Boselaphini | |
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Nilgai | |
Four-horned antelope | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Artiodactyla |
Family: | Bovidae |
Subfamily: | Bovinae |
Tribe: | Boselaphini Knottnerus-Meyer, 1907 |
Genera | |
and see text. |
Boselaphini is a tribe of bovines. It contains only two extant genera, each with a single extant species.
The Boselaphini or four-horned antelope tribe are the last survivors of a form very similar to that of the ancestors of the broader subfamily. The oldest fossil members of the tribe, such as Eotragus , date to the Miocene about 18 to 20 million years ago. Such fossils possessed horns very similar to those of males belonging to the two living species, although in some cases, they were also present in females. [1]
Both extant species have relatively primitive anatomical and behavioural characteristics and the females have no horns. They are native to the rapidly diminishing forests of India, and tend to avoid open plains. The nilgai has been introduced into southern Texas where a population of a little under 15,000 animals provides some long-term insurance for its survival.[ citation needed ]
Image | Genus | Species |
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Boselaphus Blainville, 1816 |
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Tetracerus Leach, 1825 |
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The following are the genera classified under the tribe. Genera marked with † are extinct. [2]
Tribe Boselaphini
Artiodactyls are placental mammals belonging to the order Artiodactyla. Typically, they are ungulates which bear weight equally on two of their five toes. The other three toes are either present, absent, vestigial, or pointing posteriorly. By contrast, most perissodactyls bear weight on an odd number of the five toes. Another difference between the two orders is that many artiodactyls digest plant cellulose in one or more stomach chambers rather than in their intestine. Molecular biology, along with new fossil discoveries, has found that cetaceans fall within this taxonomic branch, being most closely related to hippopotamuses. Some modern taxonomists thus apply the name Cetartiodactyla to this group, while others opt to include cetaceans within the existing name of Artiodactyla. Some researchers use "even-toed ungulates" to exclude cetaceans and only include terrestrial artiodactyls, making the term paraphyletic in nature.
The term antelope refers to numerous extant or recently extinct species of the ruminant artiodactyl family Bovidae that are indigenous to most of Africa, India, the Middle East, Central Asia, and a small area of Eastern Europe. Antelopes do not form a monophyletic group, as some antelopes are more closely related to other bovid groups, like bovines, goats, and sheep, than to other antelopes.
Bovines comprise a diverse group of 10 genera of medium to large-sized ungulates, including cattle, bison, African buffalo, water buffalos, and the four-horned and spiral-horned antelopes. The members of this group are classified into loose tribes rather than formal subgroups, as the evolutionary relationships within the groups are still uncertain. General characteristics include cloven hooves and usually at least one of the sexes of a species having true horns. The largest extant bovine is the gaur.
The subfamily Caprinae, also sometimes referred to as the tribe Caprini, is part of the ruminant family Bovidae, and consists of mostly medium-sized bovids. A member of this subfamily is called a caprine.
The Bovidae comprise the biological family of cloven-hoofed, ruminant mammals that includes cattle, bison, buffalo, antelopes, sheep and goats. A member of this family is called a bovid. With 143 extant species and 300 known extinct species, the family Bovidae consists of 11 major subfamilies and thirteen major tribes. The family evolved 20 million years ago, in the early Miocene.
The Giraffidae are a family of ruminant artiodactyl mammals that share a recent common ancestor with deer and bovids. This family, once a diverse group spread throughout Eurasia and Africa, presently comprises only two extant genera, the giraffe and the okapi. Both are confined to sub-Saharan Africa: the giraffe to the open savannas, and the okapi to the dense rainforest of the Congo. The two genera look very different on first sight, but share a number of common features, including a long, dark-coloured tongue, lobed canine teeth, and horns covered in skin, called ossicones.
The four-horned antelope, also called chousingha, is a small bovid antelope native to central, South and Western India, along with a smaller population in Nepal. The sole member of the genus Tetracerus, the chousingha was first described in 1816 by French zoologist Henri Marie Ducrotay de Blainville. Three regional subspecies are currently recognised. The four-horned antelope has a yellowish-tan, sometimes reddish or goldenrod coat. It is slender with thin legs and a short tail. It stands nearly 55–64 cm (22–25 in) at the shoulder and weighs about 17–22 kg (37–49 lb). Its four horns are unique among antelopes and distinguish it from most other bovids. The longer pair of straight, spike-like horns is atop its head between the ears, while the other, shorter pair is on the forehead; its posterior horns are always longer than the anterior horns, which may even present as merely fur-covered "studs". While the posterior horns measure 8–12 cm (3.1–4.7 in), the anterior ones are usually 2–5 cm (0.79–1.97 in) long.
