Georgette Douwma / Stinging hydroid (Aglaophenia cupressina). North Sulawesi, Indonesia.

Georgette Douwma / Stinging hydroid (Aglaophenia cupressina). North Sulawesi, Indonesia.

Solvin Zankl / Shrimp (Hippolyte coerulescens), Hydroids (Aglaophenia latecarinata) and Sargasso barnacles (Lepas pectinata) on Broad-toothed gulfweed (Sargassum fluitans) Sargasso Sea, Bermuda

Alex Mustard / 2020VISION / Female Ghost shrimp (Caprella linearis) amongst the branches of Stinging hydroids (Aglaophenia cupressina), Loch Carron, Ross and Cromarty, Scotland, UK, April

GEORGETTE DOUWMA / Hydroid {Aglaophenis cupressina} Sulawesi, Indonesia its powerful sting is dreaded by

Jose B. Ruiz / Colonial hydroids {Aglaophenia pluma} Mediterranean- (small yellow balls are corvulae of sexual reproduction

Nature Production / Hydroid {Aglaophenia whiteleggei} Izu Osezaki, Shizuoka, Japan, March

Alex Mustard / Coral reef scene with multiple species of Princess anthias (Pseudanthias smithvanizi), Threadfin anthias (Pseudanthias huchti), Redfin anthias (Pseudanthias dispar) and feathery hydroids (Aglaophenia...

David Fleetham / Stinging hydroid / Fire hydroids (Aglaophenia cupressina)Yap, Micronesia, Pacific Ocean. Hydroids are small predators that look like plants and are related to jellyfish.

Alex Mustard / Barrel sponges (Xestospongia testudinaria) grow in shallow water, surrounded by hydroids (Aglaophenia cupressina), in shallow water beneath trees and sun burst. The Passage betweeb Waigeo Island and G...

Franco Banfi / Toothed feather hydroid (Aglaophenia pluma), South Tenerife, Canary Islands, Atlantic Ocean.