Tumidistephanus epimetheus Ge & Tan, 2025

Ge, Si-Xun, Ren, Li-Li & Tan, Jiang-Li, 2025, The mid-Cretaceous crown wasp genus † Tumidistephanus Ge & Tan: discovery of the first male and a new species (Hymenoptera, Stephanidae), ZooKeys 1248, pp. 53-59 : 53-59

† Tumidistephanus epimetheus Ge & Tan sp. nov.

Figs 1 , 2 , 3

Material examined.

Holotype • ♂, Hukawng Valley , Tanai township, Myitkyina district of Kachin state, Myanmar) (BFU).

Etymology.

The species name is derived from Epimetheus, the younger brother of Prometheus in ancient Greek mythology.

Diagnosis.

Head subcircular, with seven distinct coronal teeth; forewing with 1 - M approximately 0.5 × as long as 1 - Rs and slightly curved; veins Rs + M and 1 Cu parallel; vein 2 Rs + M nearly absent, with veins 2 - Rs and the apical abscissa of M distinctly unconnected. Metafemur markedly robust, with two prominent and five medium-sized teeth.

Description.

Holotype. • ♂, length of body about 3.25 mm (excluding antennae). Forewing length about 1.78 mm.

Head. Antenna filiform, elongate, composed of at least 19 flagellomeres; first flagellomere elongated and robust, second flagellomere comparatively short. Head broadly subcircular; frons coarsely obliquely to transversely rugose near anterior coronal tooth; vertex with seven distinct tubercles, transversely carinate posterior to the anterior coronal teeth, carinae not extending to the occipital carina. Occipital carina obsolete; temple moderately expanded posterior to compound eye.

Mesosoma. Pronotum short and robust, lacking distinct pronotal fold; neck, medial and posterior region of pronotum aligned in profile. Pronotum and mesonotum densely foveate; mesopleuron laterally with oblique transverse rugosity and ventrally with large foveae.

Wings. Forewing: vein 1 - M 0.5 × as long as 1 - Rs and slightly curved, 1.5 × as long as vein m-cu; vein 2 - Rs 3.4 × as long as vein r-rs; vein r-rs ends 0.3 × length of pterostigma; vein A incomplete, reaching only reach at 1 cu-a; vein Rs + M and 1 Cu parallel; vein 2 Rs + M almost absent, with no connection between veins 2 - Rs and the distal segment of M. Hindwing with vein Cu-a and vein M + Cu lacking.

Legs. Fore and mid legs with their femora and tibiae flattened and expanded. Metacoxa robust, spindle-shaped, ventrally with two rows of tubercles; metafemur coriaceous, extremely swollen medially, nearly oval in profile. Metafemur with two large and five medium-sized teeth (two intercalated between the large teeth, three discal to the apical large teeth); metatibia 1.2 × as long as metafemur, with basal narrow portion 0.9 × as long as apical broadened part; metatarsus with five tarsomeres; basitarsus 4.3 × as long as wide.

Metasoma. Metasoma with eight segments. First tergum and sternum not fused laterally, Tergite I rather robust, about 0.9 × as long as tergite II.

Female. Unknown.

Figures

Figure 1. † Tumidistephanus epimetheus Ge & Tan, sp. nov. holotype ♂. A. Head, dorsal-lateral view; B. Head, ventral view; C. Mesosoma, dorsal-lateral view; D. Wings.

Figure 2. † Tumidistephanus epimetheus Ge & Tan, sp. nov. holotype ♂. A. Metasoma, lateral view; B. Hind leg, lateral view; C. Hind coxa, ventral-lateral view; D. Hind femur, lateral view; E. Hind tibia, lateral view; F. Hind tarsus, lateral view; G. Male genitalia.

Figure 3. Tumidistephanus epimetheus Ge & Tan, sp. nov. holotype ♂.