Tachysphex mongolicus Kohl, 1898

Mokrousov, Mikhail V. & Proshchalykin, Maxim Yu., 2021, New and little-known digger wasps (Hymenoptera: Ampulicidae, Sphecidae Crabronidae) from Russia, Zootaxa 4952 (2), pp. 314-330 : 324-326

Tachysphex mongolicus Kohl, 1898 , stat. resurr.

( Figs 29–35 )

Tachysphex mongolicus Kohl, 1898: 99 , ♀. Holotype: ♀, northern Mongolia [NHMW]. Junior subjective synonym of Tachysphex nasalis Morawitz, 1893 according to Puławski 1971: 84. Stat. resurr.

Tachysphex abditus Kohl, 1898: 101 , ♀. Holotype: ♀, northern Mongolia [NHMW]. Junior subjective synonym of Tachysphex nasalis Morawitz, 1893 according to Puławski 1971: 84. Syn. nov.

Tachysphex nasalis: Puławski 1971: 84 (part).

Material examined. Russia. Tyva Rep., 2 ♀, 25 km SE Erzin vill., Tes-Khem Riv. [50.076°N 95.37°Е], 14.VII.2014, AL, MP, VL ; 2 ♂, 2 km SW Samagaltay vill. [50.518833°N 94.88665°E], 6–10.VII.2013, MP, VL ; 1 ♀, ibid., 17.VII.2014 AL, MP, VL ; 1 ♂, 31 km NEE Erzin vill., Erzin Riv. [50°21’N 95°33’E], 18.VII.2014, AL, MP, VL [ MMC] .

Distribution. * Russia (Tyva Rep.); Mongolia.

Remarks. The females of Tachysphex mongolicus Kohl, 1898 and T. abditus Kohl, 1898 were synonymized with the male of T. nasalis Morawitz, 1893 by Puławski (1971: 84) as opposite sex of the same species. The discovery of hitherto unknown male and study of additional females of T. mongolicus / T. abditus collected near the type locality (Tyva Republic, Russia vs Northern Mongolia) allowed to reinstate T. mongolicus as a valid species and propose new synonymy.

Diagnosis. Tachysphex mongolicus belongs to T. pompiliformis species group and species complex containig T. bouceki Straka, 2005 , T. excelsus R. Turner, 1917 (= T. mysticus Pulawski, 1971 ), T. morawitzi Pulawski, 1971 , T. nasalis F. Morawitz, 1893 , T. punctipes Pulawski, 1967 , and T. splendidulus F. Morawitz, 1893 , which are defined by the following combination of characters (according to Straka, 2005 with modification): ♂, ♀: sculpture of mesopleuron dull, shagreened or rugose; ♂: forebasitarsus with rake; inner side of volsella with ledge ( Fig. 31 ) (in a few species missing); ♀: weak punctuation on medial lobe of clypeus developed only at laterobasal corners; medial lobe of clypeus with more or less distinct median emargination; outer surface of fore tibia and posteroexternal surface of mid tibia impunctate and shiny.

Both sexes: base of metasoma red (on T. punctipes metasoma completely black). Female (unknown in T. nasalis ): medial lobe of clypeus with lateral incisions (absent in T. splendidulus ); setae of vertex about 0.5–1.0× MOD (1.0× in T. bouceki , 1.2–1.5× in T. excelsus , 1.5× in T. morawitzi , 1.0× in T. punctipes , 0.3× in T. splendidulus ); medial lobe of clypeus strongly convex, without preapical flattening or depression (apical part concave in T. morawitzi and flattened in most specimens of T. excelsus ) and large punctures (lacking in T. splendidulus ); fore and midfemora ventrally with distinct large punctures on shiny surface (micropunctate in T. excelsus and inpunctate in T. splendidulus ); mesoscutum (except anterior part) and scutellum with very sparse few punctures ( Fig. 35 ) (same in T. splendidulus ). Male (unknown in T. splendidulus ): mandible with one inner tooth (same as in T. punctipes ), in other species with two inner teeth ( T. bouceki , T. excelsus ) or tooth absent ( T. morawitzi , T. nasalis ); medial lobe of clypeus slightly arcuate (pointed in T. nasalis ); volsellar setae scattered ( Fig. 31 ) (more numerous in other species); dorsal volsellar process high ( Fig. 31 ) (lower in other species).

Description of hitherto unknown male. Total body length 8.5–9.4 mm. Coloration: mandible mesally, tegula, edge of pronotal tubercles, forefemoral notch, all or four apical tarsomeres, three basal metasomal segments ferruginous; mandibles brownish apically; other parts black.

Head ( Figs 32, 34 ). Head ratio H:W = 0.76; genae relatively narrow, evenly converging behind compound eyes (dorsal view); vertex wide, WV:LV = 1.93. Labrum flat, almost semicircular. Medial lobe of clypeus without median emagination, narrow and short, slightly rounded or almost straight, not projecting angularly on sides, clearly separated from bevel by strong transverse bend, its anterolateral margins carinated, passing into bevel’s lateral carina; basomedian area and bevel not separated by transition, clypeus (except medial lobe) uniformly distinctly convex, surface without micropunctation, almost reaches clypeal base at midle; bevel bright shiny, with few large punctures ( Fig. 34 ). Mandible with one inner tooth. Frontal median sulcus deep. Frons and vertex distinctly punctate, punctures on frons irregular, from one to many diameters apart, interspaces dull, with microsculpture. Vertex with dense and smaller punctures, less than one diameter apart, interspaces shiny; genae densely punctate with very fine and indistinct punctures; postocellar impression deep, rounded, weakly limited. Pubescence weak; setae on vertex about 0.5–1.0× MOD.

Mesosoma. Scutal punctures irregular, anteriorly and laterally less than one diameter apart, central part with punctures half to three or more diameters apart with large shiny interspaces; scutellum sparsely punctate, punctures well developed and 2–3 or more diameters apart. Mesopleuron with shagreened and rugose sculpture, without punctures, dull; ventral part with clear, rather scattered punctures (one–three diameters apart). Episternal sulcus far not reach mesopleural anterior edge. Pubescence weakly developed, mesonotal anterolateral setae length about MOD, distinctly longer on sides of propodeum. Wings with slight yellowish tinge. Legs: forefemoral notch not deep, not larger than distance between it and forefemoral base, notch impunctate, microsetose, slightly shiny ( Fig. 33 ); fore and midfemora ventrally and all trochanters shiny, distinctly punctate, mid trochanter with few large punctures ventrally; tarsal rake developed. Propodeal dorsum rugose; lateral and posterior parts densely and coarsely striate.

Metasoma. TI–TIII with indistinct silvery apical bands. Tergal and sternal punctures ill-defined (except apical terga), interspaces slightly shiny. Penial valve as in Fig. 30 . Volsella ( Fig. 31 ) with high dorsal process, inner side with ledge.

Figures

FIGURES 29–34. Tachysphex mongolicus Kohl, male (from Tyva Rep.): 29—habitus, dorsolateral view; 30–31—genitalia, lateral view, apical part of penial valve (30), volsella (31); 32—head, frontal view; 33—forefemur, ventral view; 34—clypeus. Scale bar: 2.0 mm.

FIGURES 35–37. Scutum, scutellum and metanotum of Tachysphex females: 35—T. mongolicus (from Tyva Rep.); 36—T. stysi Straka (from Uzbekistan); 37—T. austiacus Kohl (from Kazakhstan).