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Abstract
Daily growth increments in sagittae and lapilli of ling (Genypterus blacodes (Schneider, 1801)) larvae and juveniles were investigated. Increment counts of sagittae and lapilli of wild fish were similar up to a length of c. 20 mm total length (TL) (≍50 days old), after which counts on sagittae were higher than for lapilli. Three individuals were kept alive and treated with Alizarin Complexone to determine whether increments formed on a daily basis. The number of increments visible in the lapilli and sagittae after the mark was close to that expected in two of the three fish. In the third fish, the agreement was good for the lapillus but the number of increments on the sagittae was higher than expected. It is believed that subdaily increments cause the overestimation of age in the sagittae. Consequently, the lapillus is considered to be a better structure for daily increment analysis than sagitta in larvae and juveniles of ling.