Pergesa acteus (Taxonomy)
Transferred to Pergesa by Walker, 1856, List Specimens lepid. Insects Colln Br. Mus.8: 153; then to Rhyncholaba by Rothschild & Jordan, 1903, Novit. zool.9 (suppl.): 789. Returned to Pergesa by Tutt, 1904, Nat. Hist. Br. Lepid.4: 144. Erroneously returned to Rhyncholaba by d'Abrera, [1987], Sphingidae Mundi: 198, then back to Pergesa by Bridges, 1993, Cat. Fam. Gen. Spec. Sphingidae of the World: VIII.19. Implicitly transferred to Rhyncholaba by Zhu & Wang, 1997, Fauna Sinica Insecta 11: 380. Implicitly returned to Pergesa by Kitching & Cadiou, 2000, Hawkmoths of the world: 61.
An unmistakable species; superficially similar to Theretra nessus but smaller and lacking the long golden subdorsal abdominal patches of that species and with a pale grey dorsal band running longitudinally from the anterior edge of the thorax to the tip of the abdomen.Forewing apex strongly falcate. Upperside of thorax and abdomen with a conspicuous pale grey longitudinal band. Forewing upperside with a characteristic diffuse green band running obliquely across from the inner margin to the apex; discal spot a minute but conspicuous black dot. Uncus similar gradually narrowed apically, truncate, feebly sinuate, the edge rounded.Gnathos as long as uncus, gradually tapered to a point, apex somewhat upcurved.Valve with more than 12 large stridulatory scales.Harpe elongate, subcylindrical, horizontal, weakly curved, apex concave dorsally, slightly spatulate in dorsal view.Aedeagus with single dentate process.