module vi: zoogeographical realms

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1 V SEMESTER ZOOLOGY MODULE VI: ZOOGEOGRAPHICAL REALMS Sclater (1857) was the first one to give concepts of zoogeography and divided the continental masses into six Realms based on his studies on the bird fauna under two Creatio or centres of Creation, namely, Palaeogeana (Old world) and Neogeana (New world). Creatio PALAEOGEANA (Old World) Realms PALAEARCTIC (Temperate Eurasia) AETHIOPIAN (West Paleotropic). Africa. INDIAN (Middle Paleotropic). Tropical Asia. AUSTRALIAN 9East Paleotropic). Australia, New Guinea, Tasmania. Creatio NEOGEANA (New World) Realms NEARCTIC (North America). Greenland, North America up to Mexico. NEOTROPICAL (South America). South America south of Mexico. T.H. Huxley (1868) grouped different regions into 3 divisions as follows: NEOGEA (Neotropical). NOTOGEA (Australian). ARCTOGEA (Rest of the Word). A.R.Wallace (1876), who is considered father of modern zoogeography agreed with Sclater’s classification but proposed the name ORIENTAL instead of INDIAN and AFRICAN instead of ETHIOPIAN regions because the earlier names represented countries and not the zoogeographical regions. The widely accepted modern classification of land masses into regions is given below which is based on Wallace (1876) and Darlington (1957). 1. Realm MEGAGEA 1. Region PALEARCTIC (Europe, Russia, Mediterranean). 2. NEARCTIC (North America up to the middle of Mexico). 3. AFRICAN (=ETHIOPIAN) (Africa south of Sahara). 4. ORIENTAL (Tropical Asia south of 30 o latitude). 2. Realm NEOGEA 5. Region NEOTROPICAL (South America, tropical Mexico and Caribbean Islands). 3. Realm NOTOGEA 6. Region AUSTRALIAN (Australia, Tasmania, New Guinea and New Zealand).

Transcript of module vi: zoogeographical realms

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V SEMESTER ZOOLOGY

MODULE VI: ZOOGEOGRAPHICAL REALMS Sclater (1857) was the first one to give concepts of zoogeography and divided the continental masses into six Realms based on his studies on the bird fauna under two Creatio or centres of Creation, namely, Palaeogeana (Old world) and Neogeana (New world). Creatio PALAEOGEANA (Old World) Realms PALAEARCTIC (Temperate Eurasia) AETHIOPIAN (West Paleotropic). Africa. INDIAN (Middle Paleotropic). Tropical Asia. AUSTRALIAN 9East Paleotropic). Australia, New Guinea, Tasmania. Creatio NEOGEANA (New World) Realms NEARCTIC (North America). Greenland, North America up to Mexico. NEOTROPICAL (South America). South America south of Mexico. T.H. Huxley (1868) grouped different regions into 3 divisions as follows: NEOGEA (Neotropical). NOTOGEA (Australian). ARCTOGEA (Rest of the Word). A.R.Wallace (1876), who is considered father of modern zoogeography agreed with Sclater’s classification but proposed the name ORIENTAL instead of INDIAN and AFRICAN instead of ETHIOPIAN regions because the earlier names represented countries and not the zoogeographical regions. The widely accepted modern classification of land masses into regions is given below which is based on Wallace (1876) and Darlington (1957). 1. Realm MEGAGEA 1. Region PALEARCTIC (Europe, Russia, Mediterranean). 2. NEARCTIC (North America up to the middle of Mexico). 3. AFRICAN (=ETHIOPIAN) (Africa south of Sahara). 4. ORIENTAL (Tropical Asia south of 30o latitude). 2. Realm NEOGEA 5. Region NEOTROPICAL (South America, tropical Mexico and Caribbean Islands). 3. Realm NOTOGEA 6. Region AUSTRALIAN (Australia, Tasmania, New Guinea and New Zealand).

