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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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Enigmas no longer: using ultraconserved elements to place several unusual hawk taxa and address the non-monophyly of the genus Accipiter (Accipitriformes: Accipitridae)
Abstract Hawks, eagles, and their relatives (Accipitriformes: Accipitridae) are a diverse and charismatic clade of modern birds, with many members that are instantly recognized by the general public. However, surprisingly little is known about the relationships among genera within Accipitridae, and several studies have suggested that some genera (in particular, the megadiverse genus Accipiter) are not monophyletic. Here, we combine a large new dataset obtained from ultraconserved elements, generated from whole genome sequencing of 134 species, with publicly available legacy markers (i.e. a suite of commonly sequenced mitochondrial and nuclear genes) to infer a well-supported, time-calibrated phylogeny of 237 extant or recently extinct species. Our densely sampled phylogeny, which includes 90% of recognized species, confirms the non-monophyly of Accipiter and provides a sufficient basis to revise the genus-level taxonomy, such that all genera in Accipitridae represent monophyletic groups.
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- Award ID(s):
- 2203228
- PAR ID:
- 10496538
- Publisher / Repository:
- Oxford University Press
- Date Published:
- Journal Name:
- Biological Journal of the Linnean Society
- Volume:
- 144
- Issue:
- 2
- ISSN:
- 0024-4066
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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