Combined Phylogenetic Analysis of the Subclass Marchantiidae (Marchantiophyta): towards a robustly diagnosed classification

JORGE R. FLORES; SANTIAGO A. CATALANO ; JESÚS MUÑOZ; GUILLERMO M. SUÁREZ

CLADISTICS (PRINT)

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2017

0748-3007

The most extensive combined phylogenetic analyses of the subclass Marchantiidae was conducted on the basis of morphological and molecular data. The morphological data comprised 126 characters and 56 species. Taxonomic samplingincluded 35 ingroup species with all genera and orders of Marchantiidae sampled and 21 outgroup species with two genera of Blasiidae (Marchantiopsida), 15 species of Jungermanniopsida (the three subclasses represented) and the three genera ofHaplomitriopsida. Takakia ceratophylla (Bryophyta) was employed to root the trees.Character sampling involved 92 gametophytic traits and 34 sporophytic traits. Ten continuous characters were included in a liverworts phylogeny for the first time.Molecular data included 11 molecular markers: three mitochondrial genes (nad1,nad5, rps3), seven chloroplast regions (atpB, psbT-psbH, rbcL, ITS, rpoC1, rps4, psbA)and one nuclear ribosomal gene (26S). Searches were performed under extended implied weighting, weighting the character blocks against the average homoplasy.Clades stability was assessed across three additional weighting schemes (implyweighting corrected for missing entries, standard implied weighting and equalweighting) in three datasets (molecular, morphological and combined). Thecontribution from different biological phases regarding node recovery and diagnosis was evaluated. Our results agree with many of the previous studies while cast doubt in some relationships, mainly at the family and inter-family level. The combined analyses underlined the fact that, by combining data, taxonomic enhancements could be achieved regarding taxa delimitation and diagnosis quality. Many scarcely supported clades of previous molecular studies were improved by the addition of morphological data. The general idea that morphology may render spurious or low-quality results in this taxonomic group is challenged. The morphological trends previously proposed are re-evaluated in light of the new phylogenetic scheme.Page 2 of 56Cladistics