Digger wasps of the genus Hoplisoides Gribodo (Hymenoptera, Crabronidae, Bembicinae) from the Palaearctic region, with description of two new species

The Palaearctic species of the digger wasps genus Hoplisoides Gribodo, 1884 (Hymenoptera: Crabronidae: Bembicinae) are reviewed, and a key to both sexes is given. Two new species are described and illustrated: Hoplisoides flavescens Mokrousov, sp. nov. (Azerbaijan) and H. leleji Mokrousov, sp. nov. (Turkmenistan). New synonymy is proposed for Hoplisoides craverii (A. Costa), 1867 = Gorytes merceti de Beaumont, 1950, syn. nov. Hoplisoides distinguendus (Yasumatsu, 1939), stat. resurr. is reinstated to full specific level. An updated checklist of the ten species of Hoplisoides so far known from Palaearctic region is provided.

For the first time a detailed diagnosis for the genus leads de Beaumont (1952a). Finally, generic status and features became common accepted after generic revision by Bohart and Menke (1976).
Hoplisoides species, like most other Bembicinae, nest in the ground, generally in bare, sandy soil and dig relatively shallow, normally multicellular nests. The prey of Hoplisoides are various leafhoppers (adults and nymphs of all stages) (Kazenas 2001).
Based on a comprehensive study of specimens in various collections we list here ten Palaearctic species of Hoplisoides, with two species described as new. In addition, we propose new synonymy for Hoplisoides craverii (A. Costa), 1867 = Gorytes merceti de Beaumont, 1950, syn. nov. and reinstate H. distinguendus (Yasumatsu, 1939), stat. resurr. to full specific level. Illustrated keys to the species of Hoplisoides known from the Palaearctic region are presented to facilitate further research on this wasp genus.

Material and methods
This paper is based on the materials, preserved on the collection of the Zoological Institute, Russian Academy of Sciences Photographs taken with a combination of digital camera Canon EOS M200 and Carl Zeiss Stemi 508 (Figs 1A,2A,3A and 4A) and Olympus SZX16 stereomicroscopes (rest figures). Final images representing a composite of several photographs taken at different focal planes and combined using Helicon Focus 7.6.1. All images were post-processed for contrast and brightness using Adobe® Photoshop® v. CC 2017 (×64).
We Key to the species is based on examined collection materials (see below), as well as data from de Beaumont (1950de Beaumont ( , 1952a, R. Turner (1917), andP. Nemkov (1995). The classification and distribution generally follows W. Pulawski (2020).

