Palaeomerycidae
Encyclopedia
Palaeomerycidae is an extinct family
of ruminants (thus being even-toed ungulate
s of order
Artiodactyla), probably ancestral to deer
and musk deer
. They lived in North America
, Europe
, Africa
, and Asia
from the Eocene
to Miocene
epoch 55.8 to 5.3 Ma, existing for approximately .
The oldest specimens are of Amphitragulus and found in Aragon
, Spain
, Ronheim, Germany, and Kazakstan estimated at 55.8—23.03 Ma. Barbouromeryx was discovered in Scotts Bluff, Nebraska and estimated at 23.03 million years. Palaeomerycidae continued to live in the Old World
with fossils of Lagomeryx and Palaeomeryx
feignouxi recovered in Germany
and Slovakia
from the Middle Eocene. In North America Cranioceras
and other Dromomerycinae continued to live until the Late Miocene.
One of the first known members of this group, the Palaeomeryx
, was thought to be a hornless form distantly related to the Giraffids
before paleontologist Miguel Crusafont found remains of the Triceromeryx
in Middle Miocene Spain. This Palaeomeryx-like form carried two ossicone
s over its orbits that were strait and short, similar to those of true Giraffids. However, the most striking feature of the Triceromeryx was the third, Y-shaped appendage that prolonged the occipital bone
at the back of the skull. Discoveries during the 1980s and 1990s has shown a surprising variety in these occipital appendages.
Ampelomeryx
, a genus of Palaeomerycids found at the early Miocen site of Els Casots, Valles-Penedes Basin, Spain, had a three-horned system of appendages similar to those of Triceromeryx. These appendages were, however, quite different with the paired appendages extending laterally over the orbits flat and wide forming an eye-shade, while the third spectacular posterior appendage was about 20 cm (7.9 in) long.
Another species of Triceromeryx, T. conquensis found in La Retama in Spain, showed an even more spectacular appendage — instead of a Y-shaped structure its posterior appendage was T-shaped with the lateral branches expanding toward the front.
In primitive members of the group (e.g. Ampelomeryx) this appendage was a posterior expansion of the occipital bone lying close to the powerful muscles supporting the skull in a normal position, thus suggesting that this appendage were actually used for fighting between males during the breeding season. The reduced shapes of the flat and laterally oriented appendages of later species suggests these were not used in active fighting, instead forming a function of passive display.
The limbs were more similar to those of modern large bovid
s (e.g Buffalo
es) than to those of okapi
s. They probably lived in boggy forests living on soft leaves and aquatic plants (as hinted to by the brachydont
teeth similar to those of primitive Giraffids).
As a group, the Palaeomerycids appear to have formed a successful part of an independent radiation of horned ruminants that diversified into a variety of forms during the early to middle Miocene, with a geographic range reaching from Spain to China. The giraffids seem to have originated from in Asia south of the Alpine belt while the cervoids seem to have originated north of the Alpine belt.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of ruminants (thus being even-toed ungulate
Even-toed ungulate
The even-toed ungulates are ungulates whose weight is borne about equally by the third and fourth toes, rather than mostly or entirely by the third as in odd-toed ungulates such as horses....
s of order
Order (biology)
In scientific classification used in biology, the order is# a taxonomic rank used in the classification of organisms. Other well-known ranks are life, domain, kingdom, phylum, class, family, genus, and species, with order fitting in between class and family...
Artiodactyla), probably ancestral to deer
Deer
Deer are the ruminant mammals forming the family Cervidae. Species in the Cervidae family include white-tailed deer, elk, moose, red deer, reindeer, fallow deer, roe deer and chital. Male deer of all species and female reindeer grow and shed new antlers each year...
and musk deer
Musk deer
Musk deer are artiodactyls of the genus Moschus, the only genus of family Moschidae. They are more primitive than the cervids, or true deer, in not having antlers or facial glands, in having only a single pair of teats, and in possessing a gall bladder, a caudal gland, a pair of tusk-like teeth...
. They lived in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, 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...
