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The Gekkonines are the most
successful of the Geckos, with a circumtropical distribution and more than 50 genera. Females characteristically lay two eggs.
The eggs tend to be spherical, and possess a hard, calcareous shell. The shell appears to be an adaptation to prevent water
loss; the eggs also have a higher resistance to decay than the parchment type eggs of Geckos from Dipldactylidae and Eublepharidae. (Goin, Goin & Zug, 1978) North
Eastern India & Bangladesh, Burma, Thailand, Indochina, Southern China, Malaysia, Malaysian Archipelago, Indonesia, Philippines,
Sulu Archipelago and East Australasian Archipelago. (Hermann Seufer 1995) This species
has also been introduced to (www.gekkonids.info) *All of my current collection of aberrant Tokay Geckos have been shipped from This species
is truly adaptable; originally a creature of the forest a noted swing to human habitations has been seen. Tokay Geckos in
It must
be understood however that the Tokay Gecko does not enjoy this level of protection from humans throughout their range. It
is collected in (Zhao & Adler, 1993) When located
in the rainforest during the day they will be hidden in rotten hollow tree limbs of behind loose pieces of bark. Being strictly
nocturnal this would make them almost impossible to find during daylight without a large quantity of luck. To further aid
the blending process many authors list the ability to change shade and depth of colour to blend into surroundings. In houses,
shops and restaurants Tokay Geckos would be located within the rafters, floor boards of meeting floors and in the roof cavity
itself. They actively hunt at night as they hunt insects drawn in by the lights and smell of food and garbage. Tokays have learnt they will not be bothered by humans as they require their extermination powers. As a
result in an evening they will hunt with almost reckless abandon, obviously standing out against the white washed ceilings.
* What has still to be established is where the colour morph Tokay geckos are caught, are
they forest animals or are they human habitation animals. It would make more sense if they were from human habitations through
lack of predation, higher populous within a given area and a sped up birth/reproduction cycle. It could also be the case that
relations who have developed heterozygotic traits are more likely to subsequently reproduce and therefore expose a homozygotic
colour change than in the forest where their camouflage would be seriously diminished increasing their chances of predation.
It has also been suggested although with no evidence to corroborate that the colour morphs Tokays may be separate sub-species
or totally separate species. This I feel seems unfounded and although mentioned here merely out of interest I would disregard
it until evidence/ research is forth-coming. This is
the largest member of the Gekko family with an overall adult size of 280mm-340mm. Females are smaller at around 220-270mm.
They are powerfully built animals with very agile and muscular legs, a well defined and immensely powerful head and jaw and
undivided toes lined with lamellae. The tail is thick set and not obviously prehensile, possibly due to the incredible efficiency
of the feet. The tail like the body but to a greater degree is covered with conical
protrusions. The conical protrusions are larger either side of the cloacal opening, being larger in males (although this could
simply be attributed to the overall larger size of the male.) Colouration of normal –wild type Tokays is highly variable dependant upon time of day captured and location captured. Most normal Tokays
in the pet trade have a base colour ranging from dark blue, light blue, grey to almost silver to almost black. Various pale
brown, orange through to red dots appear on the body as well as slightly lighter blue small dots inter-dispersed apparently
randomly. Like many geckos Tokays go through an ontogenetic change from being neatly banded to randomly dotted (not dissimilar
to Leopard Geckos – Eublepharis Macularius). The previously mentioned random light blue dots play a part in the original
banding helping to break up the darker base colour of neonates.
Powder
blue is by far one of the most popular of the colour morphs it is also one of the most common. The base colour is a light
blue with the tips of the tubercular scales being lighter still. There is no pattern to speak of. Eyes are golden with brown
veins. Throat is pigmented. Belly has a slightly more yellow blue appearance than the trunk. When cool/unexcited colours are
far darker almost approaching dark grey, tubercular scales still have a lighter hue in this state.
Blue
headed green is another relatively common colour morphs of Tokay. The base colour of the head is the same as for powder blue
yet at the collar the colour changes to a pastel green. Tubercular scales on trunk are the same colour as the head. There
is no pattern to speak of. Eyes are golden with brown veins. Throat is pigmented. Belly has a more yellow hue and this yellow
is stronger than seen in the belly of Powder Blues. When cool/unexcited colours are very dark green and on occasion almost
black, tubercular scales still show lighter hues even when in this state.
Blue
Granite is just a name the author has given this male and it seems to fit. The base colour is a light-ish blue green with
lighter blue cross bars including intersected tubercular scales. Speckling on the head is lighter than the body being an almost
grey purple. These speckles and dots seem to have a golden outline which is most fetching. On the trunk the colours present
in varying degrees are hues of light blue, green/blue and yellows. The largest spots seem to be arranged in loose rows with
smaller dots loosely around them. The largest spots centre on tubercular scales but spread out past the base of the scale
where it meets the rest of the trunk skin. Legs take on a more greenish/yellow hue and the belly is still blue. Eyes are Grey/blue
with darker veins, pupil has a light blue/white outline. The throat is pigmented. When cool/unexcited most traces of blue
are lost and the overall colour is grey with black blotches, the tail is also black. Unlike the two previously mentioned morphs
instead of the tubercular trunk scales being lighter than the body on Blue Granites they are much darker.
