Rhizoprionodon longurio (Compagno, 1984)

Gayford, Joel H, Whitehead, Darren A, Ketchum, James T & Field, Daniel J, 2023, The selective drivers of allometry in sharks (Chondrichthyes: Elasmobranchii), Zoological Journal of the Linnean Society 198 (1), pp. 257-277 : 263-264

Rhizoprionodon longurio (all classes)

Regression of 11 morphological measurements against PL in all R. longurio individuals recovered five cases of isometric growth and six cases of allometric growth ( Table 7). R 2 values varied from 0.54 (KC; Table 7) to 0.96 (LS, FS, PS; Table 7). The measurements LS, FS and PS all showed significant positive allometry, whereas the measurements DW, DL and UL showed significant negative allometry ( Fig. 7 ; Table 7).

Rhizoprionodon longurio (neonates excluded)

Regression of 11 morphological measurements against PL in all R. longurio individuals from Classes Two and Three recovered ten cases of isometric growth and one case of allometric growth ( Table 8 ). R 2 values varied from 0.19 (KC; Table 8 ) to 0.81 (FS; Table 8 ). The measurement UL showed significant negative allometry ( Fig. 8a ; Table 8 ).

Figures

Figure 7. Linear regression plots for LS (A), FS (B), PS (C), DW (D), DL (E) and UL (F) against PL for all R. longurio data. All data are log10 transformed, and the 95% confidence interval for the scaling coefficient is represented by the dark-grey area. Lateral span - LS (A), frontal span - FS (B), proximal span - PS (C), dorsal fin width - DW (D), dorsal fin length - DL (E) and upper caudal lobe - UL (F) against precaudal length - PL for all R. longurio data. All data are log10 transformed, and the 95% confidence interval for the scaling coefficient is represented by the dark-grey area.

Figure 8. Linear regression plots for upper caudal lobe - UL in R. longurio following exclusion of neonates (A), dorsal fin length - DL in R. longurio Class Two (B) and upper caudal lobe - UL in R. longurio Class Three (C) against precaudal length - PL. All data are log10 transformed and the 95% confidence interval for the scaling coefficient is represented by the dark-grey area.