Anatomie

Methods of measurement
Total length:	The greatest dimension between the anteriormost projecting part of the head and the farthest tip of the caudal fin (the caudal rays are pressed together).	Fig. I, a-o
Standard length (= body length):	The distance from the anteriormost tip of the snout or upper lip to the posteriormost point of the fold formed when the caudal peduncle is bent	Fig. I, b-m
Fork length:	In fishes with a forked caudal fin, the distance from the anteriormost tip of the snout or upper lip to the anteriormost point of the caudal posterior margin	Fig. I, b-n
Body:	The greatest dimension, exclusive of fins, and fleshly or scaly structures, which pertain to the fin base.	Fig. I, h-i
Preanal length:	The distance from the anteriormost tip of the snout to the center of the anus
Head length:	The distance from the anteriormost point of the farthest margin of the pectoral fin	Fig. I, b-e
Caudal peduncle length:	The distance from the base of the last anal ray to the posterior en of the hypural bone	Fig. I, j-m
Caudal peduncle depth:	The least depth of the caudal peduncle	Fig. I, k-l
Snout length:	The distance from the most anterior point of the snout or upper lip to the front margin of the orbit	Fig. I, b-c
Eye diameter or orbital length:	The greatest distance between the free orbital rims	Fig. I, c-d
Interorbital width:	The least width between the eyes	Fig. I, p-q
Length of the upper jaw:	The distance from the most anterior point of the premaxilla to the posterior end of the maxilla
Mouth width:	The greatest transverse distance across the opening the mouth
Pectoral fin length:	The distance from the extreme base of the uppermost ray to the farthest tip of the fin	Fig. I, f-g
Counting scales
Lateral line scale count:	The number of scales on the lateral line from the scales on the posterior end of the hypural bone	Fig. I, 10
Scales above lateral line:	The number of scale rows above the lateral line from the origin of the dorsal fin, including the small scales, and counting downward and backward following the natural scale row to, but not including the lateral-line scale.	Fig. I, 27
Scales below lateral line:	The number of scale rows below the lateral line is counted similary to that for rows above lateral line. The count is made upward and forward from the origin of the anal fin. In this count, as in the one above the line, the small scales are included	Fig. I, 28
Counting vertebrae
Vertebrae:	In teleosts the number of vertebrae is counted from the foremost precaudal vertebra articulating with the cranium, to the caudal vertebra attaching to the first ural vertebra.
Counting gill rakers
Gill rakers:	The number of gill rakers on the outside of the first gill arch, shown by 2 figures separated by a plus sign (+).	Fig. I, E
Counting fin rays
Fin rays:	There are 2 kinds of fin rays, i.e., the spines and the soft rays. Spines are unpaired structures, without segmentation, and designated by large Roman numerals (I; II, …). Soft rays, designated by the Arabic numerals (1, 2, …), are usually, though not always, branched and flexible, and are bilaterally paired and segmented. In a fin containing both spines and soft rays, the count for the spines is separated (e.g., XI-18). If the two sections are joined, a comma is used (e.g., XI,18).
Counting branchiostegal rays
Branchiostegal rays:	The total number of the rib-like slender bones located below the opercular bones and supported by the membrane	Fig. I, 15

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