Added 15 June 2000: last updated 27 January 2001 with thumbnail images.
The axolotl is a completely aquatic species that never loses its larval gills during the normal course of its life. Originally the species' habitat was confined to two lakes in Mexico, but these have been so reduced that little is known of the wild population. Virtually all axolotls offered now have been bred in captivity, having been kept in homes and laboratories for years around the world. They make fairly hardy captives that require a simple tank of cold water, although shelters are advisable if more than a pair are to be kept. They are good eaters. The natural colour of these creatures is brown, but breeding over the generations has produced plenty of the leucistic (white) examples, plus other colours. Perhaps the only drawback to keeping axolotls is that their size (about 12") necessitates a larger tank of water with the attendant demands of filtration, cleaning, etc. A pair of axolotls will breed readily.
Taricha torosa is a fairly hardy newt that grows to about 7", with a brown back and tan yellow underside. It is somewhat flattened in appearance. The reason that it is included in this section as opposed to Level 1 is that (a) it is often overcollected (b) it is under other pressures in the wild, such as loss of habitat (c) it requires a cooling period during the winter, not just for breeding purposes but also for general health (Indiviglio).
Members of the Triturus genus are found in much of Europe, including the British Isles. They favour cool water and apparently need more optimal care than, for example, the Eastern Newt of North America. The aquatic phase lasts from spring to early summer, after which the newts become terrestrial until the winter hibernation period. A period of dormancy seems to be a prerequisite for successful breeding. Care should be taken handling these newts as their skin is very toxic. For these reasons, plus the fact that Triturus species are restricted or protected in some parts of their range, I would consider this to be a Level 2 animal rather than a starter species.
Much of what has been said about the Crested Newt applies to the Marbled Newt. This may be considered somewhat easier from a size point of view, however, as they rarely grow longer than 6". They are very attractively patterned. Apart from a brief aquatic breeding phase they are terrestrial. Indiviglio recommends winter cooling and in addition shortening the photoperiod during this time to simulate their seasons in the wild. Like the other Triturus species they are very sensitive to water quality.
This is the largest European newt at 12", and thus requires a somewhat larger tank than most other newts. The rows of warts along its sides are actually protrusions caused by its ribs, hence the name. Despite its size it does require a hiding place and does not become as tame as some other newts. Indiviglio recommends shallow water thickly planted with devil's ivy, with a shelter provided by a clay flowerpot or piece of bark. This newt is almost entirely aquatic.
Attractive plethodontid salamander instantly recognisable by its green coloration, the Green Salamander is also known as the "climbing" or "tree" salamander owing to its arboreal abilities, although its inclination is rather to climb into crevices to avoid predators and dessication (Indiviglio). It is not large (3-5") but requires a very moist environment with rock crevices to shelter in (ie some sort of narrow cave-type shelter) in addition to the usual moss, and a secure top on the tank. Small food items are a must. Eggs are laid on land and hatch out terrestrial salamanders, thus avoiding the aquatic stage entirely.
The sirens are an unusual family of salamanders from North America who are so distinct that some have considered placing them in their own order (Indiviglio). Although the other two members of the family are quite large (up to 2ft long), the dwarf siren is much smaller (up to 8½" or less) and had fairly modest requirements. Indiviglio recommends clean, shallow water with plenty of cover, ideally the water hyacinth (genus Eichhornia) if possible but otherwise devil's ivy as a good substitute. There is still much that we do not know about sirens, particularly their mating habits and method of egg fertilisation, so here is an opportunity for the amateur herpetologist to contribute towards scientific knowledge.