Vol. 4, Issue 1, Part C (2022)

Morphometric characters relationships of the females and males red frog crab Ranina ranina locally named as “curacha” from Balut Island, Sarangani, Davao Occidental was the main goal in this study. The carapace width (CW), carapace length (CL), abdomen width (AW), abdomen length (AL), propodus length (PL), dactylus length and body weight were assessed. A total of 60 samples were sexed based on the shapes of the abdomens and examined in the laboratory. At the same time, the species body weight was also measured. Most of the females’ R. ranina has body size larger than males. This is due to differences in growth patterns, food availability and size of maturity. In terms of its body weight, females of R. ranina are usually smaller and reaching 400 g in weight while males can reach 900 g in total body weight. It is important to note that males must be large enough to successfully dig female crabs out of the sand to reproduce. The allometric regression found describes changes in soft tissue content (or total animal weight for crustaceans) relative to carapace width/length. This result is consistent with general trends of scaling with body size in animals.