Idiotypa Förster, 1856

Chemyreva, Vasilisa G., Notton, David G. & Zaldívar-Riverón, Alejandro, 2021, Revision of Palaearctic Idiotypa (Hymenoptera, Diapriidae, Diapriinae, Spilomicrini), Zootaxa 4966 (2), pp. 127-144 : 129-130

Idiotypa Förster, 1856

Ruthe, 1859: 123; Kieffer, 1905: 36, 39; 1916: 11, 14, 49; Kozlov 1971: 20; 1978: 594; Masner & García, 2002: 16, 17, 23–26; Nixon, 1980: 10, 11, 14.

Idiotypa Förster, 1856: 122 , 125 (type species: Psilus maritimus Haliday, 1833: 275 , designated by Ashmead, 1893). Diapria (Mionopria) Haliday, 1857: 166 , 170 (type species: Psilus maritimus Haliday, 1833 , by monotypy) Neopria Dodd, 1915: 398 , 429 (type species: Neopria trifoveata Dodd, 1915 , by original designation). Eunuchopria Szabó, 1961: 491 (type species: Eunuchopria nitens Szabó, 1961 , by monotypy and original designation). Syn. n.

Diagnosis. Length of body small to medium-sized (1.0‒3.5 mm), robust. Body often pale, reddish orange to yellow, less frequently brown to dark brown, mostly smooth, with abundant setae. Setose cushions weakly developed on postgena and pronotum; foamy structures not developed. Ocelli without semicircular groove posteriorly. Antennal shelf weakly developed; toruli separated by deep gap and not connected by carina. Clypeus not separated from supraclypeal area by epistomal sulcus. Labrum not exposed.Antenna of male 13-of female 12-segmented. Propleuron without reticulation. Posterior pronotal sulcus absent. Scutellum with three (rarely more than three) pits anteriorly. Lobe of anterior mesopleural area absent and epicnemial pit open ventrally ( Fig.18 ). Mesepimeral and transpleural sulci present; mesopleural carina and matt spot on mesopleuron above mesocoxa absent. All trochantelli present. Tegula, if present, covering lateral subapical lobe of humeral complex of fore wing base only partly. Fore wing, if present, with venation distinctly exceeding basal half of wing length (stigmal vein almost perpendicular to marginal vein, postmarginal vein present). Hind wing, if present, without closed basal cell. Median and lateral grooves present on T2 and S2; S2 without setose lines. S2 without basal cushion of setae; last sternite (S6) of female equal to or shorter than S3–S5 sternites combined.

Remarks. The examined external morphological features and DNA sequence data support the allospecificity of Idiotypa maritima (Haliday) and I. mariae Gregor. Both species are widely distributed in Palaearctic from West Europe to Japan. Examination of the type material, the lectotype of I. nigriceps Kieffer, 1909 (the same specimen also the lectotype of I. nigriceps Kieffer, 1911 ), the lectotype of I. rufiventris (Thomson) , and the lectotype of I. maritima (Haliday) , clearly shows that these names are synonyms.

The species Eunuchopria nitens Szabó, 1961 , originally described in the monotypic genus Eunuchopria ( Szabó, 1961) , appears at first sight very different from Idiotypa , most noticeably by its aptery in both sexes, lack of ocelli, notauli, tegulae, axillae and axillar depressions; scutellum only visible as narrow transverse sclerite with only scutoscutellar sulcus between it and mesoscutum. However this is an expression of a common suite of reduction characters associated with extreme wing reduction and fossorial habits, which appears to have arisen commonly in several unrelated genera of diapriines. Similar extreme examples can be found in some undescribed species of Idiotypa from Chile and Argentina ( Masner & Garcia, 2002), Spilomicrus myrmecophilus Nixon (females) and Platymischus dilatatus Westwood (both sexes). If these particular reductions are discounted the remaining features of E. nitens correspond well with diagnosis of the genus Idiotypa . We therefore consider E. nitens is simply a highly derived species of Idiotypa and Eunuchopria Szabó, 1961 is therefore a junior synonym of Idiotypa Förster, 1856 .

Unfortunately the diagnostic characters of the species of Idiotypa are not universal in all parts of the Palaearctic region. The key below works well for the fauna of Europe (including the European part of Russia), Siberia and Russian Far East. While antennal characters of female I. maritima and I. mariae are difficult to appreciate, in combination with characters of the mesopleural sculpture and body colour, they can be used to make reliable determinations, however in Japan no combination of characters is consistent for species recognition.

Figures

FIGURES 16‒21. Idiotypa nitens (Szabó, 1961), female: 16) head, mesosoma and base of metasoma in dorsal view (scale bar = 0.2 mm); 17) head, mesosoma and base of metasoma in lateral view; 18) S2 (scale bar = 0.2 mm); 19) face (scale bar = 0.2 mm); 20) whole insect in lateral view (scale bar = 0.5 mm); 21) antenna, ventral view (scale bar = 0.2 mm).