New mayfly species of Caenis and Kalimaenis from Thailand and descriptions of two new genera of the subfamily Caeninae (Ephemeroptera: Caenidae)

Abstract

Abstract Six new species of Caenis from Thailand are described herein: Caenis ludovici n. sp., Caenis nasuta n. sp., Caenis longiforcipata n. sp., Caenis karenae n. sp., Caenis obtusostilata n. sp. and Caenis acutostilata n. sp., as well as the larvae of Caenis picea Kimmins, 1947 and Caenis ulmeriana Malzacher, 2013, which were so far only known as males. Furthermore, a new species of the genus Kalimaenis, Kalimaenis procera n. sp., is described. Also described from the same area are two new genera of the subfamily Caeninae: Elatosara n. gen. (Type species Elatosara phanomensis n. sp.) most probably belongs to the tribe Clypeocaenini; Thainis n. gen. (Type species Thainis kalimaenoides n. sp.), is classified within the tribe Caenini. The phylogeny of the new genera is discussed. A larval key to the Caeninae from Thailand is provided and the key to the male Caenis of the Oriental region (Malzacher 2015) is replenished.