scholarly journals Isolates from ancient permafrost help to elucidate species boundaries in Acanthamoeba castellanii complex (Amoebozoa: Discosea)

2019 ◽  
Author(s):  
Stas Malavin ◽  
Lyubov Shmakova

AbstractAcanthamoeba castellanii species complex (genotype T4) comprises of more than ten species with unclear synonymy. Its molecular phylogeny has several conflicts with published morphological data. In this paper, we analyze morphometric traits and temperature preferences in six new strains belonging to A. castellanii complex isolated from Arctic permafrost in the framework of molecular phylogeny. This integrative approach allows us to cross-link genotypic and phenotypic variability and identify species-level boundaries inside the complex. We also analyze previously known and newly found discrepancies between the nuclear and mitochondrial gene-based phylogenies. We hypothesize that one reason for these discrepancies may be the intragenomic polymorphism of ribosomal RNA genes.

Zootaxa ◽  
2011 ◽  
Vol 2890 (1) ◽  
pp. 1 ◽  
Author(s):  
CHI-LI TSAI ◽  
CHUNG-CHENG LU ◽  
HSIAO-WEI KAO

Meghimatium is a group of terrestrial slugs distributed in Asia. 185 specimens were collected from Taiwan, China, Okinawa (Japan), Thailand and Malaysia. Phylogenetic analyses using concatenated DNA sequences of cytochrome C oxidase subunit I, 16S ribosomal RNA and nuclear 28S ribosomal RNA genes revealed that clades in the resulting molecular phylogeny of Meghimatium are largely congruent with taxa identified on the basis of their genitalia. Four monophyletic groups, i.e., the M. fruhstorferi, M. burchi, M. uniforme and M. striatum complexes, with moderate to strong statistical supports (86/53/0.98/66, 100/100/1.00/100, 100/100/1.00/100, 100/100/1.00/100) were identified. M. pictum is paraphyletic and is clustered with M. bilineatum to constitute an additional monophyletic group (100/100/1.00/100). Body size does not show an evolutionary trend either from small to large or vice versa, based on the phylogenetic tree. A new species, M. baoshanense sp. nov., is named based on the included specimens constituting a monophyletic group, its medium size (40.1–52.7 mm in body length) and its genitalia with 10–18 papillae at the lower end of the spermathecal duct where it connects to the uterus and vagina.


2020 ◽  
Vol 190 (2) ◽  
pp. 518-531 ◽  
Author(s):  
Ahmed J Saadi ◽  
Angus Davison ◽  
Christopher M Wade

Abstract We have undertaken a comprehensive molecular phylogenetic analysis of the Hygrophila based on 3112 sites of the large subunit and 5.8S ribosomal RNA genes. A clear basal division between Chilinoidea and Lymnaeoidea is observed. The monophyly of Acroloxidae, Lymnaeidae and Physidae is also well established. However, Planorbidae are not supported as a monophyletic group, because the Bulinidae cluster within Planorbidae. The Amphipepleinae within Lymnaeidae and both Planorbinae and Ancylinae within Planorbidae are strongly supported as monophyletic subfamilies. However, the Aplexinae within Physidae and the Lymnaeinae within Lymnaeidae are not recovered. A new taxonomic revision of the Hygrophila is proposed based on the findings of this molecular phylogeny, and the implications for the evolution of chirality are discussed.


1996 ◽  
Vol 89 (6) ◽  
pp. 788-803 ◽  
Author(s):  
Nicolas Chalwatzis ◽  
Jörg Hauf ◽  
Yves Van De Peer ◽  
Ragnar Kinzelbach ◽  
Friedrich K. Zimmermann

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Edoardo Massa ◽  
Roberto Guidetti ◽  
Michele Cesari ◽  
Lorena Rebecchi ◽  
K. Ingemar Jönsson

AbstractKristianstads Vattenrike Biosphere Reserve [KVBR] is a UNESCO designated area of Sweden possessing high biological value. Although several studies on tardigrades inhabiting Sweden have been performed, the KVBR area has been neglected. The current study investigates the tardigrade fauna of five areas of the biosphere reserve and includes 34 samples of different substrates analysed quantitatively and qualitatively. In total, 33 species of tardigrades were found in the samples, including 22 new records for the Skåne region, 15 new records for Sweden, and four species new to science. Mesobiotus emiliae sp. nov., Xerobiotus gretae sp. nov., Itaquascon magnussoni sp. nov., and Thulinius gustavi sp. nov. were described with an integrative approach (when possible) using morphological characters (light, electron scanning, and confocal laser scanning microscopies) and molecular markers (ITS2, 18S, 28S, cox1). A new protocol to increase morphological data was developed recovering mounted specimens within old slides for SEM analysis. Emended diagnoses for the genus Itaquascon and the transfer of Platicrista itaquasconoide to the genus Meplitumen are proposed. This study enriches the knowledge of the tardigrade biodiversity both within the KVBR and in Sweden and contributes to the rapidly increasing number of tardigrade species reported worldwide. The 33 species identified in the KVBR area represents 28% of all water bear species found in Sweden so far. The restricted study areas and limited number of samples collected suggests that the KVBR is very rich of tardigrades.


