Description of Ganymedes yurii sp. n. (Ganymedidae), a New Gregarine Species from the Antarctic Amphipod Gondogeneia sp. (Crustacea) (original) (raw)

Epimeria schiaparelli sp. nov., an amphipod crustacean (family Epimeriidae) from the Ross Sea, Antarctica, with molecular characterisation of the species complex

Zootaxa, 2007

Epimeria schiaparelli sp. nov. from the Ross Sea, Antarctica, is described in detail. The new species occurs on the shelf in 130–350 m depth. Epimeria schiaparelli can be distinguished from the most similar species, E. similis Chevreux, 1912 and E. macrodonta Walker, 1906 by a relatively short rostrum and a short second pereonite amongst other characters. Two distinct colour patterns are reported. Partial gene sequences of the mitochondrial cytochrome oxidase subunit I (COI) from 11 specimens of E. schiaparelli confirm that this species is new to science and closely related to E. similis, E. macrodonta and E. reoproi. The recent and historical separation of this Antarctic species is discussed. The syntypes of E. macrodonta consist of two species, so a lectotype is here designated.

Epimeria cleo sp. nov., a new crested amphipod from the Ross Sea, Antarctica, with notes on its phylogenetic affinities (Crustacea, Amphipoda, Eusiroidea, Epimeriidae)

Zootaxa, 2018

A new crested amphipod, Epimeria cleo sp. nov., is described after specimens collected in the western Ross Sea, Southern Ocean, at 151–409 m depth. This increases the number of Epimeria species known from the Ross Sea to eleven. This new species belongs to the subgenus Drakepimeria d'Udekem d'Acoz & Verheye, 2017. E. cleo sp. nov. has very robust walking pereiopods, no mid-dorsal tooth or bump on pereonites 1–2, no lateral tooth or angle on the lateral carina of coxa 4 and no pair of small teeth pointing upwards on urosomite 2. It is morphologically very similar to Epimeria leukhoplites d'Udekem d'Acoz & Verheye, 2017, E. reoproi Lörz & Coleman, 2001 and E. vaderi Coleman, 1998, the latter three species being known only from the Antarctic Peninsula and South Shetland Islands. Epimeria cleo sp. nov. can be distinguished from them by the following combination of characters: flexed rostrum, narrow coxa 3, long ventral tooth on coxa 4 and non-duplicate lateral tooth on p...

Morphology and phylogenetic position of two novel marine gregarines (Apicomplexa, Eugregarinorida) from the intestines of North-eastern Pacific ascidians

Zoologica Scripta, 2008

Morphology and phylogenetic position of two novel marine gregarines (Apicomplexa, Eugregarinorida) from the intestines of Northeastern Pacific ascidians. -Zoologica Scripta , 37, 637-645. Eugregarine apicomplexans parasitize marine, freshwater and terrestrial invertebrates, and have lifecycles involving trophozoites (feeding stages) with complex morphologies and behaviour. The genus Lankesteria refers to marine aseptate eugregarines that parasitize ascidians. We described the surface ultrastructure of two new gregarine species, L. chelyosomae sp. n. and L. cystodytae sp. n. that inhabit the intestines of Chelyosoma columbianum and Cystodytes lobatus , respectively, collected from the North-eastern Pacific Ocean. Apart from inhabiting different hosts and major differences in the cell size of L. chelyosomae sp. n. (mean length 182 μ m) and L. cystodytae sp. n. (mean length 70 μ m), the morphology of both gregarine species was quite similar. The trophozoites ranged from elliptoid to obdeltoid in shape and were brownish in colour. The nucleus was situated at the anterior end of the cell just behind a pointed mucron. A dense array of epicytic knobs was present over the entire surface of trophozoites in both species, and longitudinal epicytical folds were only weakly developed. We also sequenced the small subunit rDNA from the gregarines collected from both hosts, which supported the establishment of two new Lankesteria species. Phylogenetic analyses of the new DNA sequences and those derived from other alveolates, demonstrated that both new species clustered in a strongly supported clade consisting of other Lankesteria species, Lecudina species, and some environmental sequences. These morphological and molecular phylogenetic data suggested that improved knowledge of gregarine diversity could lead to the recognition of more than one distinct clade (genus) of gregarines within ascidian hosts.

