The adults of both sexes, pupa and 4th stage larva of Culex (Melanoconion) adamesi, a new species from Panama are described and illustrated. Its affinity with pedroi Sirivanakarn and Belkin 1980, crybda Dyar 1924 and epanastasis Dyar 1921, as interpreted by Sirivanakarn and Belkin (1980) is discussed. The distribution, bionomics and medical importance are summarized.