Cryptic diversity and species boundaries within the Paragalago zanzibaricus species complex

Rhizobia supply legumes with fixed nitrogen using a set of symbiosis genes. These can cross rhizobium species boundaries, but it is unclear how many other genes show similar mobility. Here, we investigate inter-species introgression using de novo assembly of 196 Rhizobium leguminosarum sv. trifolii genomes. The 196 strains constituted a five-species complex, and we calculated introgression scores based on gene-tree traversal to identify 171 genes that frequently cross species boundaries. Rather than relying on the gene order of a single reference strain, we clustered the introgressing genes into four blocks based on population structure-corrected linkage disequilibrium patterns. The two largest blocks comprised 125 genes and included the symbiosis genes, a smaller block contained 43 mainly chromosomal genes, and the last block consisted of three genes with variable genomic location. All introgression events were likely mediated by conjugation, but only the genes in the symbiosis linkage blocks displayed overrepresentation of distinct, high-frequency haplotypes. The three genes in the last block were core genes essential for symbiosis that had, in some cases, been mobilized on symbiosis plasmids. Inter-species introgression is thus not limited to symbiosis genes and plasmids, but other cases are infrequent and show distinct selection signatures.

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Untangling the Lactifluus clarkeae - Lf. flocktoniae (Russulaceae) species complex in Australasia

Persoonia - Molecular Phylogeny and Evolution of Fungi ◽

10.3767/persoonia.2021.47.01 ◽

2021 ◽

Author(s):

T. Lebel ◽

J. Douch ◽

L. Tegart ◽

L. Vaughan ◽

J.A. Cooper ◽

...

Keyword(s):

New Species ◽

New Zealand ◽

Species Complex ◽

Molecular Data ◽

Habitat Associations ◽

Species Level ◽

Range Extension ◽

Cryptic Diversity ◽

Identification Of Species

The Lactifluus clarkeae complex is a commonly observed, generally brightly coloured, group of mushrooms that are usually associated with Nothofagus or Myrtaceous hosts in Australia and New Zealand. For this study collections labelled as ‘Lactarius clarkeae’, ‘Russula flocktoniae’ and ‘Lactarius subclarkeae’ were examined morpiperatphologically and molecularly. Analyses of molecular data showed a high cryptic diversity, with sequences scattered across 11 clades in three subgenera within Lactifluus, and a single collection in Russula. We select epitypes to anchor the currently accepted concepts of Lf. clarkeae s.str. and Lf. flocktoniae s.str. The name Lf. subclarkeae could not be applied to any of the collections examined, as none had a lamprotrichoderm pileipellis. Lactifluus clarkeae var. aurantioruber is raised to species level, and six new species are described, three in subg. Lactifluus: Lf. jetiae, Lf. pagodicystidiatus, and Lf. rugulostipitatus, and three in subg. Gymnocarpi: Lf. albens, Lf. psammophilus, and Lf. pseudoflocktoniae. A new collection of Lf. russulisporus provides a significant range extension for the species. Untangling this complex will enable better identification of species and increase understanding of diversity and specific habitat associations of macrofungi.

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Species delimitation within the Glaucidium brodiei owlet complex using bioacoustic tools

Avian Research ◽

10.1186/s40657-019-0175-4 ◽

2019 ◽

Vol 10 (1) ◽

Cited By ~ 2

Author(s):

Chyi Yin Gwee ◽

James A. Eaton ◽

Elize Y. X. Ng ◽

Frank E. Rheindt

Keyword(s):

Natural History ◽

Species Delimitation ◽

Species Complex ◽

Principal Component ◽

Single Species ◽

Natural History Museum ◽

Species Boundaries ◽

Test Species ◽

History Museum ◽

Plumage Colouration

Abstract Background The taxonomy of the Collared Owlet (Glaucidium brodiei) species complex is confused owing to great individual variation in plumage colouration seemingly unrelated to their distribution. Although generally recognised as a single species, vocal differences among the subspecies have been noted by field recordists. However, there is no study assessing the vocal differences among these four subspecies. Methods We obtained 76 sound recordings of the G. brodiei species complex comprising all four subspecies. We conducted bioacoustic examinations using principal component analysis and the Isler criterion to quantitatively test species boundaries within the G. brodiei complex. In addition, we compared plumage colouration among 13 specimens of the G. brodiei complex deposited at the Natural History Museum at Tring, UK and the Lee Kong Chian Natural History Museum, Singapore to ascertain the presence of plumage differences across taxa. Results We found the Bornean and Sumatran populations vocally similar to each other, but distinctly different from the mainland and Taiwan populations. The vocal pattern seems to corroborate plumage distinctions in the colouration of neck collars: the Bornean and Sumatran taxa share a white neck collar, whereas the continental and Taiwan taxa share a rufous neck collar. Conclusions We propose the taxonomic elevation of the Sumatran and Bornean populations to species level as Sunda Owlet G. sylvaticum, with one subspecies on Sumatra (G. s. sylvaticum) and Borneo (G. s. borneense) each. Our study corroborates the importance of bioacoustics in ascertaining species boundaries in non-passerines, and emphasises the significance of incorporating multiple species delimitation approaches when making taxonomic decisions.

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