The production of pentabromopseudilin and related brominated compounds by
- NSF-PAR ID:
- 10461130
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- Environmental Microbiology
- Volume:
- 21
- Issue:
- 5
- ISSN:
- 1462-2912
- Page Range / eLocation ID:
- p. 1575-1585
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Nylanderia (Emery) is one of the world's most diverse ant genera, with 123 described species worldwide and hundreds more undescribed. Fifteen globetrotting or invasive species have widespread distributions and are often encountered outside their native ranges. A molecular approach to understanding the evolutionary history and to revision ofNylanderia taxonomy is needed because historical efforts based on morphology have proven insufficient to define major lineages and delimit species boundaries, especially where adventive species are concerned. To address these problems, we generated the first genus‐wide genomic dataset ofNylanderia using ultraconserved elements (UCEs) to resolve the phylogeny of major lineages, determine the age and origin of the genus, and describe global biogeographical patterns. Sampling from seven biogeographical regions revealed a Southeast Asian origin ofNylanderia in the mid‐Eocene and four distinct biogeographical clades in the Nearctic, the Neotropics, the Afrotropics/Malagasy region, and Australasia. The Nearctic and Neotropical clades are distantly related, indicating two separate dispersal events to the Americas between the late Oligocene and early Miocene. We also addressed the problem of misidentification that has characterized species‐level taxonomy inNylanderia as a result of limited morphological variation in the worker caste by evaluating the integrity of species boundaries in six of the most widespreadNylanderia species. We sampled across ranges of species in theN. bourbonica complex (N. bourbonica (Forel) +N. vaga (Forel)), the complex (N. fulva (Mayr) +N. fulva N. pubens (Forel)), and the complex (N. guatemalensis (Forel) +N. guatemalensis N. steinheili (Forel)) to clarify their phylogenetic placement. Deep splits within these complexes suggest that some species names – specificallyN. bourbonica and – each are applied to multiple cryptic species. In exhaustively samplingN. guatemalensis Nylanderia diversity in the West Indies, a ‘hot spot’ for invasive taxa, we found five adventive species among 22 in the region; many remain morphologically indistinguishable from one another, despite being distantly related. We stress that overcoming the taxonomic impediment through the use of molecular phylogeny and revisionary study is essential for conservation and invasive species management. -
Abstract Phylogenetic studies of
Carex L. (Cyperaceae) have consistently demonstrated that most subgenera and sections are para‐ or polyphyletic. Yet, taxonomists continue to use subgenera and sections inCarex classification. Why? The GlobalCarex Group (GCG) here takes the position that the historical and continued use of subgenera and sections serves to (i) organize our understanding of lineages inCarex , (ii) create an identification mechanism to break the ~2000 species ofCarex into manageable groups and stimulate its study, and (iii) provide a framework to recognize morphologically diagnosable lineages withinCarex . Unfortunately, the current understanding of phylogenetic relationships inCarex is not yet sufficient for a global reclassification of the genus within a Linnean infrageneric (sectional) framework. Rather than leavingCarex classification in its current state, which is misleading and confusing, we here take the intermediate steps of implementing the recently revised subgeneric classification and using a combination of informally named clades and formally named sections to reflect the current state of our knowledge. This hybrid classification framework is presented in an order corresponding to a linear arrangement of the clades on a ladderized phylogeny, largely based on the recent phylogenies published by the GCG. It organizesCarex into six subgenera, which are, in turn, subdivided into 62 formally named Linnean sections plus 49 informal groups. This framework will serve as a roadmap for research onCarex phylogeny, enabling further development of a complete reclassification by presenting relevant morphological and geographical information on clades where possible and standardizing the use of formal sectional names. -
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