Belongs within: Cyclostomata. The Petromyzontidae, lampreys, are eel-like vertebrates with a filter-feeding freshwater larval stage that develops into non-feeding or parasitic, often marine, adults (Bond 1996). Characters (from Bond 1996): Body eel-like, dorsal and caudal fins present, lacking paired fins or scales; eyes lateral; mouth ventral, consisting of a circular disc set with horny teeth;… Continue reading Petromyzontidae


Belongs within: Craniata.Contains: Myxinidae, Petromyzontidae. Tully as a vertebrate Published 17 March 2016 Several years ago, I included the ‘Tully monster’ Tullimonstrum gregarium in a list of some of the most phylogenetically mysterious organisms on the planet. Multiple suggestions have been made as to its affinities: mollusc, annelid, nemertean (nemerteans and sea cuumbers both having… Continue reading Cyclostomata