A new mayfly species of Caenis from headwater of Zijin Hill (Nanjing, Eastern China) (Ephemeroptera: Caenidae)

Abstract

In the headwaters of several small streams of Zijin hill (Nanjing City) we found a new species of the genus Caenis. Herein this species is illustrated and described as Caenis pycnacantha sp. nov. Its main diagnostic characters include: in nymphs, it has “normal” body shape, each femur has a dark brown subapical marking, and the maxillary palpi have relatively long apical segments. In adults, the forceps have dense setae on the surface and four large spines at the apex and the antennae have a slightly expanded base of the flagellum.