The following are the dragons found in the Harry Potter universe. They are found either in the Harry Potter books or in the spin-off book Fantastic Beasts and Where to Find Them.

Asian Dragons

Antipodean Opaleye

The Antipodean Opaleye dragon is native to New Zealand although it occasionally appears in Australia. Unlike other dragons, it prefers valleys to mountains. Its appearance is very beautiful due to its pearly scales and glittering eyes. Its flame is a striking scarlet. A shy dragon, it will not attack humans unless it is incredibly hungry. The Antipodean Opaleye normally eats sheep although it will sometimes attack larger prey. This dragon's eggs are a pale grey and may be confused with fossils.

Chinese Fireball

Also known as Liondragon, the Chinese Fireball dragon is the only mainland Asian dragon. Its scales are scarlet and smooth, golden spikes outline its face, and has protruding eyes. It weighs in at two to four tons. The Chinese Fireball is known for being much more tolerant of its own species than other dragons usually are. Its gold-speckled egg shells are prized in Chinese wizardry.

British Dragons

Common Welsh Green

The Common Welsh Green Dragon is found almost exclusively on a reservation in Wales where preys on sheep. This dragon avoids humans. It has a melodious roar. Fire is spewed from its nose in thin jets. Its eggs are brown with green specks.

In 1932, a Welsh Green flew over a beach of sunbathing muggles. Fatalities were prevented because of the efforts of a wizarding family that happened to be on holiday there at the time. These wizards performed one of the biggest batches of memory charms in a century on the terrified muggles, thus upholding Clause 73 of the International Code of Wizarding Secrecy (which states that if any magical creature is notice by muggles in a particular country, that country will be subject to discipline by the International Confederation of Wizards.) However, according to the 1972 book by Blenheim Stalk, there is one muggle who escaped the memory charms. To quote from his book, "To this day, a Muggle bearing the nickname 'Dodgy Dirk' holds forth in bars along the south coast on the subject of a 'dirty great flying lizard' that punctured his lilo."

Hebridean Black

More aggressive than its Welsh counterpart, the Hebridean Black dragon is a large and fiercely territorial species. Requiring up to 100 square miles per dragon, this species is a threat to all manner of creatures ranging from deer to cattle. The dragon is up to thirty feet long and and has razor-sharp ridges on its back. The wizard clan MacFusty has traditionally taken care of the dragon.

Eastern European & Scandinavian Dragons

Hungarian Horntail

The most dangerous of all dragons, the Hungarian Horntail has black scales and is lizard-like in appearance. It's eyes are yellow and it has bronze horns. Its fire can reach up to fifty feet. This dragon feeds of of large mammals, and enjoys eating humans.

Norwegian Ridgeback

The Norwegian Ridgeback happens to be one of the two species of dragon that Harry Potter has encountered during his years at Hogwarts. The book "Fantastic Beasts and Where to Find Them" notes several facts about this species, including the ridges on its back (hence the name), the fact that the species preys on water-dwelling creatures, which is unusual for dragons ( probably because fire and water don't mix), and the fact that this particular species develops its fire-breathing abilities at the age of 1 to 3 months, which is earlier than other species of dragon.

Romanian Longhorn

The Romanian Longhorn dragon has dark green scales and long, golden horns. The species' traditional breeding ground is now a major dragon reservation for all breeds. The Romanian Longhorn is endangered and is the focus of an intense breeding programme.

Swedish Short-Snout

The Swedish Short-Snout dragon is a silvery-blue dragon whose skin is used for the creation of protective gloves. Its flame is the same colour as its skin. This dragon has killed fewer humans than most, largely because it lives in uninhabited areas.

Ukrainian Ironbelly

The Ukranian Ironbelly is a large and slow dragon, but is still very dangerous. One of the most common risks associated with the dragon is its ability to land on dwellings and crush them. Its skin is a metallic grey, its eyes a deep red, and its talons are long. In 1799, it picked up an entire sailing boat from the Black Sea.

American Dragons

Peruvian Vipertooth

The Peruvian Vipertooth is a small and swift dragon with coppor-coloured skin. The dragon has short horns and venomous fangs. It enjoys preying on humans to the point that the Ministry of Magic had to send exterminators once in order to reduce the threat to the human population.

Sources

Fantastic Beasts and Where to Find Them