''Crocodylus anthropophagus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

crocodile Crocodiles (family (biology), family Crocodylidae) or true crocodiles are large semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term crocodile is sometimes used even more loosely to inclu ...

from the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

Tanzania Tanzania (; ), officially the United Republic of Tanzania ( sw, Jamhuri ya Muungano wa Tanzania), is a country in East Africa within the African Great Lakes region. It borders Uganda to the north; Kenya to the northeast; Comoro Islands and ...

. It lived 1.84 million years ago. It was a large-sized

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

reaching a length of .

Etymology

''Crocodylus anthropophagus'' was first named by Christopher A. Brochu, Jackson Njau, Robert J. Blumenschine and Llewellyn D. Densmore in

2010 File:2010 Events Collage New.png, From top left, clockwise: The 2010 Chile earthquake was one of the strongest recorded in history; The Eruption of Eyjafjallajökull in Iceland disrupts air travel in Europe; A scene from the opening ceremony of ...

. The specific name ''anthropophagus'' is from Greek word "''anthropos''" that means "human" and Greek word "'" that means "eater", in reference to the evidence that this animal included hominids in its diet.

Taxonomy

The

holotype specimen A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

, NNHM-1001, comprises a skull and partial skeleton. All specimens were discovered in

Olduvai Gorge The Olduvai Gorge or Oldupai Gorge in Tanzania is one of the most important paleoanthropology, paleoanthropological localities in the world; the many sites exposed by the gorge have proven invaluable in furthering understanding of early human ev ...

, Tanzania, in two different rock formations dating to 1.845 and 1.839 million years ago in the

Plio-Pleistocene The Plio-Pleistocene is an informally described geological pseudo-period, which begins about 5 million years ago (Mya) and, drawing forward, combines the time ranges of the formally defined Pliocene and Pleistocene epochs—marking from about 5&nbs ...

. The

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

below is from a 2021 study based on the finding of a new ''C. anthropophagus'' partial

cranium The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

Description

The skeleton is consistent with living representatives of the genus. The

axis An axis (plural ''axes'') is an imaginary line around which an object rotates or is symmetrical. Axis may also refer to: Mathematics * Axis of rotation: see rotation around a fixed axis * Axis (mathematics), a designator for a Cartesian-coordinat ...

vertebra has a projection on the underside (a hypapophysis) which seems to have largely fused to the vertebra itself. The vertebrae are procoelous in shape, with a spherical projection extending from the back side which attaches to a concave socket on the front end of the preceding vertebra. The

femora The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with t ...

slightly bend in an S-shape. However, ''C. anthropophagus'' lacks the shallow bony pair of crests running from the eyes to the nose like in Indopacific ''Crocodylus'', and lacks a boss (a lump of bone) on the middle of the snout like in Neotropical ''Crocodylus''. The right

premaxilla The premaxilla (or praemaxilla) is one of a pair of small cranial bones at the very tip of the upper jaw of many animals, usually, but not always, bearing teeth. In humans, they are fused with the maxilla. The "premaxilla" of therian mammal has b ...

(the bone that makes up the front end of the snout) of the holotype preserved three

tooth sockets Dental alveoli (singular ''alveolus'') are sockets in the jaws in which the roots of teeth are held in the alveolar process with the periodontal ligament. The lay term for dental alveoli is tooth sockets. A joint that connects the roots of the ...

, with a notable gap in between the first and second sockets. Another specimen's left

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

(the bone that makes up the back end of the snout) preserved 13 circular sockets, though it may have partially preserved a 14th. There was a gap between the 9th and 10th. The teeth were all conical and lacked serrations. It had two prominent, triangular “horns” over the ears.

Paleoecology

''Crocodylus anthropophagus'' was the largest predator encountered by human ancestors at

, as indicated by

hominin The Hominini form a taxonomic tribe of the subfamily Homininae ("hominines"). Hominini includes the extant genera ''Homo'' (humans) and '' Pan'' (chimpanzees and bonobos) and in standard usage excludes the genus ''Gorilla'' (gorillas). The t ...

specimens preserving crocodile bite marks from these sites. Its type locality is near those for ''

Homo habilis ''Homo habilis'' ("handy man") is an extinct species of archaic human from the Early Pleistocene of East and South Africa about 2.31 million years ago to 1.65 million years ago (mya). Upon species description in 1964, ''H. habilis'' was highly ...

'' and ''

Paranthropus boisei ''Paranthropus boisei'' is a species of australopithecine from the Early Pleistocene of East Africa about 2.5 to 1.15 million years ago. The holotype specimen, OH 5, was discovered by palaeoanthropologist Mary Leakey in 1959, and described by h ...

''.

References

This article incorporates CC-BY-2.5 text from the reference.

External links

Ancient Human Ancestors Faced Fearsome Horned Crocodile
LiveScience {{Taxonbar, from=Q1932167 Crocodylidae Reptiles described in 2010 Fossil taxa described in 2010 Pleistocene crocodylomorphs Pliocene crocodylomorphs Pleistocene reptiles of Africa Pliocene reptiles