(Names such as marsupial wolf, marsupial dog, zebra dog, and Tasmanian wolf reflect this analogy.)  This applies primarily to the shape of the head (especially the morphology of the skull) and the elongated body with its long tail.  The animal's body structure and position of the legs are also rather congruous with that of a placental wolf, although the thylacine's legs are proportionately shorter.  The feet bear blunt, non retractile claws.

. A thylacine in the London Zoo, circa 1909.

    Early European settlers in Tasmania are the originators of names such as marsupial wolf, pouched wolf, and native wolf.   In recent times, the name thylacine has come into more popular use, deriving from the animal's scientific nomenclature.  In older literature, one sometimes encounters names such as "opossum hyena", "native hyena" and "zebra opossum".  Today, Tasmanian tiger is one of the most commonly used names for the species.  This is likely one of the oldest names, as even the Dutch helmsman Jacobszoon (who explored Tasmania in 1624) made mention of the footprints of a "tyger".  Further descriptions of the Tasmanian "tiger" are found in the ship logs of the Dutch East India Company, and the convicts of the penal colony created in 1803 at Derwent River were familiar with the "native tiger".  The Aboriginal people of Tasmania called the thylacine coorinna, loarinna, laoonana, or lagunta.  These native names did not achieve any common usage and disappeared with the European-induced extinction of the Tasmanian Aboriginals.  G. P. Harris, who authored the scientific description of the thylacine, focused on the structure of the animal's head and in 1808 named the species Didelphis cynocephala, which translates to "dog-headed opossum".
 

. One of a number of images taken from a 1928 motion film of a thylacine that was kept at the Hobart Zoo (Domain site).

The genus name of three opossum species, Didelphis, was at first applied to most marsupials, including the wombat (Didelphis ursina) and Brush-tailed opossum (Didelphis vulpecula). The Parisian zoologist E. Geoffroy Saint-Hilaire, in 1809, assigned the thylacine to the genus Dasyurus along with the marsupial "martens" (quolls).  Unsatisfied with this classification, Conrad Jacob Temminck created (in 1824) the genus name that we use today, Thylacinus.  The species name established by G.P. Harris (cynocephalus) remains valid.

    In regard to the biology and behaviour of the thylacine, reliable information is rather rare, so truth and anecdote cannot always be easily separated.  In contrast, data on anatomy and body form can provide a more reliable image of the animal.  The length of the body, from the tip of the nose to the tip of the tail, ranges between 4-6½ ft. (1230-1950 mm), of which about a third, 15-26 in. (380-260 mm), is the tail.  On average, males are somewhat larger than females.  Measurements taken of 18 skeletons largely support these figures.  Shoulder height is 14-24 in. (350-600 mm), but the highest point of the body is over the pelvis.  When running, the hindlimbs are bent at various angles, especially at the ankle.

    Data on thylacine weight is quite rare, and some of this information comes from animals that were kept in zoos.  A body weight of 33-66 lb. (15-30 kg) is estimated.  When running, the tail swings about rather stiffly.  The thylacine's 13-19 dark transverse stripes contrast markedly with the light grey to yellow-brown coat colour.  These markings begin just behind the shoulder, gradually increase in width and length towards the hindquarters, terminating around the base of the tail.  The largest stripe is on the thigh, and ends just above the knee, often splitting at the tip.
 

What appear to be very faint stripes can sometimes be seen on the tail.  However, these are not actually pigmented markings, but an effect of light and shadow across the individual joints of the tail when viewed from certain angles.  The form of the thylacine's stripe pattern is remarkably similar to that of the African Zebra duiker (Cephalophus zebra).  There are light areas around the base of the ears, near the eyes, and occasionally between the forelegs, but they are not as pronounced as the characteristic stripes.  Several authors have pointed out the analogies of body proportions between the thylacine and the placental wolf.  Moeller (1972) clearly demonstrated that the limb length of the thylacine did not exhibit the structural adaptations observed in canids, which subdue their prey by means of a high speed chase.

. The African Zebra duiker (Cephalophus zebra), also known as the Striped-backed duiker.  A small, forest-dwelling antelope, this is one of only a few other living mammal species which bears a stripe pattern similar to that of the thylacine.  Although the duiker and thylacine are not closely related and live on separate continents, the reason for the similarity in their coat patterns is likely due to the fact that they inhabit similar types of habitat, where this particular form of colouration is useful.

    However, the thylacine does show extensive similarities to the Clouded leopard (Neofelis nebulosa) in limb length to body length, as well as to Dasyurus.  This would explain reports made by hunters and trappers of the extreme agility of the thylacine when jumping and climbing.  Despite this, the thylacine is most certainly a ground dweller, as has been demonstrated by many past observations of it in captivity.  Indeed, the thylacine may be most accurately described as a large, ground-adapted dasyurid.