Field Observations of the Lizards Gonatodes humeralis and G. ocellatus (Gekkonomorpha: Sphaerodactylini) in Trinidad and Tobago

Tal Seifan, Victor C. Quesnel, Nurit Werner, Yehudah L. Werner


This report, derived mainly from intensive observations of Gonatodes humeralis (on trees) on Trinidad and G. ocellatus (in culverts) on Tobago, islands of the West Indies, in May-June, 2000. It shows that these geckos are sit-and-wait foragers that prefer a perch posture with the head pointing down, irrespective of the height above the ground. This posture apparently enables better detection of better-illuminated prey. The height of the gecko above ground and its posture were not significantly affected by temperature or light. The coincidence of captive geckos dying when sloughing is discussed. Locality records presented include G. ocellatus from a new locality in Tobago, the Tobago mountains at approx.11 ' 17'N, 60 '36' W, altitude 460m. An additional, as yet unreported, species of Gonatodes may occur on Tobago.

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