Pollachius virens

Saithe (/seɪð/ or /seɪθ/),Pollachius virens, is a species of marine fish in the Pollachius genus. Together with Pollachius pollachius it is generally referred to in the U.S. as pollock. Other names include the Boston blues (separate from bluefish), coalfish/coley and saithe in the UK.

Description

This species can be separated from P. pollachius by looking at the relative lengths of the upper and lower jaws. P. pollachius has a longer underslung lower jaw while P. virens has approximately equal upper and lower jaw lengths. This gives a very different profile to the head. In general P. pollachius is a brown or golden colour with a dark back while P. virens is bright silver with a very dark green back. P. virens generally appears to have relatively larger eyes. The lateral line of P. pollachius has a noticeable kink over the pectoral fins while that of P. virens is straighter.

The flesh of coalfish (P. virens) is darkly coloured (hence the common name) while that of P. pollachius is similar to other members of the cod family. This dark colour in the fresh uncooked flesh may have led to the undeserved reputation of this fish as poor for eating.