Oreiallagma gen. nov. with a redefinition of Cyanallagma Kennedy 1920 and Mesamphiagrion Kennedy 1920, and the description of M. dunklei sp. nov. and M. ecuatoriale sp. nov. from Ecuador (Odonata: Coenagrionidae)

Abstract

In this paper we re-evaluate Cyanallagma Kennedy 1920, which currently includes 15 species, and we address another five species that share diagnostic characters with some of them but are currently placed within Leptagrion Selys 1876, Mesamphiagrion Kennedy 1920, and Telagrion Selys 1876. A new genus, Oreiallagma, is described to include five species originally placed in Acanthagrion Selys 1876, Cyanallagma, and Telagrion. These species are O. thelkterion (De Marmels 1997) (type species), O. acutum (Ris 1918), O. oreas (Ris 1918), O. prothoracicum (Kimmins 1945), and O. quadricolor (Ris 1918). The last stadium larva of O. quadricolor is described. The remaining species currently includedin Cyanallagma are allocated to two separate genera: Cyanallagma sensu stricto and Mesamphiagrion. Cyanallagma sensu stricto comprises southern South American species including the type species, Cyanallagma interruptum (Selys 1876). Mesamphiagrion Kennedy 1920 includes a cluster of species from northwestern South America that are considered congeneric with the type species Mesamphiagrion occultum (Ris 1918). Two new species from Ecuador, M. dunklei and M. ecuatoriale, are described and Argia hebdomatica Navás 1934 is found to be a junior synonym of M. ovigerum (Calvert 1909). Synonymic lists, diagnoses, illustrations, keys, and distribution maps for the three genera are provided.