Acetabularia major

Appearance

Thalli moderately calcified, consisting of a slender stalk and a terminal cap (up to 18 mm in diameter). Terminal cap made up of 63 to 85 sporangial rays, laterally attached to each other by calcification. Sporangial rays cylindrical-compressed, decreasing in diameter towards the centre of the cap, their terminal wall at the margin of the cap truncate to slightly emarginate. Distinct vertical notches present at the proximal half of the lateral walls of rays. Segments of corona superior 230 to 250 μm long, bearing 6 to 9 hairs or hair scars in an uniseriate row; segments of corona inferior 265 to 280 μm long with rounded, truncate or emarginate outer margins. Spores oval to spherical, up to 98 to 115 μm in diameter. Thalli up to 6 cm in height; the largest species among the genus Acetabularia.

Naming

Synonyms
Acetabularia crenulata var. major Sonder 1871
Acetabularia denudata Zanardini 1878
Acetabularia gigas Solms-Laubach 1895

Distribution

(as Acetabularia major G.Martens)
Asia: China (Liu 2008), Japan (Okamura 1936), South China Sea (Phang et al. 2016), Taiwan (Lewis & Norris 1987, Berger et al. 2003, Shao 2003-2014, Anon. 2012, Anon. 2012).

South-east Asia: Indonesia (Silva, Basson & Moe 1996), Philippines (Silva, Meñez & Moe 1987, Ang, Sin Man Leung & Mei Mei Choi 2014), Vietnam (Tien 2007, Nguyen et al. 2013).

Australia and New Zealand: Queensland (Lewis 1987, Phillips 1997, Phillips 2002, Bostock & Holland 2010).

(as Acetabularia crenulata var. major Sonder)
Asia: Taiwan (Shao 2003-2014).

South-east Asia: Indonesia (Atmadja & Prud'homme van Reine 2014).

(as Acetabularia denudata Zanardini)
Asia: Taiwan (Shao 2003-2014).

(as Acetabularia gigas Solms-Laubach)
Asia: Japan (Okamura 1936), Taiwan (Lewis & Norris 1987, Shao 2003-2014, Anon. 2012).

Habitat

Grows in colonies on rocks, shells and dead coral fragments in moderately wave-washed habitats near shores and in shallow waters.

Uses

Used as medicine for renal troubles.