Sertularia vervoorti (Hydrozoa: Sertulariidae), an undescribed species of hydroid from Brazil

An account is given of Sertularia vervoorti spec. nov., a small leptothecate species collected in coastal waters of southeastern Brazil. Specimens were found on brown algae, collected at depths of 15-20 m on the inner continental shelf off Espírito Santo state. This hydroid resembles Sertularia tumida Allman, 1877, S. linealis Warren, 1908, and S. longa Millard, 1958, but differs from these and other species of the genus in having an unusual bulge around the hydrothecal wall just distal to its insertion with the hydrocaulus. The colony form of S. vervoorti is more compact than in these species, and gonothecae are annulated rather than smooth as in S. linealis and S. longa.