Growth of the Mesopelagic Fish Vinciguerria attenuata (Cocco, 1838) in the Strait of Messina (Central Mediterranean Sea)

Abstract

The age and growth of the slender lightfish Vinciguerria attenuata are investigated for the first time by the analysis of otolith microstructure. A total of 242 individuals (standard length range = 15.3–39.0 mm) are collected from the Strait of Messina (central Mediterranean Sea). The analysis of the length–weight relationship highlights a hyper-allometric growth for all specimens, while when males and females are analyzed separately, the results point out an isometric growth for males and hyper-allometric growth for females, although no statistical differences emerge comparing sex curves (p-value = 0.06). Microincrement readings are considered valid only for 214 sagittal otoliths. Microincrement counts range from 31 to 49 (average = 39.9) in the otolith central zone, 28 to 53 (average = 43.2) in the middle zone, and 15 to 332 (average = 136.1) in the external zone. Overall, total microincrements range between 75 and 418. Different growth models (von Bertalanffy, Gompertz and logistic models) are taken into account to select the best-fitting model in describing the growth patterns in V. attenuata. The logistic growth model is selected as the best-fitting model, and its parameters for all individuals are L∞ = 38.597, k = 0.0104 and I = 122.4.