Crocodile shark in a 1936 issue of "Zoological Magazine (Tokyo)" by ichthyologist Kiyomatsu Matsubara, based on a long specimen found at the Koti Fish Market in Japan. The type specimen is a long adult male found at a fish market in Su-ao, Taiwan. After being shuffled between the genera "Carcharias" and "Odontaspis" in the family Odontaspididae by various authors, in 1973 Leonard Compagno resurrected Jean Cadenat's 1963 subgenus "Pseudocarcharias" from synonymy for this species and placed it within its own family. The morphology of the crocodile shark suggests affinity with the megamouth shark (Megachasmidae), basking shark (Cetorhinidae), thresher sharks (Alopiidae), and mackerel
Fish anatomy gonads). Much like the mammalian immune system, teleost erythrocytes, neutrophils and granulocytes are believed to reside in the spleen whereas lymphocytes are the major cell type found in the thymus. In 2006, a lymphatic system similar to that in mammals was described in one species of teleost fish, the zebrafish. Although not confirmed as yet, this system presumably will be where naive (unstimulated) T cells accumulate while waiting to encounter an antigen. Fish anatomy Fish anatomy is the study of the form or morphology of fishes. It can be contrasted with fish physiology, which is the study of how the