Hydroclathrus is a genus of perforate (pierced with holes) brown alga, of the phylum Ochrophyta and the class Phaeophyceae.

This genus currently has six (6) taxonomically accepted species:[1] The thalli of Hydroclathrus are vesicular or irregular ovate that later becomes hollow with many pores, giving them a net-like appearance (clathrate).

[2] Research determined that Hydroclathrus clathratus, together with another seaweed, Colpomenia sinuosa, displays a heteromorphic reproductive cycle.

[4] The genus Hydroclathrus is found throughout the tropical and warm temperate regions of the Pacific, Indian, and Atlantic oceans.

[5] They inhabit shallow intertidal waters, and during the peak season, they grow in high density at various ecosystems such as, seagrass beds and coral reefs.

This further validates the role of seaweeds in marine biogeochemical cycles, and the release of organic nutrients to coral reef systems.

The residue powder of Hydroclathrus clathratus after being extracted most of its active components in methanol were used as absorbent material for wastewater treatment from excess heavy metals such as cadmium and copper.