Preliminary study on ionic composition in endolynphatic sac of Hoplostethus mediterraneus

Silver Roughy, Hoplostethus mediterraneus (Cuvier, 1829) (Pisces; Thachichthyidae), is a benthopelagic cosmopolite fish. The samples of endolynph were collected from ten specimens with total length ranging between 14,7 cm and 22,2 cm, grouped in classes of 2 centimetres. Inductively Coupled Plasma - Atomic Emission Spectrometry (ICP-AES) Perkin-Elmer OPTIMA 3100 XL was used for the investigation of the ionic composition. A decreasing gradient in the ionic concentration [?g/l] among (versus) the smallest and biggest length classes was recorded for Ba, Cd, Mg, Na, Mn, B and Al.