Grylloidea, Laicharting, 1781

Schubnel, Thomas, Desutter-Grandcolas, Laure, Garrouste, Romain, Hervet, Sophie & Nel, André, 2020, Paleocene of Menat Formation, France, reveals an extraordinary diversity of orthopterans and the last known survivor of a Mesozoic Elcanidae, Acta Palaeontologica Polonica 65 (2), pp. 371-385 : 372

Grylloidea gen. et sp. indet.

Fig. 1 .

Material.—MNT NEL 1681 (small adult female with well-developed ovipositor), Menat, Paleocene.

Measurements.—Fore femur 2.8 mm long; fore tibia 3.0 mm long; hind femur 5.0 mm long, 2.0 mm wide; hind tibia 4.8 mm long; ovipositor 7.5 mm long.

Description.—Body densely covered with strong setae ( Fig. 1A 1 ). Head triangular with small, protruding eyes; last three joints of maxillary palpi about equal in length; joint 5 slightly, but regularly widened toward apex; apex truncated apically; scapes and antennae not visible; pronotum small, with shape not clear; wings and tegmina apparently lacking; right fore leg and both hind legs present; mid legs lacking; right fore tibia with an outer tympanum, elongate, probably obliterate, not slit-like; inner tympanum not visible; at least two apical spurs, one ventral and one dorsal; basitarsomere I long, but less than half tibia I length; both hind legs well-preserved; hind femora thick at base, not filiform at apex; hind tibiae shorter than hind femora; with three inner apical spurs, the dorsal the longest ( Fig. 1A 2 ); outer apical spurs not visible; at least two inner and two outer subapical spurs, short; no spine above and between subapical spurs; basitarsomeres III longer than half hind tibiae; with several dorsal (inner, outer?) spines; tarsomeres II cylindrical, not flattened; tarsomeres III with a pair of claws; abdomen. Cerci long and thin, with very long setae; ovipositor longer than hind femora; apex short, triangular, no ornamentation visible.

Remarks.—The shape of the hind legs, with three-joint tarsi, that of the ovipositor and the presence of acoustic tympanum on fore tibia attest that this fossil belongs to Grylloidea .

Figures

Fig. 1. Orthopteran Grylloidea sp., MNT NEL 1681 from Paleocene of Menat, France. A. Habitus. B. Apex of hind tibia.

Fig. 2. Grylloidean orthopteran Menatgryllus longixiphus gen. et sp. nov., holotype, MNT-1053 from Paleocene of Menat, France. Photograph of habitus A1), reconstruction of hind tibiae and tarsus (A2, left; A3, right).