, and Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
from the 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...
to 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...
epoch 55.8 to 5.3 Ma, existing for approximately .
The oldest specimens are of Amphitragulus and found in Aragon
Aragon
Aragon is a modern autonomous community in Spain, coextensive with the medieval Kingdom of Aragon. Located in northeastern Spain, the Aragonese autonomous community comprises three provinces : Huesca, Zaragoza, and Teruel. Its capital is Zaragoza...
, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...
, Ronheim, Germany, and Kazakstan estimated at 55.8—23.03 Ma. Barbouromeryx was discovered in Scotts Bluff, Nebraska and estimated at 23.03 million years. Palaeomerycidae continued to live in the Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
with fossils of Lagomeryx and Palaeomeryx
Palaeomeryx
Palaeomeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe and Asia from the Miocene epoch, 16.9—7.25 Ma, existing for approximately .-Taxonomy:...
feignouxi recovered in Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
and Slovakia
Slovakia
The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...
from the Middle Eocene. In North America Cranioceras
Cranioceras
Cranioceras is an extinct genus of artiodactyl from the Miocene to the Pliocene in the United States.-Sources:* After the Dinosaurs: The Age of Mammals by Donald R...
and other Dromomerycinae continued to live until the Late Miocene.
Description
Palaeomerycids were a group of horned, long-legged, heavy, and massive ruminants that could attain a weight of 350 to 500 kg (771.6 to 1,102.3 lb).One of the first known members of this group, the Palaeomeryx
Palaeomeryx
Palaeomeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe and Asia from the Miocene epoch, 16.9—7.25 Ma, existing for approximately .-Taxonomy:...
, was thought to be a hornless form distantly related to the Giraffids
Giraffidae
The giraffids are ruminant artiodactyl mammals that share a common ancestor with deer and bovids. The biological family Giraffidae, once a diverse group spread throughout Eurasia and Africa, contains only two living members, the giraffe and the okapi. Both are confined to sub-saharan Africa: the...
before paleontologist Miguel Crusafont found remains of the Triceromeryx
Triceromeryx
Triceromeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe from the early Miocene epoch, 22.4—20.0 Ma, existing for approximately .It was similar to Ampelomeryx, a herbivore.-Taxonomy:...
in Middle Miocene Spain. This Palaeomeryx-like form carried two ossicone
Ossicone
Ossicones are horn-like protuberances on the heads of giraffes, male okapis, and their extinct relatives, such as Sivatherium, and the climacoceratids, such as Climacoceras. Only giraffids have true ossicones...
s over its orbits that were strait and short, similar to those of true Giraffids. However, the most striking feature of the Triceromeryx was the third, Y-shaped appendage that prolonged the occipital bone
Occipital bone
The occipital bone, a saucer-shaped membrane bone situated at the back and lower part of the cranium, is trapezoidal in shape and curved on itself...
at the back of the skull. Discoveries during the 1980s and 1990s has shown a surprising variety in these occipital appendages.
Ampelomeryx
Ampelomeryx
Ampelomeryx is an extinct genus of herbivorous even-toed ungulate mammal belonging to the family PalaeomerycidaeAmpelomeryx was named by Duranthon et al. . It was assigned to Palaeomerycinae by Prothero and Liter . It had frontal and occipital appendages. It was similar to Tauromeryx and...
, a genus of Palaeomerycids found at the early Miocen site of Els Casots, Valles-Penedes Basin, Spain, had a three-horned system of appendages similar to those of Triceromeryx. These appendages were, however, quite different with the paired appendages extending laterally over the orbits flat and wide forming an eye-shade, while the third spectacular posterior appendage was about 20 cm (7.9 in) long.
Another species of Triceromeryx, T. conquensis found in La Retama in Spain, showed an even more spectacular appendage — instead of a Y-shaped structure its posterior appendage was T-shaped with the lateral branches expanding toward the front.
In primitive members of the group (e.g. Ampelomeryx) this appendage was a posterior expansion of the occipital bone lying close to the powerful muscles supporting the skull in a normal position, thus suggesting that this appendage were actually used for fighting between males during the breeding season. The reduced shapes of the flat and laterally oriented appendages of later species suggests these were not used in active fighting, instead forming a function of passive display.
