Study of sexual dimorphism in morphometric characters of the moon crab Matuta victor (Fabricius, 1781) in Gehrdo coast, Oman Sea

Abstract

Introduction: This study was done monthly on sandy coast of Gehrdo located in southwest of
Sirik city from December 2019 to November 2020.
Materials & Methods: Sampling was done randomly using net. Overall, 310 individuals of
M. victor were collected.
Results: Of these, were distinguished 181 males and 129 females. Carapace width range of
male and female crabs were obtained 16.4-44.3 mm and 19.3-36.9 mm respectively. Also,
weight range of male and female crabs were obtained 1.75-37.83 mm and 3.22-16.79 mm
respectively. In this study, maximum collected male and female crabs were observed in length
range of 19.8-23.2 mm and 26.6-30 mm respectively. There were not any female crabs in length
range of 40.2-43.6 mm and 43.6-47 mm. The positive and negative allometric growth were
observed for male and female crabs respectively. Also, exponential value (b) estimated of male
crab (3.11) was significantly more than of female crab (2.75) (P<0.05). Regression analysis of
relative growth between carapace length and carapace width showed significant difference
between males and females. Among the studied parameters, proportion of Sternum width,
distance between two spines, first abdomen width was significantly more in females (P<0.05).
On the other hand, proportion of chela length was significantly more in males (P<0.05).
Conclusion: The results derived of this study can useful for conservation of M. victor with
aimed to preserve the biodiversity.