A new species of the genus Deinodryinus Perkins (Hymenoptera, Dryinidae) from the USA

Abstract A new species of Deinodryinus Perkins, 1907, is described from the USA, Texas: D.bimaculatussp. n. Morphologically the new species is similar to D.masneri (Olmi, 1984), but it is distinguished by the head lacking a frontal line and the forewing crossed by two dark transverse bands; in D.masneri the head shows a conspicuous frontal line and the forewing is hyaline and without dark transverse bands.

One of the most common genera of this family is Deinodryinus Perkins, 1907, belonging to the subfamily Anteoninae. Deinodryinus species are parasitoids of leafhoppers belonging to the Cicadellidae (Guglielmino et al. 2013;Olmi and Virla 2014;Olmi and Xu 2015). As in almost all dryinids, females of Deinodryinus have a chelate pro tarsus. Chelae are used to capture and restrain the host during oviposition and host feeding (Olmi 1984(Olmi , 1994.
According to Olmi (1984Olmi ( , 1987, in the Nearctic region, the genus Deinodryinus includes four species. In 2017 the authors examined a further new species collected in Texas. It is described below.

Material and methods
The description follows the terminology used by Olmi (1984), Guglielmino et al. (2017bGuglielmino et al. ( , 2018 and Olmi and Virla (2014). The measurements reported are relative, except for the total length (head to abdominal tip, without the antennae), which is expressed in millimeters. In the descriptions, POL is the distance between the inner edges of the lateral ocelli; OL is the distance between the inner edges of a lateral ocellus and the median ocellus; OOL is the distance from the outer edge of a lateral ocellus to the compound eye; OPL is the distance from the posterior edge of a lateral ocellus to the occipital carina; TL is the distance from the posterior edge of an eye to the occipital carina.
The types of all Nearctic species of Deinodryinus were examined. The material studied in this paper is deposited in the collection of the Department of Entomology, Texas A&M University, College Station, Texas, USA (TAMU).
The description of the new species is based on the study of only a single specimen. The authors are aware that descriptions of new taxa should normally be based on more individuals. However, Dryinidae are so rare that it is uncommon to collect more than one specimen of each species. In addition, on the basis of the experience and knowledge of the authors, the new species is sufficiently delimited by unique characters to justify its description.
Remarks. On the basis of the morphological characters indicated in the above diagnosis, D. bimaculatus is similar to D. masneri (Olmi, 1984), but it differs because the head has no frontal line (frontal line present in D. masneri) and the forewing has two dark transverse bands (no dark bands in D. masneri). Following the description of the new species, the key to the females of Nearctic Deinodryinus published by Olmi (1984) can be revised as follows: 1 Metapectal-propodeal complex strongly reticulate rugose, mainly on metapostnotum (Figs 1D, 2D) Olmi (1984Olmi ( , 1987 listed in the Nearctic region the following four species of Deinodryinus: D. atriventris (Cresson, 1872), known from Canada, Mexico and USA; D. masneri (Olmi, 1984), D. paradoxus Perkins, 1907, andD. quercicolus Perkins, 1907, known from Mexico and USA. Following the above description, D. bimaculatus sp. n., from Texas, is added to the previous lists.

Conclusion
The genus Deinodryinus comprises now 163 species (including the new species hereby described), recorded in all the zoogeographic regions, except Antarctica. In the Neotropical region, 112 species are known (Olmi and Virla 2014). In the other regions the number of known species is fewer: nine species in the Oriental region (Xu et al. 2013), seven species in the Palaearctic region (unpublished data), 28 species in the Afrotropical region (unpublished data), two species in the Australian region (Olmi 1991); and five species in the Nearctic region (according to the present paper).