Fucus guiryi, Guiry's Wrack seaweed.Similar in morphology to Fucus vesiculosus, but distinguished from it by hermaphroditic receptacles, the presence of a pronounced receptacle sterile rim, monopodial branching, and the absence of bladders; by the shorter thallus and shorter frond length between the holdfast and the first dichotomy; by a less wide apical frond; by longer and wider receptacles; by a higher ratio of receptacle width:length and receptacle height:length; by higher intertidal zonation and physiological resistance to air exposure. .