Preliminary data on microcharacters and chromosome number in Tornabenea species (Apiaceae) from Cape Verde islands

• Autor(a) principal: Grosso, A.C.
• Data de Publicação: 2008
• Outros Autores: Rodrigues, L., Gomes, I., Martins, E.S., Teixeira, G.
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10400.5/5943
• topic: Apiaceae; Tornabenea; cytology; microcharacters; Cape Verde

Tornabenea is a small Apiaceae genus that is endemic to the Cape Verde Islands. Its species differentiation is based just on a few macromorphological characters: leaf shape, number and shape of umbel bracts and mericarp ribs. These characters vary within each species and show high plasticity. Thus, in recent taxonomic data of the genus, there are different viewpoints as to the number of species. Here, in order to improve the taxonomy of the genus, microcharacters of the vegetative and reproductive structures of three taxa—T. insularis, T. annua and T. tenuissima—have been examined. The shape and arrangement of hairs on the surface of the mericarps, and the presence and structure of starch grains are the only different microcharacters noted in T. insularis and T. annua. Chromosome number of the latter two species is 2n¼18. Our preliminary results disagree with the existing classifications of the genus Tornabenea. In fact, they do not lead to a clear separation between T. insularis and T. annua. By contrast, it is easy to distinguish between these species and T. tenuissima, which possesses more peculiar microcharacters