Fish Identification Photos: Yellowfin Herring, Pliosteostoma lutipinnis: The Yellowfin Herring has a deep body that is narrow and flexible, giving it an awkward gangly appearance. It has an olive back with silver-white sides and yellow fins. Characteristically, the Yellowfin Herring's dorsal fin originates behind the origin of the anal fin, there are no pelvic fins, the upper head profile is concave, and the mouth turned upward with a strongly projecting lower jaw.

The Yellowfin Herring can be easily confused with the Pacific Longfin Herring, Opisthopterus dovii (anal fin originates closer to the tail than the snout; dorsal fin originates closer to the caudal fin than the pectoral fins; dark line along the back) and possibly the Pacific Ilisha or Hachet Herring, Ilisha furthii (dorsal fin originates before the origin on the anal fin; small pelvic fins) and the Tropical Longfin Herring, Neoopisthopterus tropicus (very long anal fin base, small pointed dorsal fin, silver stripe along the flank).

The Yellowfin Herring reaches a length of 10 inches and is virtually weightless. It is normally found in the first 30 feet of the water column in small schools over sandy bottoms.

The Yellowfin Herring is a member of the Clupeidae or Herring Family. In general, they are modest-sized, silvery, shallow water fishes that have elongated compressed bodies. They are characterized by scuted keels along the belly, a single dorsal fin that originates behind the middle of the body, anal fins with a very long base that commence before the origin of the dorsal fin, no pelvic fins, no lateral lines, and mouths with short large jaws that point obliquely up with a projecting lower jaw.

The genus Pliosteostoma has one member, the Yellowfin Herring. Globally, 34 species of Pristigasteridae have been identified, of which 8 are found in the tropical Eastern Pacific.

The Yellowfin Herring is a coastal pelagic species that is reported to be found in Mexican waters only in the very southern portion of the Sea of Cortez and along the coast of the mainland south to Guatemala. It appears to be absent from all oceanic islands.

Yellowfin Herring, Pliosteostoma lutipinnis: Shows up when one purchases a “scoop of bait.” Caught in the surf zone, La Playita, San Jose del Cabo, Baja California Sur, Mexico, during the winter months with water temperatures below 78 degrees, early morning in 5 to 10 foot deep water utilizing a cast net by panguero bait salesmen. Adult size approximately 10 inches and a very awkward strange fish that is virtually weightless. Used on a limited basis as a live bait for Sierra but otherwise viewed by locals to be of limited value. Can be used as cut bait. Does not survive a panga “bait tank” except at a modest level. The photo sequence above shows the maturation of the species starting from an almost transparent state. Description and photo courtesy John Snow.