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PHYLUM CHORDATA SUB PHYLUM VERTEBRATA CLASS MAMMALIA Linnaeus, 1758 ORDER PROBOSCIDEA Illeger, 1811 SUB-ORDER ELEPHANTIFORMES Tassy,

1988 SUPER FAMILY ELEPHANTOIDEA Osborn, 1921 FAMILY STEGODONTIDAE Osborn, 1918 SUBFAMILY STEGODONTINAE Osborn, 1918 GENUS STEGODON Falconer, 1857.

Elephants are largest land animals now living.

Two genera of the family Elephantidae: Elephas and Loxodonta.

Three species of elephants are living today: the African bush elephant, the African forest elephant and the Asian elephant.

All other species and genera of Elephantidae are extinct.

The Asian and African elephants diverged from a common ancestor some 7.6 million years ago.

AFRICAN ELEPHANTSingle species with two subspecies.

AFRICAN SAVANNA / BUSH ELEPHANT(Loxodonta africana africana).

AFRICAN FOREST ELEPHANT (Loxodonta africana cyclotis).

Four subspecies. Sri Lankan elephant (Elephas maximus

maximus), only found on the island of Sri Lanka.

Indian elephant (Elephas maximus indicus),found in India.

Sumatran elephant (Elephas maximus sumatranus), found only on Sumatra.

 Borneo pygmy elephant, found only in Borneo.

The African elephant is typically larger than the Asian elephant and has a concave back.

African elephants have larger ears. In Asian elephants, only males have

tusks, but both males and females of African elephants have tusks.

Elephants are now endangered. Today there are about 600,000 African

elephants and 30,000 wild Asian elephants.

There are 170 known fossil elephant species that inhabited the whole Earth, except for Australia and Antarctica.

The elephants' ancestors appeared 50 million years ago in North Africa, were pig sized and resembled a tapir. Elephants' living closest relatives are sea cows, like manatees, dugongs and hyraxes.

During the Ice Age there were more 6-7 elephant species, including mastodons in North America and mammoths in Eurasia and North America.

There are 170 known fossil elephant species that inhabited the whole Earth, except for Australia and Antarctica.

Sadaf

Parameters Tatrot, Pinjor, and Boulder conglomerate stages

Age Boulder Conglomerates 0.5-11000,

Pinjor 3.2-0.5Ma.

Tatrot 3.5-3.2Ma.

Thickness 30-500m.

Type Locality Lies along the road Gali Jagir to Sihal, on the north of Soan River, in District Chakwal.

Principle Exposures Pubbies of Gujrat, Rhotas, Hattar, Kotal Kund, Kala Chitta Range, JARI KAS and Tatrot.

Lithology Conglomerates with subordinate interbeds of greenish grey Sandstone, brown grey Siltstone and great variety of Pebbles. Clay is orange brown in color.

The family Stegodontidae has its origin in the Early Miocene of Asia and is composed of two genera, Stegolophodon and Stegodon.

The genus Stegodon remained largely restricted to Asia, but thrived there throughout the Plio-Pleistocene, with a centre of radiation located in Southern China (Saegusa, 1996).

In the past, stegodonts were believed to be the ancestors of the true elephants and mammoths, but it is currently believed that they have no modern descendants.

Stegodon is derived from the genus Stegolophodon, an extinct genus known from the Miocene of Asia.

Stegodon is considered to be a sister group of the mammoth, as well as the elephants.

Taxon Specimen no.

Position Formation/ Locality

GPS Co- ordinates

Stegodon bombifrons

PUPC No. 2010/16

Skull with palate and right and left molars.

Pinjor (Jari Kas, Mirpur)

33° 06 236 N73° 50 012 E

DP3 4-4½

DP4 5 - 6

M1 6

M2 6 - 7

M3 7½-9½

6 ½-8

7-7½

5½-7

4-4 ½

Uptil now fossils of Stegodon have been recovered from Indonesia, China, Thailand, Japan Africa and pakistan

Cranium compressed anteroposteriorly with convex skull vertex.

Tusks small. Cement gradually increases in the successive

teeth. Enamel very thick. Teeth broad and large. Usually a trace of median longitudinal cleft

present in anterior ridges. Inner columns of ridge-plates occasionally show

accessory tubercles near the longitudinal cleft. Ridge plate formula:

Cement

Palate

Conelets

Dentine

Enamel

Ridge plate

Aneterior side

Posterior side

SPECIES No. of ridge plates

L (mm) W (mm) W/L index

Stegodon dhokawanensis species new.

61/2 183 93 51

S.pinjorensis (From Osborn, 1942).

141/2-1 360 130 36

S. bombifrons(deduced from Falconer, 1968, Lydekker, 1886 and Osborn, 1942.

71/2-91/2 253-282 93-108 37-38

S. insignis (deduced from Falconer, 1868, Lydekker, 1886 and Osborn, 1942).

81/2-111/2 233-287 86-106 37

SPECIES

dP2 dP3 dP4 M1 M2 M3

S. insignis

2 5–6 7 7–8 7–810–11

S. orientalis

3 5–6 6–7 6–7 6–8 11–12

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