lb28's picture

Bladder wrack

Observed: 8th April 2011 By: lb28lb28’s reputation in Plants
Bladder wrack
Species interactions

No interactions present.


AlanS's picture

This is Fucus vesiculosus (Bladder Wrack)

F. vesiculosus often lacks bladders, but there is one bladder visible in the photograph (lower right) - enough to rule out F. spiralis.

The structures at the ends of the fronds are not bladders; they are conceptacles (sexual structures). There is a lot of variation in Fucus, sometimes at least due to hybridisation, but in F. spiralis they are generally ovoid, with a distinct, frilly margin. In F. vesiculosus they are pointed and simply have keeled margins.

To me, this is a typical representation of a common form of F. vesiculosus.