Indocloeon (Hindocloeon) longistylus ( Demoulin 1969 ) Kluge & Suttinun, 2020

Kluge, Nikita J. & Suttinun, Chanaporn, 2020, Review of the Oriental genus Indocloeon Müller-Liebenau 1982 (Ephemeroptera: Baetidae) with descriptions of two new species, Zootaxa 4779 (4), pp. 451-484 : 479

Indocloeon (Hindocloeon) longistylus ( Demoulin 1969) comb. n.

( Fig. 105 )

Cloeon longistylus Demoulin 1969: 231 (♂ imago).

Comments. This species was briefly described based on 3 male imagines. It was placed in the genus Cloeon Leach 1815 , which at that time represented an artificial group and comprised various species with single marginal intercalaries on the fore wing and no hind wings. The structure of genitals figured in the original description ( Demoulin 1969: fig. 7b) clearly testify that this species belongs to Indocloeon s. l. Judging by this figure, the distal (3rd) segment of the gonostylus is as long as the proximal (1st +2nd) segment ( Fig. 105 ), and this distinguishes Indocloeon longistylus from other known species, whose distal segment is shorter than the proximal segment, both in the imaginal and subimaginal stages ( Figs 101–104 ).

Distribution: Balabac and Palawan Islands of the Philippines ( Demoulin 1969).

Figures

FIGURES 101–105. Male genitals of Hindocloeon. 101, imaginal genitals of Indocloeon (Hindocloeon) continentale sp. n. (penis dotted; 1+2, proximal segment of gonostylus; 3, distal segment of gonostylus; gv-d, distal portion of gonovectis; gv-p, proximal portion of gonovectis; m.d, dorsal muscle of penis; m.gs, gonostylar muscle; m.gv, gonovectal muscle; m.s., median sterno-styligeral muscle); 102, their subimaginal exuviae; 103, subimaginal gonostyli of I. (H.) sp. «Vietnam»; 104, subimaginal gonostyli of I. (H.) sp. «Java»; 105, imaginal genitals of I. longistylus (after Demoulin 1969).