Family Hexagrammidae 316greenlings Marine North Pacific

Head with cirri but without ridges or spines; lateral lines one or five; scales cycloid or ctenoid; one dorsal fin (but with a notch) with 16-28 spines and 11-30 soft rays; pelvic fin with one spine and five soft rays; well-developed anterior nostril on each side, posterior nostril (if present) reduced to a small

pore; anal fin with 0-3 spines followed by soft rays; six or seven branchioste-gal rays; swim bladder absent; vertebrae 36-63. Maximum length up to 1.5 m, attained in Ophiodon elongatus; most other species less than 45 cm.

Although small, this is the most speciose family endemic to the North Pacific. Most species are primarily littoral.

Five subfamilies, five genera, and 12 species (Mecklenburg and Eschmeyer, 2003). Nelson (1994) gave references for the basis of this classification. Shinohara (1994) should be consulted for its study of comparative morphology and phylogeny.

Subfamily Hexagramminae (Greenlings). Dorsal fin divided approximately in the middle by a notch into an anterior spinous portion and a posterior soft portion; anal fin without spines; head covered with scales; caudal fin rounded, truncate, or slightly emarginate; no large ridges on skull; single lateral line (in the one species of the subgenus Agrammus, H. agrammus of Japan, Korea, and North China) or five (some may be short); vertebrae 47-57.

One genus, Hexagrammos, with six species, from western and eastern coasts of the North Pacific (south to Japan and northern Mexico).

Subfamily Pleurogramminae. Dorsal fin without a notch but with 21-24 spines and 24-30 soft rays; anal fin usually without a spine and with 23-32 soft rays; scales partly covering head; caudal fin forked; strongly developed ridges on upper surface of skull; five lateral lines on body; vertebrae 59-62. Primarily pelagic.

Two species of Pleurogrammus (Atka mackerels) in the northern Pacific from northern Japan to Alaska (rarely south to California).

Subfamily Ophiodontinae. Dorsal fin divided into two parts by a deep notch, first portion with 24-28 spines and second portion with 20-24 soft rays; anal fin with three nonsegmented rays and 21-25 soft rays; head not covered with scales; only member with cycloid scales on body, others may have cycloid scales on head; caudal fin truncate or slightly emarginate; single lateral line; mouth large; jaws with small teeth interspersed with large fanglike teeth; feeds primarily on fishes, crustaceans, and squids and is extremely voracious; 57-59 vertebrae.

One species, Ophiodon elongatus (Lingcod), of eastern Pacific from southern Alaska to northern Mexico.

Hexagrammidae

Subfamily Oxylebiinae. Dorsal fin divided by a shallow notch; anal fin usually with three large spines, of which the second is longest; scales covering the head; caudal fin rounded; one lateral line.

One species, Oxylebius pictus (painted greenlings), of eastern Pacific from British Columbia to California.

Subfamily Zaniolepidinae (combfishes). Dorsal fin with deep notch in posterior third of fin; first three dorsal fin spines elongate, the second greatly prolonged in Zaniolepis latipinnis; ctenoid scales; first two pelvic fin rays thickened and extending past origin of anal fin; one lateral line. Primarily benthic. Maximum length about 30 cm.

Hexagrammidae

Two species, Zaniolepis frenata and Z. latipinnis, found in eastern North Pacific from British Columbia to California.

Suborder Normanichthyoidei. The relationships of the one included species, described by H. W. Clark in 1937, are very uncertain. It was previously excluded from the Cottoidei, and this is supported by recent work (e.g., Yabe and Uyeno, 1996; Smith and Wheeler, 2004); but its relationships remain uncertain. Further comments are given in Nelson (1994).

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