cpDNA supports the identification of the major lineages of American Blechnum (Blechnaceae, Polypodiopsida) established by morphology

Abstract

International audienceBlechnaceae is an important leptosporangiate family (9-10 genera, about 250 species). It is monophyletic and distributed mainly in tropical America and Australasia. Among the species 80% belong to Blechnum, a genus with a very complex taxonomy and uncertain internal relationships. In terms of American diversity, the results of morphological studies have arrived at 8 informal groups. Molecular works on this genus are scarce, and there is no information for the majority of American species. The main objective of this work was to evaluate whether the groups proposed to organise the diversity of American of Blechnum are consistent with a molecular analysis. We sequenced 2 chloroplastic regions from species representing all of the groups. In our molecular analysis most of the informal groups were maintained as well supported clades. Only 2 species, B. brasiliense and B. spicant, appear to be isolated from their alleged relatives. Combining our molecular results with previous morphological knowledge, we propose the recognition of 4 lineages: 1) B. serrulatum , 2) B. spicant, and 3) core Blechnum, which represents a large clade that can be divided into core Blechnum I (arborescent species, cordatoids, and B. brasiliense) and core Blechnum II (epiphytic species and herbaceous terrestrials, both monomorphic and dimorphic groups)

Profundizando en la evolución de los helechos: un enfoque mecanicista a los principales conceptos y técnicas de estudio

“…This is quite far from truth, as phylogenetics confirm, not infrequently, some of the major results previously proposed by morphological and paleobotanical data , Gabriel y Galán et al 2013. However, at the same time it is obvious that molecular techniques have allowed a very much better comprehension of taxa relationships, not only within families and genera, but also contributing novel findings at the higher levels (Hasebe et al 1994, Pryer et al 2004, Schuettpelz & Pryer 2007.…”

Molecular phylogeny of the fern family Blechnaceae (Polypodiales) with a revised genus‐level treatment

“…Our results are based on the largest data set thus far compiled for the family, with a sampling of the two main diversity centres: Neotropics and Australasia/Oceania. With the inclusion of a large neotropical sampling (about 80% of total species), we were able to expand on previous phylogenies (Gabriel y Galán et al., ; Perrie et al., ). Increased sampling (about 60% of species in the family) made it possible to address critical unresolved issues regarding generic circumscription in Blechnaceae (Perrie et al., ).…”

“…Gabriel y Galán et al. (), using a relatively small data set (18 species), showed incongruence between the taxonomy adopted by Tryon and Tryon () and molecular data. In a larger phylogenetic analysis, incorporating 113 species, Perrie et al.…”

“…Gabriel y Galán et al. () did not include Australasian species in their analysis, and Perrie et al. () had only a small sampling of neotropical and African/Madagascan species.…”

New combinations in Struthiopteris spicant for the European flora

“…During the last decade, evidence has been accumulating about the polyphyletism within Blechnum Linnaeus (1753: 1077) (e.g. Shepherd et al 2007, Rothfels et al 2012, Gabriel y Galán et al 2013, Perrie et al 2014. Recent molecular studies (Gasper et al 2016a) lead to an updated classification attempting to put morphological characters into a natural, phylogenetic relation (Gasper et al 2016b).…”