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PALAEARCTIC

This region includes Europe, Russia up to pacific coast and Mediterranean up to Sahara. Climate is temperate and polar in the north. Eastern Asia is temperate with deciduous forests. In northern zone there are grasslands (steppe) and interior portion is arid. Mammals. There are 33 families of land mammals. Animals of word-wide distribution which amounts to one-third of families are rabbits, mice dog family, shrews, squirrels and cat family. Animals that are restricted to the Old World include hedge hog, porcupine, civets, giant panda (Ailuropoda), hyena and pigs. Four families are shared with Nearctic: beavers, jumping mice, flying squirrels, mole (Talpa) and four shared with African region. Endemic mammals: mole rat (Spalacidae) and Camel (Seleviniidae), dormice. African elements are wild horses, the prezevalski's horse is the only truly wild horse in the world. Aves. There are 53 families of birds most of which are migratory. All birds have wide distribution and are shared with Nearctic, Oriental and African regions, e.g. pheasants, wrens, finches, warblers, sea birds, geese, birds of prey, cranes, terns, gulls etc. Hedge sparrow is restricted to this region. Reptiles. There is no endemic reptilian family. Lizard, Sinisaurus, and Alligartor sinensis are endemic in China. There are lizards, snakes, Typhlops and sand boa, Trionyx and emydine turtles. Amphibia. There are common newts, crested newt (Triton), Spanish newt and alpine newt. The colourless Proteus is blind and lives in European caves. There are European salamanders, Salamandra salamandra and S. atra and a species of giant salamander (Megalobatrachus) in Japan and China that attains a length of over 5 feet. Anurans are represented by frogs, toads, tree frogs. Male of the midwife toad (Alytes obstetricans), which is found in France and Italy carried eggs wrapped around his hind legs. Amphibians show affinities with Nearctic Region.

Fishes. Fish fauna also shows affinities with Nearctic. There is no endemic fish and carp is the dominant family. There are carps, salmon, pikes, perches, eels and Petromyzon that migrates from sea to the rivers to breed and the ammocoete larva, commonly known as sand sleeper lives in mud for several years in European rivers. Few species of toothless sturgeons immigrate from sea to the rivers of Japan and Russia for laying eggs which are harvested to prepare a delicacy called caviar.

The fauna is a mixture of Old World tropics and New World temperate.

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SUBREGIONS OF PALAEARCTIC

European. Northern and central Europe. Black sea. The fauna hedge hog, shrew, mole and myogale (a mammal).

Mediterranean. Southern Europe. Arabian, Asia Minor, Afghanistan, Baluchistan and parts of Russia. Fauna includes civets, hyena, hyrax.

Siberian. Northern Asia north of Himalaya having extreme climatic conditions. Fauna includes yak, musk deer, mole, freshwater seal (Phoca sibirica) found in Baikal lake.

Manchurian. Mongolia, Japan, Korea, Manchuria, Tibet and northern China. The fauna contains Tibetan langur (Rhinopithecus), giant panda (Ailuropus), Chinese water deer (Hydropotes), tufted deer (Elaphodus).

NEARCTIC This region includes the north American continent up to the middle of Mexico. Climate is temperate with an arctic edge. There are grasslands in the middle of the continent. Western part is arid with mountains and coniferous forests. Mammals. There are 24 families of land mammals. Endemic mammals include rodents, pocket mice (Heteromyidae), pocket gophers (Geomyidae) and mountain beavers (Aplodontidae). Pronghorns and Sewellel (Antilocapridae) are endemic artiodactyls. Palaearctic elements include beavers, moles (Talpidae), pikas and jumping mice. Neotropical species that have crossed over to North America are marsupials such as opossum (Didelphis virginiana), shrew opossum (Lestoros inca); 9-banded armadillo (Dasypus) and tree porcupine. There are some mammals of wide ranging distribution, namely, shrews, rabbits, squirrels, mice, cats, bats, bears, deers and bovids. Birds. There are 49 families of birds in this region out of which 39 are widely distributed. Exclusive birds are: red cardinals, humming birds, tanagers and wild turkeys (Meleagrididae). Golden plover migrates from Europe. Reptiles. There are turtles, non-poisonous garter snakes, rattle snakes, geckos, horned lizards, limbless lizard (Ophisaurus), horned toad (Phrynosoma) and Alligator mississipiensis. Gila monster (Heloderma) is exclusive to this region.

