To resolve problems of identity and synonymy of Culex (Melanoconion) taeniopus Dyar and Knab 1907, epanastasis Dyar 1922, crybda Dyar 1924, opisthopus Komp 1926 and pseudotaeniopus Galindo and Blanton 194, a detailed study and comparison of the types and other identified specimens at the U. S. National Museum, and a critical review of the original and subsequent descriptions have been made. As a result of this study, the following actions are taken to stabilize the nomenclature: (1) synonymy of opisthopus with taeniopus, (2) synonymy of pseudotaeniopus with epanastasis, (3) resurrection of crybda from the synonymy of epanastasis and (4) recognition and description of pedroi n. sp. for the Panamanian population previously called taeniopus Dyar and Knab by Galindo (1969). A summary of important diagnostic features of the adults and male genitalia of the above species are presented in provisional keys. All stages of pedroi are described and illustrated and its distribution and bionomics are summarized.