Ptolemaiida
Encyclopedia
Ptolemaiida is a taxon of wolf-sized mammals presumed to be descended from pantolestid
cimolestids
that lived in Northern and Eastern Africa
during the Paleogene
. The oldest fossils are from the latest Eocene
strata of the Jebel Qatrani Formation
, near the Fayum oasis in Egypt
.
Some experts place Ptolemaiida, incertae sedis
, in Afrotheria
, on the basis of paleobiology
, as the taxon was endemic to Paleocene Africa, and because of some similarities in skull anatomical features in common with those in aardvark
s.
There have been much confusion about the origins and even identities of the ptolemaiids. The first specimen, a set of isolated molar teeth, of the type species
, Ptolemaia lyonsi, was originally identified as being a primate, as they were flat and nearly identical to those of primates. Later, when the first skull was found, it was then thought to be a monstrous, wolf-sized shrew, as the skull had long canine fangs, and was very gracile. However, recently, there has been reconsideration of the ptolemaiids' diet, and possible behavior, as wear on the teeth suggest it crushed hard or abrasive food, and that the teeth had little or no shearing ability. Even so, some sources still refer to them as being gigantic, carnivorous shrews.
Pantolestidae
Pantolestidae is an extinct family of semi-aquatic, placental mammals that took part in the first placental evolutionary radiation together with other early mammals such as the leptictids....
cimolestids
Cimolesta
Cimolesta is an extinct order of mammals. A few experts place the pangolins within Cimolesta, though most other experts prefer to place the pangolins within their own order, Pholidota....
that lived in Northern and Eastern Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
during the Paleogene
Paleogene
The Paleogene is a geologic period and system that began 65.5 ± 0.3 and ended 23.03 ± 0.05 million years ago and comprises the first part of the Cenozoic Era...
. The oldest fossils are from the latest Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
strata of the Jebel Qatrani Formation
Jebel Qatrani Formation
The Jebel Qatrani Formation is a palaeontological formation located in Egypt. It dates to the Eocene-Oligocene period....
, near the Fayum oasis in Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
.
Some experts place Ptolemaiida, incertae sedis
Incertae sedis
, is a term used to define a taxonomic group where its broader relationships are unknown or undefined. Uncertainty at specific taxonomic levels is attributed by , , and similar terms.-Examples:*The fossil plant Paradinandra suecica could not be assigned to any...
, in Afrotheria
Afrotheria
Afrotheria is a clade of mammals, the living members of which belong to groups from Africa or of African origin: golden moles, sengis , tenrecs, aardvarks, hyraxes, elephants and sea cows. The common ancestry of these animals was not recognized until the late 1990s...
, on the basis of paleobiology
Paleobiology
Paleobiology is a growing and comparatively new discipline which combines the methods and findings of the natural science biology with the methods and findings of the earth science paleontology...
, as the taxon was endemic to Paleocene Africa, and because of some similarities in skull anatomical features in common with those in aardvark
Aardvark
The aardvark is a medium-sized, burrowing, nocturnal mammal native to Africa...
s.
There have been much confusion about the origins and even identities of the ptolemaiids. The first specimen, a set of isolated molar teeth, of the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
, Ptolemaia lyonsi, was originally identified as being a primate, as they were flat and nearly identical to those of primates. Later, when the first skull was found, it was then thought to be a monstrous, wolf-sized shrew, as the skull had long canine fangs, and was very gracile. However, recently, there has been reconsideration of the ptolemaiids' diet, and possible behavior, as wear on the teeth suggest it crushed hard or abrasive food, and that the teeth had little or no shearing ability. Even so, some sources still refer to them as being gigantic, carnivorous shrews.