Amphibia. Urodeles include salamanders, hellbender (Cryptobranchus), neotenic larva called axolotl, eel-like siren, the Congo eel (Amphiuma) and tiger salamanders, Ambystoma tigrinum. Newts include Smooth newt, great crested newt, banded newt,

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alpine newt, Bosca’s newt. There are dusky salamanders, red-backed salamander and Jordan’s salamander.

Anurans include American Bell toad, Liopelma, North American bull frog and Leopard frog found in grassy meadows. Rana cascadae and Bufo boreas inhabits Cascade Mountains of Oregon, USA. The desert spade-foot toad is adapted to the arid climate of northwestern America. Other toad species are: Oak toad, southwestern toad and the giant toad which is 20 cm long.

Fishes. There are many carps (Cyprinidae) and perches. Holostei are endemic that include only two surviving ganoid fishes, one species of bowfin (Amia calva) found in American lakes and 7 species of garpike (Lepidosteus) found in American rivers. These fishes possess sharp teeth to seize and gulp prey with extraordinary swiftness. Paddlefish (Polyodon) occurs in Mississippi river of America and represents Chondrostei. Another species of paddlefish occurs in China. These fishes have paddle-like snout that carries sensory organs for locating prey by detecting its electrical fields. Ameiurid catfishes, moon-eyes (Hiodontidae) and bass family with genera Morone and Upiblema are also endemic.

The fauna of Nearctic Region is rich in reptiles and is a complex of tropical and temperate animals. SUBREGIONS OF NEARCTIC Californian. Narrow strip between Sierra Nevada and Cascade Range. From Vancouver to British Columbia. Fauna includes 86 families of vertebrates that include vampire and free-tailed bats. Rocky Mountains. This includes dry mountainous region east of California. Fauna contains 107 families of terrestrial vertebrates. There are pronghorns (Antilocapra), mountain goat (Haplocerus), American bison, prairie dogs (Cynomus) and Heloderma. Alleghany. This includes eastern region of USA. The fauna includes opossum, starnosed mole, vampire bats, turkeys and mud eel (Siren). Canadian. This sub region includes Canada, Greenland and Alaska. The fauna is poor and resembles palaearctic region. There are reindeer, sheep, bisons, lemmings, polar beer, elk and arctic fox.

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AFRICAN REGION

This region includes continental Africa south of Sahara desert. This is mainly a tropical region having evergreen forests and grasslands in the central and eastern parts. There is desert in the north. Mammals. There are 38 families of mammals, out of which 12 are exclusive and the rest are shared with Neotropical and Oriental Regions. Animals having worldwide distribution include shrews, rabbits, squirrels, cricetid mice, dogs, mired mice, cats and bovids, antilopes. The exclusive animals include giraffes, hippopotamus, Aardvark or Cape anteater belonging to Tubulidentata, rock hyrax (Hyracoidea), golden mole (Chrysochloridae), elephant shrew, small deer-like water chevrotain, aye-aye, bushbabies and lemurs in Madagascar. There are 6 endemic families of rodents and 3 of insectivores. There are no camels, bears and tigers in this region. Animals shared with Oriental are, lorises, monkeys, apes, pangolins, Cheetah, elephants and rhinoceroses. Shared with Palaearctic are dormice, jerboa (Dipodidae), wild horses. Aves. Bird fauna has affinities with Oriental Region. There are cuckoos, woodpeckers, hornbill, sunbirds, herons, orioles, birds of prey, storks, parrots, pigeons, fowls, pitta, guinea fowl, hornbill, swallows and bee-eaters. There are 6 exclusive families that include ostrich, secretary bird (Secretariidae), hammer head that feed on frogs and fish, crested touracos (Turacidae), ground hornbill, mouse birds and helmet shrike. Honey guide feeds on honey bee larvae and guides honey collecting tribals to bee hives. Two species of oxpeckers, namely, yellow billed and red billed feed on ticks and other ectoparasites of rhinoceroses. The crocodile bird dares to enter the mouth of crocodiles to feed on leeches. Reptiles. Crocodiles and turtles abound and few lizards belong to families Lacertidae and Agamidae. Iguanid horned lizards are absent. Spiny lizard of family Cordylidae is restricted to this region. Chameleon also occurs in the Oriental Region. Snakes include pythons, Typhlops and biting vipers. Crocodiles include, Crocodylus noloticus, Osteolaemus in West Africa and Osteoblepharon in Congo. Amphibia. There are no urodeles but frogs and toads abound such as the African ridged frog and African shovel-nosed frog. Family Hylidae of tree frogs is absent, replaced by Polypedatidae. The flying frog is the African rhacophorid. Genera Rana and Bufo are absent. Phrynomerid tree frogs are endemic. Xenopus and aquatic clawed toads present. Limbless amphibians are present. Fishes. Lung fishes have two species of Protopterus that live in the rivers and lakes of tropics. Chondrostei is represented by 10 species of Bichir (Polypterus). Electric eel of

