Zeus faber

The John dory or Zeus faber is a species belonging to the order Zeiformes, within which it belongs to the Zeidae family. It is a common species in the waters of the Mediterranean Sea, the Black Sea, the eastern Atlantic Ocean from Norway and the Faroe Islands to South Africa, and in the Indo-West Pacific region from South Africa to Kenya, Australia, New Zealand and Japan. Generally, specimens of this species are found near the bottom or in intermediate waters, from the coast to at least 400 m, but it is more common between 20 and 160 m depth.

With an oval body and strongly compressed laterally, Zeus faber can grow to a maximum total length of 65 cm and weights up to 5 kg. It has a relatively large, slightly pointed rostrum, with a highly extensible terminal mouth that is positioned obliquely superiorly on the underside. The dorsal profile of the head is straight or slightly convex, and the large eyes in an upper lateral position are prominent on the face. At the posterior end of the lower jaw there are two spines.

The dorsal fin of Zeus faber has a first region formed by 9-11 spines, followed almost without space by a second region formed by 21-25 soft rays. The rays of the spiny region of the dorsal fin have membranous filaments that can be as long as the length of the spines themselves. The anal fin consists of a first region with 3-5 spines followed closely by a second anal fin with 20-24 soft rays in the posterior third of the body. It should be noted that the first three spines of the dorsal fin, as well as the first two of the anal fin have a mechanism by which they can be locked at the will of the specimen. The high pelvic fins, which are located at the vertical height of the posterior edge of the eyes, are formed by a spine and between 6 or 7 soft rays. There are also 5 to 10 bony structures on the body containing large backward-facing spines, which are located along each side of the base of the dorsal fin, with the first of these structures located at the level of the last spine of the dorsal fin. The spines of these bony structures gradually increase in size as we move toward the rear of the specimen. Similarly, another 6-11 similar structures occur on each side of the base of the anal fin, each with two spines.

The body color of Zeus faber is golden-greenish gray, with a central black ocellus bordered by a narrow grayish or yellowish line. The fins have dark colored membranes, both in the spiny region of the dorsal, anal and pelvic fins.

The diet of Zeus faber is based on a wide variety of small fish species, cephalopods and crustaceans that it catches solitarily during the day. In general, this is not a fish species that we can consider as a great swimmer, and it moves relatively slowly. What it is extremely fast is the opening movement of the mouth, with which it sucks in prey that comes within its reach.