Parapimpla rhenana Theobald, 1937

Spasojevic, Tamara, Broad, Gavin R. & Klopfstein, Seraina, 2022, Revision of 18 ichneumonid fossil species (Hymenoptera, Ichneumonidae) highlights the need for open nomenclature in palaeontology, Fossil Record 25 (1), pp. 187-212 : 187

Parapimpla rhenana Theobald, 1937 stat. rev.

Fig. 19

Material.

Holotype (part F1321/1 and counterpart F1321/2) examined at the NMBA.

Stratum.

Kleinkembs, Pays de Bade, Haut-Rhin, France. Early Oligocene (Rupelian), 33.9-28.4 Ma.

Description.

Sex unclear. Dorsal aspect of head, base and some fragments of antennae, dorsolateral view on mesosoma, partial fore wings (one of which is folded longitudinally), partial hind wing and legs, and first five tergites visible. Body length unclear as tip of metasoma is missing, but probably a bit more than 10 mm.

Dark brown on head and mesosoma, orange-brown legs, wing veins, T1, and basal spots on T2-T5, remainder very light brown or yellow.

Head short, with short gena, occipital carina well developed and evenly rounded above. Antenna only partly preserved, scape and pedicel of average dimensions; first flagellomere 6 × as long as wide, the few other visible fragments showing rather elongate flagellomeres. Mesosoma partly crushed, with lighter parts and of normal dimensions; mesoscutum rather long, front margin truncated and prominent, with an indication of a long, converging notaulus, with a light mark in middle; propodeum with pleural, lateral longitudinal and at least partial lateromedian longitudinal carinae, transverse carinae probably present but a bit unclear. Fore wings well preserved, 8.3 mm, but left fore wing longitudinally folded on itself; pterostigma 4.6 × as long as wide, brown with a light base; areolet large and quadrate, almost rhombic, with veins r-rs and 4Rs meeting at its anterior end in ~110° angle; 2m-cu very short and probably with a single bulla anteriorly; cell 2R1 very long (3.5 ×); 1M somewhat curved just before it meets M + Cu. Hind wing only partially preserved, cell R nearly complete; 1Rs almost 3 × longer than rs-m. Hind legs partly preserved, elongate, femur more than 4.5 ×; tibia 9.5 × longer than wide. Metasoma only partly preserved; T1 narrow anteriorly and evenly tapering posteriorly, almost twice as long as wide at apex, without distinct division into petiole and postpetiole; T2 subquadrate; T3 and T4 transverse, each with light colouration and brown paired marks near base.

Interpretation.

This fossil has a very elongate and narrow T1, which does not occur in Pimplinae . The poor preservation, especially of the wing venation and tip of the metasoma, makes a clear attribution of this genus to any of the extant subfamilies challenging. If the shape of T1 is as preserved, then Ctenopelmatinae would be a good match, as they also often have similar wing venation. Similar T1 also occurs in some Banchinae , Cremastinae and Campopleginae . However, we can rule out Banchinae based on the presence of longitudinal carinae on the propodeum, and Cremastinae and Campopleginae can be discounted based on the wing venation. Thus, we move this monotypic genus to Ctenopelmatinae .

Figures

Figure 19. Parapimpla rhenana Theobald, 1937 stat. rev. A. Photograph of the holotype taken at NMBA; B. Our interpretative drawing of the fossil. Thicker lines indicate outlines of body structures, thinner lines show characters inside these outlines, and dotted lines represent uncertain interpretations.