Pollen morphology of endemic species of the Gonospermum Less., Lugoa DC. and Tanacetum L. complex (Asteraceae: Anthemideae) in the Canary Islands (Spain), and its taxonomical implications

• Published in: Grana Vol. 47; no. 4; pp. 247 - 261
• Main Authors: Ramos, Irene E. La Serna, Mederos, Miguel A. Padrón
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 01-12-2008
• Subjects: Canary Islands; endemic taxa; Gonospermum; Lugoa; pollen; Tanacetum; Tanacetum parthenium
• ISSN: 0017-3134; 1651-2049
• DOI: 10.1080/00173130802598074

The pollen of nine endemic taxa of the Gonospermum Less., Lugoa DC. and Tanacetum L. complex and of T. parthenium L. (introduced species from the Canary Islands) was studied using light and scanning electron microscopy with the aim of extending the knowledge of their morphology and to investigate whether pollen morphology may help clarifying the controversial taxonomy of these taxa. Twenty six populations in the Canary Islands (Spain) were studied and the following parameters were measured: polar axis (P), equatorial diameter (E), polar exine thickness (Ex1), length (L) and thickness (A) of the spines in the meridional optical section, exine thickness at the centre of the mesocolpium in the interapertural area (Ex2) and distance between spines (De) in the equatorial optical section. The studies show that the pollen of the three genera is very similar regarding shape, apertures, and ornamentation, but may be distinguished by size and exine thickness.