Sanchez et a\ Morphometry of juvenile and subadult Loligo pea/e/and L plei 



543 



GW/ML, and GW/RW, and means were higher for these 

 indices in females. Overlap occurred in all indices. 



Species comparisons 



The specimens of Loligo pealei used in species com- 

 parisons ranged in size from 37.0 to 147.0 mm ML, 

 whereas specimens of L. plei ranged in size from 29.0 

 to 148.0 mm ML. Results of statistical analyses of 

 tests of species comparisons for characters and indi- 

 ces are shown in Table 6. 



There were significant differences in the slopes of 

 the regression lines for all characters except HW and 

 RW. Variability in W was low in both species and 

 overlap occurred in only the smaller size classes ( Fig. 

 8). Coefficients of determination also were high for 

 FL, FW, GW, NCL, and RW in both species; however, 

 overlap occurred in all characters (Figs. 9-13, respec- 

 tively). Arm length and FCL were highly correlated 

 with mantle length only in L. pealei. 



Significant differences occurred in the slopes of the 

 regression lines for the following indices: AL/ML, 

 FCL/ML, FL/ML, FW/FL, GW/ML, NCL/ML, RW/ 

 ML, TL/AL, and W/ML. With the exception of W/ML 

 for L. pealei, the coefficients of determination were 

 low. Although little of the variability was explained 

 by the regression lines for GW/RW regressed on 



mantle length, a scatter plot of the GW/RW ratios 

 showed minimal overlap; thus this index may have 

 predictive value in separating juveniles and sub- 

 adults of the two species (Fig. 14). Significant differ- 

 ences were found between mean indices for all but 

 FW/FL and NCL/FCL. Mean indices were greater in 

 L. pealei for all ratios with the exception of RW/ML 

 and TL/AL. 



Overlap was high for all indices with the excep- 

 tion of GW/RW Both the scatter plot (Fig. 14) and 

 frequency histogram (Fig. 15) showed relatively low 

 overlap in the GW/RW indices. The GW/RW index 

 was higher for L. pealei in most instances. Only 9% 

 of the L. pealei specimens were in the range of over- 

 lap, and this overlap was more common in smaller 

 squid, including a distinct mode of small L. pealei 

 within the GW/RW range of L. plei (Fig. 15). 



Discriminant function coefficients were highest for 

 cartilaginous structures. Results of discriminant 

 analyses showed that no character, index, or combi- 

 nation of the two, classified L. pealei with 100% ac- 

 curacy (Fig. 16; Table 7). Rachis width in combina- 

 tion with NCL enabled separation at an accuracy 

 level of 93%, and in combination with FCL or GW 

 separated 95% of the specimens of L. pealei. Indices 

 that allowed separation of L. pealei from L. plei at ac- 

 curacy levels of 92% and above included the GW/RW 



