https://aphotomarine.com/microalgae_diatom_licmophora_30-01-15.html
Licmophora sp. - A species of diatom on the hydroid Obelia geniculata 30.01.15. (Microalgae images)
APHOTOMARINE - A photographic guide to aid the recognition and identification of Licmophora sp. - A species of diatom on the hydroid Obelia geniculata...
on theobelia geniculataspeciesdiatomhydroid
https://speciesconnect.com/interaction/obelia-geniculata-eatenby-octopus-vulgaris/
Obelia geniculata Carnivory Octopus vulgaris - Species Connect
obelia geniculataoctopus vulgariscarnivoryspeciesconnect