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Geometric morphometric on a new species of Trichodinidae. A tool to discriminate trichodinid species combined with traditional morphology and molecular analysis.

ABSTRACT: This study reports a new Trichodinidae, Trichodina bellottii n. sp., parasitizing the pearly fish Austrolebias bellottii from Buenos Aires, Argentina. Its small subunit ribosomal ribonucleic acid (SSU rDNA) was sequenced for the first time. Based on the results from morphological identification, SSU rDNA sequencing, and Elliptical Fourier analysis, the new species was identified and compared with similar species. Phylogenetic analysis revealed that the genetic distances among the new species and similar species reached interspecific levels, furthermore, the phylogenetic study also validated the identification of T. bellottii n. sp. and its placement in the genus Trichodina. To be able to quantitatively describe the differences in shapes with similar species, this study used the elliptic Fourier analysis by first time in this genus.

SUBMITTER: Marcotegui PS

PROVIDER: S-EPMC6032030 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Geometric morphometric on a new species of Trichodinidae. A tool to discriminate trichodinid species combined with traditional morphology and molecular analysis.

Marcotegui Paula S PS Montes Martin M MM Barneche Jorge J Ferrari Walter W Martorelli Sergio S

International journal for parasitology. Parasites and wildlife 20180619 2

This study reports a new Trichodinidae, <i>Trichodina bellottii</i> n. sp., parasitizing the pearly fish <i>Austrolebias bellottii</i> from Buenos Aires, Argentina. Its small subunit ribosomal ribonucleic acid (SSU rDNA) was sequenced for the first time. Based on the results from morphological identification, SSU rDNA sequencing, and Elliptical Fourier analysis, the new species was identified and compared with similar species. Phylogenetic analysis revealed that the genetic distances among the n ...[more]

PMID: 29988856

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Project description:Morphological data are a conduit for the recognition and description of species, and their acquisition has recently been broadened by geometric morphometric (GM) approaches that co-join the collection of digital data with exploratory 'big data' analytics. We employed this approach to dissect the Western Rattlesnake (Crotalus viridis) species-complex in North America, currently partitioned by mitochondrial (mt)DNA analyses into eastern and western lineages (two and seven subspecies, respectively). The GM data (i.e., 33 dorsal and 50 lateral head landmarks) were gleaned from 2,824 individuals located in 10 museum collections. We also downloaded and concatenated sequences for six mtDNA genes from the NCBI GenBank database. GM analyses revealed significant head shape differences attributable to size and subspecies-designation (but not their interactions). Pairwise shape distances among subspecies were significantly greater than those derived from ancestral character states via squared-change parsimony, with the greatest differences separating those most closely related. This, in turn, suggests the potential for historic character displacement as a diversifying force in the complex. All subspecies, save one, were significantly differentiated in a Bayesian discriminant function analysis (DFA), regardless of whether our priors were uniform or informative (i.e., mtDNA data). Finally, shape differences among sister-clades were significantly greater than expected by chance alone under a Brownian model of evolution, promoting the hypothesis that selection rather than drift was the driving force in the evolution of the complex. Lastly, we combine head shape and mtDNA data so as to derived an integrative taxonomy that produced robust boundaries for six OTUs (operational taxonomic units) of the C. viridis complex. We suggest these boundaries are concomitant with species-status and subsequently provide a relevant nomenclature for its recognition and representation.

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Dataset Information

Geometric morphometric on a new species of Trichodinidae. A tool to discriminate trichodinid species combined with traditional morphology and molecular analysis.

Publications

Geometric morphometric on a new species of Trichodinidae. A tool to discriminate trichodinid species combined with traditional morphology and molecular analysis.

Similar Datasets

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