Genus Hoplisoides Gribodo, 1884
Hoplisoides Gribodo, 1884: 276.  Diagnosis. Genus Hoplisoides, according to Bohart and Menke (1976) with clarifications, characterized by: medium to small wasps; inner eye margins often nearly parallel and widely separated, sometimes converging below, especially in males; median frontal groove often indistinct; labrum inconspicuous; at least male flagellomeres VIII and IX specially modified, flattened or concave beneath; first flagellomere less than three-fourths as long as scape; mandible with an inner subtooth; pronotal collar a little thinner medially, rather closely appressed to scutum; female foretarsal rake well developed, basitarsus with three bladelike setae before apex; female arolia usually equal; posterolateral oblique scutal carina present; mesopleuron with a complete sternaulus; acetabular carina present, distinct and complete; subomaulus lacking or reduced to elevation in the form of an inflection; scutum usually coarsely punctate; forewing usually pictured, media diverging before cu-a, stigma moderate, veinlet of submarginal cell II between recurrents short; jugal lobe larger than tegula, hindwing media diverging at or very near cu-a; midtibia with two apical spurs; metapostnotum usually with longitudinal carinulae, lateral boundaries sometimes indistinct; spiracular groove present but not well impressed; metasomal segment I sometimes narrowed but tergum evenly curved, not strongly humped towards apex, male with normally visible six or seven terga and six sterna, sterna V and VI with basal and concealed hairbrushes (often hidden beneath the edge of the previous sternum), sternum VIII sword shaped and pointed apically; female pygidial plate distinct, often long and ovoid-triangular, sides sometimes bent. Propodeum dorsolaterally smooth, with space not large punctation (Fig. 5E). Male: apical part of clypeus concave, concavity narrowed in middle (Fig. 5D); mid tarsomeres 2 and 3 modified, assymetrical, tarsomere 2 with long process posterioapically (Fig. 6E)  Punctation of metanotum and propodeal dorsolateral surface with coarse punctures, without smooth interspaces. Omaulus-sternaulus at junction with acetabular carina not or slightly curved. Female: tentorial pit situated about middle at frontoclypeal suture between eye and antennal socket (Fig. 7E); flagellomeres longer, F1 L/W = 2.42, F 9 distinctly longer than wide (Fig. 7D); mid tarsomeres thinner (Fig. 7C). Male: tentorial pit situated distinctly closer to eye at frontoclypeal suture between eye and antennal socket (Fig. 7F); flagellomeres longer, F1 L/W ca. 1.5, F 10 distinctly longer than wide, antennal tyloids more developed, on basal flagellomeres distinct (Fig. 7H)    Remark. De Beaumont (1952a: 223) changed the state of Gorytes merceti de Beaumont to rank of subspecies of Hoplisoides craverii (A. Costa). As the only differences between these forms, he cited coloring features of the clypeus and legs. The study of the material from Spain, Russia (Crimea, Dagestan), Azerbaijan, Turkey, Turkmenistan, Uzbekistan and Kazakhstan showed a high variability of these characteristics. We consider ssp. merceti de Beaumont is only a color variation of a rather variable species with a range of color geographic forms. (Yasumatsu, 1939), stat. resurr. Remark. The reason to reduce the status of distinguendus to rank of subspecies of gazagnairei was, most likely, a similar form of males clypeus (apical part of the clypeus concave). The modified clypeus is not unique for these two taxa: clypeus with separated apical part present in the North American Hoplisoides hamatus (Handlirsch, 1888), H. nebulosus (Packard, 1867), H. placidus (F. Smith, 1856) and H. punctifrons (Cameron, 1890) (Buck, 2007). Besides, H. gazagnairei and H. distinguendus have many significant differences (besides coloration), given in the Table 1.
Description. Female. Body length 9.6-11.4 mm (holotype 9.6 mm); fore wing length of holotype 7.3 mm. Head (Fig. 1C, D). Head ratio H:W = 0.85; POL:OOL = 1.45; eyes slightly convergent downwards. Frons above antennal sockets without longitudinal elevation (carina). Occipital carina well developed; it does not reach hypostomal carina at distance slightly larger than diameter of anterior ocellus. Antennae elongate, all flagellomeres distinctly longer than wide. Mandibles with internal blunt tooth in apical third. Punctation above antennal sockets and temples sparse; along inner edges of eyes and at vertex dense, interspaces less than punctures diameter; clypeus in central part with several large punctures. Mesosoma. Acetabular carina acute, far from reaching omaulus, laterally connects to subomaulus reduced to elevation in form of inflection; omaulus-sternaulus acute, uniform, not curved. Metapostnotum well separated, with shallow medial furrow with transverse ribs and lateral folds diverging to posteriorly. Propodeal slope with strong median keel and distinct transverse carinae. Punctation on pronotal collar sparse; on mesonotum and scutellum irregular, deep, with micropuntured interspaces; mesopleuron with dense punctation, more sparse ventrally and posterolaterally; dorsolateral parts of propodeum with irregular dense punctation. Wings (Fig. 1E). Venation typical for genus; hindwing media diverging at cu-a. Legs. Foretarsal rake well developed, basitarsus with three rake setae before apex; setae slightly spatulate. Metasoma. T1 not elongate, approximately as long as width. Pygidial plate broad, sharply edged, with elongated punctures forming irregular longitudinal wrinkles. Punctation of T1 irregular, interspaces much larger than punctures diameter; T2-T4 with smaller punctures, interspaces about punctures diameter; T5 with obscure punctato-wrinkled sculpture; S2-S5 scattered punctured, punctures on S2 large. Coloration (Fig. 1A). Predominantly yellow with black pattern. Black or brown are: apical third of mandibles, upper part of frons and vertex between eyes, back part of head, stipes, prementum; pronotum (except collar and lobes), median and posterior parts of mesonotum, anteroventral and posterolateral parts of mesopleuron, metapleuron and propodeum (except large lateral spots); arolia; decreasing from metasomal base to top, basal bands on T1-T4 (at holotype on T5 also); S1 basally, S2 anterolateral spots and narrow anterior band (interrupted at holotype), S3 anterior band and T6 entire. Upper of scape, pedicel and antenna, basal dorsal spots or stripes on fore-and midfemora, longitudinal stripe on hind femur and tibia, apex of hind tarsomeres, are brownish. Forewing with darkened area on radial cell, apex of submarginal cell I, submarginal cell II and anterior part of submarginal cell III; isolated small darkening at apex of median cell. Setation ill developed; head along inner edges of eyes and lateral parts of clypeus with dense silvery pubescence. Stout setae on clypeus, labrum and mandibles.
Etymology. Species name derivate from adjective Latin word "flavescent" -becoming yellow, and characterizes a well-developed yellow coloration.

