Larval development of Elminius covertus Foster and Hexaminius popeiana Foster (Cirripedia : Archaeobalanidae : Elminiinae) reared in the laboratory

Abstract

The presence of embryos in the mantle cavity of E. covertus and H. popeiana has been monitored over a 2-year period. E. covertus has a clearly defined seasonal pattern with peak breeding during the winter and early spring. H. popeiana shows high levels of breeding activity throughout the year.

The larval stages of E. covertus and H. popeiana are described from larvae reared in the laboratory. Morphological differences in each larval stage allow the larvae of the two species to be distinguished without difficulty. Differences between the larval stages of E. covertus and E. modestus are more minor, but are sufficient to distinguish most stages. Similarities in the larval morphology of the genera Elminius and Hexaminius support their inclusion in the subfamily Elminiinae. The larvae of H. popeiana also share features with the larvae of archaeobalanines, especially Conopea galeata.