All our adult breeding Eastern Casqueheads are female and reproduce parthenogenetically (without the participation of a male), and with a 100% hatch success rate.
L. longipes are one of a very small group of animals that are capable of facultative parthenogenetic reproduction. This is a selective method of reproduction by a female without the need of a male. It is a very (very) complex subject. A quick search of the Interweb will provide plenty of detailed scientific explanations of how it works, but here is a very simple non scientific description based on how we understand it.
In the more common method of reproduction involving a male-female interaction, the female produces egg cells containing her chromosomes in a process known as meiosis, and as a by-product she produces secondary cells called polar bodies. These polar bodies also contain copies of her chromosomes and are normally rejected later after the egg cells have been fertilised by a male. During mating a male will provide sperm cells containing his chromosomes. An egg cell and sperm cell meet and they merge, a bit of genetic and chromosome rearrangement takes place leaving the correct number of chromosomes so that a viable embryo develops, and life begins.
In parthenogenetic reproduction there is no male interaction. There are several known methods for how this can happen in nature, but the most likely process in L. longipes is called automixis. This is where a hormonal change in the female allows her normally rejected polar bodies to take the place of sperm cells and merge with her egg cells. The same genetic and chromosome rearrangement takes place to leave the correct number of chromosomes so that a viable embryo develops, and again, life begins. Because the embryos only have her chromosomes and genes these parthenogenetically produced offspring can be considered clones of the mother, although biologically they are not as the slight reorganisation of the mothers' genes caused by the merger means that some genetic mutation can still occur.
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Females who have reproduced parthenogenetically can still reproduce by mating with a male if one becomes available as it is a selective (facultative) process in L longipes. Whilst this process has been reported in a growing number of reptile species in captivity it appears to be unclear just how common it is in wild populations.
All our adults are females and all have produced viable clutches of eggs without male participation and with a 100% hatch success rate, so the process clearly works. We found that when our females were housed individually they never became gravid, but when housed in pairs both females would become gravid and produce viable eggs, and do so within a few days of each other. This would suggest that when females are ready to breed, without an available male it needs the presence of at least two females together to trigger the hormonal changes that cause the parthenogenetic reproductive response, and that they trigger it in each other at about the same time.
It is very obvious when a female becomes gravid. Her markings become stronger and brown cross bands develop over her back. She will appear to gain weight and the eggs will soon be seen as bulges in her flanks. Once gravid they need the environmental conditions to be just right before they lay. Within a few weeks she will be seen spending more time on the ground and will start digging test holes in the damp substrate looking for a suitable lay site. As no physical mating takes place in our L. longipes it is difficult to say exactly how long the gravid period lasts, but best we can estimate from observation is around 3 to 4 weeks from becoming visibly gravid to laying. We do not separate gravid females as the other tank mates will ignore her change in behaviour and we feel it is therefore less stressful for her to stay in an environment she knows.
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She ideally needs at least 6 - 8cm of loose warm damp substrate before she lays. Sometimes she will lay in the first hole she digs, other times she may dig many holes over several days before deciding where to lay. The temperature and moisture content of the ground are critical, so she will use these test holes to find the best site. When she does lay her eggs it is normally as deep as she can get them, and she will fill in the hole perfectly after laying to hide their location. We keep a note of where she is digging as her sudden thinner appearance is often the only indication that she has finally laid. Ours typically lay 5 or 6 eggs in a clutch and will lay up to 3 clutches in a season that starts around mid May, with each clutch about 4 - 5 weeks apart. The eggs measure about 20mm x 10mm and can be anything from a light beige colour through to pure white. After laying the new mother usually recovers very quickly.
As soon as they are laid we remove the eggs from the vivarium and mark the tops with a marker pen so that they don't get turned. We incubate the clutches in 3 litre plastic tubs that contain a 50:50 mixture of damp vermiculite with either Hatchrite or Superhatch, at about 28°c (82°f). At this temperature they usually hatch at around 50 – 54 days, although it has been as short as 40 days or as long as 60 days and all survived. We do not measure the humidity in the incubation tubs, just check them every few days to keep the hatching medium damp, allow a fresh air exchange, and wipe off any condensation from the inside of the lids to prevent the eggs getting dripped on. At around 48 hours before hatching fine droplets will start forming on the outside of the eggs, a clear indicator that hatching is imminent.
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Once it pips the baby is usually out of the egg and running around within a few hours. We have not had any issues with babies getting stuck in an egg or needing help hatching, they all manage unaided. Hatchlings are around 3cm long nose to vent or 12cm including the long tail when they emerge from their egg, with very little size variation across the clutch, and look identical to the adults.
As each egg hatches we leave the babies in the incubation tub for 12 – 24 hours while the umbilicus heals before transferring them to a vivarium that is set up exactly the same as for the parents only smaller, typically around L60cm x W45cm x H45cm. Initially the entire clutch goes in together but as they grow the babies get moved into larger vivariums or split up. Although the babies can be very lively and active during the day we have never had any problems with aggression or arguments between them. In fact they like to stick together, often climbing over each other during the day. They then huddle down in the leaves as one big group at night to sleep. The babies are fed daily on small Locusts, Crickets and Buffalo Worms dusted with the usual proprietary supplements, and are sprayed down several times a day. They can usually be sexed after about 6 months, reaching full size and sexual maturity at around 18 to 24 months old.
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