Upside Down Catfish (Synodontis sp.)

Most fish use countershading — a dark back and pale belly — to blend in when viewed from above or below. This catfish flips that logic along with its whole body: swimming upside down for the majority of its life, it's developed reversed countershading, a darker belly and paler back, so the camouflage still works relative to which way is actually "up" for the fish.

Care level: Easy · Temperament: Peaceful, shoaling · Max size: ~4" · Min tank: 30 gal · Diet: Omnivore, sinking pellets/frozen