1987 ◽  
Vol 8 (1) ◽  
pp. 3-12 ◽  
Author(s):  
R. A. Jorgensen ◽  
R. E. Cuellar ◽  
W. F. Thompson ◽  
T. A. Kavanagh

Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1185
Author(s):  
Wenqian Wang ◽  
Huan Zhang ◽  
Jérôme Constant ◽  
Charles R. Bartlett ◽  
Daozheng Qin

The complete mitogenomes of nine fulgorid species were sequenced and annotated to explore their mitogenome diversity and the phylogenetics of Fulgoridae. All species are from China and belong to five genera: Dichoptera Spinola, 1839 (Dichoptera sp.); Neoalcathous Wang and Huang, 1989 (Neoalcathous huangshanana Wang and Huang, 1989); Limois Stål, 1863 (Limois sp.); Penthicodes Blanchard, 1840 (Penthicodes atomaria (Weber, 1801), Penthicodes caja (Walker, 1851), Penthicodes variegata (Guérin-Méneville, 1829)); Pyrops Spinola, 1839 (Pyrops clavatus (Westwood, 1839), Pyrops lathburii (Kirby, 1818), Pyrops spinolae (Westwood, 1842)). The nine mitogenomes were 15,803 to 16,510 bp in length with 13 protein-coding genes (PCGs), 22 transfer RNA genes (tRNAs), 2 ribosomal RNA genes (rRNAs) and a control region (A + T-rich region). Combined with previously reported fulgorid mitogenomes, all PCGs initiate with either the standard start codon of ATN or the nonstandard GTG. The TAA codon was used for termination more often than the TAG codon and the incomplete T codon. The nad1 and nad4 genes varied in length within the same genus. A high percentage of F residues were found in the nad4 and nad5 genes of all fulgorid mitogenomes. The DHU stem of trnV was absent in the mitogenomes of all fulgorids sequenced except Dichoptera sp. Moreover, in most fulgorid mitogenomes, the trnL2, trnR, and trnT genes had an unpaired base in the aminoacyl stem and trnS1 had an unpaired base in the anticodon stem. The similar tandem repeat regions of the control region were found in the same genus. Phylogenetic analyses were conducted based on 13 PCGs and two rRNA genes from 53 species of Fulgoroidea and seven outgroups. The Bayesian inference and maximum likelihood trees had a similar topological structure. The major results show that Fulgoroidea was divided into two groups: Delphacidae and ((Achilidae + (Lophopidae + (Issidae + (Flatidae + Ricaniidae)))) + Fulgoridae). Furthermore, the monophyly of Fulgoridae was robustly supported, and Aphaeninae was divided into Aphaenini and Pyropsini, which includes Neoalcathous, Pyrops, Datua Schmidt, 1911, and Saiva Distant, 1906. The genus Limois is recovered in the Aphaeninae, and the Limoisini needs further confirmation; Dichoptera sp. was the earliest branch in the Fulgoridae.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ana P. G. S. Wengrat ◽  
Aloisio Coelho Junior ◽  
Jose R. P. Parra ◽  
Tamara A. Takahashi ◽  
Luis A. Foerster ◽  
...  

AbstractThe egg parasitoid Telenomus remus (Hymenoptera: Scelionidae) has been investigated for classical and applied biological control of noctuid pests, especially Spodoptera (Lepidoptera: Noctuidae) species. Although T. remus was introduced into Brazil over three decades ago for classical biological control of S. frugiperda, this wasp has not been recorded as established in corn or soybean crops. We used an integrative approach to identify T. remus, combining a taxonomic key based on the male genitalia with DNA barcoding, using a cytochrome c oxidase subunit I mitochondrial gene fragment. This is the first report of natural parasitism of T. remus on S. frugiperda and S. cosmioides eggs at two locations in Brazil. We also confirmed that the T. remus lineage in Brazil derives from a strain in Venezuela (originally from Papua New Guinea and introduced into the Americas, Africa, and Asia). The occurrence of T. remus parasitizing S. frugiperda and S. cosmioides eggs in field conditions, not associated with inundative releases, suggests that the species has managed to establish itself in the field in Brazil. This opens possibilities for future biological control programs, since T. remus shows good potential for mass rearing and egg parasitism of important agricultural pests such as Spodoptera species.


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