potiguarus Da Silva, Palacios-Vargas & Bellini, 2015 , is heavy and fused to an external crest-like, serrated pseudonychium ( Da Silva et al. 2015). Therefore, despite its similarities with Disparrhopalites spp. it is maintained here as a valid genus.