Caudal mucous pit on some species included: Caudal mucous pit The caudal mucous pit, or caudal mucous horn, is an anatomical structure on the tail end of the foot of various land snails and slugs, terrestrial pulmonate gastropod mollusks. The function of this pit is the resorption of mucus when the gastropod is moving (see also Muratov 1999). An incorrect and yet often-used term for this structure is the "caudal gland". This area also used to be referred to by the term "caudal pore". Families of snails and slug where a caudal mucous pit exists in every species included: Families/subfamilies where is caudal
Fish fin them if they want to herd a school of small fish, and also after periods of high activity, presumably to cool down. The oriental flying gurnard has large pectoral fins which it normally holds against its body, and expands when threatened to scare predators. Despite its name, it is a demersal fish, not a flying fish, and uses its pelvic fins to walk along the bottom of the ocean. Fins can have an adaptive significance as sexual ornaments. During courtship, the female cichlid, "Pelvicachromis taeniatus", displays a large and visually arresting purple pelvic fin. "The researchers found that males clearly