Procloeon (Oculogaster) cylindroculum Kimmins 1956

Kluge, Nikita J., 2020, Review of Oculogaster Kluge 2016 (Ephemeroptera, Baetidae, Procloeon Bengtsson 1915), Zootaxa 4820 (3), pp. 401-437 : 405

Procloeon (Oculogaster) cylindroculum Kimmins 1956

Procloeon cylindroculum Kimmins 1956: 865 (♂ imago); Kimmins 1960: 341 (♀ imago, ♂ and ♀ subimagines); Kimmins 1971: 312 (holotype); Gillies 1997: 247 (♀ imago, larva).

Cloeon cylindroculum: Demoulin 1970: 55 ; Gillies 1979: 155 (♂ imago); Gillies 1980: 145 (♂ and ♀ imagines, larva); Gillies 1985: 8.

Procloeon (Oculogaster) cylindroculum: Kluge 2016: 495 (larva, subimago, ♂ and ♀ imagines).

Material examined ( ZIN). TANZANIA: Njombe Region, sources of Great Ruaha river above Mfumbi (8 km E Chimala) 8°52′S, 34°05′E, 26.VII–3.VIII.2016, coll. N. Kluge & L. Sheyko: 3 L-S-I ♂ , 1 L-S ♂, 4 L-S-I ♀, 5 L-S ♀, 16 larvae; 13–16.VIII.2017, coll. N. Kluge & L. Sheyko: 1 L-S-I ♀, 5 larvae. ZAMBIA, UGANDA, MALI – see Kluge 2016.

Material newly reported: ZIMBABWE: Province Matabeleland North, Zambezi River, Victoria Falls , 24.IV.1993, coll. P.C. Matteson: 1 ♀ imago (deposited in the Purdue University Research Collection, USA; personal communication by Thomas Klubertanz).

Additional characters. Abdominal terga of larva have not only simple (i.e. non-bifurcate) setae, but also one pair of bifurcate setae near midlength of each tergum VIII–IX and one pair of bifurcate setae near posterior margin of each tergum VII and IX (as in Figs 3 and 48 ). On tergum IX the row of denticles is interrupted medially, behind a pair of submedian setae (as in Fig. 47 ). Other characters as formerly described ( Kluge 2016).

Distribution. Tropical Africa.

Comment. Larvae inhabit rivers with significant water current, but keep themselves in the places with nearly stagnant water; in the mountain portion of Great Ruaha many larvae were found in a pool formed by integral rock and separated by this rock from the current.

In the previous paper ( Kluge 2016), I wrote that since nobody compared specimens of the tropical Procloeon cylindroculum with specimens of the South African form described by Barnard (1932) as « Austrocloeon africanum », most probably these forms belong to one and the same species. Now the new reared material from South Africa allows to make such comparison and conclude that these two forms clearly differ one from another by coloration of winged stages; that fact allows them to be treated as two different species, P. (O.) cylindroculum and P. (O.) barnardi sp. n. (see below).

Figures

FIGURES 1–7. Procloeon (Oculogaster) barnardi sp. n. 1–6, male larva ready to moult to subimago: 1–2, larval cuticle detached from thorax and abdomen; 3, fragment of abdomen (arrows show bases of bifurcate setae similar to Fig. 48); 4, intact specimen (IV–IX, abdominal segments); 5, extracted subimaginal thorax; 6, extracted subimaginal abdomen; 7, same, female.

FIGURES 43–48. Larval exuviae of Procloeon (Oculogaster) niger sp. n. 43–44, caudalii; 45, abdomen; 46, half of pronotum and mesonotum; 47, male uromeres IX–X; 48, fragment of abdominal tergum VIII (arrow shows long bifurcate seta near midlength) (43–46, holotype).