Hypogena Dejean, 1834

Grey, Luna & Smith, Aaron D., 2020, A matrix-based revision of the genus Hypogena Dejean, 1834 (Coleoptera Tenebrionidae), Zootaxa 4780 (2), pp. 201-258 : 213-216

Hypogena Dejean, 1834

Type species: Tenebrio biimpressus Latreille, 1833 (synonym of Peltis brasilica Perty, 1830 ); by monotypy.

Revised diagnosis: The males of the genus Hypogena are recognizable by a combination of the following characters: supraocular horns present, antennae bearing stellate sensoria ( Fig. 6c,d ), first two protarsomeres with cuticular outgrowth to form spines ( Fig. 7 ), row of cuticular teeth along posterior edge of metasternum ( Fig. 8 ), body distinctly dorsoventrally flattened ( Fig. 10 , lateral). Some species also have a horn arising from the clypeus ( Fig. 36 , male, dorsal). Females similar to males, except lacking produced horns ( Fig. 17 ) and with more prominent punctures on the vertex, frons, and clypeus ( Fig. 21 ).

Redescription: General: color black to reddish brown. Body dorsoventrally flattened. Size: length: 5–10 mm; width: 2–4 mm.

Head. Distance between cardo and eye less than width of cardo. Males with two or three cephalic horns. Mandibles with groove extending to connection point on cranium. Labrum fully setose. Gena not extending laterally past widest point of eye.Antennae 11 segmented; not forming distinct club.Apical six antennomeres bearing stellate sensoria. Mentum trapezoidal, punctate. Eye large, reniform.

Thorax. Pronotum always finely punctate; punctures smaller than eye facet; many coarsely punctate; punctures larger than eye facet. Posterior margin of pronotum bisinuate. Prothorax laterally explanate; anterior apices of prothorax produced anteriorly, sometimes reaching middle of eye. Elytra striate; striae punctate. Epipleuron tapering posteriorly; epipleural fold explanate. Prosternum punctate. Mesepisternum coarsely punctate, unless otherwise indicated. Posterior edge of metasternum with row of cuticular teeth.

Legs. Tarsal formula: 5-5-4. Protibia with first two tarsomeres expanded to form spines. Lateral side of protibia with socketed spines. All tibiae with two apical spurs.

Abdomen. All abdominal segments punctate; punctures on last two ventrites finer than on previous segments. Aedeagus with parameres fused. Female genitalia with coxites highly reduced; spermathecal gland with single apical spermatheca.

Distribution ( Fig. 9 ): USA (AZ, CA, TX and FL) south to Argentina.

Etymology: The name Hypogena is feminine. The name potentially refers to the gena being under the male cephalic horns.

233X magnification with an accelerating voltage of 3kV. 6c. Sensoria of Hypogena tricornis at 1510X magnification with

an accelerating voltage of 4kV. 6d. Terminal segments of antennae of Hypogena tricornis at 110X magnification with an accelerating voltage of 4 kV.

Figures

FIGURE 6: Comparison of antennal sensoria between Hypogena and Tribolium. 6a. Sensoria of Tribolium confusum at 5390X magnification with an accelerating voltage of 3 kV. 6b. Terminal segments of antennae of Tribolium confusum at

FIGURE 7: Tarsal outgrowths on Hypogena tricornis. A. The tarsal outgrowths at 74X magnification with an accelerating voltage of 6 kV. B. The tarsal outgrowths at 224X magnification with an accelerating voltage of 6 kV

FIGURE 8: Posterior edge of metasternum on Hypogena tricornis. 8a. Posterior metasternal gearing at 89X magnification with an accelerating voltage of 4 kV. 8b. Posterior metasternal gearing at 1340X magnification with an accelerating voltage of 4 kV.

FIGURE 9: Distribution of all Hypogena species. Based on 1429 databased specimens.

FIGURE 10: Hypogena akuma, Holotype, male. Dorsal view, lateral view, and labels.

FIGURE 17: Hypogena canaliculata, Lectotype and Paralectotype. Top: dorsal view, lateral view, and labels of Lectotype, male. Bottom: Dorsal view, lateral view, and labels of Paralectotype female.

FIGURE 21: Hypogena cryptica, Holotype and Paratype. Top, Holotype, male: dorsal view, lateral view and labels of male. Bottom, Paratype, female: Dorsal view, lateral view and labels of female.

FIGURE 36: Hypogena tricornis, Holotype and Paratype. Top, Holotype, male: dorsal view, lateral view, and labels. Bottom, Paratype, female: dorsal view, lateral view, and labels. Images obtained from Dr. Johannes Bergsten at The Swedish Museum of Natural History (NHRS).