(Skarnsundet - The Trondheim fjord / 39 meters / 11.09.2002)

Phylum: Arthropoda

Class: Crustacea

Subclass: Malacostraca

Order: Isopoda

Suborder: Valvifera

Family: Arcturidae

Scientific name: Astacilla longicornis

 

Norwegian: pinnekreps

Distribution: This isopod is registered from Østfold and as far north as Lofoten. It lives on depths between 10 and 100 meters. If is often seen climbing in the Gorgonian fan (as in the pictures) where it filters water and catches food.

Characteristics: It is recognized by the very long antennas, and the long back segment. The legs are attached to the front and back segments. The females can reach a length of 3 cm, the males rarely exceed 1 cm. The segment plates are smooth, without any prickles, in contrast to the four other members of this family, found in Norwegian waters.

As can be seen on some of the pictures below, this isopod takes good care of the little ones. Newly hatched babies are sometimes observed on their mother's antennae.

All pictures: