Validation of oviparous and viviparous ICES maturity scales through histological analysis

One of the main Tor’s of the WKSSEL2 workshop was to perform histological analyses from different structures of elasmobranchs to better confirm the validation of the macro scales per-formed in the previous WKSSEL workshop. With the intent to give a contribution to this term of reference, a description of the macroscopic and microscopic characteristics of each stage of oviparous and viviparous scales have been presented. With regard to the oviparous scales, the main features of macroscopic and histological images of the shark Galeus melastomus and the skate Dipturus oxyrinchus have been shown. Concerning the viviparous, the characteristics of two species (Etmopterus spinax and Squalus blainville) have been shown. A suggestion to amplify the description of the stage 3 (b,c,d) of viviparous scales also to the ovaries was given. This advice derives from the fact that the two species analyzed present at 3 stages a different ovaries activity: the former shows inactive gonads while the latter active ones.