Pethia tiantian Pethia tiantian Pethia tiantian is a species of cyprinid fish that has only been recorded from streams in the vicinity of Putao in the far north of Myanmar. It grows to a length of SL. It is generally brownish with a dark vertical bar just behind the operculum and a round dark blotch on the caudal peduncle. Other "Pethia" species are similarly marked but "P. tiantian" can be distinguished by its longer lateral line, reaching all the way back to the base of the caudal fin. "P. didi", a similarly marked species found in the same drainage basin, differs from
Operculum (gastropod) are attached with their head to the lowermost layer. The operculum grows in size as the shell grows, such that the operculum remains in proportion to the apertural size. In many species, when the animal is active and crawling, part of the underside of the shell rests on the outer surface of the operculum. In many species of marine shelled snails which live subtidally, the operculum is greatly reduced in size, and no longer serves to seal the shell entrance. In a large number of families it has been eliminated completely. In species of conchs, the operculum is elongated and