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Abstract Selection on spore dispersal mechanisms in mosses is thought to shape the transformation of the sporophyte. The majority of extant mosses develop a sporangium that dehisces through the loss of an operculum, and regulates spore release through the movement of articulate teeth, the peristome, lining the capsule mouth. Such complexity was acquired by the Mesozoic Era, but was lost in some groups during subsequent diversification events, challenging the resolution of the affinities for taxa with reduced architectures. The Funariaceae are a cosmopolitan and diverse lineage of mostly annual mosses, and exhibit variable sporophyte complexities, spanning from long, exerted, operculate capsules with two rings of well‐developed teeth, to capsules immersed among maternal leaves, lacking a differentiated line of dehiscence (i.e., inoperculate) and without peristomes. The family underwent a rapid diversification, and the relationships of taxa with reduced sporophytes remain ambiguous. Here, we infer the relationships of five taxa with highly reduced sporophytes based on 648 nuclear loci (exons complemented by their flanking regions), based on inferences from concatenated data and concordance analysis of single gene trees.Physcomitrellopsisis resolved as nested within one clade ofEntosthodon.Physcomitrellas. l., is resolved as a polyphyletic assemblage and, along with its putative relativeAphanorrhegma, nested withinPhyscomitrium. We propose a new monophyletic delineation ofPhyscomitrium, which accommodates species ofPhyscomitrellaandAphanorrhegma. The monophyly ofPhyscomitriums. l. is supported by a small plurality of exons, but a majority of trees inferred from exons and their adjacent non‐coding regions.
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Frequent allopolyploidy with distant progenitors in the moss genera Physcomitrium and Entosthodon (Funariaceae) identified via subgenome phasing of targeted nuclear genes
Abstract Allopolyploids represent a new frontier in species discovery among embryophytes. Within mosses, allopolyploid discovery is challenged by low morphological complexity. The rapid expansion of sequencing approaches in addition to computational developments to identifying genome merger and whole-genome duplication using variation among nuclear loci representing homeologs has allowed for increased allopolyploid discovery among mosses. Here, we test a novel approach to phasing homeologs within loci and phasing loci across subgenomes, or subgenome assignment, called Homologizer, in the family Funariaceae. We confirm the intergeneric hybrid nature of Entosthodon hungaricus, and the allopolyploid origin of Physcomitrium eurystomum and one population of Physcomitrium collenchymatum. We also reveal that hybridization gave rise to Physcomitrium immersum, as well as to yet unrecognized lineages sharing the phenotype of Physcomitrium pyriforme and Physcomitrium sphaericum. Our findings demonstrate the utility of our approach when working with polyploid genomes, and its value in identifying progenitor species using target capture data.
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- PAR ID:
- 10477422
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Evolution
- Volume:
- 77
- Issue:
- 12
- ISSN:
- 0014-3820
- Format(s):
- Medium: X Size: p. 2561-2575
- Size(s):
- p. 2561-2575
- Sponsoring Org:
- National Science Foundation
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