We compared the number of microstructure of Anchoa tricolor (Agassiz, 1829) post-larvae sagittae otoliths in specimens fixed in formalin 10% in different periods of conservation (four days versus four years). Significant differences were found in the number of microstructure for post-larvae ranging from 20-26 mm total length (TL), with averages of 18.6 microstructures (± 0.75 standard error) for fishes preserved for four years, and 35.3 microstructures (± 1.28 standard error) for fishes preserved for four days. Therefore, the number of post-larvae otoliths microstructure preserved for long periods can not be suitable to infer age or growth rates. Additionally, we failed in detecting and extracting otoliths in post-larvae smaller than 20 mm TL preserved due to its comparatively higher organic matter composition, mainly during the early life cycle.
Age; anchovy; post-larvae; conservation