Contribution to the taxonomic knowledge of Ampharetidae (Annelida) from Antarctica with the description of Amage giacomobovei sp. nov

European Journal of Taxonomy

Thanks to newly collected material from the Terra Nova Bay area (Ross Sea, Antarctica), we discuss the taxonomy of the ampharetid genera Amage Malmgren, 1866 and Amythas Benham, 1921. A new species of Amage, A. giacomobovei sp. nov., is described based on morpho-anatomical data. This is the second new species described from an area which appears to be rich in ampharetids, a coastal embayment at ~500 m depth near the Italian “Mario Zucchelli” research station. The new species is characterized by having 16 abdominal uncinigers and four pairs of branchiae that readily distinguish it from its congeners. Tubes of A. giacomobovei sp. nov. are also characteristic in showing a large amount of embedded sponge spicules, suggesting a possible close association to spicule mats. Based on the amended diagnoses of the two genera, Amage septemdecima Schüller & Jirkov, 2013 is transferred to the genus Amythas. Finally, to simplify the task of ampharetid genera recognition for untrained people, we pr...

Identification of a Divergent Environmental DNA Sequence Clade Using the Phylogeny of Gregarine Parasites (Apicomplexa) from Crustacean Hosts

PLoS ONE, 2011

Background: Environmental SSU rDNA surveys have significantly improved our understanding of microeukaryotic diversity. Many of the sequences acquired using this approach are closely related to lineages previously characterized at both morphological and molecular levels, making interpretation of these data relatively straightforward. Some sequences, by contrast, appear to be phylogenetic orphans and are sometimes inferred to represent ''novel lineages'' of unknown cellular identity. Consequently, interpretation of environmental DNA surveys of cellular diversity rely on an adequately comprehensive database of DNA sequences derived from identified species. Several major taxa of microeukaryotes, however, are still very poorly represented in these databases, and this is especially true for diverse groups of single-celled parasites, such as gregarine apicomplexans.

Molecular relationships of gammaridean amphipods from Arctic sea ice

Polar Biology, 2011

The information on the biology and ecology of the Arctic sea ice-associated amphipods (Apherusa glacialis, Gammarus wilkitzkii, Onisimus glacialis, and O. nanseni) has increased, but their molecular taxonomic information still remains undisclosed. In the present study, we investigated long-range DNA sequences spanning 18S to 28S rDNA of these four sea ice-associated amphipods and analyzed their genetic relationships with other amphipod taxa. Variations of rDNA within the individuals of the same species were not detected. Phylogenetic analyses showed that each ice amphipod was separated, forming clusters with other conspecifics. Pairwise comparisons led to similar phylogenetic results, showing that the molecular taxonomy of the ice amphipods was in accordance with morphological systematics. In addition, these findings suggest that all four amphipods have little genetic variation compared with their morphologically defined conspecifics from temperate regions. Based on DNA taxonomy, G. wilkitzkii was supported as a species in good standing, refuting a recent synonymization with Gammarus duebeni. Considerably low genetic divergences of O. glacialis and O. nanseni in 18S, ITS, and 28S rDNA suggest the presence of population distinctions within species.

Do circum-Antarctic species exist in peracarid Amphipoda? A case study in the genus Epimeria Costa, 1851 (Crustacea, Peracarida, Epimeriidae)

Advances in the taxonomy …, 2009

Citation: Lörz AN, Maas EW, Linse K, Coleman CO (2009) Do circum-Antarctic species exist in peracarid Amphipoda? A case study in the genus Epimeria Costa, 1851 (Crustacea, Peracarida, Epimeriidae). In: Bruce N (Ed) Advances in the taxonomy and biogeography of Crustacea in the Southern Hemisphere. ZooKeys 18: 91-128.

Integrative taxonomy of giant crested Eusirus in the Southern Ocean, including the description of a new species (Crustacea: Amphipoda: Eusiridae)

Zoological Journal of the Linnean Society, 2020

Among Antarctic amphipods of the genus Eusirus, a highly distinctive clade of giant species is characterized by a dorsal, blade-shaped tooth on pereionites 5–7 and pleonites 1–3. This lineage, herein named ‘crested Eusirus’, includes two potential species complexes, the Eusirus perdentatus and Eusirus giganteus complexes, in addition to the more distinctive Eusirus propeperdentatus. Molecular phylogenies and statistical parsimony networks (COI, CytB and ITS2) of crested Eusirus are herein reconstructed. This study aims to formally revise species diversity within crested Eusirus by applying several species delimitation methods (Bayesian implementation of the Poisson tree processes model, general mixed Yule coalescent, multi-rate Poisson tree processes and automatic barcode gap discovery) on the resulting phylogenies. In addition, results from the DNA-based methods are benchmarked against a detailed morphological analysis of all available specimens of the E. perdentatus complex. Our r...