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Abstract Traits of the spore‐bearing generation have historically provided the basis for systematic concepts across the phylogenetic spectrum and depth of mosses. Whether taxa characterized by a simple sporophytic architecture are closely related or emerged from independent reduction is often ambiguous. Phylogenomic inferences in the Funariaceae, which hold the model taxonPhyscomitrium patens, revealed that several such shifts in sporophyte complexity occurred, and mostly within theEntosthodon‐Physcomitriumcomplex. Here, we report the rediscovery of the monospecific, Himalayan endemic generaBrachymeniopsisandClavitheca, after nearly 100 years and 40 years since their respective descriptions. The genera are characterized by, among other traits, their short sporophytes lacking the sporangial peristome teeth controlling spore dispersal. Phylogenomic inferences reveal thatBrachymeniopsis gymnostomaarose within the clade ofEntosthodons.str., a genus with typically long‐exserted capsules. We therefore propose to transferB. gymnostomato the genusEntosthodon, asE. gymnostomuscomb. nov.Furthermore,Clavitheca poeltii, the sole species of the genus, is morphologically highly similar toE. gymnostomus, and should also be transferred toEntosthodon, but is retained as a distinct taxon,E. poeltiicomb. nov., until additional populations allow for testing the robustness of the observed divergence in costa and seta length between the Nepalese and Chinese populations.
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Phylogenomic delineation of Physcomitrium (Bryophyta: Funariaceae) based on targeted sequencing of nuclear exons and their flanking regions rejects the retention of Physcomitrella , Physcomitridium and Aphanorrhegma
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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- PAR ID:
- 10106933
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Journal of Systematics and Evolution
- Volume:
- 57
- Issue:
- 4
- ISSN:
- 1674-4918
- Page Range / eLocation ID:
- p. 404-417
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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