Order Biddulphiales

Family Biddulphiaceae Kützing

Genus Biddulphia S. F. Gray

• Biddulphia granulata Roper — benthic, common, littoral, Velikaya Salma
• Biddulphia pulchella S.F. Gray — benthic, Velikaya Salma (Житина, 1981).

Genus Isthmia C. Agardh

• Isthmia enervis Ehrenberg — planktonic, sporadic, summer, Babje More (Бондарчук, 1963); on algae, rare, littoral, upper sublittoral, Malyi Eremeevsky Island, WSBS pier.
• Isthmia nervosa Kützing – marine, sublittoral; among macrophytes; rare (Бондарчук, 1970).

Genus Trigonium Cleve

• Trigonium arcticum (Brightwell) Cleve – marine, littoral, sublittoral; sporadic (Бондарчук, 1970: Triceratium arcticum Brightwell).

rus: Порядок Biddulphiales