Family Moronidae

Temperate basses

The family comprises two genera, Morone, with four species in North America and Dicentrarchus, with two species in the Eastern Atlantic, Black Sea, and Mediterranean. They are distinguished by having two narrowly separated dorsals, two opercular spines, a lateral line extending almost to the posterior margin of the caudal, and auxiliary rows of lateral-line scales on the caudal above and below the main row. The two Dicentrarchus species enter brackish waters. Dicentrarchus labrax is the only species of the genus known to inhabit freshwater habitats. In contrast, D. punctatus is known to enter brackish waters only occasionally on the Atlantic coasts of France, the Iberian Peninsula, and the Mediterranean, and the western Black Sea. Hybrids between female Morone saxatilis and male M. chrysops are increasingly used in aquaculture in Israel and several European countries. There are many records of individuals who have escaped from captivity. Hybrids are fertile but produce only a few offspring. As aquaculture of these fishes expands, the number of records will increase, potentially leading to the establishment of local populations. This voracious predator exerts strong effects on fish communities. Morone hybrids can be distinguished from Dicentrarchus species by having small serrations along the lower part of the preoperculum, directed downward (vs. forward) and 5–7 lateral stripes (vs. body plain or spotted). Dicentrarchus can be distinguished from superficially similar Sander species and (introduced) Micropterus by the presence of spines on the lower part of the preoperculum (vs. preoperculum smooth), the presence of auxiliary rows of lateral-line scales on the caudal (vs. absence), the concave posterior margin of the anal (vs. convex in Micropterus), and the presence of three anal spines (vs. two in Sander).

Further reading. Johnson, in Moser et al. 1984 (phylogeny); Pickett & Pawson 1994 (biology); Müller-Belecke & Zienert 2006 (Morone aquaculture).