Stylogomphus malayanus Sasamoto, 2001

Chainthong, Damrong, Sartori, Michel & Boonsoong, Boonsatien, 2020, Stylogomphus thongphaphumensis (Odonata: Anisoptera: Gomphidae), a new gomphid dragonfly and the first record of S. malayanus Sasamoto, 2001 from Thailand, Zootaxa 4763 (2), pp. 231-245 : 240

Stylogomphus malayanus Sasamoto, 2001

( Figs 40–43, 45, 47 )

Material examined. THAILAND: 1♂ adult and its exuvia (reared specimen), Khlong Khanan, Bang Saphan, Prachuap Khiri Khan province, 11°14′30.98″N 99°21′15.6″E, 91.8 m a.s.l., larva collected on 10.IV.2019, adult emerged on 23. IV. 2019, D. Chainthong leg.

Diagnosis. Sasamoto (2001) recorded male and female specimens of S. malayanus and known larvae from the Malay Peninsula. In this study, we reared the Stylogomphus larva until the emergence of the male adult. We identified the specimen as S. malayanus . This represents the first record of this species from Thailand. Stylogomphus malayanus looks similar to S. delicatus and S. inglisi , although the cerci have a double latero-ventral tooth, and the epiproct is not nearly as deeply incised in ventral view. In addition, the male of S. malayanus can be distinguished from other species by the structure of the anal appendages ( Figs 40–42 ): 1) cerci creamy white, basal 1/3 somewhat thick and ventrally and basally black, tapering to the apex, with two double latero-ventral teeth; and 2) epiproct black, extending relatively straight and not diverged apically, cleft for about half of the length ( Sasamoto 2001, 2004; Kompier 2017).

Figures

FIGURES 40–42. Male anal appendages of Stylogomphus malayanus from Thailand, (40) dorsal view; (41) lateral view; (42) ventral view. Scale =1 mm.

FIGURES 43–48. Comparison of larvae of two Stylogomphus spp.: S. malayanus (43, 45, 47), S. thongphaphumensis sp. nov. (44, 46, 48): (43, 44) antenna in dorsal view; (45, 46) abdomen in dorsal views; (47, 48) prementum in ventral view. Scale = 1 mm.