Prionaspidion Lepeco & Melo, 2022

Lepeco, Anderson, Barbosa, Diego N. & Melo, Gabriel A. R., 2022, A remarkable new family of stinging wasps from the Cretaceous of Myanmar and China (Hymenoptera, Aculeata), Journal of Hymenoptera Research 94, pp. 163-190 : 163

† Prionaspidion Lepeco & Melo gen. nov.

Type species.

† Prionaspidion brevidens Lepeco & Melo, sp. nov.

Included species.

† Prionaspidion brevidens Lepeco & Melo, sp. nov., † Prionaspidion nanus Lepeco & Melo, sp. nov.

Diagnosis.

Species in the new genus are characterized by the combination of the following characters: absence of enclosed cells in the forewing; enlarged head, which is far wider than the mesosoma; vertex flat in frontal view; lower margin of lateral ocelli well-above upper eye level; and metasoma shortened, with telescopic segments. Additional diagnostic features are the relatively small eyes in comparison to the head size and the tibial spur formula: 1-1-1 or apparently 1-0-1. Females have simple tarsal claws, while the only known male has bifid claws. In the type species, it seems that the apical portion of the third valvulae is permanently exposed.

Description.

Head. Enlarged, far wider than mesosoma; prognathous. Apical margin of clypeus completely filled with indentations or denticles; disc of clypeus about as large as compound eye, almost flat. Frons wider than eye length, flat. Frontal line indicated as shallow sulcus near mid ocellus. Compound eye relatively small, bulging, glabrous. Vertex flat in frontal view; extending behind lateral ocelli for at least 1.5 times length of ocellar triangle. Lower margin of mid ocellus near upper tangent of compound eye. Lower margin of lateral ocelli well-above upper eye tangent. Antenna. F1-F8 about twice as long as maximum width; F1 about as long as F2. Mesosoma. Pronotal collar relatively long, at least as long as mesoscutum; anterior surface of pronotum somewhat rounded in dorsal view, with transverse sulcus at mid-height; surface near posterior edge without transverse depression. Surface of mesoscutum between notauli flat, at the same level as lateral surfaces. Mesepisternum with a shallow transverse sulcus above mesepisternal pit. Metanotum with few short carinae on sublateral surfaces. Propodeum with box-like aspect, posterior slope abrupt; dorsal surface not depressed between spiracles. Legs. Arolia not enlarged. Tibial spur formula 1-1-1 or apparently 1-0-1. Forewing. Without enclosed cell. Veins C and Sc+R completely fused. Pterostigma vestigial. Vein M+Cu nebulous. Vein cu-a absent. Distal portion of vein Cu absent. Vein A spectral. Hindwing. Vein C present, nebulous. Vein A absent. Metasoma. Short, far shorter than lengths of head and mesosoma combined; segments telescoped within each other.

Etymology.

The name is derived from Ancient Greek, being a combination of prion, which means “saw”, and aspidion, meaning "small shield", in reference to the clypeus with a series of denticles along its apical margin. It is a neuter name.