Delphyodontos dacriformes was a prehistoric holocephalid

Chimaera

Chimaeras are cartilaginous fish in the order Chimaeriformes, known informally as ghost sharks, ratfish , spookfish , or rabbitfishes...

 fish from the early Carboniferous

Carboniferous

The Carboniferous is a geologic period and system that extends from the end of the Devonian Period, about 359.2 ± 2.5 Mya , to the beginning of the Permian Period, about 299.0 ± 0.8 Mya . The name is derived from the Latin word for coal, carbo. Carboniferous means "coal-bearing"...

, from the Bear Gulch Limestone

Bear Gulch Limestone

The Bear Gulch Limestone in Montana is a fossiliferous lagerstätte, a limestone layer laid down in the Mississippian epoch of the Carboniferous period, about 318 mya. This lens of limestone was laid down in a surrounding matrix that indicates a landscape of mudflats and braided channels in fresh...

 Lagerstätte

Lagerstätte

A Lagerstätte is a sedimentary deposit that exhibits extraordinary fossil richness or completeness.Palaeontologists distinguish two kinds....

, in Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

. Its fossils consist mainly of aborted fetuses or newly hatched young. Sharp teeth and fecal matter in the fossils suggests that Delphyodontos practiced intrauterine cannibalism

Intrauterine Cannibalism

Intrauterine Cannibalism is the first studio album by American brutal death metal band Malignancy.-Track listing:# "Rotten Seed" — 3:16# "Intrauterine Cannibalism" — 1:42# "Intestinal Sodomy" — 2:22# "Internal Corruption" — 1:48...

, like some modern sharks, such as gray reef shark

Gray reef shark

The grey reef shark is a species of requiem shark, family Carcharhinidae. One of the most common reef sharks in the Indo-Pacific, it is found as far east as Easter Island and as far west as South Africa. This species is most often seen in shallow water near the drop-offs of coral reefs...

s.

Appearance

According to the fossils, the recently born would have resembled tadpoles with small, but sharp beaks. Because of the evidence suggesting intrauterine cannibalism, D. dacriformes is assumed to have been carnivorous, though, besides siblings, it is unknown what other organisms they would have eaten.

Etymology

The generic name, Delphyodontos, means "womb tooth", in reference to the sharp, beak-like teeth and their possible habits of intrauterine cannibalism. The specific name, dacriformes, refers to the teardrop

Teardrop

Teardrop may refer to:* Tears, a liquid produced in the eyes for cleaning and lubricating* Teardrop attacks, a remote denial-of-service attack * Teardrop trailer, a type of travel trailer* Teardrop hull, a submarine hull design...

-shaped body.

External links

• http://www.sju.edu/research/bear_gulch/pages_fish_species/Delphyodontos_dacriformes.php