Megamouth shark "M. applegatei" – have also recently been proposed on the basis of fossilized tooth remains. However, the Cretaceous-aged "M. comanchensis" has been recently reclassified as an odontaspid shark in the genus "Pseudomegachasma", and is in fact unrelated to the megamouth shark despite similar teeth morphology. The appearance of the megamouth is distinctive, but little else is known about it. It has a brownish-black colour on top, is white underneath, and has an asymmetrical tail with a long upper lobe, similar to that of the thresher shark. The interior of its gill slits are lined with finger-like gill rakers that capture
Feeder fish overcrowded or otherwise sub-optimal environment, they may also carry bacterial infections and parasites, which can be passed along to fish that eat them. A major disadvantage of using feeder fish, particularly goldfish, is that they do not actually simulate what tropical fish eat in the wild. Several fast-growing and hardy species are commonly sold and used as feeder fish. Depending on the locality, feeder fish may include: Although the use of feeder fish is fairly common in the United States, in the United Kingdom it is much less common, with aquarists and hobby magazines in Britain generally rejecting the use