Cochlearia officinalis sensu lato (Brassicaceae) around northern Irish Sea coasts

Abstract

For over 100 years botanists have found it difficult to identify Cochlearia (Scurvygrasses) growing on salt marshes and muddy shores of the northern Irish Sea coasts. They have been variously identified as C. anglica L., C. officinalis L. and more recently C. atlantica Pobed. This study describes the history of recording Cochlearia plants on these shores and their varied morphology, and through cytological analysis demonstrates that they are derived from the hybrid between C. anglica (2n = 48) and C. officinalis (2n = 24) with 2n = 36.

Changes to the coastal flora of Wirral, Merseyside (v.c.58)

“…It was first found in 1939 but it is widespread in temperate Europe (Stace et al, 2015), so why is it more frequent in Sefton and to a lesser extent in Wirral than elsewhere in Britain? On the other hand, the Cochlearia x hollandica derivative is probably widespread in north-western Europe (Greenwood & McAllister, 2022).…”

“…hortii with the type described from plants in Wallasey Pool. Recent work (Greenwood & McAllister, 2022) showed that plants variously named as C. anglica or C. officinalis were of hybrid origin (C. x hollandica). C anglica has not been found in Wirral and C. officinalis only very rarely, possibly only as a casual as there are no old records for C. officinalis.…”