1) Arthropod genus 2) Genus portunus 
Portunus is a genus of crab which includes several important species for fisheries, such as the blue swimming crab, Portunus pelagicus and the Gazami crab, P. trituberculatus. Other species, such as the three-spotted crab (P. sanguinolentus) are caught as bycatch. The genus Portunus contains more than 90 extant species and over 40 further species ...
(from the article `swimming crab`) ...the fifth (hindmost) pair of legs are flattened into paddles for swimming. The family includes the blue crab (q.v.), an edible crab of the ...
In Roman mythology, the god of gates and doors (Latin portae). He was gradually transformed into a protector of harbours (Latin portus). ...
[n] - type genus of the family Portunidae
genus Portunus noun type genus of the family Portunidae