Integumental Structures in the Oral Field of Eurytemora Affinis and Acartia Tonsa (Copepoda, Calanoida) in Relation To Their Trophic Habits

Abstract

[Scanning electron microscopy (SEM) was used to study the morphology of the integumental structures in the oral field of the copepods Eurytemora affinis and Acartia tonsa. Structures observed in these two copepods were different in type, number, and location. E. affinis presented only structures of a filiform type, distributed all over the oral field, whereas in A. tonsa three different types of structures were observed: filiform, papilliform, and conical, distributed according to a complex pattern. The results obtained on the chaetotaxy of the oral field demonstrate a strong morphological adaptation of each copepod to its trophic habits. The ecological implications of these results on the coexistence of populations of both species in the Bahia Blanca estuary are discussed., Scanning electron microscopy (SEM) was used to study the morphology of the integumental structures in the oral field of the copepods Eurytemora affinis and Acartia tonsa. Structures observed in these two copepods were different in type, number, and location. E. affinis presented only structures of a filiform type, distributed all over the oral field, whereas in A. tonsa three different types of structures were observed: filiform, papilliform, and conical, distributed according to a complex pattern. The results obtained on the chaetotaxy of the oral field demonstrate a strong morphological adaptation of each copepod to its trophic habits. The ecological implications of these results on the coexistence of populations of both species in the Bahia Blanca estuary are discussed.]