Lectotype designations of new species of hydroids (Cnidaria, Hydrozoa), described by C.M. Fraser, from Allan Hancock Pacific and Caribbean Sea Expeditions

Hydroids of the Allan Hancock Pacific Expeditions, and those of the Allan Hancock Caribbean Sea Expedition, were examined by Charles McLean Fraser in a series of reports published between 1938 and 1948. A total of 159 new nominal species was described from material collected in the eastern Pacific between Peru and southern British Columbia. Accounts of an additional five nominal species were based on specimens from the southern Caribbean Sea. No valid holotypes were designated in accordance with provisions of the International Code of Zoological Nomenclature for any of these taxa. The purpose of this report is to establish an objective standard for each species, and to promote stability of nomenclature in Hydrozoa, by designating lectotypes for these taxa, or in a few cases by recognizing a holotype by monotypy, based largely on specimens in the Allan Hancock Hydroid Collections at the Santa Barbara Museum of Natural History. One lectotype colony is in the C.M. Fraser Hydroid Collection at the Royal British Columbia Museum. Paralectotype material was also designated for most of the species. Plumularia irregularis Fraser, 1948 is referable to the genus Nemertesia Lamouroux, 1812, as are Antennularia irregularis Quelch, 1885 and Antennularia irregularis Fraser, 1938a [=Nemertesia fraseri Ramil and Vervoort, 1992]. To avoid secondary homonymy we adopt the replacement name Nemertesia hancocki, nom. nov., for Plumularia irregularis Fraser, 1948. The specific name honors George Allan Hancock, philanthropist. Also referable to Nemertesia are Antennularia mutabilis Fraser, 1948 and Plumularia mutabilis Fraser, 1948, where they become homonyms. Nemertesia anomala, nom. nov., is proposed as a replacement name for Plumularia mutabilis Fraser, 1948.