TY - JOUR

T1 - Ribosomal RNA genes challenge the monophyly of the Hyalospheniidae (Amoebozoa: Arcellinida).

AU - Lara, Enrique

AU - Heger, Thierry J

AU - Ekelund, Flemming

AU - Lamentowicz, Mariusz

AU - Mitchell, Edward A D

N1 - Keywords: Amoeba; Animals; Bryophyta; DNA, Protozoan; DNA, Ribosomal; Evolution, Molecular; Microscopy, Electron, Scanning; Molecular Sequence Data; Phylogeny; RNA, Ribosomal, 18S; Sequence Alignment; Sequence Analysis, DNA

PY - 2008

Y1 - 2008

N2 - To date only five partial and two complete SSU rRNA gene sequences are available for the lobose testate amoebae (Arcellinida). Consequently, the phylogenetic relationships among taxa and the definition of species are still largely dependant on morphological characters of uncertain value, which causes confusion in the phylogeny, taxonomy and the debate on cosmopolitanism of free-living protists. Here we present a SSU rRNA-based phylogeny of the Hyalospheniidae including the most common species. Similar to the filose testate amoebae of the order Euglyphida the most basal clades have a terminal aperture; the ventral position of the pseudostome appears to be a derived character. Family Hyalospheniidae appears paraphyletic and is separated into three clades: (1) Heleopera sphagni, (2) Heleopera rosea and Argynnia dentistoma and (3) the rest of the species from genera Apodera, Hyalosphenia, Porosia and Nebela. Our data support the validity of morphological characters used to define species among the Hyalospheniidae and even suggest that taxa described as varieties may deserve the rank of species (e.g. N. penardiana var. minor). Finally our results suggest that the genera Hyalosphenia and Nebela are paraphyletic, and that Porosia bigibbosa branches inside the main Nebela clade.

AB - To date only five partial and two complete SSU rRNA gene sequences are available for the lobose testate amoebae (Arcellinida). Consequently, the phylogenetic relationships among taxa and the definition of species are still largely dependant on morphological characters of uncertain value, which causes confusion in the phylogeny, taxonomy and the debate on cosmopolitanism of free-living protists. Here we present a SSU rRNA-based phylogeny of the Hyalospheniidae including the most common species. Similar to the filose testate amoebae of the order Euglyphida the most basal clades have a terminal aperture; the ventral position of the pseudostome appears to be a derived character. Family Hyalospheniidae appears paraphyletic and is separated into three clades: (1) Heleopera sphagni, (2) Heleopera rosea and Argynnia dentistoma and (3) the rest of the species from genera Apodera, Hyalosphenia, Porosia and Nebela. Our data support the validity of morphological characters used to define species among the Hyalospheniidae and even suggest that taxa described as varieties may deserve the rank of species (e.g. N. penardiana var. minor). Finally our results suggest that the genera Hyalosphenia and Nebela are paraphyletic, and that Porosia bigibbosa branches inside the main Nebela clade.

U2 - 10.1016/j.protis.2007.09.003

DO - 10.1016/j.protis.2007.09.003

M3 - Journal article

C2 - 18023614

VL - 159

SP - 165

EP - 176

JO - Protist

JF - Protist

SN - 1434-4610

IS - 2

ER -