Morphological abnormalities in Corycaeus speciosus Dana, 1849 (Copepoda, Cyclopoida) from the area of an Equatorial Atlantic Island

Abstract

Taxonomic and ecological studies of a large number of specimens can lead to the finding of morphological anomalies. Thus, based on 800 specimens of Corycaeus speciosus in different developmental stages (juvenile and adult copepodites) this study was carried out to assess for the first time anomalies in Equatorial Atlantic specimens. Samples were collected around the St. Peter and St. Paul Archipelago (Equatorial Atlantic). Anomalies were found at the end of the prosome in two female specimens, one recorded in the juvenile copepodite stage V and was characterized by a left-side rounded prosome tip, while in the adult the anomaly was characterized by a rounded prosome inner the tip in the left-side. The causes of the malformations remain unknown, but the results are indicative that they are probably genetic in character, transmitted on reproduction. However, experimental tests are necessary to confirm such conclusions and their effect on the population structure of this ecologically important species.