Sargassum johnsonii leaves. Sargassum johnsonii Sargassum johnsonii Chapman, 1961, is a brown seaweed of the genus "Sargassum" that is endemic to the Three Kings Islands in New Zealand. It is sometimes called totara weed because of the resemblance to the foliage of the NZ native tree totara. Its scientific name derives from its discoverer, Magnus Earle Johnson, Three Kings Islands explorer and captain of the yacht "Rosemary", who landed botanists on the islands on several occasions. "Sargassum johnsonii" grows in rocky intertidal habitats, often extending to the subtidal zone up to a depth of 40 m. It is a foundation species, and
Mary Harriet Bate retains 361 of her plant specimens and the collection includes the rare shrub "Myoporum bateae" and the moss "Bryum bateae" named for her. Also there are the moss "Bryum viridulum" as well as the basidiomycete "Trametes heteromalla" , the alga "Sargassum laevigatum" and the tree "Eucalyptus bosistoana". All these were type specimens for the respective species which she collected. Her algal specimens were identified by Jacob Agardh, the fungal specimens by Mordecai Cooke and the bryophytes by Carl Müller. Bate was only one of Mueller's at least 220 female collectors, although she was one of the more prolific of them.