A NEW SPECIES OF UNIPORODRILUS (OLIGOCHAETA, TUBIFICIDAE) FROM THE GULF-OF-MEXICO COAST OF FLORIDA, AND A PHYLOGENETIC ANALYSIS OF THE GENUS

Uniporodrilus purus, new species, from subtidal sand near Pensacola in northwestern Florida, is described. It is distinguished from all cong eners by lacking penial setae. A most parsimonious cladistic hypothesi s of the species of Uniporodrilus (subfamily Phallodrilinae) is presen ted. It suggests a basal dichotomy of the genus, with U. purus and U. granulothecus, both subtidal species, constituting one clade character ized by unpaired male and spermathecal pores, and the four remaining s pecies, all intertidal, representing another clade characterized by a high number of somatic setae and enlarged pharyngeal cavity.