The existence of huge clusters of T/NK cells on all sides of gill arches, at The bottom in the efferent element of filaments, was unanticipated. Our investigations disclosed that these clusters constitute a completely new structured lymphoid tissue, which we name the “Amphibranchial Lymphoid Tissue” (ALT). IMAGES and other media https://frozen-atlantic-mackerel14969.madmouseblog.com/11372244/about-mackerel-scomber-scombrus