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Premise: Molecular studies based on chloroplast markers have questioned the monophyly of the fern genus Pecluma (Polypodioideae, Polypodiaceae), which has several species of Polypodium nested within it. We explored the delimitation of Pecluma and its biogeographic pattern by evaluating the phylogenetic position of four Polypodium species not sequenced thus far and integrating the first fossil evidence of Pecluma. Methods: Using herbarium material, we applied a genome‐skimming approach to obtain a phylogenetic hypothesis of Polypodioideae; assessed the combination of character states observed in the fossil from Miocene Dominican amber using a previously published phylogeny of Polypodioideae based on four plastid markers as framework; calculated divergence times; and conducted an ancestral area estimation. Results: Within Polypodioideae, Pecluma was recovered as sister to Phlebodium. Three of the newly sequenced species—Polypodium otites, P. pinnatissimum, and P. ursipes—were recovered with maximum support within the Pecluma clade, whereas P. christensenii remained within Polypodium. The closest combination of character states of the fossil was found within Pecluma. Our biogeographic analyses suggest an Eocene origin of the genus in South America, with several subsequent Oligocene and Miocene colonization events to Mexico–Central America and to the West Indies. Conclusions: Although the circumscription of Pecluma is still challenging, our results elucidate the origin and age of the genus. The newly described fossil, Pecluma hispaniolae sp. nov., supports the hypothesis that the epiphytic communities of the Greater Antilles exhibit a constant generic composition since the Miocene. We propose new combinations (Pecluma otites, Pecluma pinnatissima, and Pecluma ursipes) to accommodate three species previously classified in Polypodium. [ABSTRACT FROM AUTHOR]

Myrsine cirrhosa Lorence & K.R.Wood (Primulaceae), a new single-island endemic shrub species from Kaua'i, Hawaiian Islands, is described and illustrated. Notes on its distribution, ecology and conservation status are included. The new species is known from an area with ca. 45 individuals, where it is restricted to the remote central windward region of Kaua'i in open bogs and along open windy ridges. Suggested IUCN Red List status is CR (Critically Endangered). It differs from its Kaua'i congeners by its longer petals and narrowly elliptic leaves with strongly undulate margins and tendril-like apex. Phylogenetic analysis using RADseq data supports the recognition of this new species. [ABSTRACT FROM AUTHOR]

AbstractApomixis, the reproduction via asexually formed seed, is taxonomically scattered in angiosperms. Here we review the major developmental pathways to apomixis and the occurrences on the level of orders and families. We provide surveys of large families for which occurrences and evolutionary pathways of apomixis are well documented (Poaceae, Ranunculaceae, Plumbaginaceae, Rosaceae, Brassicaceae, Rutaceae, and Asteraceae). Molecular phylogenetic, phylogenomic, and cytogenetic studies have confirmed that apomixis frequently arises in hybrids, with or without polyploidy. Multiple origins, different developmental pathways, and genetic/epigenetic control mechanisms confirm that apomixis is a derived trait. Pollen functions are in many taxa maintained for fertilization of polar nuclei and proper endosperm development, which allows also for maintenance of facultative sexuality and further intercrossing of lineages. This way, apomixis often results in huge and dynamic complexes of numerous hybrid genotypes and phenotypes with highly reticulate relationships. Such complexes are successful to establish in various habitats and geographical regions. Expression of apomixis appears to be in some genera influenced by environmental conditions. The diversity of evolutionary pathways is reflected in various, genus-wise taxonomic treatments. Future research is needed to understand the short-term evolutionary dynamics, the functional background for apomixis, and the long-term evolutionary fates of apomictic lineages. [ABSTRACT FROM AUTHOR]

Tetradium, a genus within Rutaceae, comprises nine species found in Eastern and Southeastern Asia, distinguished by their opposite pinnate leaves and apocarpous or subapocarpous gynoecium with follicular fruits. While Hartley's 1981 monograph provided foundational insights, a comprehensive phylogenetic analysis of the genus is lacking. Using next‐generation sequencing (NGS), this study aims to (i) establish an NGS molecular data set for Tetradium, (ii) elucidate interspecific relationships via the hybrid capture method and (iii) investigate the taxonomic status of Euodia meliifolia var. celebica. Our data set comprised 28 samples across nine species, sequenced using Illumina Miseq and Hiseq 4000 platforms, with downstream analyses conducted using the HybPhyloMaker pipeline and ASTRAL. Our findings revealed five main groups supported by both molecular and morphological data, highlighting changes in ovule number and seed functionality. Notably, the hybrid capture method proved invaluable for studying old herbarium specimens. Finally, taxonomic revisions were proposed, including the reclassification of E. meliifolia var. celebica as Tetradium celebicum, the fossil Euodia costata as Tetradium costatum, and the fossil Euodia lignata as Tetradium lignatum. An updated description for T. celebicum, supplemented by a specific identification key, is provided. [ABSTRACT FROM AUTHOR]

Myrsinecirrhosa Lorence & K.R.Wood (Primulaceae), a new single-island endemic shrub species from Kaua'i, Hawaiian Islands, is described and illustrated. Notes on its distribution, ecology and conservation status are included. The new species is known from an area with ca. 45 individuals, where it is restricted to the remote central windward region of Kaua'i in open bogs and along open windy ridges. Suggested IUCN Red List status is CR (Critically Endangered). It differs from its Kaua'i congeners by its longer petals and narrowly elliptic leaves with strongly undulate margins and tendril-like apex. Phylogenetic analysis using RADseq data supports the recognition of this new species., Competing Interests: The authors have declared that no competing interests exist., (David H. Lorence, Kenneth R. Wood, Marc S. Appelhans, Warren L. Wagner.)