Foraminiferan (Protozoa) epizoites on the anthuridean (Crustacea, Isopoda) Calathura brachiata (Stimpson)

Abstract

Foraminiferan epizoites were studied on the isopod Calathura brachiata ( Stimpson). Most individuals found belonged to the genus Cibicides. The foraminiferans were either rare or quite frequent on Calathura brachiata, indicating patchy occurrence of living foraminiferans. They were most frequent on the anterior part of the body ( head, ® rst pereonites) and the ® rst two pairs of legs ( pereopods). This pattern, which is unusual among foraminiferan epizoites on isopods, is explained by habitat selection of the foraminiferans and the behaviour of the isopod, which presumably rests between feeding with the anterior part of the body held in an upward position, allowing foraminiferans to settle on mouthparts and on the legs (® rst two pereopods) used in grasping prey. The size range of the foraminiferans indicates that settling of foraminiferans from the water column is more important for the development of foraminiferan epibiosis on Calathura than migration of individuals from the bottom and this may be the general pattern for most isopod species.

First fossil evidence of a drill hole attributed to an octopod in a barnacle

“…To our knowledge, little has been published about the encrusting behaviour of this foraminifer from the pre‐Holocene Cenozoic fossil record unlike for modern environments (e.g. Svavarsson & Ólafsdóttir ; Richardson‐White & Walker ). Our research thus expands the knowledge of this behaviour and also reports on the additional evidence of encrustation of drill holes.…”