HETEROCHELY IN THE THREE-SPOT SWIMMING CRAB, Portunus sanguinolentus Rusydi Rozaimi, Hanafiah Fazhan, Mhd Ikhwanuddin, Khor Waiho
Higher Institution Centre of Excellence (HICoE), Institute of Tropical Aquaculture and Fisheries, Universiti Malaysia Terengganu, 21030, Kuala Nerus, Terengganu, Malaysia.
Abstract
Three-spot swimming crab, Portunus sanguinolentus is one of the edible species that can be found in Malaysian waters. Although, this species categorized as non-targeted species but still can be found in most fish market. Chela handedness is very widespread among decapods which is the order for this species but there is no publication regarding handedness in the three-spot swimming crab, P. sanguinolentus. The purpose of this study is to determine chela handedness in P. sanguinolentus and to determine if chela handedness is affected by sex and maturation status. Due to COVID-19 restrictions, sampling of this species was assisted by local fishermen. Chela morphometric measurements (propodus length, propodus width, propodus diameter, carpus length and dactylus length) were compared using paired t-test to determine right and left-handedness based on sex and maturation status. Mature specimens showed obvious chela handedness (P < 0.05) whereas, no obvious difference was observed in most chela measurements of immature specimens (P > 0.05). The results also indicate that chela handedness was more dominant on the right chela of matured male crab compared to matured female crab. This study filled in the knowledge gap regarding chela handedness on P. sanguinolentus and agree with the right-handed dominance observed in most brachyurans.