Hoplisoides gazagnairei (Handlirsch, 1893)
Gorytes  de Beaumont 1952a: 227) was described based on slight differences of the colour of metasoma. This character varies with the climatic conditions the wasps live in and usually is unsuitable for a taxonomic differentiation. This taxon is probably synonym of Hoplisoides gazagnairei (Handlirsch), but for the final conclusion it is necessary to study the types or specimens from the type locality (Morocco).

Hoplisoides leleji
Male differs also: tentorial pit situated about middle at frontoclypeal suture between eye and antennal socket (distinctly closer to eye on H. latifrons); flagellomeres shorter, F1 L/W = 1.23, F10 slightly longer than wide (F1 L/W ca. 1.5, F 10 distinctly longer than wide on H. latifrons), antennal tyloids weaker developed, on basal flagellomeres very short (distinct on H. latifrons). Morphological differences from all Palaearctic species given in key.
Description. Female. Body length 9.6-10.6 mm (holotype 9.6 mm); fore wing length of holotype 7.2 mm. Head (Figs 3C-D). Head ratio H:W = 0.77; POL:OOL = 1.09; eyes slightly convergent downwards. Frons above antennal sockets without longitudinal elevation (carina). Occipital carina well developed; it does not reach hypostomal carina at distance larger than diameter of anterior ocellus. Tentorial pit situated distinctly closer to antennal socket at frontoclypeal suture between eye and antennal socket (Fig. 3F); flagellomeres shorter, F1 L/W = 1.81, F9 cubelike. Punctures deep, but scattered on frons (from below with several punctures only), clypeus and back side of head, more dense on vertex. Mesosoma (Fig. 3H). Acetabular carina reaching omaulus, omaulus-sternaulus at junction with acetabular carina curved. No subomaulus. Metapostnotum well separated, with weak medial furrow and lateral folds diverging to posteriorly. Propodeal slope with strong median keel and irregular adjoining sculpture or transverse rugae. Punctation on pronotal collar and scutellum small and sparse; on mesonotum irregular, deep, but sparse; mesopleuron and sides of propodeum punctation sparse, with large smooth interspaces; dorsolateral parts of propodeum irregular punctured, with noticeable smooth interspaces. Wings (Fig.  3E). Venation typical for genus; hindwing media diverging at cu-a. Legs. Foretarsal rake well developed, basitarsus with three rake setae before apex. Metasoma. T1 not elongate, approximately as long as width. Pygidial plate broad, sharply edged, with elongated little smoothed punctures. Punctation of T1 irregular, dense at base and sparse posteriorly; T2 with large, T3-T5 with smaller irregular punctures; S2 with large S3-S6 with smaller scattered punctures. Coloration (Fig. 3A). Black and brown with rich yellow pattern. Yellow are: clypeus (except apical border), spot laterally of antennal socket and large spot along inner edge of eye, narrow strip at posterior margin of eye; scape and pedicel from below; pronotal collar and lobes, small spot on mesonotum near axilla, scutellum, large spot on mesopleuron, lateral large propodeal spot; metanotum on holotype marked yellow (black on paratype); wide apical bands on T1-T5 (T5 predominantly yellow) and apicolateral spot on S2. Apical border of clypeus, labrum, middle part of mandibula and basal flagellomeres from bellow brownish. Fore-and mid legs yellow with black coxae, trochanters, base of femora and apicoposterior spot on tibiae. Hind coxa and trochanter black; hindfemur and hindtibia posteriorly, hind tarsus completely brownish. Forewing with darkened area on radial cell, submarginal cell II and anterior part of submarginal cell III. Setation ill developed; head along inner edges of eyes and lateral parts of clypeus without silvery pubescence. Stout setae on clypeus, labrum and mandibles.
Etymology.The species is named after famous Russian entomologist Arkady S. Lelej (FSCV), who collected the type series of the new species.

Hoplisoides punctuosus (Eversmann, 1849)
Remark. Gorytes curtulus A. Costa, 1893: 100 (=Hoplisoides punctuosus curtulus (A. Costa) according to de Beaumont 1952a: 222) was described based on slight differences of the colour of femurs and antenna and the breadth of apical metasomal hair bands. These characters vary with the climatic conditions the wasps live in and usually are unsuitable for a taxonomic differentiation. This taxon is probably synonym of Hoplisoides punctuosus (Eversmann), but for the final conclusion it is necessary to study the types or specimens from the type locality (Tunisia).