Leptochilus (Lionotulus) incertus ( Kostylev, 1940 )

Fateryga, Alexander V., 2024, On some new and little-known Palaearctic species of the genus Leptochilus de Saussure, 1853 (Hymenoptera: Vespidae: Eumeninae), Zootaxa 5432 (1), pp. 38-53 : 42-45

Leptochilus (Lionotulus) incertus ( Kostylev, 1940)

( Fig. 3A–H )

Odynerus incertus Kostylev 1940: 33 , ♀ (type locality: “ Baïn-Houdouk, Nord Alachan , Mongolie” [ China: Inner Mongolia]; holotype, ♀, ZISP.

Diagnosis. The species belongs to a group of the subgenus Lionotulus with pronotal carina lamellate, metanotum sharply edged posteriorly, hind trochanter rounded posteriorly, and apical lamella of T2 not largely sclerotized, with rather rounded basal punctures; it can be recognized, among similar species occurring in the northeastern part of Central Asia, by the occipital carina forming a distinct obtuse angle at the lower part of the gena, the anterior pronotal carina not concave medially, the median carina developed at lower half of the propodeal concavity, and the wings fully transparent.

Description. Female. Body length (from head to apical margin of T2) 5 mm; forewing length 4.5 mm. Head about 1.15× as wide as long in frontal view. Mandible with four teeth. Labial palpus not modified. Clypeus about 1.4× as wide as long, its apical emargination very shallow, taking less than 1/4 of clypeal width, apical teeth acute and strongly carinate. Distance between lateral ocellus and occipital margin exceeding distance between lateral ocellus and eye. Occipital carina forming distinct blunt angle at lower part of gena. Anterior pronotal carina strongly lamellate; lamella as high as half diameter of ocellus, interrupted medially. Tegula with outer margin rounded posteriorly, about as long as scutellum. Scutellum rather evenly convex. Metanotum not raised above scutellum, sharply edged posteriorly. Hind trochanter rounded posteriorly. Propodeum with indistinct dorsal surface only; propodeal concavity with rounded lateral margins; median carina developed at lower half of propodeal concavity. Projection of submarginal carina of propodeum longer than wide, bluntly rounded apically; valvula rounded. Apical lamella of T2 semitransparent, with basal row of rounded to slightly elongated punctures, interstices sclerotized up to at most 1/3 of lamella. T3 and T4 with similar but indistinct apical lamellae. S 2 in lateral view roundly elevated at base, in ventral view with distinct longitudinal furrow.

Clypeus densely punctate with shallow punctures, more coarsely on apical part; interstices mostly not reaching puncture diameter, with microsculpture. Punctures on frons and vertex more distinct than on clypeus, interstices reaching one puncture diameter, shining, with little microsculpture; gena with somewhat finer punctures than on frons and vertex and similar microsculpture. Dorsal surface of pronotum punctate similarly to vertex; punctures become coarser on scutum and scutellum, interstices reaching one puncture diameter, shining, with few microsculpture. Tegula shining, with microsculpture only. Dorsal mesepisternum, ventral mesepisternum, and mesepimeron with punctures somewhat smaller than those on pronotum, interstices reaching several puncture diameters, shining, with microsculpture. Epicnemium shagreened, without distinct punctures. Metanotum with coarse punctures on upper part of posterior side and weak microsculpture only on lower part. Metapleuron longitudinally rugose. Dorsolateral surface of propodeum dull, with hardly visible shallow dense punctures and dense microsculpture. Lateral surface of propodeum longitudinally rugose; sculpture of propodeal concavity similar to that on lateral surface but interstices shining. T1 and T2 sparsely punctate with small shallow punctures, interstices reaching several puncture diameters, with dense microsculpture. S1 coarsely rugose longitudinally. S2 punctate similarly to T2. Following terga and sterna without distinct punctures, with dull microsculpture only.

Posterior side of mandible with straight pale setae somewhat longer than F1. Lower half of frons, basal half of clypeus, and dorsolateral surface of propodeum with dense silver appressed setae. Upper half of frons and apical half of clypeus with straight pale setae as long as diameter of F1 at distal end. Scapus and gena with very short setae only. Labial palpus with several setae as long as diameter of F1 at distal end. Vertex and dorsal surface of mesosoma with straight setae about as long as diameter of F1 at base. Ventral surface of mesosoma and whole metasoma with short appressed setae only.

