Newly discovered mayflies from Madagascar have proven to represent a new genus and species of Tricorythidae. Provonshaka n. gen. is described in the larval stage, and compared with the Madagascar genus Manohyphella, which is also shown to be a member of the Tricorythidae. Provonshaka is a member of a phylogenetic lineage that also contains Manohyphella and the southeast Asia genus Teloganella. There are presently three tricorythid genera present in Madagascar, including the distantly relatedTricorythus. Provonshaka thomasorum n.sp. is described from three rivers in Madagascar and is sometimes found cohabiting with Manohyphella keiseri. A diagnostic table giving the differences between Provonshaka and Manohyphella is provided.