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family Mormyridae has electric organs in tail. There are cat fishes, carps, characins and generally the fish fauna is diverse. Fauna shows overwhelming similarity with the Oriental Region. SUBREGIONS OF AFRICAN REGION 1. East African. This includes tropical Africa and tropical Arabia. Fauna contains 145 families of vertebrates. There are rhinoceros, zebra, giraffe, cheetah, spotted hyena and lions. 2. West African. Western Africa up to Congo includes forests. Fauna has 134 families of vertebrates that include, gorilla, chaimpanzee, monkeys, baboons, flying squirrel. 3. South African. Southern portion of Africa. Fauna contains 133 families of vertebrates. There are ostriches and secretary birds. Mammals include golden mole, elephant shrew, jumping mice, aardvark and naked mole rat that leads subterranean existence. 4. Malagasy. Madagascar, Mauritius, Seychelles and neighbouring islands. Fauna has 86 families out of which 8 are endemic. There are aye-aye, lemurs and common tenrec (Tenrec ecaudatus). Helmet birds and cuckoo rollers and rough-tailes snakes (Uropeltidae) are endemic. The flightless bird Dodo which was related to flightless pigeon became extinct in 1681 due to hunting by man and egg predation by dogs, pigs and monkeys.

ORIENTAL REGION

This region includes Indian subcontinent, southern China south of 30o latitude, Malaya, Philippines and Indonesian islands up to Wallace’s Line. There are rain forests in the east, high mountains in the north and the western part is arid. Along the south-western coast there is a forested low mountainous belt. Mammals. There are 30 families of mammals out of which 5 are endemic that include Cynocephalus (=Galeopithecus), which is called Calugo, a gliding mammal with furred membrane stretched between fore limb and hind limb. Tree shrews (Tupaiidae) and arboreal tarsiers (Tarsiidae) of Philippines are restricted primates. Spiny dormouse is arboreal rodent. Twenty five percent of the fauna is shared with Africa that includes, old world monkeys, lorises, apes (Gibbon and Orang-Utan), pangolin or scaly anteater (Manis), bamboo rat (Rhizomyidae), Elephant (Elephas maximus), Rhinoceros unicornis and a lion population in Gir forest. Fauna shared with Palaearctic includes hedge hog, porcupine, civets, Lynx, hyenas, pigs, bear (Ursus arctos), red panda. Tapir (Tapirus) found in Sumatra and Borneo is Neotropical element. There are moles, tapirs, bears and deers which are absent in Africa.

