SAITHE

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 color with a dark back while P. virens is bright silver with a very dark greenback. P. virens generally appears to have relatively smaller eyes. The lateral line of P. pollachiushas a noticeable kink over the pectoral fins while that of P. virens is straighter.
The flesh of coalfish (P. virens) is darkly colored (hence the common name) while that of P. pollachius is similar to other members of the cod family.