The smallest species often are hidden among the mosses in a sphagnum bog.
The world's smallest species of goanna, measuring just 23cm and weighing 16g, was found in December, while several new geckos have also recently been unearthed.
The smallest species, Denise's pygmy sea horse (H. denise), is found in the tropical western Pacific from Indonesia to Vanuatu.
The adults of the smallest species are about 2 cm (about 0.8 inch) long, the largest about 200 cm (about 79 inches).
In comparison, the smallest species, the smooth-fronted caiman (Paleosuchus) and the dwarf crocodile (Osteolaemus tetraspis), reach about 1.7 metres (about 6 feet) in length as adults.
The minimum time from hatching to first reproduction appears to be about 10 to 15 years, a characteristic shared by the largest species, D. coriacea, and the smallest species, L. kempii and L. olivacea.
Bamboo culms can attain heights ranging from 10 to 15 cm (about 4 to 6 inches) in the smallest species to more than 40 metres (about 130 feet) in the largest.
The largest species, Caecilia thompsoni, reaches a length of 1.5 metres (5 feet), whereas the smallest species, Idiocranium russeli, is only 90 to 114 mm (3.5 to 5 inches) long.
The smallest species (N. pygmaeus), restricted to forests east of the Mekong River, is about 25 cm long; the larger N. coucang and its relatives, widespread in Southeast Asia, are about 27 37 cm long.
One of the smallest species is a South American fish-eating rat (Neusticomys monticolus) with a body length of 10 to 12 cm (4 to nearly 5 inches) and a tail of about the same length.
The campaigners, who are to present their findings this week to the annual meeting of the international body on endangered species, warn that the vaquita, whose name translates as "little cow" and is the world's smallest species of cetacean, faces a particularly dire future with as few as 97 of the mammals left.