Basal color black. Following parts pale yellow: basal half of clypeus, anterior side of scapus, anterior band on pronotum (interrupted medially), spot on dorsal mesepisternum, tegula (except central brownish spot), parategula, band on metanotum, lateral spots on propodeum, apical band on T1 enlarged laterally, lateral spots and apical band on T2, narrow apical band on S2, central spots on distal ends of T3 and T4, distal ends of femora, entire tibiae. Ventral side of antenna ferruginous. Tarsi brownish-yellow. Wings transparent; veins light brown.

Male. Body length (from head to apical margin of T2) 4.5 mm; forewing length 4 mm. Structure resembles that in female except the following: head about 1.1× as wide as long in frontal view; clypeus about 1.1× as wide as long, its apical emargination about 0.5× as deep as wide, taking about 1/5 of clypeal width; F11 rather triangular, pointed apically, reaching apical margin of F8; F9 with shallow depression housing apex of F11. S7 with most area flattened. Digitus long, narrow, and rather pointed apically.

Sculpture similar to that in female but clypeus very dull, without visible punctures, with microsculpture only.

Setae mostly as in female but clypeus entirely covered with dense white appressed setae as long as diameter of F1 at base; labial palpus without long setae.

Coloration mostly as in female but clypeus entirely whitish-yellow; spots on dorsal mesepisternum, propodeum, and T2 absent; scutellum, S2, T3, and T4 also black. Depression of F9 and entire F10 and F11 ferruginous.

Material examined. HOLOTYPE: ♀, labeled “Баинхудук / с. Алашань / КОЗЛОв 20V909 [Bainkhuduk, N Alashan, leg. P. Kozlov, 20.V.1909] // incertus Typ. ♀ / G Kostylev det. 36 // Holotypus [red label]” [ ZISP] . ADDITIONAL MATERIAL: MONGOLIA: Ömnögovi Province, Undyn-Gol Ravine , 25 km S Mt. Khan-Bogdo, 7.VIII.1971, 1 ♂, leg. I. Kerzhner [ ZISP] .

Distribution. Mongolia (new record); China: Inner Mongolia.

Remarks. The genitalia of this species are not illustrated because the examined male specimen lacks a major part of the aedeagus, for unknown reason.

Leptochilus incertus is apparently closely related to a recently described L. angulus Bai, Chen & Li, 2024 , from Inner Mongolia as well. The latter species differs from L. incertus by the anterior pronotal carina concave medially, the black scapus in the female, and fuscous wings ( Bai et al. 2024). Leptochilus incertus is also very similar to L. locuples sensu Bai et al. (2024) from Gansu. The latter misidentified specimen has, however, somewhat longer clypeus, not developed median carina of the propodeum, and a yellow band on the metanotum ( Bai et al. 2024). More material is required to ascertain whether L. locuples sensu Bai et al. (2024) is conspecific with L. incertus or represents a separate species. The true L. locuples Giordani Soika, 1970 is distributed in Turkmenistan and Uzbekistan ( Fateryga et al. 2023) and probably does not occur in China; it differs from the misidentified specimen by many characters, including the occipital carina not forming an angle at the lower part of the gena and a very different color pattern.

The third species with the occipital carina forming a distinct obtuse angle at the lower part of the gena in the paper by Bai et al. (2024) is also misidentified. It is reported as L. callidus ( Kostylev, 1940) but the true L. callidus differs from it by many characters, including the occipital carina not forming an angle at the lower part of the gena, a lamellate pronotal carina, and a different color pattern; it is distributed in Iran, Uzbekistan, and Kazakhstan ( Fateryga et al. 2023). Leptochilus callidus sensu Bai et al. (2024) differs from L. incertus , first of all, by the pronotal carina not lamellate. Both true L. locuples and true L. callidus has hind trochanter sharply edged posteriorly while it is rounded posteriorly in L. incertus . The structure of the hind trochanter of L. angulus , L. locuples sensu Bai et al. (2024) , and L. callidus sensu Bai et al. (2024) is not reported.

Figures

FIGURE 3. Leptochilus incertus (Kostylev, 1940).A–C, F, ♀, holotype; D, E, G, H, ♂, Mongolia.A, D, habitus in lateral view; B, E, head in frontal view; C, labels; F, G, mesosoma in dorsal view; H, apex of flagellum. Scale bars 1 mm.