Sara Ferrando, Andrea Amaroli, Lorenzo Gallus, Stefano Aicardi, Davide Di Blasi, Marino Vacchi, Laura Ghigliotti


The olfactory organ of Chondrichthyes is characterized by a central raphe and several lamellae covered by the sensory olfactory epithelium; usually the lamellae have secondary folds on their surface. It is an overall complex shape and very variable among the species of this vertebrate class. The sensory olfactory epithelium, in turns, has a general organization which is conserved across species. We here describe for the first time the morphology and histology of the olfactory organ of a juvenile male of marbled electric ray Torpedo marmorata. It is constituted by an elongated raphe and 37 primary lamellae. As the lamellar number does not change ontogenetically and as a little variability among individuals, the number 37 is likely to be indicative as the lamellar number of the species, and it is the smaller to date reported in the order of Torpediniformes. NOS1-like immunoreactivity allowed to observe a basal cell population possibly involved in immune defense or in the regulation of cell renewal.


Electric ray, nitric oxide, olfactory epithelium, olfactory rosette

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