Life-history traits and reproductive strategies of Pegusa lascaris and Buglossidium luteum in the Ártabro Gulf

Reproductive biology plays a key role in fish population dynamics and sustainable fisheries management. Howev-er, detailed reproductive data remain particularly scarce for many species of low commercial interest. This study investigates the biology and reproductive strategies of two sole species (Pegusa lascaris and Buglossidium luteum) in the Ártabro Gulf, NW Iberian Peninsula. Sampling was conducted quarterly between 2017 and 2024, and 203 bottom trawl hauls were taken at 13 stations (10–50 m depth). All specimens were measured for length and weight, and sex and maturity stage were recorded macroscopically. Both species showed hyperallometric growth patterns, with females dominating at larger sizes. The spawn-ing period for P. lascaris occurred from May to September, whereas that of B. luteum occurred between March and August. Size at maturity analysis (L50) revealed that P. lascaris matured at 133.6 mm and B. luteum at 80.7 mm. Gonad samples were processed histologically to confirm maturity stages and assess oocyte development. Histological examination confirmed that both species are batch spawners with asynchronous oocyte development. These results will enhance current knowledge of the biology and reproductive strategies of the two species and will significantly improve the input into the stock assessment process, particularly for P. lascaris.