Resumen

TAPIA, Héctor J.; ARIAS, Salvador; YANEZ-ESPINOSA, Laura  y  TERRAZAS, Teresa. Using stem spines in the identification of Neobuxbaumia species (Cactaceae). Rev. Mex. Biodiv. [online]. 2016, vol.87, n.2, pp.288-300. ISSN 2007-8706.  https://doi.org/10.1016/j.rmb.2016.04.006.

This study evaluated the morphometry of spine variables, orientation and length, in order to investigate the utility of spination patterns for species identification within the genus Neobuxbaumia (Cactaceae: Cactoideae: Echinocereeae). This analysis is based on a traditional taxonomic identification method and on multivariate statistical tools. Spine variables were recorded on preset categories relying on the areole organization. We obtained basic circular descriptive statistics and built graphs representing the spination pattern of each species. Canonical discriminant and classificatory analyses were applied from an -a priori- assignation of species. The ability to assign individuals to their species was 89.6%, on average. The orientation and length of the spines showed potential to identify most of the species of Neobuxbaumia, as well as the related species Pseudomitrocereus fulviceps. The complementary use of other vegetative morphological characters enables a more robust identification of species, as reflected on the identification key included. The recognition of spination patterns is considered of taxonomic value to identify species in other cacti groups in absence of reproductive structures.

Palabras llave : Morphometry; Spination pattern; Orientation of spines.