Caconeura verticalis delia ( Karsch )

Lieftinck, M. A., 1935, A Synopsis of the Odonata (Dragonflies) of Sumatra, Miscellanea Zoologica Sumatrana 1, pp. 1-23 : 9

45. Caconeura verticalis delia ( Karsch)

(= arba Krug.. = verticalis Albarda. = delia risi Schmidt. = verticalis karnyi Laidlaw). -

Eastcoast Gvt.: Deli. Bindjei Est. ( Karsch); Soekaranda ( Kruger); Soengei Krio Est.. van der Meer Mohr leg. Westcoast Res.: Tanahdatar & Loeboektarap ( Albarda); Padangsche Bovenlanden ( Ris); Lake Singkarak ( Schmidt). S. Lampoeng Res.: 54 ♂, 6 ♀. Mt. Tanggamoes. Gisting. 4-500 m. Dec. 24-30. 1934. Wailalaan & Waiberah . common. Author leg . Sehmidt has correctly placed C. arba Krug. as a synonym of delia Karsch. but he is evidently wrong in considering delia specimens of N. E. Sumatra (Deli). S. Sumatra (Benkoelen) and Simaloer Is. as racially distinct from his delia risi of E. Sumatra and the Westcoast Res. (Padangsche Bovenl.). This confusion is largely due to the fact that Schmidt erroneously places Bindjei, Soekaranda, and even Deli (!) in South Sumatra. instead of in the northeast part of the island. As hinted at in a previous paper ( Lieftinck. M. Z. S.. LIX. 1931). there is much evidence of delia being the same species as verticalis. whose genital s tructures are exactly identical in the ♂ as well as in the ♀ sex. Anticipating a revision of the oriental Protoneurinae, it may be noted here that the ♀ of verticalis. described by de Selys in 1886 does not belong to that species, and hence I have followed Forster. who placed delia as a subspecies of verticalis. As is well brought out by our series of delia from the Lampoengs, this race shows considerable variability, and different forms, including risi, exist in the same locality. For similar reasons I regard karnyi and other specimens from Nias I, as being identical with delia. As the colour-differences between verticalis and delia are yet quite obvious. I see no objection to giving delia subspecific rank. Perhaps C. humeralis Selys will prove to be a distinct species.