Hypoglossum imperfectum nov spec. (Rhodophyta, Delesseriaceae), from the South African south coast

Hypoglossum imperfectum is described as new to science. It is a minute repe nt species collected in relatively deep water off the South African south c oast, in the Tsitsikamma Coastal National Park. It differs from all other s pecies of the genus by the possession, in fertile blades only, of stunted p roximal third-order cell rows, which thus do not reach the thallus margin. This is in violation of the generic definition that proclaims that in Hypog lossum (and the 'Hypoglossum group') all third-order cell rows reach the th allus margin.