Round Island day gecko (Phelsuma guentheri)

French: Gecko Diurne De L'Ile Ronde, Phelsume De L'Ile Ronde
Spanish: Geco Diurno De Guenther
GenusPhelsuma (1)
SizeMale snout-vent length: 133 mm (2)
Female snout-vent length: 120 mm (2)
Total length: up to 300 mm (2)

The Round Island day gecko is classified as Endangered (EN) on the IUCN Red List (1) and is listed on Appendix II of CITES (3).

Stocky in shape, the Round Island day gecko is one of the largest day geckos of this genus. The colouration is a dull brownish-grey with a dark stripe connecting the nostrils, eyes and the ear hole. On the back dark spots may be present. In some individuals, the legs and toes have light yellow bars. The ventral side is white or yellowish. Unusually for the genus Phelsuma, the pupil of this gecko is vertically elliptical during the day (2).

The Round Island day gecko lives only on Round Island, which is about 20 kilometres northeast of Mauritius in the Indian Ocean (4). It was previously present on mainland Mauritius and Reunion Island before introduced predators like rats and cats and mongooses were introduced and hunted it to local extinction (2) (5).

The Round Island day gecko is found on bottle palms, fan palms and Pandanus plants, but due to the destruction of these plants by tropical cyclones and over-grazing by goatsand rabbits over the last 150 years, this gecko is also forced to live in lava rock crevices (4) (5). The island has high rainfall and an average temperature of 23 degrees Celsius (4).

The Round Island day gecko feeds on insects and other invertebrates, and is also known to lick pollen, nectar and ripe fruit (5).

Breeding all year round, the Round Island day gecko lays two eggs per clutch and up to six clutches per year. In the wild, eggs are often found in communal egg-laying sites stuck to the underside of rocks (2).

Over-grazing by goats and the massive impact of tropical cyclones on the vegetation of the island has resulted in a population reduction of this gecko to as few as between 600 to 1,500 individuals (6). The successful eradication of rabbits and goats and the very slow reforestation on Round Island led to a steady increase in numbers over the last decades (2).

A captive breeding programme has taken place at the Durrell Wildlife Conservation Trust, (formerly Jersey Wildlife Preservation Trust), but is no longer run (5). The population on Round Island is monitored on a regular basis (2).

For further information on geckos see the Phelsumania website:

Information authenticated by Matthias Goetz of the Durrell Wildlife Conservation Trust

  1. IUCN Red List (October, 2004)
  2. Goetz, M. (November, 2004) Pers. comm.
  3. CITES (October 2004)
  4. Phelsumania (October 2004)
  5. The Free Dictionary (October, 2004)
  6. Virtual Museum of Natural History (October, 2004)