Day gecko (Phelsuma antanosy)

Also known as: Antanosy day gecko
KingdomAnimalia
PhylumChordata
ClassReptilia
OrderSquamata
FamilyGekkonidae
GenusPhelsuma (1)
SizeSnout-vent length: 3.3 - 4.8 cm (2)

Listed as Critically Endangered (CR) on the IUCN Red List (1) and listed on Appendix II of CITES (3).

A Critically Endangered reptile, the day gecko is found only in tiny forest fragments in southeastern Madagascar (1). An otherwise vibrantly green gecko, three red lines sit conspicuously on the rear of the back and two distinctive red bars, that are surrounded by a scattering of blue spots, run between the brown eyes and yellow eye-rings (2). The throat, belly and underside of the tail are all a contrasting white (4). In common with other geckos, the body is flattened and soft skinned, with a large head that lacks eyelids; the day gecko instead using its long, mobile tongue to clean its eyes (5).

The day gecko is known from only the Ambatotsirongorongo Forest and Sainte Luce in the Tolagnaro region of southeastern Madagascar (1) (4). The distribution of this island endemic is highly fragmented and it was once also found in the Petriky Forest, but has not been seen there since 1994 and is now thought to be locally extinct (1). 

The day gecko has a very close association with a single species of Pandus tree in which it lays its eggs, and it is only found in the coastal forests of the Tolagnaro region that support this tree species (1). 

As its common name suggests, the day gecko is a diurnal species that locates its prey using a combination of visual and chemical cues. Insects, spiders and other small invertebrates are its main prey, but the day gecko will supplement its diet with fruit, pollen and nectar from flowers (5). The day gecko has also been observed forming an unlikely symbiotic relationship with plant hopper insects. The gecko repeatedly nods its head at the insect until it receives a ball of honeydew, a sugar-rich substance secreted by the insect upon which the gecko feeds. This relationship is not entirely understood; however, it is possible that the insect receives protection from predators in return for its secretions (6). 

Geckos have well-developed vocal cords and, consequently, are capable of producing a large variety of chirps, clicks, growls and barks, which along with visual signals are used in communication. Most gecko species produce two hard eggs, which may be laid in shallow pits, under bark or on plant or rocky surfaces (5).

Occupying an area thought to be no more than nine square kilometres, the day gecko is threatened by further loss of its habitat. This extremely rare gecko has a highly fragmented distribution, making it vulnerable to any detrimental activities within what little habitat remains (1). One small population is likely to be lost within the next 25 years as mining activity is planned in part of Sainte Luce, while many other populations are under continual threat from local communities exploiting the forest’s resources (1). Indeed, the day gecko is suspected to have become extinct in Petriky Forest due to tree felling for timber, fuel and conversion to agricultural land (2). This highly specialised species is also threatened by the selective removal of Pandus trees (1). 

The Ambatotsirongorongo Forest, which supports a large proportion of the remaining day gecko population, is encompassed by a newly created protected area. Five forest fragments at Sainte Luce in which the day gecko is also found are also managed within a community resource use agreement, which aims to protect the local people’s livelihoods whilst conserving biodiversity (1). However, the successful management of these areas will very much depend on the support of the local people and the abandonment of destructive activities, such as slash-and-burn agriculture and hunting (7). Fortunately for the day gecko, Phelsuma  species breed well in captivity and the initiation of a captive-breeding programme for this gecko may well safeguard it from extinction (2). 

For more information on conservation in Madagascar, see:

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

  1. IUCN Red List (May, 2010)
    http://www.iucnredlist.org/
  2. Raxworthy, C.J. and Nussbaum, R.A. (1993) A new Madagascan Phelsuma, with a review of Phelsuma trilineata and comments on Phelsuma cepediana in Madagascar (Squamata: Gekkonidae). Herpetologica, 49: 342-349.
  3. CITES (May, 2010)
    http://www.cites.org/
  4. Phelsumania (May, 2010)
    http://www.phelsumania.com/public/systematics/species/phelsuma_antanosy_1.html
  5. Halliday, T. and Adler, K. (2002) The New Encyclopedia of Reptiles and Amphibians. Oxford University Press, Oxford.
  6. BBC – Gecko ‘begs’ insect for honeydew (May, 2010)
    http://news.bbc.co.uk/1/hi/sci/tech/7247472.stm
  7. Ramanamanjato, J., McIntyre, P.B. and Nussbaum, R.A. (2002) Reptile, amphibian and lemur diversity of the Malahelo Forest, a biogeographical transition zone in southeastern Madagascar. Biodiversity and Conservation, 11: 1791-1807.