The limbs were more similar to those of modern large bovid
Bovid
A bovid is any of almost 140 species of cloven-hoofed ruminant mammal at least the males of which bear characteristic unbranching horns covered in a permanent sheath of keratin....
s (e.g Buffalo
Water Buffalo
The water buffalo or domestic Asian water buffalo is a large bovine animal, frequently used as livestock in southern Asia, and also widely in South America, southern Europe, northern Africa, and elsewhere....
es) than to those of okapi
Okapi
The okapi , Okapia johnstoni, is a giraffid artiodactyl mammal native to the Ituri Rainforest, located in the northeast of the Democratic Republic of the Congo, in Central Africa...
s. They probably lived in boggy forests living on soft leaves and aquatic plants (as hinted to by the brachydont
Brachydont
Brachydont is a type of dentition characterized by low-crowned teeth, as opposed to high-crowned, hypsodont teeth. Human teeth are brachydont.-External links:*http://animaldiversity.ummz.umich.edu/site/topics/mammal_anatomy/tooth_diversity.html...
teeth similar to those of primitive Giraffids).
As a group, the Palaeomerycids appear to have formed a successful part of an independent radiation of horned ruminants that diversified into a variety of forms during the early to middle Miocene, with a geographic range reaching from Spain to China. The giraffids seem to have originated from in Asia south of the Alpine belt while the cervoids seem to have originated north of the Alpine belt.
Taxonomy
Palaeomerycidae was named by Lydekker (1883). Its type is Palaeomeryx. It was assigned to Artiodactyla by Hulbert and Whitmore (2006); and to Cervoidea by Carroll (1988), Sach and Heizmann (2001) and Prothero and Liter (2007).Classification
- Amphitragulus
- Dromomerycinae
- Asiagenes
- Aletomerycini
- Sinclairomeryx
- AletomeryxAletomeryxAletomeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to North America from the early Miocene epoch 20.6—16.3 Ma, existing for approximately .-Taxonomy:...
- Dromomerycini
- Drepanomeryx
- Rakomeryx
- Dromomeryx
- Subdromomeryx
- Cranioceratini
- Barbouromeryx
- Bouromeryx
- ProcraniocerasProcraniocerasProcranioceras is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe and Asia from the Miocene epoch, 16.3—13.6 Ma, existing for approximately .-Taxonomy:...
- CraniocerasCraniocerasCranioceras is an extinct genus of artiodactyl from the Miocene to the Pliocene in the United States.-Sources:* After the Dinosaurs: The Age of Mammals by Donald R...
- PediomeryxPediomeryxPediomeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to North America from the early Miocene epoch 10.3—4.9 Ma, existing for approximately .-Taxonomy:Pediomeryx was named by Stirton...
- YumacerasYumacerasYumaceras is an extinct genus of horse-like Artiodactyla, of the family Palaeomerycidae, endemic to North America, Europe and Asia from the Miocene epoch, 13.6—5.33 Ma, existing for approximately .-Taxonomy:Yumaceras was named by Frick...
- Palaeomerycinae
- PalaeomeryxPalaeomeryxPalaeomeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe and Asia from the Miocene epoch, 16.9—7.25 Ma, existing for approximately .-Taxonomy:...
- AmpelomeryxAmpelomeryxAmpelomeryx is an extinct genus of herbivorous even-toed ungulate mammal belonging to the family PalaeomerycidaeAmpelomeryx was named by Duranthon et al. . It was assigned to Palaeomerycinae by Prothero and Liter . It had frontal and occipital appendages. It was similar to Tauromeryx and...
- TriceromeryxTriceromeryxTriceromeryx is an extinct genus of Artiodactyla, of the family Palaeomerycidae, endemic to Europe from the early Miocene epoch, 22.4—20.0 Ma, existing for approximately .It was similar to Ampelomeryx, a herbivore.-Taxonomy:...
- Palaeomeryx