Herpetology Notes, volume 11: 777-779 (2018) (published online on 06 September 2018)

Triplet from a single egg in the Panther ( pardalis)

Falk Sebastian Eckhardt1,*

Among oviparous , twinning has been reported and died after 20 days. From the residual nine eggs, for several taxa: chelonians (Lehmann, 1984; Cohen, hatchlings were noted protruding from all but one 1986; Eckert, 1990; Stumpel, 2007), crocodilians (Platt egg between the 6th and 9th of December (8 months et al., 2001), and squamates (Curtis, 1950; Carpenter of incubation). However, the remaining egg showed and Yoshida, 1967; Marion, 1980; Kinkaid, 1996; slashes in the shell, but no hatchling emerged for three Wallach, 2007). However, the appearance of a triplet days (until the 9th of December). After having been from a single egg has only been reported by Krauss manually opened, the egg contained two live hatchlings and Horn (2004) for the Lace Monitor Varanus varius and one dead, malformed offspring (see Fig. 1). The (White 1790). I hereby report an instance of a triplet malformed embryo had clearly died some days before in the Panther Chameleon Furcifer pardalis (Cuvier the egg was opened as the skin had begun to deteriorate. 1829). Remarkably, the malformed embryo did not exhibit Both parents were captive bred and unrelated functional eyes or a mouth (Fig. 2). The two living specimens from the colour, - or local morph individuals were smaller (SVL) and lighter (2.2 cm, “Ambilobe” (e.g. in Müller and Lutzmann, 2016). The 0.2 g and 2.3 cm, 0.2 g respectively) than the remaining male was approximately one year of age. The female siblings from the same clutch (n = 8, 3.03 ± 0.05 cm; 0.69 was approximately two years of age and copulated for ± 0.04 g; mean ± SD). Both were kept together and were the first time. After the first observed mating on the separated from their bigger siblings in one enclosure. 19th of March in 2017, were separated due to Food (Drosophila, micro crickets) were offered and the subsequent aggressive behaviour of the female. water was provided by spraying daily. Both were Hereafter, the female produced one clutch deposited on the 7th of April (19 days after mating) containing 24 eggs. This clutch showed 14 eggs that were notably smaller and started to mould after several days. The remaining 10 eggs showed normal development and were equally sized. They were incubated at 26°C for 75 days, followed by a cooler period of 23°C for 60 days and then 26°C until the last hatchling emerged. Incubation took place on vermiculite in an incubator of the model “Lucky Herp Nursery II”. The first hatchling appeared on the 6th of November (7 months of incubation), showed relatively lethargic behaviour

1 Abteilung Soziobiologie/Anthropologie, Institut für Zoologie und Anthropologie, Universität Göttingen, Kellnerweg 6, 37077 Göttingen, Deutschland Figure 1. Triplet of F. pardalis. The specimen in the middle is * Corresponding author. E-mail: [email protected] the malformed individual. 778 Falk Sebastian Eckhardt

small temperature gradient in the incubator might have possibly accelerated the development and lead to the early hatching of this specimen. This is supported by the fact that this egg had a slight outer position in the box. Moreover, the first clutch, resulting relatively fast after mating, contained only 41.7% of fertilized eggs whereas the second one, which was fertilized by sperm that was stored for several weeks, contained 100% fertilized eggs. This clutch containing 28 eggs showed a rate of 100% hatching of agile juveniles with an average SVL of 2.95 ± 0.06 cm, and weight of 0.69 ± 0.04 g.

Acknowledgements. I thank Philip-Sebastian Gehring and Claas Wegner from the University of Bielefeld for offering the male Figure 2. Detailed view of the head of the malformed specimen. Panther Chameleon for breeding with my female. Moreover, I Neither outer eyes nor a functional mouth is identifiable. thank the referee Anthony Herrel for helpful comments on this paper.

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Accepted by Werner Conradie