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Aves. Out of 66 families of birds 53 are eurytopic or widespread. Woodpeckers and barbets are widespread. There are also peacocks, argus pheasants, cattle egrets (Bubulcus ibis) and jungle fowl. Sunbirds, hornbills, parrots and cuckoos and shared with Africa. Shared with Palaearctic are pheasants. Exclusive birds are fairy blue bird (Irena puella) which is found in Philippines where it follows troupes of monkeys to feed on insects disturbed by their movement. There are 4 genera and 14 species of leaf birds. Whitehead’s trogon (Harpactes whiteheadi) is found in Indonesia and monkey-eating eagle is endangered species found in the dense forests of Philippines. Reptiles. There are plenty of lizards, turtles, poisonous snakes, pythons and crocodiles. Lizards belong to Agamidae and Varanidae and include geckos, skinks, calotes, draco and chameleon. There are king cobras, common cobras, typhlops, xenopeltid snakes, uropeltid snakes and sea snakes (Hydophidae). Crocodiles include Crocodylus porosus, C. palustris, Gavialis gangeticus. Tomistoma is found in Sumatra and Borneo. Alligator sinensis is found in southern China. Amphibia. Frogs and toads bound. Caecilians are represented by Ichthyophis and Gegenophis found in Indo-Malayan region. Tree frogs belong to family Polypedatidae and Hylidae family is absent. Flying frog, Rhacophorus malabaricus found in Western Ghats in India. Tailed Amphibia are few and found in northern Indo-china. Fire-bellied toads are exclusive and extend to Palaearctic range. Fishes. Fishes are dominated by carps and catfishes (Cypriniformes). Loaches, mullets and mud-eels are exclusive to this region. One species of the Chondrostean paddlefish (Polyodon) occurs in Yangtze River of China. Another species of this group occurs in American rivers. Fauna shows similarity with the Ethiopian Region because of their proximity and similar environmental conditions. SUBREGIONS OF ORIENTAL REGION 1. Indian. Indian subcontinent up to the foot of Himalaya and south up to Mysore. East and Western Ghats are tropical rain forests. There are rocky hills in the central part and desert in the north-west. Fauna is varied. Tibetan Wild Ass found in Ladakh and Himachal Pradesh. Wild Ass found in Runn of Kutch. Golden Langur (Presbytes geei) found in Assam. Indian Pangolin (Manis crassicauda) and great Indian Bustard (Ardeotis nigriceps). 2. Indo-Ceylonese. Sri Lanka and southern parts of India containing Tamil Nadu and Kerala.

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Fauna includes lorises and elephants. Slender Loris (Loris tardigradus), slow loris (Nycticebus caucang), lion-tailed monkey (Macaca silenus) and giant squirrel (Ratufa macroura). 3. Indo-Chinese. China south of 30o latitude, Burma and Thailand. Fauna includes panda, gibbons (Hylobates), flying lemur, lynx, bear (Ursus), Chinese pangolin, red panda, snow leopard (Panthera uncia) and clouded leopard. Red-shanked douc langur is completely arboreal and endemic to Southeast Asia and Cat Ba Langur is endemic in Vietnam. There are Indo-Chinese warty pig and Javan warty pig, Sumatran and Annamite striped rabbits.

Crested Argus pheasant (Rheinardia ocellata) is endemic to Laos and Vietnam and possesses 70 inches long tail feathers, longest for any bird in the world.

Rhinoceros snake (Rhynchophis boulengeri), the green, arboreal snake and green pricklenape lizard (Acanthosaura capra) are endemic to Indo-china.

Whipping frog (Polypedates dugritei) also present.

4. Indo-Malayan. Malayan peninsula and islands of Malay Archipelago and Indonesia. Fauna includes Orang-Utan, proboscis monkey, Malayan badger, Tupaia, gibbons, flying lemurs, tapirs and broad bills. Rhinoceros sondaicus is the lesser one-horned rhinoceros which is found in Java and Rhinoceros unicornis is found in India and Tarai regions of Nepal. Swamp deer (Cervus duvauceli).