In the authors personal opinion the Blue & Green/Yellow Granite is one of the
most attractive geckoes he has ever seen. This is the name that this morph arrived with although the author has some doubt
as to whether it is indeed granite as granites seem to have darker and on occasion black spots which this morph is totally
devoid of. Base colour is either green or yellow dependant upon mood and time of day. Feet are always yellow with blue dots.
On the trunk blue saddles are prominent which are edged by turquoise dots. The
head pattern is paler with a more blue overall hue. The belly is green/yellow with sporadic blue speckling. Eyes are gold
with brown veins. The throat lacks pigment. When cool/unexcited the overall colour is much darker with no sign of the beauty
beneath.
This
female was bought as a granite but is totally different to the blue granite male. The head base colour is blue with orange
dots lines with a deep lichen green. The body base colour however is grey through to lichen green dependant upon mood/temperature.
Tubercular scales on the body are either coloured a rusty orange or light blue, making the pattern of this granite female
particularly busy. The belly is blue with sporadic orange speckles. Eyes are gold with brown veins. The throat is pigmented.
When cool/unexcited this lizard is very drab with none of the mixtures of colour mentioned above.
Either termed blue calico or blue granite calico either
way this female is very interesting. This female was bought as a standard calico but from the picture it becomes rather obvious
she is not. Head markings are standard for calicos in that she has an apricot head, but that is where the similarity ends.
The body is a deep blue with lighter watercolour wash of light blue. Sporadic very small orange spots are present. Belly is
blue with small orange freckles. Eyes are black with some silvery/white detail, pupil is black. Throat lacks pigment. Cool/unexcited
colours are very drab, the full body goes very dark grey almost approaching black. The unexcited colours were retained up
until a few weeks ago after a period of some three months settling in period. It is quite clear that
I have two different types of Calico, what may well be the case is the resounding differences surrounding the two normal Calicos.
The one pictured is the female. Each calico obviously has differing amounts of pigmentation as pigmentation is lost through
time and there is discussion suggesting that most calicos will become leucistics if given enough time. The author has seen
young adult leucistics though and that seems strange if the process is solely a time thing or again whether there are two
differing types. There seems little point in discussing patternation due to variablility apart from the fact that calicos
usually have an apricot head, black eyes with silver veining and varying black grey patches.
Hypomelanistic Tokay Geckos usually arrive graded A,B,C. A being the best coloured. The female pictured is an A grade
Hypo, where as the male came in as a C grade. The difference is marked and whilst it is apparent the male is not normal, I’m
not sure he is a hypo either. Description on such a sliding scale is difficult. The female in my possession has a lilac head
with vivid orange spots, the body however has a pastel lavender base colour and the orange dots loose the intensity seen on
the head. Occasional lighter blue flecks appear and seem to congregate down the centre of the dorsal area. The eyes are gold
with light brown veining. The throat in the female lacks pigments whilst the male has pigment.
This is
the authors opinion is one of the most interesting morphs here whilst not necessarily being the most eyes catching. The Patternless
Axanthic was sold to the author as a C grade Axanthic but it has become quite apparent she is any thing but! The body has
grey/brown flecks which look to be receding leaving an apricot/white colour. The body looks to have blushing from the belly
half way up the flanks. The dorsal colour is a very faded light brown wash, the lower flanks and belly colour is porcelain
white. The legs and feet are also white. The eyes are black and the throat lacks pigment. This could well be either a Patternless
calico or an Axanthic calico, but time will tell to see if the white spreads further.
Most lizards
can detect airborne sounds, but only the nocturnal geckos from the subfamily Gekkoninae regularly use acoustic signals for
communication. Geckos are unique in the lizard world in that they have vocal cords and as such can produce more complex sounds
than hisses and gasps. (Marcellini, 1977) Males
vocalise a territory and these are termed multi-chirp calls. These calls can be directed at specific males or females but
are also given spontaneously as well. Sub-ordinate males move away from recordings of multi-chirp calls yet no response was
elicited from females (the reproductive state of the females in question was not ascertained so the experiment does not necessarily
show that the calls are not attractive to females. It is assumed that in fact they are.) (Pough, 2001) Vocalisations
given during aggressive interactions are called churr calls. These consist of longer notes than those discussed in multichirp
calls. This call is seen in altercations between conspecific males (one of which no doubt either ignored a multi-chirp call
or was unnaturally enclosed in captivity with a male of assumed equal prowess in the vivarium – the latter being the
most likely.) and humans or other perceived predators. (Marcellini, 1977) Tokay
Geckos particularly have a very complex vocal repertoire. This species is unique in having a multipart advertisement call
that begins with a rattling sound that is followed by a series of two-syllable chirps. Nothing is known about the significance
of these call components, but it is possible that Tokays resemble some frogs in using part of the call to fend off males yet
with another part to attract females. (Brillet & Paillette, 1991) *A difference noticed by the author between the sexes of the Tokays is the depth of the
croak. What is discussed in text read in numerous places if the frequencies utilised by Tokay Geckos but no mention is made
of the use of lower frequencies by males and conversely higher frequencies by females. The adult males that are in the collection
have a much more powerful gruff deep voice where the females are more likely to squeak by comparison. I conclude that depth
of voice may play a role in sex determination of Tokay Geckos. Although it must be noted that this has not been scientifically
proven and is only the authors opinion.
