Revision of Hydroides Gunnerus, 1768 (Polychaeta: Serpulidae) from the Western Atlantic region

A taxonomic revision of the Hydroides species (Polychaeta: Serpulidae) from the Western Atlantic Region is presented. Twenty-six taxa are described, including a comparison between four species with ‘winged’ verticil spines: Hydroides alatalateralis, H. elegantulus, H. floridanus and H. spongicola, between two forms of the H. mongeslopezi complex, and between two forms of the H. brachyacanthus complex. Three widespread species are recorded: H. dianthus, H. diramphus and H. elegans. Five new forms are recorded, including one with 7-9 thoracic chaetigers. Three species are newly described: H. lambecki n. sp., H. similoides n. sp. and H. salazarvallejoi n. sp. Seven specific names are placed into synonymy: H. abbreviatus Krøyer [in] Mörch, H. benzoni Mörch, H. decorus Treadwell, H. dianthoides Augener, H. dunkeri Mörch, H. hexagonus Bosc and H. serratus Bush. A glossary, standard terminology and a key to all species from the Western Atlantic region are given.