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Marginal and edge state analysis was carried out on sagitta otoliths and illicia of white anglerfish taken from ICES Sub-area VI and Division IVa between April 1999 and September 2000. This demonstrated that an annulus comprised a multi-ring opaque zone and a wide translucent zone. Narrow translucent zones within the wide opaque zones were found to be significantly narrower than the translucent zones separating them, suggesting that these were false rings. Opaque material was predominantly deposited during the summer months (July–September) and translucent material during the winter (December–February). Precision of increment readings was tested from repeated increment counts of the calcified structures. This indicated that the most consistent age readings came from sagitta otoliths sectioned through the sagittal plane.  相似文献   
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The early life history of the black anglerfish, Lophius budegassa was investigated by otolith (lapilli) increment analysis. Samples of demersal juvenile L. budegassa ranging from 54 to 196 mm total length were collected during bottom trawl surveys in the central Adriatic Sea. By counting increments presumed to be deposited daily in the lapillar otoliths, 88 specimens of L. budegassa were successfully aged. Age estimates of juveniles ranged between 79 and 204 days, indicating that probably the pelagic phase of this species is relatively short and settlement occurs at less than 3 months of life. The analysis of check marks in the core area of lapilli enabled us to determine the period of endogenous feeding, which would last between 15 and 24 days after hatching. Back-calculated hatching dates and, consequently, the spawning season of L. budegassa in the Adriatic Sea was spread over a long period, lasting at least from February to June. The length at age relationship gave an estimate of mean growth rate of approximately 0.8–1.02 mm/day, indicating a faster growth rate of 0+ juveniles L. budegassa than previously thought. The implications of these findings on age estimates discrepancies between previous ageing studies on L. budegassa carried out using different calcified structure (sagittae or illicia) are discussed.  相似文献   
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