Overlooked cryptic endemism in copepods: Systematics and natural history of the calanoid subgenus Occidodiaptomus Borutzky 1991 (Copepoda, Calanoida, Diaptomidae)

► We compared morphological and genetic data within the copepod taxon Occidodiaptomus. ► A noteworthy decoupling between morphological and molecular diversity is demonstrated. ► The actual diversity of the genus is overlooked due to its morphological bradytely. ► A phylogeny of the subgenus and its phylogeography are presented. ► The role of morphological vs. molecular evolutionary rates in copepods is discussed.