The autecology of Elachista fucicola (Vell.) Aresch. and Elachista scutulata (Sm.) Duby.

Abstract

The genus Elachista was founded by Duby in 1830, and he placed Conferva scutulata Sm. in it. This is the type specimen of the genus and is figured in English Botany by Sowerby. The illustration is dated August 1st, 1811. Elachista scutulata (Sm.) Duby was first found by Mr. Borer at Brighton growing on Himanthalia elongata. The genus in Britain contains two other species, Elachista fucicola (Vell.) Aresch. and Elachista flaccida, Elachista fucicola (Vell.) Aresch. is the oldest known and the commonest species of the genus Elachista in Britain. Colonel Velley first discovered this brown alga and he gave a correct representation and description of it growing on Fuous serratus as Conferva fucicola in the year 1795, in his book, Coloured Figures of Marine Plants Found on the Southern Coast of England. Velley found this plant growing in great abundance, particularly in the spring under an elevated cliff near Weymouth called "The Look Out". The plant Velley described and figured is in his herbarium in Liverpool Museum and this is the type specimen of Elachista fuclcola. Areschoug in 1842 placed Velley's Conferva fucicola in the genus Elachista. Elachista flaccida (Dillw.) Aresch. In 1843 Areschoug placed this in the genus Elachista Harvey. Formerly there was a fourth species Elachista grevillei now reduced to a form of Elachista fucicola. E. grevillei was found by Dr. Greville in July 1852 growing on Cladophora rupestris at Largs. In the same year, but in the month of August, it was found by Professor Walker Arnott at Corrighills, Arran. The plant consists of a basal disc, from which assimilatory filaments and paraphyses arise.