The Identity of Anchusa zeylanica Vahl ex Hornemann (Boraginaceae)

Abstract

Summary. Cynoglossumfurcatum Wall. is shown not to be a synonym of C. zeylanicum (Lehm.) Brand. The problem dealt with here was met whilst I was writing up Cynoglossum for an account of the Boraginaceae of East Africa. The genus in this area is of great complexity with, on the one hand, populations very similar to European species and on the other populations virtually indistinguishable from Indian species; between the two is a complex of intergrading taxa. This is no surprise since the genus is known to be intrinsically difficult almost throughout its range. In his revision of the Boraginaceae of West Pakistan, Kazmi (1971) deals with several of the species also occurring elsewhere in India. A species long known as Cynoglossumfurcatum Wall. (1824), characterized by the soft indumentum of the leaves with hairs not obviously arising from tubercular bases or rings of cystoliths, is treated by Kazmi under the name C. zeylanicum '(Vahl) Thunb. ex Lehm'. Riedl (1967) used the same authority in Flora Iranica; Vahl, however, merely put a name on a herbarium sheet and Thunberg wrote a letter. C. B. Clarke (1883) who wrote up the family for the Flora of British India made zeylanicum a variety of C. denticulatum A. DC. (a much later name), a species which has the leaf-hairs arising from tubercles and thus rough to the touch. There are thus two quite different interpretations of the identity of the plant bearing the name C. zeylanicum. It is clear that neither Kazmi, who states 'type not indicated', nor C. B. Clarke saw any authentic material. Brand, who wrote up Boraginaceae-Cynoglosseae for Engler's Das Pflanzenreich (1921), was the originator of the confusion; he included furcatum under zeylanicum despite the fact that he did actually examine the types. The name Anchusa zeylanica was written by Vahl on a sheet in his herbarium