Chromosome complements from two populations of the marine wormNeanthes arenaceodentata(Annelida: Polychaeta)

The chromosome complements for two populations of the marine worm, Neanthes arenaceodentata are described. A diploid chromosome number of 18 was observed in a California population. A Connecticut population had a diploid number of 24. In addition to different chromosome numbers, the morphology of the chromosomes is different between the two populations. It is clear from the karyotypes that these populations represent different species. These results underscore the need for further taxonomic studies of the nereid polychaetes and suggest a role for cytogenetics in that process.