NEOTROPICAL

South America, most of Mexico, West Indies, Caribbean islands. Mostly tropical but the southern part extends into temperate zone. Rain forests on the western side. Grasslands in the middle in Argentina. Andes mountain on the western coast. Mammals. There are 32 families of mammals of which 16 are unique. Widely distributed animals are shrews, rabbits, squirrels, mice, dogs, bears, cats and deers. Camels are represented by two species of Llama: L. vicuna and L. guanaco. Llama and Alpaca are domesticated breeds of these species. There are three species of tapirs of which one species also occurs in the Oriental Region. Monkeys include: spider monkeys, squirrel monkeys, howlers, capuchin, marmosets which belong to families Cebidae and Hapalidae of suborder Platyrrhina. Endemic mammals include, six-banded armadillo (Euphractus), armadillo (Dasypus), two-toed sloth (Choloepus), 3-toed sloth (Bradypus), 3 species of anteaters,(Myrmecophaga), 11 endemic families of rodent Caviomorpha and five

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endemic families of bats that include disc-winged bats, furipterid bats and vampire bats (Desmodontidae), the last one is also a carrier of rabies. Marsupials belong to the family Didelphidae (12 genera) that includes common opossum (Didelphis) and water opossum (Chironectes) and family Coenolestidae (3 genera) includes opossum rat (Ceonolestes). The common opossum has also spread to the Nearctic Region where it has adapted to varied climatic conditions. There are no hedgehogs, moles, beavers, hyenas, bovids and horses in this region.

Aves. Almost 50% of the avian fauna is endemic and unique due to which South America is known as The Bird Continent. Out of 67 families of birds, 25 are endemic to the region. There are partridge-like tinamous, toucans that carry enormous beaks, trumpeters, hoatzin, cock of the rock (Rupicola), oil birds and several species of macaws, such as yellow macaw, Hahn’s macaw, red bellied macaw and red and blue macaw. Quail is the only member of Galliformes here. Bee hummingbird found in Cuba measures only 6 cm and is the smallest bird.

Ostriches are represented by Rhea americana.

Common birds include herons, ibis, storks, ducks, hawks, owls, plover, cuckoos. There is scarcity of song birds.

Reptiles. There are plenty of snakes, iguanid lizards, Crocodilus, Caiman (alligator) and turtles. Xantusiid lizards are endemic. There are tree boas, anacondas, pit vipers and coral snakes. Mud turtles (Pelomedusidae) are shared with Africa and snake-neck turtles, Chelodina (Chelidae) with Australia.

Amphibia. There are hylid tree frogs such as Brazilian tree frog Hyla, Hylodes, Cuban tree frog, Venezuelan tree frog that deters predators by foul odour and the poisonous Phyllomedusa found in Amazon. Leptodactylus deposits its eggs in frothy mass in holes on muddy banks of rivers and ponds and Hyla faber makes crater-like nests. The Tungara frog is noisy and makes foam nests. Tiny frogs belong to the genera Phyllobates, Dendrobates and Agalychnis. The yellow frog is the largest and most toxic and its poison is used by Colombia tribes to poison their blowgun darts. The dart poison frog is also highly poisonous. The tongue and toothless Surinam toads show parental care. The small Chilean frog carries eggs in the gular pouch while the Brazilian tree frog, Hyla goeldii carries eggs on the back. Caecilians are represented by Typhlonectes. Oedipus is the only tailed amphibian (Urodela) found in South America.

Fishes. There are no carps (Cyprinidae) and other fish fauna is endemic. There is electric eel (Gymnotidae), cat fishes (Diplomystes, Nematogenys) and characin fish (Piranhas). Lung fishes are represented by Lepidosiren paradoxa found in Amazon River.

The fauna of Neotropical Region is rich in endemic families; almost 40 families are endemic out of 155 families of vertebrates. Other fauna is shared with Nearctic and other tropics.

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SUBREGIONS OF NEOTROPICAL

Chilian. Western coast of South America, embracing summits of Andes, Peru and Bolivia. Fauna includes chinchilla, Llama, oil birds and Rhea.

Brazilian. Tropical forests up to Isthmus of Panama. Also open plains and pasture lands. Fauna includes New World Monkeys, vampire bats, tree porcupine, sloths, armadillo, opossum, tapirs, cavia, spiny mice.

Mexican. Mexico and northern lands of isthmus of Panama and rocky mountains. Fauna includes mud terrapins, tapirs and Plethodontids.

