Spot (fish)

Species of fish

The spot (Leiostomus xanthurus), also known commonly as the spot croaker, Lacépède named this new species in a new monospecific genus, Leiostomus. This genus has been placed in the subfamily Sciaeninae by some workers, but the 5th edition of Fishes of the World does not recognise subfamilies within the Sciaenidae which it places in the order Acanthuriformes.

The spot's generic name, Leiostomus means "smooth mouth" and refers to the toothless lower jaw. The specific name xanthurus means "yellow tail" and is a misnomer as the tail is not yellow, but it may have been coinfused for Bairdiella chrysoura.

The spot is relatively deep bodied and compressed with a humped back. The mouth is almost horizontal and is equipped with bands of small teeth. There is no barbel on the chin but there are five pores there with more pores on the snout, five on the sides and five at the front. The upper angle of the operculum is incised and the edge of the preoperculum is smooth and not serrated. The dorsal fin is deeply incised, the incision separating the front, spiny part of the fin with 11 spines and the rear soft rayed part which is supported by 29 to 35 soft rays. The anal fin contains two spines and 12 or 13 soft rays, the second spine being half the length of the first soft ray. The caudal fin is truncate, sometimes slightly notched. They have large ctenoid scales, except for those beneath the eye and on the lower head which are cycloid. A scale row, or two, runs along the base of the soft rayed part of the dorsal fin. This species reaches a maximum total length of , although is more typical. The color of the body is bluish gray on the upper body becoming yellow or golden on the lower body. In young fishes there is a series of dark bars run diagonally from the back to the middle of the flanks, these fade as the fish ages. There is a large black spot on the body above the upper margin of the operculum.

The spot spawns in fall to early winter time. It moves from its typical bay and estuary habitat to an offshore area of deeper water, where up to 1.7 million eggs may be laid. The eggs are externally fertilized and pushed back toward shore. Larvae quickly grow in the warmer offshore water and move into coastal shallows and bays for winter.