Rhithrogena (Paperback)

High Quality Content by WIKIPEDIA articles! Rhithrogena is a genus of mayflies in the family Heptageniidae. Heptageniidae (Synonym: Ecdyonuridae) is a family of mayflies with around 500 described species with a mainly Holarctic distribution. These are generally rather small mayflies with two long tails. The wings are usually clear with prominent venation although species with variegated wings are known. As in most mayflies, the males have large compound eyes but not divided into upper and lower parts (the group is sometimes referred to as flat-headed mayflies).