Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Phylogeny of Chaetonotidae (Gastrotricha) inferred from nuclear and mitochondrial genes
Stockholm University, Faculty of Science, Department of Zoology, Systematic Zoology.ORCID iD: 0000-0001-7151-5915
Stockholm University, Faculty of Science, Department of Zoology, Systematic Zoology.
(English)Manuscript (preprint) (Other academic)
Abstract [en]

Chaetonotidae is the largest family within Gastrotricha with almost 400 nominal species, represented in both freshwater and marine habitats. The group is probably non-monophyletic and suffers from a troubled taxonomy. Current classification is to a great extent based on shape and distribution of cuticular structures, characters that are highly variable. We present the most densely sampled molecular study so far where 17 out of 31 genera belonging to Chaetonotida are represented. Bayesian and maximum likelihood approaches based on 18S rDNA, 28S rDNA and COI mtDNA are used to reconstruct relationships within Chaetonotidae. The use of cuticular structures for supra-specific classification within the group is evaluated and the question of dispersal between marine and freshwater habitats is addressed. Moreover the subgeneric classification of Chaetonotus is tested in a phylogenetic context. Our results show high support for a clade containing Dasydytidae nested within Chaetonotidae. Within this clade only 3 genera are monophyletic following current classification. Genera containing both marine and freshwater species never form monophyletic clades and group with other species according to habitat. Marine members of Aspidiophorus appear to be the sister group of all other Chaetonotidae and Dasydytidae, indicating a marine origin of the clade. Halichaetonotus and marine Heterolepidoderma form a monophyletic group in a sister group relationship to freshwater species, pointing towards a secondary invasion to marine environments of these taxa. Our study shows the problems of current classification based on cuticular structures, characters that show homoplasy for deeper relationships.

Keyword [en]
Paucitubulatina, Xenotrichulidae, Chaetonotus, Bayesian, Maximum likelihood, 18S rDNA, 28S rDNA, COI mtDNA
National Category
Zoology
Research subject
Systematic Zoology
Identifiers
URN: urn:nbn:se:su:diva-63551OAI: oai:DiVA.org:su-63551DiVA: diva2:450814
Projects
Gastrotricha of Sweden
Available from: 2011-10-22 Created: 2011-10-22 Last updated: 2014-10-28Bibliographically approved
In thesis
1. Gastrotricha of Sweden - Biodiversity and Phylogeny
Open this publication in new window or tab >>Gastrotricha of Sweden - Biodiversity and Phylogeny
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Gastrotricha are small aquatic invertebrates with approximately 770 known species. The group has a cosmopolitan distribution and is currently classified into two orders, Chaetonotida and Macrodasyida. The gastrotrich fauna of Sweden is poorly known: a couple of years ago only 29 species had been reported. In Paper I, III, and IV, 5 freshwater species new to science are described. In total 56 species have been recorded for the first time in Sweden during the course of this thesis. Common species with a cosmopolitan distribution, e. g. Chaetonotus hystrix and Lepidodermella squamata, as well as rarer species, e. g. Haltidytes crassus, Ichthydium diacanthum and Stylochaeta scirtetica, are reported. In Paper II molecular data is used to infer phylogenetic relationships within the morphologically very diverse marine family Thaumastodermatidae (Macrodasyida). Results give high support for monophyly of Thaumastodermatidae and also the subfamilies Diplodasyinae and Thaumastoder­matinae. In Paper III the hypothesis of cryptic speciation is tested in widely distributed freshwater gastrotrichs. Heterolepidoderma ocellatum f. sphagnophilum is raised to species under the name H. acidophilum n. sp. The results indicate that L. squamata may be a complex of at least two species. In Paper III and V the phylogeny of Chaetonotidae (Chaetonotida), the largest family within Gastrotricha, is inferred. The group suffers from a troubled taxonomy and is hypothesized to be non-monophyletic. Results show that members of Dasydytidae are nested within the group. Since only 3 of 17 sampled genera are monophyletic, it is hypothesized that the cuticular structures used in current classification do not reflect phylogenetic relationships. The phylogenetic hypothesis generated in Paper V indicates a marine origin of the predominantly limnic Chaetonotidae with a subsequent secondary invasion to marine environments of some taxa.

Place, publisher, year, edition, pages
Stockholm: Department of Zoology, Stockholm University, 2011. 34 p.
Keyword
taxonomy, systematics, phylogeny, new species, cryptic species, Chaetonotidae, Dasydytidae, Thaumastodermatidae
National Category
Biological Systematics
Research subject
Systematic Zoology
Identifiers
urn:nbn:se:su:diva-63590 (URN)978-91-7447-397-1 (ISBN)
Public defence
2011-12-16, Lilla hörsalen, Naturhistoriska riksmuseet, Frescativägen 40, Stockholm, 10:00 (English)
Opponent
Supervisors
Projects
Gastrotricha of Sweden
Note
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Accepted. Paper 5: Manuscript.Available from: 2011-11-24 Created: 2011-10-24 Last updated: 2014-10-28Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Kånneby, TobiasJondelius, Ulf
By organisation
Systematic Zoology
Zoology

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 172 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf