COLLETTE and RUSSO: SPANISH MACKERELS 



Morphometric Characters 



In addition to fork length, 26 measurements 

 routinely were made on all specimens destined to 

 be dissected, to insure that these data would 

 be available if needed. Preserved material also 

 was measured until an adequate sample was 

 obtained. Measurements follow the methods of 

 Marr and Schaefer (1949) as modified by Gibbs 

 and Collette (1967) and Collette and Chao (1975). 

 Morphometric characters can be used to separate 

 species and populations within species. Tables 

 showing the 26 characters as thousandths of fork 

 length and 8 characters as thousandths of head 

 length are presented in the systematic section of 

 the paper (see Tables 13-30). Most of the charac- 

 ters are best used at the species level; therefore, 

 only a summary table of the means of proportions 

 (Table 1) is presented in this section. Where there 

 was sufficient material from two or more poten- 

 tially different populations, analysis of covari- 



ance (ANCOVA) was carried out on the regres- 

 sions of body parts on fork length. Results are 

 reported, under a section entitled Geographic 

 Variation, in 11 of the 18 species accounts. Tests 

 of significance were made by Newman-Keuls 

 Multiple Range Test. 



Meristic Characters 



Countable structures are of special value sys- 

 tematically because they are relatively easy to 

 record unambiguously and are easy to summarize 

 in tabular fashion. Meristic characters that have 

 proved valuable systematically in Scomberomo- 

 rus include numbers of fin rays (first dorsal 

 spines, second dorsal rays, dorsal finlets, anal 

 rays, anal finlets, and pectoral rays), gill rakers, 

 teeth on the upper and lower jaws, vertebrae 

 (precaudal, caudal, and total), and lamellae in 

 the olfactory rosettes. Olfactory lamellae are dis- 

 cussed as the next to last section under soft 



TABLE 1. — Morphometric comparison of the species of Scomberomorus. Means as thousandths of fork length or head length. Species 

 arranged alphabetically by the first three letters of their names. Ranges for the species given in Tables 13-30. 



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