Flabellina affinis is a species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea slug

Slug

Slug is a common name that is normally applied to any gastropod mollusc that lacks a shell, has a very reduced shell, or has a small internal shell...

, an aolid nudibranch

Nudibranch

A nudibranch is a member of what is now a taxonomic clade, and what was previously a suborder, of soft-bodied, marine gastropod mollusks which shed their shell after their larval stage. They are noted for their often extraordinary colors and striking forms...

, a marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusk in the family Flabellinidae

Flabellinidae

Flabellinidae is a taxonomic family of brightly-colored sea slugs, specifically nudibranchs, marine gastropod mollusks.This family has no subfamilies.-Genera and species:Genera and species within the family Flabellinidae include:...

.

Description

The species can grow to a length of 50 mm . It feeds primarily on the hydrozoa

Hydrozoa

Hydrozoa are a taxonomic class of very small, predatory animals which can be solitary or colonial and which mostly live in saltwater. A few genera within this class live in freshwater...

n Eudendrium, a very common hydroid in the Mediterranean Sea.

Distribution

This species is found in depths to 50 m in European waters along Portugal

Portugal

Portugal , officially the Portuguese Republic is a country situated in southwestern Europe on the Iberian Peninsula. Portugal is the westernmost country of Europe, and is bordered by the Atlantic Ocean to the West and South and by Spain to the North and East. The Atlantic archipelagos of the...

 and Spain

Spain

Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

, in the Mediterraneran Sea along Greece

Greece

Greece , officially the Hellenic Republic , and historically Hellas or the Republic of Greece in English, is a country in southeastern Europe....

, in the Atlantic Ocean from Portugal to Ghana

Ghana

Ghana , officially the Republic of Ghana, is a country located in West Africa. It is bordered by Côte d'Ivoire to the west, Burkina Faso to the north, Togo to the east, and the Gulf of Guinea to the south...

 and along the Canaries

Canaries

Canaries may refer to:* Canary Islands, an archipelago in the Atlantic belonging to Spain* Canaries Quarter, a village on the Caribbean island of Saint Lucia* "The Canaries", the nickname of two English football teams: Norwich City F.C. and Hitchin Town F.C....