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
Paradise fish predators, eating insects, invertebrates, and fish fry. The popularity of this species has waned in recent decades as much more colorful (and often less pugnacious) species of gouramis have become widely available to hobbyists. This species is one of the few fish that can change its color (lighter or darker) in response to stimuli. It also appears that paradise fish are capable of learning through a type of restrictive process. Most forms of active teaching seem to hinder the paradise fish's ability to learn. Paradise fish are tolerant of a wide range of water conditions, surviving in cool and warm