Tropidopsilus sensu Kieffer 1908
Creators: name: Kawai, Ryoji
name: Chemyreva, Vasilisa
Publisher: name: Zenodo
Year: 2025
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hymenoptera
Diapriidae
Tropidopsilus

description: Genus Tropidopsilus Kieffer, 1908
Tropidopsilus Kieffer, 1908: 358, 366.
Type species Tropidopsilus laticeps Kieffer, 1909.
Masnerolyta Buhl, 1997: 89; syn. nov.
Type species Masnerolyta rubra Buhl, 1997.
Generic diagnosis: head strongly transverse (Fig. 1A); female eye very large and hairy, inner eye orbits border converging in frontal view (Figs 3C, 4C, 7B); tentorial pit always present; malar distance very short, almost as long as diameter of tentorial pit; mandibles widely over-crossing but distinctly shorter than pleurostomal distance (Figs 3C, 4C, 7B); ventral margin of upper frons not defined; flagellum in female 13-merous, in male 12-merous; palpal formula 5-3; epomia well developed below and above of pronotal shoulders (Fig. 1E, white arrows); pronotal suprahumeral sulcus distinct (Fig. 1E, red arrows); mesonotum convex; notauli deep and complete; scutellar disc in lateral view rounded, or with high hump posteriorly (Figs 1E, 3A, 7D); posterior margin of scutellar disc smooth to sculptured (foveolate or sulcate) (Fig. 2A–D); mesopleura with distinct mesopleural pit; subalar bridge distinct (Figs 2C, blue arrow, 3A) to absent (Figs 1E, 4D, 7D); epicnemial pit distinct; epicnemial bridge distinct (Figs 1E, 2C, 3A, 7D) to absent (Fig. 4D); metascutellum with three longitudinal carinae, sometimes medial carina developed as a spinose projection (Fig. 2A–C); median keel of propodeum simple (Figs 1C, 2, 4F, 5A, 7E); plica complete (Fig. 2E) to partly reduced anteriorly (Figs 2F, 2G, 4D); wing development macropterous with wings hyaline; radial cell closed, slightly longer than marginal vein (Figs 1B, 4E, 7H) to distinctly shorter (Figs 1D, 3A); stigmal and postmarginal veins form more or less acute angle; poststigmal vein (Rs2) straight, directed towards the middle of the basalis; postmarginal vein continued far beyond the radial cell; petiole much longer than wide, slightly arched in lateral view, cylindrical to widened anteriorly (Fig. 4A) or slightly swollen medially (Fig. 7F, G); gaster of female more or less compressed with seven visible tergites (T2–T8) and five visible sternites (S2–S6); base of S2 smooth, with arcuate anterior margin (Fig. 1F, G); S6 of female slightly elongate and compressed but not modified; belytoid line developed only on S2 laterally, following sternites smooth laterally (Fig. 1F, G, green arrows); ovipositor longer than T2.
Remarks on the generic synonymy. According to Kieffer's and Buhl's descriptions, Tropidopsilus and Masnerolyta differ by their venation, the posterior margin of the scutellar disc and the structure of the metascutellum (Kieffer 1908, 1909, 1916, Buhl 1997). Based on the Kieffer’s description and photo of the holotype, Tropidopsilus sensu Kieffer has a metascutellar spine and the posterior margin of the scutellar disc is with a transverse depression (Fig. 3B). According to Buhl (1997), the holotype of M. ruber has “scutellum unsculptured posteriorly”, but the holotype specimen has the scutellar disc weakly sulcused posteriorly and the metascutum with a feeble tooth (Fig. 7E). The expanded diagnosis given by Quadros & Brandão (2017) states that the posterior margin of the scutellar disc in Tropidopsilus species is crenulate or smooth. Based on our study of the species mentioned in this article, as well as 6 undescribed species of this genus from Mexico and Brazil, we agree with this statement.
The degree of development of the spinose projection should also be considered as an interspecific or sometimes even intraspecific variation. This is supported by the fact that, the presence or absence of a spine on the metascutellum is quite variable in many genera of Belytinae (Macek 1995), including a number of South American Belytinae and the cosmopolitan genus Aclista, which are morphologically very close to Tropidopsilus.
The type species of the genera Tropidopsilus and Masnerolyta are different in venation. The venation of T. laticeps is shown in Fig. 3A, B. The venation of M. ruber is shown in Fig. 7H. These venations share many similarities, with the only significant difference being the shifting of the stigmal vein a bit apically (Fig. 1B, D). The same range of interspecific variation is known for species of the genus Cinetus Jurine, Miota Förster and Macrohynnis Förster (Macek 1997b).
We believe that these are not reliable features that could be used to define Masnerolyta as a separate genus. Thus, we conclude that Masnerolyta Buhl, 1997, syn. nov., is a junior synonym of Tropidopsilus Kieffer, 1908, and the following species of the former genus Masnerolyta is transferred here to Tropidopsilus: T. ruber (Buhl, 1997), comb. nov.
Distribution. Neotropical region (Brazil and Argentina), Palaearctic region (Japan). Several undescribed species mentioned above were collected in Central America (Mexico).
Biology. Host unknown.
description: Published as part of Kawai, Ryoji & Chemyreva, Vasilisa, 2025, Taxonomy of the genera Tropidopsilus Kieffer, 1908 and Masnerolyta Buhl, 1997 (Diapriidae: Belytinae) with description of a new species of Tropidopsilus from the Palaearctic region, pp. 181-192 in Zootaxa 5627 (1) on pages 182-185, DOI: 10.11646/zootaxa.5627.1.7, http://zenodo.org/record/15325838