Knob Tailed Geckos are some of the most recognizable and memorable squamates. Although there is substantial variation between the 10 species (wheeleri wheeleri and wheeleri cinctus have been split); a unifying theme is a diminutive “knobbed” tail. All species belong to the genus Nephrurus (pronounced Neff-RU-russ), which means “kidney tail”. All species are restricted to Australia exclusively. As an aside, the genus Underwoodisaurus was monotypic, until the addition of Underwoodisaurus seorsus. In some literature you will find Underwoodisaurus milii included as Nephrurus milii as they were re-classified as Nephrurus from 2007 until 2011, when it was reclassified back as Underwoodisaurus. We will not be discussing either species, instead focusing on “true” Nephrurus.
Smooth Knob Tailed Geckos (Nephrurus levis); De Vis 1886
Nephrurus levis levis;
Nephrurus levis levis; SVL 102mm females larger than males.
Smooth knob tailed geckos are native to arid sandy areas of Central and Western Australia. They are a stout gecko with a smooth skin riddled with small tubercles on their body and limbs. The Tail is large and heart shaped with white tubercles. Each individual is different, and the amount of white varies tremendously (partially due to selective breeding). Generally 3 bands transcend across the base of the head, neck and back.
Reproduction can occur within the first year, females can breed with a weight north of 18 grams, but in my experience a weight of 22 grams is ideal. This can easily be achieved within the first year with proper care. Males traditionally are viable around 15-17 grams..
Nephrurus levis pilbarensis;
Nephrurus levis pilbarensis; differs from the nominate form by a patchwork of large and small granule scales across the throat. The pattern is often more defined with less white.
There are two mutations of this subspecies; albino & patternless. Both mutations are simple recessive. The patternless variety has actually become the most common variant of Nephrurus levis pilbarensis in the U.S. both in normal and albino forms.
This subspecies occupies the territory between the coastal form (occidentalis) and the nominate form.
Nephrurus levis occidentalis;
Found on the central coast of Western Australia. Frequently “speckled” in pattern with a paler over-all coloration and an absence of dorsal pattern.
Pernatty Knob Tailed Gecko (Nephrurus deleani); Harvey 1983
SVL 100 mm, found around Pernatty Lagoon, north of Port Augusta restricted to arid sandy-ridges of South Australia. The tail is very slender, with large white tubercles. The pattern has tremendous variation and no two are alike. Juveniles often have a narrow white vertebral line. IUCN Red Listed as rare. This gecko has the smallest range of the genus and is likely the most at risk in the wild. Females mature at approximately 19 - 20 grams and breed at a moderate rate for the genus.
Starred Knob Tailed Gecko (Nephrurus stellatus); Storr 1968
SVL 90 mm, found in two isolated sand-arid locations vegetated with heath or spinifex. Primary literature puts them north west of Adelaide in South Australia, although they have also been sighted between Kalgoorlie and Perth in Western Australia. This is one of the most colorful Nephrurus species. It is pale yellowish brown to deep reddish brown adorned with three white lines transversing between the head and forelimb. The body and tail are marked with conical tubercles and rosettes. The head is often touched with a blue over the eyes and pastel yellows.
Mid-line Knob Tailed Gecko (Nephrurus vertebralis); Storr 1963
SVL 93 mm. This species has a relatively slender tail with enlarged white tubercles. The body color is reddish brown with a very prominent narrow white vertebral stripe from the base of the head to the tail tip. There are many pale spots each centered on a tubercle.
The natural range is arid with stony soil heavily covered by acacia woodlands, in the arid southern interior of Western Australia.
Females should be 20 grams before being bred. Highly prolific and extremely variable species
Pale Knob Tailed Geckos (Nephrurus laevissimus); Mertens 1958
SVL 93 mm, the Pale Knob Tailed Gecko is nearly identical in build and size to the Mid-line Knob Tail Gecko. The body is nearly devoid of tubercles and pattern, the tail is littered with enlarged white tubercles. The flanks are smooth and only a few tubercles are restricted to the vertebral region. The base coloration is pink to pinkish brown, with or without many small white spots.Three dark brown lines on the head and forebody break the uniformity with the hips marked similarly. This species has a large natural range throughout Northern, Western and Southern Australia in desert sand-ridges vegetated with spinifex.
