Hydroclathrus clathratus (C. Agardh) M. Howe, 1920

Belleza, Dominic Franco C., Tateishi, Hiroto, Tanimae, Shin-Ichiro, Kobayashi, Taishun, Aota, Tomoyuki, Urasawa, Toshiki & Nishihara, Gregory N., 2025, An annotated list of brown seaweeds (Phaeophyceae) from Nakadori Island (northern Goto Islands, Nagasaki, Japan), Phytotaxa 694 (1), pp. 1-24 : 12-13

Hydroclathrus clathratus (C. Agardh) M. Howe, 1920

Japanese name: カゴメノリ (kagomenori)

Basionym: Encoelium clathratum C. Agardh, 1823

Lectotype locality: — Belle-île , Brittany, France

Description and remarks: —Specimens in the collection differ greatly in size, having widths of 5 cm to over 30 cm. This species generally has a net-like, heavily perforated thalli that are flat and spread-out or clumped and convoluted. The holes of the thallus vary in widths of 1 mm to 6 cm in diameter. Larger holes are generally observed to have a dark and thickened borders while smaller holes do not.

This species is observed to form extensive mats on the bottom from March to June in our study sites. This species also has potential as feedstock for biogas production ( Marquez et al. 2014).

Materials examined: —18ECS1-7 (2 to 16)