Crocodile skinks squeak, guard their eggs, and lay one egg at a time — behaviours almost no other lizard in the hobby shows. They look like miniature dinosaurs and they behave like nothing else on the shelf.
Quick answer
- Small: adults are roughly 6–8 inches total length.
- Humid and cool-ish — around 75–82°F with high humidity and a water dish they can get into.
- Deep leaf litter and heavy cover. A bare enclosure makes them invisible and stressed.
- They vocalise — a high-pitched squeak when alarmed, which is rare among lizards.
- Females lay a single egg per clutch and have been observed guarding it.
- Display animals, not handling animals.
The two species you will actually meet
The genus Tribolonotus holds eight species from New Guinea and the Solomon Islands, but only two appear in the trade with any regularity: T. gracilis, the red-eyed crocodile skink, with its bright orange-red eye rings, and T. novaeguineae, the casque-headed skink, which lacks the eye rings and has a more pronounced head shield. Both were described by the Dutch herpetologist Nelly de Rooij in the early twentieth century.
Care is broadly the same for both. The difference that matters commercially is availability: red-eyed animals are established in captivity far more widely, so provenance is easier to establish for them than for their relatives.
The build
| Element | Detail |
|---|---|
| Enclosure | 18×18×12 inches for an adult or a single pair. Floor space matters more than height |
| Substrate | Deep, moisture-holding bioactive mix with a thick layer of leaf litter over it |
| Humidity | High and steady — they come from humid forest floor near water |
| Temperature | Roughly 75–82°F. No harsh basking lamp |
| Water | A dish large enough to sit in. They swim, and they use it |
| Cover | Cork flats, leaf litter and live plants. More hides than you think you need |
| Diet | Small insects — crickets, small roaches, worms — dusted with calcium |
| Housing | Alone or as a single pair. Never two males |
A clean-up crew genuinely earns its place here: springtails and isopods keep a permanently damp, litter-heavy enclosure from going sour. Rubber Ducky isopods are a display species rather than a workhorse, so for this job pair them with something faster-breeding — types of isopods covers which does what.
The behaviour that makes them worth keeping
They squeak. A distressed crocodile skink emits a sharp, high-pitched call — genuinely unusual in lizards, and the first thing that surprises new keepers. They may also freeze completely or go limp when handled, which looks alarming and is a defence rather than a health problem.
They parent. Females lay a single egg rather than a clutch, repeatedly through a season, and have been observed staying with and guarding it. Reproductive investment on that scale is why they are never abundant and never cheap, and it is the same economics that makes live-bearers expensive — see do lizards lay eggs.
What people get wrong
Two failures account for most losses. The first is letting the enclosure dry out: these are wet-forest animals and chronic dryness causes failed sheds and decline. The second is too little cover, which produces an animal that hides permanently, refuses food and is assumed to be ill when it is simply exposed.
They are also crepuscular, so an animal you never see at midday is behaving normally. Judge health by weight and feeding response, not by visibility.
The wider range is under lizards for sale, and everything ships under our live arrival guarantee.
For the same tropical-humid instincts at a very different scale, see sailfin dragons; for the exact opposite requirement — hot, arid and terrestrial — see knob-tailed geckos.
Common questions
Do crocodile skinks make noise?
Yes. They produce a high-pitched squeak when alarmed, which is rare among lizards and is one of the species’ most distinctive traits.
How many eggs do crocodile skinks lay?
One at a time. Females lay a single egg per clutch, repeatedly through a season, and have been observed guarding it — parental care is unusual in skinks.
Can crocodile skinks be handled?
They tolerate it poorly. They may freeze, go limp or squeak. Treat them as a display species and interact through feeding and observation instead.
What is the difference between red-eyed and white-eyed crocodile skinks?
Tribolonotus gracilis has the bright orange-red eye rings; T. novaeguineae, the casque-headed skink, lacks them and has a more pronounced head shield. Husbandry is broadly the same.
Do crocodile skinks need water to swim in?
They should have a dish large enough to sit in. They come from humid forest floor near streams, they are capable swimmers, and they use standing water readily.