Abstract
Ovigerous females of the species Geograpsus crinipes (Dana, 1851) were collected from the Rabigh coast of the Red Sea. The morphology of the first zoeal stage is illustrated and described in detail from laboratory-hatched material. The characteristic features of this stage are compared with those of the closely related first zoeal stage larva of G. lividus (H. Milne Edwards, 1837) from the Pacific coast of Panama, the Gulf of Mexico and Jamaica. Morphological differences with respect to the larvae of G. lividus populations are discussed.