Diadromie, dispersion et histoire évolutive des complexes "Caridina nilotica" et "Caridina weberi" (Crustacea - Decapoda - Atyidae) dans les systèmes insulaires de l’Indo-Pacifique

Abstract : Rivers of tropical islands harbor organisms that have developped a diadromous lifecycle, shared between a freshwater adult phase and a marine larval phase: amphidromy. Among these organisms, in the Indo-Pacific area are found shrimps of the genus Caridina H. Milne Edwards, 1837. With more than 300 described species it is the most speciose genus of the infra-order Caridea, with a most confused and complicated taxonomy. Within this genus, two species complexes are particularly well-represented in insular systems of the Indo-Pacific, the C. nilotica complex and the C. weberi complex. Thanks to the development of new sequencing techniques, new methods of integrative taxonomy appeared, allowing to resolve part of the taxonomic complexity of these taxa. The aim of the thesis was to apply an integrative taxonomy approach to species belonging to C. nilotica and C. weberi complexes in order to clarify their taxonomy and have a better understanding of their biology and provide tools to managers for establishing a better conservation of these species and their environments. After showing that some morphological characters traditionally used to describe species were influenced by the environment and so, highly variable, the integrative taxonomy was led on 92 species, allowing to obtain 1,682 sequences to which are added 32 complete and 97 partial mitochondrial genomes, highlighting 43 new species, some of them described during the thesis. Phylogenetic relationships among the species of the two complexes were reconstructed from a large molecular dataset, allowing to show that the complexes are monophyletic groups, with habitat differences. Finally, the feasibility of a sclerochronological study of amphidromy in a species of the C. weberi complex (C. multidentata) was tested on the eyestalk cuticle, with a study of the ultrastructure of the cuticle, described for the first time in this species.
Complete list of metadatas

Cited literature [784 references]  Display  Hide  Download

https://tel.archives-ouvertes.fr/tel-02314618
Contributor : Abes Star <>
Submitted on : Wednesday, October 16, 2019 - 5:34:09 PM
Last modification on : Thursday, October 17, 2019 - 1:27:56 AM

File

VA_SEIZILLES_Valentin_12102018...
Version validated by the jury (STAR)

Identifiers

  • HAL Id : tel-02314618, version 2

Citation

Valentin De Mazancourt. Diadromie, dispersion et histoire évolutive des complexes "Caridina nilotica" et "Caridina weberi" (Crustacea - Decapoda - Atyidae) dans les systèmes insulaires de l’Indo-Pacifique. Systématique, phylogénie et taxonomie. Museum national d'histoire naturelle - MNHN PARIS, 2018. Français. ⟨NNT : 2018MNHN0021⟩. ⟨tel-02314618v2⟩

Share

Metrics

Record views

130

Files downloads

10