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Abstract The Nippostrongylinae is a group of strongylid nematodes that includes species typically associated with coprophagous mammals; in the New World, it is represented by 82 species within 11 genera. Two main morphological features, the synlophe and the caudal bursa, are used to evaluate the characteristics that allow identification and classification of the organisms in the taxon. However, the analysis of these characters often requires a partial or total destruction of specimens and therefore morphological variation is studied in only a very small subset of organisms per species. To evaluate the phylogenetic signal from these characteristics, we use genetic data to reconstruct the first phylogeny for the Nippostrongylinae using nuclear and mitochondrial genes and include representatives of the most common and diverse genera. The reconstructed phylogeny features five distinct clades and allows us to identify three non-monophyletic taxa includingCarolinensis, VexillataandHassalstrongylus. From these,Carolinensis s. l. is divided into four genera includingCarolinensis, Boreostrongylus, Neoboreostrongylusn. gen. andTepalcuaneman. gen.Stunkardionemais resurrected to includeVexillata noviberiaeandHassalstrongylusis divided into two, establishingLovostrongylusn. gen. to include species that are closely related toGuerrerostrongylusandTrichofreitasia. Organisms in these three genera feature a caudal arrangement of type 2-2-1. Furthermore, species inHassalstrongylus sensu strictoare more closely related to species inMalvinemaandStilestrongylus. Our results reveal the existence of an additional unnamed genus and underscore the usefulness of framing morphological characters in a comparative framework. A key for genera from the Americas is proposed.
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Phylogenetic revision of Dennstaedtioideae (Dennstaedtiaceae: Polypodiales) with description of Mucura , gen. nov.
Abstract We undertook a molecular phylogenetic revision of hayscented ferns (Dennstaedtiaceae: Dennstaedtioideae) using four plastid markers. Our sampling represents ca. 40% of the extant diversity and includes the type species for each of the relevant segregate genera. We coded 18 discrete morphological characters which we used to find diagnosable clades. We show that Dennstaedtia is polyphyletic, with the majority of species forming three morphologically distinct clades, but its type ( D. flaccida ) is nested within Microlepia . As such, we support the conservation of Dennstaedtia with a new type, D. dissecta . Following our results, we develop a classification of four genera: Dennstaedtia , Microlepia , Mucura (gen. nov.) and Sitobolium . Beyond the inclusion of D. flaccida , we propose to maintain Microlepia with its current circumscription. Except for a single adventive species in the Neotropics, Microlepia is a Paleotropical genus of about 60 species diagnosed by their distinctive perispore ornamentation of rodlets, and by petioles that lack epipetiolar buds. Mucura is a Neotropical genus of two species that differ from all other Dennstaedtiaceae by the combination of dichotomously branching rhizomes, petioles that lack epipetiolar buds, marginal sori with both abaxial and adaxial indusia, and trilete spores with a unique perispore ornamentation. As defined here, Dennstaedtia is a pantropical genus of about 55 species recognized by having unbranched rhizomes, petioles bearing epipetiolar buds, and by often bearing proliferous buds upon the leaves. Sitobolium is a small clade of ca. five species distinguished by their relatively small leaves that have elongate catenate hairs. These hairs often bear a capitate non‐glandular terminal cell. In support of our classification, we provide a key to the eleven genera of Dennstaedtiaceae, and for the four genera of Dennstaedtioideae we provide morphological and geographic synopses, a list of constituent species, and necessary new combinations.
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- Award ID(s):
- 2101884
- PAR ID:
- 10444714
- Date Published:
- Journal Name:
- TAXON
- Volume:
- 72
- Issue:
- 1
- ISSN:
- 0040-0262
- Page Range / eLocation ID:
- 20 to 46
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/tax.12858
