There are two species of echidna. The short-beaked echidna (Tachyglossus aculeatus) lives in Australia and the lowlands of New Guinea. The long-beaked echidna (Zaglossus brujnii) lives in the highlands of New Guinea.
Animals related to the echidna
The echidna is a member of the order Monotremata, of which there is one other member. The table below shows these animals relation to each other.
  Long-beaked echidna Short-beaked echidna Platypus Fossil 'platypus'
Phylum Chordata Chordata Chordata Chordata
Sub-Phylum Vertebrata Vertebrata Vertebrata Vertebrata
Class Mammalia Mammalia Mammalia Mammalia
Order Monotremata Monotremata Monotremata Monotremata
Family Tachyglossidae Tachyglossidae Ornithorhynchidae Ornithorhynchidae
Genus Zaglossus Tachyglossus Ornithorhynchus Obdurodon
Species bruijnii aculeatus anatinus insignis
The name Monotreme comes from the fact that the echidnas and the platypus use the same opening for reproduction and eliminating waste products, which is an attribute that is found in reptiles (Encyclopaedia Britannica, 1995). Other reptilian characteristics include the ability to lay eggs, cervical ribs, and that there is "localisation of ascorbic acid synthesis in the kidney (Serena, 1994; p.118).
The long-beaked echidna is found in the humid mountain forests of Papua New Guinea and Irian Jaya. The short-beaked echidna is more widely dispersed and can be found throughout Australia and parts of Papua New Guinea. Whereas the platypus is only found in the Eastern parts of Australia.
Differences between Echidna, Porcupines, and Hedgehogs
Relatives Belong to Order Rodentia., Relations are guinea pigs, chinchillas, rats. Moles, shrews and tenrecs. Order Insectivora (insect eaters).
Location N & S America, Europe, Africa and Asia. Close relatives found in Europe, Africa, Philippines, Sumatra, Egypt, & Gobi desert to N China., European hedgehod introduced to NZ.
Diet Bark, roots, tubers, bulbs, seeds, leaves, sometimes insects. Frogs, snakes, lizards, young birds, mice, insects.
Quills & ProtectionSpines not barbed, different lengths & thickness. Fixed to skin. Spines can be moved individually. Roll up - prefer to dig down to present spiny back.Hollow & barbed. Sit loosely on skin and detach and stick in intruder who comes too close.Short spines. Not barbed. Fixed to skin. Roll into ball.
Mouths and facesBirdlike beak - part of skeletal structure. Touch hairless skin covering it. Teeth. Chew. Small, button-like noses.Tiny sharp teeth., Voracious appetites. Small, button-like noses.
FeetQuadruped. Hind feet - outward & rotated back.Quadruped. Hind feet - point forward.Quadruped. Hind feet - point forward.
(Table adapted from Rismiller, 1999)
Description & Behaviour
The echidna uses its to pick up food. It does this by flicking it out and then quickly pulling it back into its mouth. 
The echidna's skull is similar to that of a bird's rather than a mammal's. This is because the echidna's beak is part of the bone structure of the skull.
Echidna spines are hairs that have adapted.  They are not barbed.
Feet & Claws
Stomach & Digestion
Reproductive Organs
Mammary Glands
General behaviour
The echidna is able to swim across water.  
Body temperature
Diet & Feeding
Long-beaked Echidna
Short-beaked Echidna
Gunduwa is the Wadjarri name for the short-beaked echidna.
Social Aspects
Environmental Influences
Ancestry & History
The oldest order of mammals is Monotremata. Etienne Geoffrey Saint-Hilaire (1803) came up with the name Monotremata (Mono = one, tremata = hole). He felt that there were significant enough differences between the monotreme and the mammals & reptiles that justified them being a class of their own.
Encyclopaedia Britannica. 1995
Rismiller, P., 1999.The Echidna: Australia's Enigma. Hong Kong: Hugh Lauter Levin Associates. Inc
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