Zaphlegidae
Encyclopedia
Euzaphlegidae is a family of extinct, snake mackerel
-like, or escolar
-like fish whose fossils are found from Late Miocene
strata of Southern California
.
s or wahoo
, leading some researchers to place them within Scombridae
or Cybiidae, respectively. However, x-ray analysis of the bone structure strongly suggests a relationship with the snake-mackerels, with some experts placing them within Gempylidae.
, and herring, Xyne grex, found within the stomachs of several specimens of Thyrsocles
and Euzaphleges. Researcher Lore Rose David proposed that, because the Euzaphlegidae were comparatively less adapted to a pelagic lifestyle like the gempylids, but had slender skeletons suggesting of a deep-water lifestyle, the Euzaphlegidae lived in deep, offshore communities near the ocean floor, where they preyed on other fish. David also suggested that the Euzaphlegidae presence in Miocene California excluded the gempylids from establishing themselves at the time, while the presence of scombrids in shallower water ecosystems prevented the Euzaphlegidae from establishing themselves in shallow water.
During the time of the Late Miocene, Southern California had a very warm, tropical climate. The transition from Late Miocene to Early Pliocene
saw the climate cool, and this cooling event drove the Euzaphlegidae and several other (locally) endemic fish species, such as the manefish
Chalcidichthys
and the spinyfin
Absalomichthys
, into extinction. This cooling event, coupled with the survival of the scombrids in southern Californian marine ecosystems, also helped prevent gempylids from replacing the Euzaphlegidae during the Pliocene or Pleistocene
.
Snake mackerel
Gempylidae is a family of perciform fishes, commonly known as snake mackerels or escolars.They are elongate fishes with a similar appearance to barracudas, having a long dorsal fin, usually with one or finlets trailing it. The largest species, including the snoek, Thyrsites atun, grow up to two...
-like, or escolar
Escolar
The escolar, Lepidocybium flavobrunneum, a species of fish in the family Gempylidae, is found in deep tropical and temperate waters around the world...
-like fish whose fossils are found from Late Miocene
Miocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
strata of Southern California
Southern California
Southern California is a megaregion, or megapolitan area, in the southern area of the U.S. state of California. Large urban areas include Greater Los Angeles and Greater San Diego. The urban area stretches along the coast from Ventura through the Southland and Inland Empire to San Diego...
.
Description and Taxonomy
In life, the Euzaphlegidae would have born a superficial resemblance to mackerelMackerel
Mackerel is a common name applied to a number of different species of fish, mostly, but not exclusively, from the family Scombridae. They may be found in all tropical and temperate seas. Most live offshore in the oceanic environment but a few, like the Spanish mackerel , enter bays and can be...
s or wahoo
Wahoo
The wahoo is a scombrid fish found worldwide in tropical and subtropical seas. It is best known to sports fishermen, as its speed and high-quality flesh make it a prize game fish...
, leading some researchers to place them within Scombridae
Scombridae
Scombridae is the family of the mackerels, tunas, and bonitos, and thus includes many of the most important and familiar food fishes. The family consists of about 55 species in 15 genera and two subfamilies...
or Cybiidae, respectively. However, x-ray analysis of the bone structure strongly suggests a relationship with the snake-mackerels, with some experts placing them within Gempylidae.
Ecology and Evolution
The sharp teeth and mackerel-like forms strongly suggest that the zaphlegids were predators, verified by the remains of numerous extinct deep sea smelt, BathylagusBathylagus
Bathylagus is a genus of ray-finned fish in the Bathylagidae family.-Species:* Bathylagus andriashevi Kobyliansky, 1986.* Bathylagus antarcticus Günther, 1878.* Bathylagus borealis Gilbert, 1896....
, and herring, Xyne grex, found within the stomachs of several specimens of Thyrsocles
Thyrsocles
Thyrsocles is an extinct genus of prehistoric bony fish that lived during the Upper Miocene subepoch.-See also:* Prehistoric fish* List of prehistoric bony fish...
and Euzaphleges. Researcher Lore Rose David proposed that, because the Euzaphlegidae were comparatively less adapted to a pelagic lifestyle like the gempylids, but had slender skeletons suggesting of a deep-water lifestyle, the Euzaphlegidae lived in deep, offshore communities near the ocean floor, where they preyed on other fish. David also suggested that the Euzaphlegidae presence in Miocene California excluded the gempylids from establishing themselves at the time, while the presence of scombrids in shallower water ecosystems prevented the Euzaphlegidae from establishing themselves in shallow water.
During the time of the Late Miocene, Southern California had a very warm, tropical climate. The transition from Late Miocene to Early Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
saw the climate cool, and this cooling event drove the Euzaphlegidae and several other (locally) endemic fish species, such as the manefish
Manefish
Manefishes are perciform fishes in the family Caristiidae. They are deep-sea marine fishes that eat siphonophores.-Genera and species:* Genus Caristius** Caristius groenlandicus Jensen, 1941.** Caristius japonicus Gill & Smith, 1905....
Chalcidichthys
Chalcidichthys
Chalcidichthys malacapterygius is an extinct, prehistoric manefish that lived during the Upper Miocene subepoch of Southern California. It is assumed to have preyed on siphonophores, like its living relatives.-See also:* Prehistoric fish...
and the spinyfin
Spinyfin
Spinyfins are a family, Diretmidae, of beryciform fishes. The name is from Greek, di meaning "two" and eretmos meaning "oar". They are found worldwide in deep waters, down to as much as ....
Absalomichthys
Absalomichthys
Absalomichthys velifer is an extinct, prehistoric spinyfin that lived during the Upper Miocene of what is now Southern California. Its dorsal fin was huge in comparison with living species.-See also:* Prehistoric fish* List of prehistoric bony fish...
, into extinction. This cooling event, coupled with the survival of the scombrids in southern Californian marine ecosystems, also helped prevent gempylids from replacing the Euzaphlegidae during the Pliocene or Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
.