The objective is to describe the population structure of Comesoma arenae Gerlach, 1956 during a one-year period. The area studied, Coroa Grande, is located in Sepetiba Bay, State of Rio de Janeiro, Brazil. Sampling was carried out monthly, from May 1998 through April 1999. Most individuals in the population were adults, of which non-ovigerous females were the most abundant. The species showed its highest population densities during the colder months.
Marine nematodes; meiofauna