Banded Knob Tailed Gecko (Nephrurus wheeleri); Loveridge 1932
Nephrurus wheeleri wheeleri; SVL 100 mm, with a large wide depressed tail. This species is covered with rosettes on the body and limbs which protrude from the skin in the form of dense tubercles. The body color is variable; being cream, pink or light brown. The body and tail are trimmed with 4 distinct chocolate bands. Both subspecies are restricted to the arid mid-western interior or Western Australia, inhabiting acacia woodlands in dense stone rich soil.
Nephrurus wheeleri cinctus; this subspecies is what we find in the pet trade. The over-all color and description is quite similar with subtle variation in base color and head structure. The defining difference is that cinctus is trimmed in 5 bands rather than 4. This subspecies is found in rock outcroppings amongst spinifex in the Pilbara region.
Red Line Vs Pink Line
Broad Band Eclipse Eyed
Red Line Vs. Broad Band Red
Hypo Reduced Pattern Vs. Broad Band
Clockwise from bottom left: Red Line, Hypo Reduced, Hypo Broad Band, Broad Band, Reduced.
Pink Line Vs. Red Line
Centralian Knob Tailed Gecko (Nephrurus amyae); Couper & Gregson 1994
SVL 135 mm, the Centralian Knob Tail Gecko has an extremely short tail. This species was named after Amy Couper. The body color varies from a light cream to a rich sandy red, and is adorned with rosettes, the largest and most spinose of which are on the rump and hind limbs. The dramatically large head is trimmed in a beautifully defined reticulation. This is the most massive species of Australian Gecko. N. amyae are native to rock outcroppings of Central Australia.
Northern Knob Tailed Gecko (Nephrurus sheai); Couper 1994.
SVL 120 mm, the Northern Knob Tailed Gecko is very similar to both N. amyae & N. asper. The body is brown with fine dark transverse lines alternating with rows of paler spots, each centered on a tubercle. The limbs and digits are strongly banded. The head has a dark fine reticulum. N. sheai is native to the rocky ranges from the Kimberly region of Western Australia to the Arnhem Escarpment of the Northern Territory.
Prickly Knob Tailed Gecko (Nephrurus asper); Günther 1876.
SVL 115 mm, the Prickly Knob Tailed Gecko formerly included sheai & amyae. It is remarkably similar to N. amyae although somewhat smaller, and often times a rich dark gray color trimmed in subtle paler banding. This species can also be reddish brown and many fine dark transverse lines alternating with rows of paler spots. As with the other two aforementioned species the head is trimmed in a dark reticulum. N. asper is native to the rocky hills and outcroppings of arid to dry tropical Queensland, inland to Windorah.
· Knob Tailed Geckos are incredibly vocal. I have noticed that the “Rough” species tend to be more vocal than the smooth species, although all will make any objection heard. Their amusing “merr merr” noise is the basic limit to their vocal abilities.
· Knob Tailed Geckos wag their tail! Believe it or not that little knob at the end of their tail wags when hunting prey. It is not unusual to place a dubia or cricket in front of a Nephrurus only to watch them track the prey, eyes front fixed, face serious, body moving ever so carefully and cat-like, each foot moving only when necessary…. All the while each granule of anticipation and excitement is visible in the tail tip, pulsating back and forth as fast as geckoly possible!
Husbandry: · We raise hatchlings individually in V-18 Tubs from Vision, on appx 2” of moist sand with a hide box on the warm end. They are fed every other day, and exclusvely crickets. Our adult Nephrurus are housed individually in 32 qt Tubs and custom racks from Freedom Breeder which are based off of a large mouse tray platform.. They are heated via 3" flexwatt "belly heat", or heat cable depending on the rack this is set at 90*F. The cool end ranges between the mid 70's to low 80s. I keep the warm end moist , and the cool just barely moist by pouring water into the sand every few days and churning it. I also spray the entire cage once or twice a week depending on the species. Females eat more and digest faster than males in my experience. I used to rotate between crickets and dubia, but found dubia to be less desirable and eliminated them. Most females will eat 2-5 large crickets every other day and males will eat around half of that. Watch your animals, if you have crickets in the cage the next day remove them and cut back on your feeding. Eggs are incubated in a S.I.M. Chamber from Squamata Concepts, at 82*F with near 100% hatch rates.