Facelina bostoniensis (Boston facelina)

Identification

The body is translucent white, with a rose coloured hue around the mouth. The red oesophagus, situated just behind the rhinophores, is clearly visible. There are a few patches of white pigment on the head, between the rhinophores and down the tail of the animal. Sometimes blue iridescence is present in small areas around the head, but is missing on the cerata. The rhinophores are annulate, the oral tentacles are very long, both sets of tentacles are tipped with white pigment. The brown digestive gland is visible through the cerata epidermis.

Status

Unassessed by the IUCN Red list, but frequently seen in Europe.

Habitat

It can be found on both sides of the Atlantic Ocean, in the US, Canada, parts of the North Sea, in the Netherlands, Germany, and the Eastern Mediterranean. They are usually found on hard substrates, on or nearby hyrdroids, in a depth range of 2-37 meters.

Reproduction

Nudibranchia are simultaneous hermaphrodites, meaning they are male and female simultaneously. They lay eggs which are deposited on a substratum where they develop and hatch into a larval stage and grow further as adults.

Size

Up to 5,5cm.

Prey / Predation

They feed on hydroids, most commonly Tubularia species.

Special features

The name was derived from the first descriptions of this species in Massachusetts, America. Only a few years later the first descrptions from the other side of the Atlantic, Europe, came in. It closely resembles Facelina auriculata, but F. bostoniensis is more bulky, and the rhinophores are white in stead of yellow.