Hemitaeniochromis Hemitaeniochromis Hemitaeniochromis is a small genus of cichlid fishes endemic to Lake Malawi in east Africa. The genus is distinguished from other genera of Lake Malawi Haplochromini by details of its melanic color pattern and by its dentition. The color pattern includes (1) a midlateral horizontal stripe starting at least an eye length behind the operculum, this stripe broken into separate spots at least on its front half, more nearly continuous on its rear half, extending to the end of the caudal peduncle; (2) a second (supralateral) stripe above the midlateral one that is only on the front part of
Operculum (fish) the shape is visible and then the individual components are developed days later. The size and shape of the operculum bone is dependent on the organism's location. For example, fresh water threespine sticklebacks form a less dense and smaller opercular series in relation to marine threespine sticklebacks. The marine threespine stickleback exhibits a larger and thicker opercular series. This provides evidence that there was an evolutionary change in the operculum bone. The thicker and more dense bone may have been favored due to selective pressures exerted from the threespine stickleback's environment. The development of the operculuar series has changed dramatically