What is "meristics"

n. 1 (context ichthyology English) The counting of quantitative features of a fish, such as its number of fins or of scales. 2 (plural of meristic English)Category:English plurals

Meristics is an area of ichthyology which relates to counting quantitative features of fish, such as the number of fins or scales. A meristic (countable trait) can be used to describe a particular species of fish, or used to identify an unknown species. Meristic traits are often described in a shorthand notation called a meristic formula.

Meristic characters are the countable structures occurring in series (e.g. myomeres, vertebrae, fin rays) in fish. These characters are among the characters most commonly used for differentiation of species and populations. In the salmonids, scale counts have been most widely used for the differentiation of populations within species. In rainbow and steelhead trout the most notable differences among populations occur in counts of scales.

Meristic characters are used in many other fields, such as in botany or in zoology. Meristic comparison is used in phenetic and cladistic analysis.