40 



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across the rays or are restricted to the membrane between the rays. 

 Many specimens over 40 mm SL have two to three narrow, dark 

 longitudinal stripes or bands on the anal fin. On close examination, 

 all specimens are found to have these stripes but the area between the 

 stripes is sometimes almost as dark as the stripes themselves and thus 

 the pattern is obscured. 



Geographic variation. — (See also color pattern above.) Most 

 specimens from Tau Island and many from Tongatapu Island have 

 two or three pores before one or both anterior nostrils. Specimens 

 from the other localities, with rare exceptions, have only one pore 

 before each anterior nostril. 



In at least two populations of E. decussaUis, males appear to have 

 higher segmented dorsal fin ray averages than females. In the 

 Tongatapu population, of 23 males examined, 2 had 16 rays, 20 had 

 17 rays, and 1 had 18 rays. Of 23 females examined, 10 had 16 rays 

 and 13 had 17 rays. In the South China Sea and Gulf of Thailand 

 population, all 6 males examined had 17 rays; 5 females had 16 rays, 

 and 5 had 17 rays. Sexual dimorphism of other meristic characters 



TABLE 9.- 



-Frequency distribution of number of supraorbital cirri of specimens of 

 EntomacTodus decussatus arranged by SL classes (in mm) 



Classes 



12 3 4 5 6 7 



Cirri number 

 9 10 11 12 13 1'^ 15 16 17 18 19 20 21 22 23 2-4 25 26 27 28 



15-19.9 



20 



25 



30 



35 



40 



45 



50 



55 



60 



65 



70 



75 



80 



85 



90 



95 



100-109.9 



110 



120 



130 



140 



150 



13 



2-]. 1 



123-212-- - 

 -1-12111- - 



1-162 - 



122-4 - 



2--3 2 



2 2 2 



-11 



- 1 3 



- 1 - 



- - 1 



- 1 

 1 3 



- - 1 



- 1 - 



- 1 - 1 



- - 2 - 



1-31 



- 1 - - 



1 - - 1 

 - 1 - 1 



