Fig. 198.—Skull of a Berycoid fish, Beryx splendens Cuv. & Val., showing the orbitosphenoid (OS), characteristic of all Berycoid fishes.
These fishes, most primitive of the thoracic types, were more abundant in Cretaceous and Eocene times than now. The possession of an increased number of soft rays in the ventral fins is archaic, although in one family, the Monocentridæ, the number is reduced to three. Most of the living Berycoidei retain through life the archaic duct to the air-bladder characteristic of most abdominal or soft-rayed fishes. In some however, the duct is lost. For the first time in the fish series the number of twenty-four vertebræ appears. In most spiny-rayed fishes of the tropics, of whatever family, this number is retained.
In every case spines are present in the dorsal fin, and in certain cases the development of the spinous dorsal surpasses that of the most extreme perch-like forms. In geological times the Berycoids preceded all other perch-like fishes. They are probably ancestral to all the latter. All the recent species, in spite of high specialization, retain some archaic characters.
The Alfonsinos: Berycidæ.—The typical family, Berycidæ, is composed of fishes of rather deep water, bright scarlet or black in color, with the body short and compressed, the scales varying in the different genera. The single dorsal fin has a few spines in front, and there are no barbels. The suborbitals are not greatly developed.
Fig. 199.—Beryx splendens Lowe. Gulf Stream.
The species of Beryx, called in Spanish Alfonsino, Beryx elegans and Beryx decadactylus, are widely distributed at moderate depths, the same species being recorded from Portugal, Madeira, Cuba, the Gulf Stream, and Japan. The colors are very handsome, being scarlet with streaks of white or golden. These fishes reach the length of a foot or more and are valued as food where sufficiently common.
Numerous species of Beryx and closely allied genera are found in all rocks since Cretaceous times; Beryx dalmaticus, from the Cretaceous of Dalmatia, is perhaps the earliest. Beryx insculptus is found in New Jersey, but no other Berycoids are yet known as fossils from North America. Sphenocephalus, with four anal spines, is found in the chalk, as are also species of Acrogaster and Pycnosterinx, these being the earliest of fishes with distinctly spiny fins.
Fig. 200.—Hoplopteryx lewesiensis (Mantell), restored. English Cretaceous Family Berycidæ. (After Woodward.)