Pteropilosa lailarabanorum, Blaeser, Marcel, Krogmann, Lars & Peters, Ralph S., 2015

Blaeser, Marcel, Krogmann, Lars & Peters, Ralph S., 2015, Two new fossil genera and species of Cerocephalinae (Hymenoptera, Chalcidoidea, Pteromalidae), including the first record from the Eocene, ZooKeys 545, pp. 89-100 : 92-94

Taxon classification Animalia Hymenoptera Pteromalidae

Pteropilosa lailarabanorum sp. n.

Diagnosis.

See genus.

Description.

Female: total body length 1.62 mm; length of head 0.32 mm, of mesosoma 0.64 mm, of metasoma 0.86 mm. Body without metallic luster. Head: height 0.35 mm. Shape of head round (globose) and head smooth, without sculpture; no depression on face; mandibles small (not measurable). Eyes rather big and slightly egg-shaped, 0.22 mm high and 0.19 mm wide. Intertorular prominence tooth-shaped and positioned between toruli, but slightly below level of toruli. Antennae: inserted well above ventral margin of eyes (in upper third of eyes); scape length 96 µm, pedicel length 48 µm, pedicel rather short and stout; funicle 6-segmented. First funicular segment wider than long, F2 longer than wide. F3-F6 wider than long, distally broadened club-like (F1: length: 33 µm × width: 37 µm; F2: 40 µm × 38 µm; F3: 47 µm × 56 µm; F4: 48 µm × 69 µm; F5: 48 µm × 71 µm; F6: 54 µm × 77 µm); all funicle segments with sensilla. Clava egg-shaped, 0.14 mm long and 81 µm wide. Wings: fore wing disc pilose, without fuscous band. Elongate admarginal setae absent. Fore wing length 1.19 mm and width 0.33 mm; submarginal vein 0.42 mm long, marginal vein 0.33 mm and postmarginal vein 76 µm long, stigmal vein curved, 76 µm long; stigma slightly thickened and uncus visible. Hind wing length 0.98 mm and width 0.23 mm, only two hamuli visible. Legs: length of hind tibia 0.24 mm, hind femur 0.35 mm, hind trochanter 46 µm, hind coxa 0.15 mm. The other legs cannot be measured due to the position of the specimen within the amber. Mesosoma: pronotum, mesoscutum and mesoscutellum completely reticulated. Frenal line clearly visible and foveolate; frenum 0.55 times as long as mesoscutellum. Length of pronotum 0.25 mm, of mesoscutum 0.13 mm, of mesoscutellum 50 µm, of frenum 29 µm. Axillae large, medially connected. Metanotum with distinct foveae; lateral panel of metanotum wide and smooth. Metascutellum thin; not reaching anterior margin of metanotum. Propodeum coarsely reticulated. Metasoma: petiole (Mt1) small, transverse, hardly recognizable. Metasomal tergites Mt2 to Mt9 smooth, Mt2: 0.23 mm, Mt3: 42 µm, Mt4: 0.15 mm, Mt5: 0.13 mm, Mt6: 67 µm, Mt7 0.10 mm, Mt8/9: 70 µm. Ovipositor 0.12 mm (top view) exerted beyond end of gaster.

Taxonomic remarks.

Following the latest available identification key of Krogmann (2013), Pteropilosa lailarabanorum would be determined as Sciatherellus . However, there are distinct differences between the two genera. In addition to the pilose fore wings which are unique in Pteropilosa (Fig. 1B), Sciatherellus differs from Pteropilosa lailarabanorum in having six antennal funiculars that broaden distally, with F3-6 distinctly transverse (Fig. 1D). In contrast, no funicular segment in Sciatherellus is wider than long. The fore wings of Sciatherellus also possess two prominent dark transverse bands that are absent in Pteropilosa , and the stigmal vein is straight in contrast to that of Pteropilosa lailarabanorum , which is distinctly curved (Fig. 1B). The main differences between Pteropilosa and Neocalosoter are the pilose wings, the sculptured mesosoma, and the position of the toruli. In Pteropilosa , the antennae are inserted distinctly above the lower margin of the eyes, at around 2/3 of the height of the eyes (Fig. 1D). In the description of Neocalosoter (by Girault and Dodd in Girault 1915), it is stated that the antennae in this genus are "inserted at mouth border", i.e., below the lower margin of the eyes. However, the position of the toruli in Pteropilosa lailarabanorum is not unique within Cerocephalinae . Sciatherellus , Dominocephala , Muesebeckisia , and Gnathophorisca also have the antennae inserted above the lower margin of the eyes. Muesebeckisia and Gnathophorisca are easily distinguishable from Pteropilosa by their enlarged and conspicuously thickened mandibles. Furthermore, Muesebeckisia and Gnathophorisca share a fuscous band on the fore wing, which is absent in Pteropilosa lailarabanorum . The recently described fossil genus Dominocephala can be distinguished from Pteropilosa lailarabanorum by the elongate mandibles and the set of multiple setae on the lower facial process, both of which are not found in Pteropilosa lailarabanorum . Dominocephala also features a fuscous band on the fore wing not present in Pteropilosa lailarabanorum .

Etymology.

Named after Laila and Raban Ohlhoff, the grandchildren of the private donor.