Trirogma Westwood, 1841

Liu, Zhi-Zhi, Ma, Li & Li, Qiang, 2024, One new species and one new record of the genus Trirogma Westwood (Hymenoptera: Ampulicidae) in China, with a key to the world species, Zootaxa 5538 (5), pp. 448-456 : 449

Genus Trirogma Westwood, 1841

Trirogma Westwood, 1841: 152 .

Type species: Trirogma caerulea Westwood , by monotypy.

Trirhogma Agassiz, 1847: 378 . Emendation of Trirogma Westwood, 1841 .

Diagnosis. Surface of body often with bright metallic color. Two antennal sockets close together, covered above base by a plateau-like frontal lobe, frontal lobe with one longitudinal groove medially, making edge ‘U’ shaped. Pronotal collar often with tubercles on both sides. Pronotum with several oblique carinae laterally. Posterior lateral corner of scutum strongly reflexed bordering a depressed area, parapsidal lines present; admedian lines absent; notaulus long and extending to hind margin. Tip of marginal cell terminated in fore wing margin, jugal lobe of hind wing small. Claws unidentate. Metasomal petiole short; in general, only metasomal segments I-III visible in males and IV-VII often be hidden ( Bohart & Menke, 1976). Fore wing of female with vein M+Cu diverging before crossvein cu-a, in male vein M+Cu diverging at crossvein cu-a.

Biology. Most species of Trirogma prefer to hunt the genus Periplaneta ( Pu & Zhou, 1989) . Field observations have revealed that adults primarily feed on nectar, honeydew, and rotting fruits. Females often search for prey in areas with grasses, fallen leaves, and dead trees, and they occasionally venture into human settlements. The hunting behavior of this genus is particularly unique; upon locating their prey, they quickly give chase and attempt to bite the prey’s leg or cercus. After biting the prey, they will bend forward and stretch the metasoma to sting their prey under the head and mesosoma to paralyze them. This hunting behavior closely resembles that of Dolichurus .

Distribution. China (Yunnan, Zhejiang, Hong Kong, Taiwan), India, Indonesia, Singapore, Sulawesi, Iran, Iraq, Turkey, Saudi Arabia, United Arab Emirates, Sri Lanka, Malaysia ( Bohart & Menke, 1976; Pulawski, 2024).