Indocloeon (Hindocloeon), 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 : 479-481

Indocloeon (Hindocloeon) sp. « Java »

( Figs 104 , 111 , 115–118 )

Material examined ( ZIN). INDONESIA, Java , 15 km NW Parigaran , S7°38’18”, E108°31’48”, h= 99 m. 29.I.2018, coll. S. Melnitsky & V. Ivanov: 2 S ♂, 2 S ♀ .

Descriptions. Subimaginal cuticular colouration. Most part of cuticle colourless, lateral sclerite of parascutellum and posterior part of postsubalar sclerite brown.

Male subimago ( Figs 117–118 ). Turbinate eyes red. Antenna: distal part of scapus with hypodermal pigmented spots on lateral and median sides; distal part of pedicellus with hypodermal pigmented spots on lateral and median sides (as in Fig. 92 ) [see Hindocloeon (9)]. First abdominal segment with pair of brown hypodermal spots just ventrad of metathoracic postnotum ( Fig. 117 ) [see Hindocloeon (10)]. Other abdominal terga either without pigmentation, or terga VII–IX with brown hypodermal dot at middle ( Fig. 118 ).

Female subimago ( Figs 115–116 ). Antennae as in male. Pronotum with three pairs of small, contrasting, brown hypodermal markings on lateral parts: zigzag anterior, elongate postero-median and triangular postero-lateral ones. Mesothorax with small, brown hypodermal spots on pleura. Abdomen with dark, lateral tracheal trunks; segment I with pair of brown hypodermal lateral spots just ventrad of metathoracic postnotum; each segment II–VII with fol- lowing contrasting brown hypodermal maculae: lateral side of tergum with longitudinal triangular macula (widest anteriorly) and darker brown dot near antero-median angle of this macula; lateral side of sternum with longitudinal macula of peculiar shape ( Fig. 115 ).

Egg ( Fig. 111 ). Oval, about 0.15 mm length. Chorion with very fine rugosity.

Dimension. Fore wing length (and approximate body length) 3.5 mm.

Comments. Male subimagines are determined as belonging to Indocloeon s. l. based on the peculiar structure of gonostyli ( Fig. 104 ). Female subimagines are determined as belonging to the same species based on equally colourless cuticle and the same structure of middle and hind legs as in males. Belonging of the female subimagines to the genus Indocloeon s. l. is proven by the absence of the patella-tibial suture on fore legs. This species differs from I. (H.) longistylus by having a relatively longer proximal segment of the gonostylus even in the subimaginal stage ( Fig. 104 ). Male and female subimagines differ from the subgenus Indocloeon by the absence of reddish stripes on posterior margins of abdominal terga. The male differs from I. (H.) indonesiae , I. (H.) continentale and I. (H.) sp. « Vietnam » by the shape of the gonostylus. The female subimago differs from I. (H.) indonesiae , I. (H.) continentale and I. (H.) sp. « Vietnam » by the peculiar shape of brown maculae on abdominal terga and on the pronotum ( Figs 115–116 ).

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).

FIGURES 106–111. Eggs of Hindocloeon. 106–108, Indocloeon (Hindocloeon) continentale sp. n.: 106–107, specimen from Erawan (Thailand); 108, specimen from Erumeli (India). 109–110, Indocloeon (Hindocloeon) indonesiae; 111, Indocloeon (Hindocloeon) sp. «Java».

FIGURES 115–118. Indocloeon (Hindocloeon) sp. «Java». 115–116, female subimago; 117–118, male subimago.

FIGURES 91–95. Indocloeon (Hindocloeon) continentale sp. n. 91, fragment of subimaginal exuviae with postsubalar sclerite; 92, antennae of male imago; 93, male imago; 94, its metathorax and base of abdomen; 95, male subimago (arrow shows brown hypodermal spot just ventrad of metathoracic postnotum).