Exosehirus, Wagner, 1963

Gapon, Dmitry A., 2021, Revision of the genus Exosehirus (Heteroptera: Cydnidae), with the description of two new species, Acta Entomologica Musei Nationalis Pragae (Acta. Ent. Mus. Natl. Pragae) 61 (1), pp. 133-161 : 159

‘ Exosehirus ’ steini ( Signoret, 1884)

( Fig. 18 )

Canthophorus steini Signoret, 1884: 58 . Sehirus steini : Pඎඍඈඇ (1886: 9); Oඌ*üൺඇංඇ (1906: 25); Vංൽൺඅ (1950: 44);

Lංඇඇൺඏඎඈ*©ං (1984: 2). Sehirus (Tritomegas) steini : Sඍංർ*üൾඅ (1961: 677). Exosehirus steini : WൺǤඇൾ*© (1963: 107); Lංඌ (1999: 223, 2006: 142).

Comments. SංǤඇඈ*©ൾඍ (1884) described Canthophorus steini based on a single male from Sarepta [now in the Volgograd Province of Russia]. He hesitated between assigning this species to Gnathoconus (= Legnotus ) (due to the anterior margin of head with an enclosed clypeus and by the punctured evaporatorium, “plaques ostiolaires perforées”) or to Canthophorus (due to the second segment of the antennae shorter than the third segment).

Later, this species was transferred by Pඎඍඈඇ (1886) to the genus Sehirus , and then conditionally included by WൺǤඇൾ*© (1963) in Exosehirus . It seems that after Signoret described this species, no other researcher examined the holotype or any other specimen: Vංൽൺඅ (1950) and Sඍං- ർ*üൾඅ (1961) included it in their keys to species, but these were explicitly based on the same characters provided in Signoret’s original description; WൺǤඇൾ*© (1963) and Lංඇඇൺඏඎඈ*©ං (1984) wrote that this species was unknown to them. The characters given in the original description of the species and depicted in the figure ( Fig. 18 ) do not correspond to the other species of Exosehirus : i.e., the preocular part of the head with deep notches before eyes and with a deeply concave anterior margin; the bucculae high and truncated posteriorly; the hemelytra with very thin white stripes only on lateral ribs; the mesopleural evaporatorium not continued along the lateral margin of the mesopleuron. Therefore, it cannot be assumed that this is a repeated description of E. validus , which is not mentioned in the work of Signoret. Also, this description does not correspond with any other Sehirinae genera and species. It is not possible to solve this conundrum, since the holotype (it can be concluded that it was a single specimen, since the measurements in the original description are given as separate numbers, and not a range of values, as in other cases), which should be stored in the Zoologisches Museum, Humboldt Universität, Berlin (Lංඌ 1999), is absent there (Jürgen Deckert, pers. comm.). It is also remarkable that for more than 130 years, not a single specimen of this species has been found either in the south of Russia, or in western Kazakhstan, or anywhere else. Due to the impossibility of attributing this nomen dubium to any of the Sehirine genera, I regard E. steini as a species incertae sedis.

Figures

Fig. 18. Drawings of ‘Exosehirus’ steini (Signoret, 1884) from original description.