Antilean or West Indies. Caribbean Islands except Tobago and Trinidad. Contains mountainous and rocky areas covered with forests. Fauna is poor and native mammals are absent.

AUSTRALIAN This region includes Australia, Tasmania, New Guinea, New Zealand and islands east of Wallace’s Line. New Guinea is tropical with rain forests. Eastern Australia is covered with lush green forests, Western Australia is desert and there are grasslands in the middle. Mammals. Eight of the 9 families of marsupials are unique. There are 52 genera of 6 families of marsupials that are unique and are not found in the Neotropical Region. Marsupials show parallelism with their counterpart placentals in other parts of the world in their evolutionary modifications. Placental mammals that were introduced by man or some of them immigrated themselves include rodents and bats, rabbits, foxes, rats, mice, dingo dogs, cats, pigs and murid mice. Monotremes are represented by Ornythorhynchus and Echidna. Birds. There are 58 families of birds out of which 44 are widely distributed. Species having wide range are trogons (Harpactes), hawks, kingfisher, cuckoos, parrots and pigeons. Shared with Oriental are frogmouths, wood-swallows, flowerpeckers and megapods. There are 10 families of endemic birds which include cassowary, emu, kiwi, lyrebird, bower birds, honey suckers, birds of paradise, magapods and cookabura or laughing jackass that feeds on lizards and snakes. Birds not present are pheasants, finches, barbets and woodpeckers. Reptiles. There are pythons, biting snakes, elepid coral snakes, geckos, skinks, agamid lizards, scale-footed lizard (Pygopus) and Komodo Dragon (Varanidae), crocodiles and turtles. Chelyd turtles and snake-necked turtles (Chelodina) possess strikingly long necks. Sphenodon pounctatus is found exclusively in New Zealand.

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Amphibia. There are no tailed amphibians. Common toads are absent and frogs are few. Tree frogs belong to family Hylidae which is also found in the New World and Palaearctic but absent in African and Oriental Regions. The Australian Green Tree Frog secretes mosquito repellent compound from the skin glands. The Australian frogs, Rheobatrachus silus and R. vitellinus carry tadpoles in their stomachs. Some species of frogs are adapted to live in deserts, e.g. Notaden, Neobatrachus and Helioporus. Fishes. Fresh water fishes are rare and belong to family Osteoglossidae. Lung fish (Neoceratodus) is restricted to Burnett and Mary rivers in Queensland. Fauna of this region is poor in freshwater fishes, Amphibia and reptiles. There is uniqueness of mammals and affinities exist with the Oriental and South American faunas. SUBREGIONS OF AUSTRALIAN 1. Australo-Malayan. Malayan Archipelago, Moluccas, Solomon Islands, New Guinea. Fauna includes 130 families of vertebrates. Birds are crowned pigeons, birds of paradise, honey eaters, cuckoos, bover birds, cassowaries. There are fly river turtles, flying phalangers and tree frogs. 2. Australian. Australia and Tasmania. There are 98 families of vertebrates and the region is home of monotremes and marsupials. Monotremes include short-nosed echidna, long-nosed echidna and duck-billed platypus. Marsupials include marsupial rat kangaroos, Tasmanian devil, koala, the horny possum, marsupial mole and rabbit-eared bandicoot. Tasmanian wolf (Thylacinus cynocephalus) became extinct in 1936. There are scrub birds, lyre birds, emus and plenty of cobras. Tailed amphibians are absent. 3. Polynesian. Polynesia and the adjoining islands. Fauna is poor containing only 53 families. Tooth-billed pigeon is unique. 4. New Zealand. New Zealand, Norfolk Island, Auckland and Campbell Island. Fauna includes murid bats, owl parrots, nester parrots, kiwi, Sphenodon and frog (Liopelma). Flightless owl parrot or Kakapo feeds on leaves, shoots, berries, fruits and moss. The only carnivorous parrot called KEA was a vegetarian earlier but after introduction of sheep in New Zealand has learnt to cut sheep skin and feed on flesh. Giant Moa (Dinornis maximus) that reached a height of 3 metres contained 22 species in New Zealand which became extinct all by 1600 AD.