Crescimento relativo e determinação da idade na fase juvenil de Armases angustipes (Dana) (Decapoda, Brachyura, Grapsidae)

The relative growth of the male chelipod and female abdomen of Armases angustipes (Dana, 1852) was studied in order to determine the carapace size of puberty. Also, the age of juvenile crabs in laboratory was established. A total of 537 males and 557 females were analysed and the transition point between mature and immature stages was determined for both sexes. Males attain maturity at 1.00 cm carapace width and females at 1.08 cm. The relative growth of female abdomen was more remarkable than that of the male chelipod, although both are positive allometric. It suggests a greater importance of a large abdomen in females than a strong chelipod in males. Juvenile crabs reared from megalopa stage has five developmental stages before reaching sexual differentiation. This occurs in the sixth juvenile stage, when the intermolt stages become longer. The potential equation between carapace width and accumulated duration of juvenile stages is described as CW = 0,047D0,508