Pre-cloacal glands, the femoral pores or to be more precise inguinal pores were first described by Linnaeus (1758)
(Funny that the Tokay was found and described the same year! – Could the two
be connected). They are epidermal structures present in many lizards. Pre-cloacal glands and femoral pores when considered in comparative anatomy are said to be homologous (features that
may have the same evolutionary origin but not necessarily the same function. - D.C.Wareham,
2005.) (Gabe and Saint Girons, 1965) The glands produce copious amounts of holocrine secretion as a solid core and appear mostly in males. The pores are
invariably larger in males. The amount of secretion produced in different seasons has never been measured quantatively, but
it is generally accepted that femoral glands secrete more actively in the breeding season. (Gans & Crews,1992) * Much text found about Tokay Geckos says how easy it is to sex this
species due to the male having pre-cloacal pores, what the various texts fail to mention is that the females also have them.
When considering Leopard Geckos (Eublepharis Macularius) males have hollow pores which are visible and males are determined
by their presence regardless of whether holocrine plugs are present or not. Females look to almost have vestigial marks on
the scales but seem to lack the capability to exude holocrine plugs from them. This is not I have discovered the case in Tokay
Geckos. Females too have hollow pre-cloacal pores although no plugs have been found to be present in any of the females. In
the males the pores are only slightly bigger yet they do have holocrine plugs present. I conclude that by using
these pores alone it may not be totally reliable to sex them unless you are fortunate to have number present for comparison.
The use of these pores in conjunction with other variables used to distinguish sex may still be useful. Other variable will
be discussed later. These
glands lie above a ductus endolymphaticus and are connected to the static organ. The calcium sacs lie in the lower throat
and usually contain a milky calcium carbonate liquid. It is increasingly thought that the calcified endolymphatic sacs serve
as calcium reserves enabling the female to produce hard shelled eggs. In favour of this theory is the fact that amongst Gekkonidae
they are only found in Sphaerodactylinae and Gekkoninae, and that they are absent in Diplodactinae and Eublepharinae, which
lay soft shelled, parchment like eggs. Against the theory however that is in some species that males also have endolymphatic
sacs which do not contain calcium. This storage system prevents the female suffering enormous “calcium stress”
whilst gravid, and simultaneously guarantees that sufficient calcium is available during the relatively short period in which
the eggs are formed. There is even calcium in the endolymphatic sacs of embryos
and newly hatched young. This calcium is vital to strengthen the skeletal bones of the young. (Henkel & Schmidt, 1995) The Gecko’s ability to
scuttle up vertical walls and even run around upside down on a ceiling was once the source of much controversy among naturalists.
Some said that the rows of plates on the underside of the feet secreted some kind of glue – but no trace of it could
be found. Others maintained that the pads created a suction. That suggestion was disproved by putting the animals on a pane
of well-polished glass on which suction should work particularly well. But the animals could not maintain their foot hold
at all well. Eventually, electron micrographs of the pads revealed that each carries literally millions of tiny hairs. Each
of these splays out at its end into twenty or so spatulae that are so infinitesimally small that they are able to utilize
that force that binds molecules together (Van Der Waals force). This force only operates between bodies that can get within
molecular distances of one another, but the hairs, being so extremely small, can indeed do this. The tiny setae (microscopic
spatulae) which produce an immense amount of grip when on an optimum surface (130kgs). The strong adhesion is aided by a force
known as Van der Waals Force which draws molecules together (the molecules of the climbed surface and those of the foot) disengagement
occurs at an angle of 30 degrees and this is achieved by curling or rotating the foot. (Attenborough, 2008)
From reading various texts on Tokay Geckos it becomes apparent how many people list the colour changing capabilities
of Tokays. What is usually said is that they are nice and bright in the vivarium but when handled darken down considerably.
I have found the total opposite and this could be just to do with the colour morph Tokays. All of the colour morphs except
the high whites (Calico and Patternless Axanthic) brighten up when handled. To complete the colour change usually takes from
3-4 minutes. Warwick, Frye and Murphy discuss what is called ‘emotional fever’ where an animal can raise its core
body temperature by 6 degrees during times of handling stress. Could the increase of temperature play a part in the colour
change? It seems strange to me that this colour change takes place in only my lizards at not normals, as the colour phases
which change up rather than down when handled have melanin same as a normal and one would expect the colour change to follow
suit. When ‘free’ handling a Chameleon for example it is quite common for the brightest colours to be exhibited
as the animal using colour communication wishes to exert some form of dominance. Once the chameleon has been forcibly restrained
the colour deepens to black. Now as most Tokay Gecko keepers know if you have a run of the mill wild Tokay Gecko you will
be restraining it or it will be hung of your finger end! Yet the colour stays bright – is this because of the Tokay
Geckos never say “die” attitude? |
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