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The type of the xeniid soft coral Sansibia flava (May, 1898) is re-described for the first time and its morphological diagnosis is presented. A subsequent integrated analysis of molecular and morphological characters of related Xeniidae, including species indigenous to the Indo-Pacific Ocean and invasive in the Atlantic (Brazil), led to the description of a new Sansibia species, as well as two new genera comprising an additional three new species. All of these taxa are encrusting, with polyps arising directly from a spreading basal membrane. Molecular phylogenetic analyses show that these genera are not sister taxa, thus further emphasizing the remarkable phylogenetic diversity of xeniids with such a growth form. The sclerites of all species are uniformly ellipsoid platelets, abundant throughout the colony. The species exhibit restricted, non-overlapping geographic ranges, with distinct genotypes (molecular operational taxonomic units) found in different marine realms. The results emphasize the importance of re-examination of original old type material while applying molecular phylogenetic analyses in order to delineate species boundaries and to recognize biodiversity patterns.
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Botryandromyces, a morphology-based genus concept scrutinized by molecular data
Abstract Laboulbeniales(Ascomycota) are an order of understudied, biotrophic microfungi uniquely associated with arthropods. More than 2300 species are described but only a fraction of those have been sequenced. Molecular studies have shown that cryptic diversity and phenotypic plasticity are present within theLaboulbeniales. Thus far, all of the 146 genera described inLaboulbenialeshave been based on morphological characteristics; features commonly used to delineate genera are the organization of receptacle cells and the number of perithecial outer wall cells. The genusBotryandromyceswas erected to accommodate two species,B. heteroceriandB. ornatus(type), which share similar morphological characteristics and are different from other genera in their number of perithecial outer wall cells. Here, we generated sequences of multiple loci (18S, ITS, and 28S) ofB. heteroceriand severalLaboulbeniaspecies. Our phylogenetic analyses retrievedBotryandromyceswithinLaboulbeniawith high support. The twoBotryandromycesspecies are similar to relatedLaboulbeniaspecies in their upper receptacle (i.e., cells IV and V). We propose to transferBotryandromyces ornatusandB. heteroceritoLaboulbeniaasL. heteroceriandL. maireinom. nov., respectively, due to a complicated taxonomic history. These results advocate the use of molecular data and the necessity of an integrative taxonomy approach in the study ofLaboulbenialesnot only to delineate species, but also to investigate relationships among species, genera, and higher taxa as well as to understand the evolution of morphology in this group of fungi.
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- Award ID(s):
- 2127290
- PAR ID:
- 10473858
- Publisher / Repository:
- Springer Science + Business Media
- Date Published:
- Journal Name:
- Mycological Progress
- Volume:
- 22
- Issue:
- 12
- ISSN:
- 1617-416X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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