Análisis morfológico y anatómico del complejo Myriopteris lendigera (Pteridaceae) en México

Abstract

The complex Myriopteris lendigera is composed of three species, M. lendigera, M. marsupianthes and M. mexicana, which are characterized by a high degree of morphological variation, making it a complex task to establish clear boundaries between these taxa. The objective of this study was to analyze the morphological and anatomical characteristics of this complex in order to define its taxonomic status. A total of 30 morphological and 12 anatomical characteristics were measured, both in botanical specimens collected in the field (in four Mexican entities) and in specimens from ten Mexican herbaria. With the data obtained, descriptive statistics were estimated and different analyses were performed: variance, clustering (CA), principal components (PCA), and discriminant (AD). The anatomical characteristics did not differ significantly among species, but the morphological ones did. The length of the petiole, width of the false indusium, length of the frond, and width of the second pinna, were the variables that allow differentiation among species. The percentage of variance explained by the data was high and related to the first two components (65.99%) in ACP or discriminant functions (100%) in AD. The Mahalonobis distances indicated that the variation in the selected characteristics is significant between the taxa. Based on these results and on the clustering of the taxa in ordination diagrams, it is suggested that M. lendigera, M. marsupianthes, and M. mexicana are valid species or defined entities, with unique qualitative and quantitative morphological features that enable their identification.