The nilgai is the largest antelope of Asia, and is ubiquitous across the northern Indian subcontinent. It is the sole member of the genus Boselaphus, which was first described by Peter Simon Pallas in 1766. The nilgai stands 1–1.5 m (3.3–4.9 ft) at the shoulder; males weigh 109–288 kg (240–635 lb), and the lighter females 100–213 kg (220–470 lb). A sturdy thin-legged antelope, the nilgai is characterised by a sloping back, a deep neck with a white patch on the throat, a short crest of hair along the neck terminating in a tuft, and white facial spots. A column of pendant coarse hair hangs from the dewlap ridge below the white patch. Sexual dimorphism is prominent – while females and juveniles are orange to tawny, adult males have a bluish-grey coat. Only males possess horns, 15–24 cm (5.9–9.4 in) long.
Boselaphus is a genus of bovid. The nilgai is the sole living representative, although one other species is known from the fossil record.
Antilope is a genus of twisted-horn bovid that contains a single living species, the blackbuck of South Asia. Two extinct species are also known.
Pecora is an infraorder of even-toed hoofed mammals with ruminant digestion. Most members of Pecora have cranial appendages projecting from their frontal bones; only two extant genera lack them, Hydropotes and Moschus. The name "Pecora" comes from the Latin word pecus, which means "cattle". Although most pecorans have cranial appendages, only some of these are properly called "horns", and many scientists agree that these appendages did not arise from a common ancestor, but instead evolved independently on at least two occasions. Likewise, while Pecora as a group is supported by both molecular and morphological studies, morphological support for interrelationships between pecoran families is disputed.
The Antilocapridae are a family of ruminant artiodactyls endemic to North America. Their closest extant relatives are the giraffids. Only one species, the pronghorn, is living today; all other members of the family are extinct. The living pronghorn is a small ruminant mammal resembling an antelope.
Taurotragus is a genus of giant antelopes of the African savanna, commonly known as elands. It contains two species: the common eland T. oryx and the giant eland T. derbianus.
The tribe Bovini or wild cattle are medium to massive bovines that are native to Eurasia, North America, and Africa. These include the enigmatic, antelope-like saola, the African and Asiatic buffalos, and a clade that consists of bison and the wild cattle of the genus Bos. Not only are they the largest members of the subfamily Bovinae, they are the largest species of their family Bovidae. The largest species is the gaur, weighing up to 1,500 kg (3,300 lb).
The tribe Tragelaphini, or the spiral-horned antelopes, are bovines that are endemic to sub-Saharan Africa. These include the bushbucks, kudus, and the elands. The scientific name is in reference to the mythical creature the tragelaph, a Chimera with the body of a stag and the head of a goat. They are medium-to-large, tall, long-legged antelopes characterized by their iconic twisted horns and striking pelage coloration patterns.
Eotragus is an extinct genus of early bovid. Species belonging to the genus inhabited Europe, Africa, and Asia during the Miocene some 20-18 million years ago. It is related to the modern nilgai and four-horned antelope. It was small and probably lived in woodland environments.
A gazelle is one of many antelope species in the genus Gazella. There are also seven species included in two further genera; Eudorcas and Nanger, which were formerly considered subgenera of Gazella. A third former subgenus, Procapra, includes three living species of Asian gazelles.
Duboisia santeng or Dubois' antelope is an extinct antelope-like bovid that was endemic to Indonesia during the Pleistocene. It went extinct during the Ionian stage of the Pleistocene, about 750.000 years ago. Duboisia santeng was first described by the Dutch paleoanthropologist and geologist Eugène Dubois in 1891.
Tragoportax is an extinct genus of bovid ungulate. It lived from the upper Miocene to the earliest Pliocene, and its fossils have been found in southeastern Europe, parts of Africa, and the Indian subcontinent. Tragoportax was formerly considered a close relative of the extant nilgai, though more recent studies suggest that it, and several other Miocene "boselaphins", formed a tribe of their own. The number of Tragoportax species has varied over the years, and some have been reassigned to the related genus Miotragocerus. The first Tragoportax specimens were discovered in Greece, and were originally assigned to Capra. Subsequently, they were reassigned to Tragocerus. This genus name was preoccupied by a beetle, and thus Tragoportax is the correct name.
Tragoportacini is a tribe of extinct bovines that first appeared during the Late Miocene and persisted into the Early Pliocene.