is a feature which can also be used to classify fish species. Usually all the vertebrae are counted. Vertebral counts may be split into abdominal (those associated with the body cavity) and caudal (tail) vertebrae. If there are sutures in the urostyle, components are counted, otherwise the urostyle is usually counted as one vertebra. Gill raker counts The number of gill rakers on the first gill arch can also be used to identify a fish species. Rakers are counted for the upper and lower limbs of the gill arch, and a raker at the joint of the upper and lower limbs is counted as of the lower. Counts for the upper and lower limbs are separated by a + sign and ranges are bracketed, e.g., GR: 3 + (4-5). See also Morphometrics References External links Chase, P. D. (2014) "Meristics". In: Steven X. Cadrin, Lisa A. Kerr and Stefano Mariani (Eds) Stock Identification Methods: Applications in Fishery Science, second edition, pp. 171–184. Academic Press. . Fish identification using meristics Practical fishkeeping. 26 July 2010. Ichthyology Marine biology Fish anatomy