Mesophyllum capense (Rosanoff) comb. nov (Rhodophyta, Corallinaceae) from South Africa

Lithophyllum capense Rosanoff (Rhodophyta, Corallinaceae) was described on the basis of herbarium specimens in Lamouroux's and Lenormand's herbaria in Caen, France. The specimens were epiphytic on Gelidium sp. from The Cape o f Good Hope, South Africa. The structure and systematics of the lectotype a nd paratype specimens are compared with material collected recently in Sout h Africa. The plants have markedly prominent, multiporate tetrasporangial c onceptacles and belong to the subfamily Melobesioideae. The presence of mon omerous growth, a single layer of non-flared epithallial cells, subepithall ial initials that are as long as or longer than subtending cells and simple spermatangial systems on the floor and walls of male conceptacles place th is species in the genus Mesophyllum: comparison with other known species of this genus shows that Mesophyllum capense (Rosanoff) comb, nov. is a disti nct species with a distribution restricted, as far as: is known, to South A frica. (C) 2000 Adac/Editions scientifiques ct medicales Elsevier SAS.