Stramenopiles represent a significant proportion of aquatic and terrestrial biota. Most biologists can name a few, but these are limited to the phototrophic (e.g. diatoms and kelp) or parasitic species (e.g. oomycetes, Blastocystis), with free-living heterotrophs largely overlooked. Though our attention is slowly turning towards heterotrophs, we have only a limited understanding of their biology due to a lack of cultured models. Recent metagenomic and single-cell investigations have revealed the species richness and ecological importance of stramenopiles-especially heterotrophs. However, our lack of knowledge of the cell biology and behaviour of these organisms leads to our inability to match species to their particular ecological functions. Because photosynthetic stramenopiles are studied independently of their heterotrophic relatives, they are often treated separately in the literature. Here, we present stramenopiles as a unified group with shared synapomorphies and evolutionary history. We introduce the main lineages, describe their important biological and ecological traits, and provide a concise update on the origin of the ochrophyte plastid. We highlight the crucial role of heterotrophs and mixotrophs in our understanding of stramenopiles with the goal of inspiring future investigations in taxonomy and life history. To understand each of the many diversifications within stramenopiles-towards autotrophy, osmotrophy, or parasitism-we must understand the ancestral heterotrophic flagellate from which they each evolved. We hope the following will serve as a primer for new stramenopile researchers or as an integrative refresher to those already in the field.

• Keywords
• chromalveolate hypothesis, heterotrophic flagellates, microbial ecology and evolution, plastid evolution, protistology, rhodoplex hypothesis, stramenopiles,
• MeSH
• Biological Evolution MeSH
• Phylogeny MeSH
• Stramenopiles * classification   genetics   MeSH
• Heterotrophic Processes * MeSH
• Plastids genetics   MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Paradiplozoon opsariichthydis (Jiang, Wu et Wang, 1984) Jiang, Wu et Wang, 1989 (Platyhelminthes, Monogenea, Diplozoidae) is blood-feeding parasite from the gills of Asian cyprinid fish Opsariichthys bidens Günther, 1873. In this study, we present a morphological redescription of P. opsariichthydis neotype main morphological features e.g. size of body and clamps due to the fact that the type material is missing. We decided to supplement morphological descriptions by the relevant molecular data (internal transcribed spacer - ITS2) related to P. opsariichthydis adult worm isolates and other representatives of genus Paradiplozoon to cross verify our findings. In addition to that, this study also brings an attention to the host identification. Thus, parasite data were complemented by the determinant cytochrome oxidase b (cytb) sequences of its hosts. All novel sequences are deposited in GenBank. This combination of the morphological and molecular data related to both the parasite and its host seems to be the optimal approach to the general process of (re)description of highly host-specific parasitic organisms, which can then lead to a meaningful phylogenetic analysis.

• Keywords
• Blood-feeding ectoparasite, Chinese fish parasite, Morphological and molecular identification of species, Neotype, Phylogenetic analysis,
• MeSH
• Cyprinidae * MeSH
• Cytochromes b analysis   MeSH
• DNA, Helminth analysis   MeSH
• Phylogeny * MeSH
• Trematode Infections parasitology   MeSH
• Host-Parasite Interactions * MeSH
• DNA, Ribosomal Spacer analysis   MeSH
• Fish Diseases parasitology   MeSH
• Fish Proteins analysis   MeSH
• Trematoda anatomy & histology   classification   genetics   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• Cytochromes b MeSH
• DNA, Helminth MeSH
• DNA, Ribosomal Spacer MeSH
• Fish Proteins MeSH

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

• Publication type
• Published Erratum MeSH

Cryptic genetic diversity and erroneous morphological species determination represent frequent problems in biodiversity research. Here, examination of 138 specimens of Synodontis (Mochokidae, Siluriformes) from the Nile River and Lake Turkana revealed the presence of both S. schall-like and S. frontosus-like morphotypes, with a phenotypic gradient between them. We concluded phylogenetic and population genetic analyses based on two mitochondrial and one nuclear marker including 131 coxI (565 bp), 96 cytb (973 bp) and 19 RAG2 (896 bp) sequences from the Nile-Turkana population, plus additional GenBank data of Synodontis spp. Whilst nuclear data were inconclusive, mitochondrial sequences suggested that both morphotypes and intermediate forms are conspecific. The results imply probable synonymy of S. frontosus with S. schall. Conversely, a strong biogeographical signal was revealed among widely distributed and supposedly conspecific S. schall-like catfish of the Nilo-Sudanian ichthyological province. Synodontis schall sensu stricto (=Eastern clade), as defined by type locality in the Nile, is apparently restricted to the eastern part of the Nilo-Sudanian ichthyological province (e.g. Nile, Turkana, Chad). Synodontis schall Western clade (Senegambia, Niger, Chad) most probably represents a cryptic taxon, unrecognized thus far due to the absence of distinctive morphological differences.

• MeSH
• Bayes Theorem MeSH
• Biodiversity * MeSH
• Cytochromes b classification   genetics   MeSH
• Phylogeny MeSH
• Haplotypes MeSH
• Genetics, Population MeSH
• Electron Transport Complex IV classification   genetics   MeSH
• Catfishes classification   genetics   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Cytochromes b MeSH
• Electron Transport Complex IV MeSH

In this paper, we describe a novel bacteriophagous biflagellate, Cafileria marina with two smooth flagellae, isolated from material collected from a rock surface in the Kvernesfjorden (Norway). This flagellate was characterized by scanning and transmission electron microscopy, fluorescence, and light microscopy. The sequence of the small subunit ribosomal RNA gene (18S) was used as a molecular marker for determining the phylogenetic position of this organism. Apart from the nuclear ribosomal gene, the whole mitochondrial genome was sequenced, assembled, and annotated. Morphological observations show that the newly described flagellate shares key ultrastructural characters with representatives of the family Bicosoecida (Heterokonta). Intriguingly, mitochondria of C. marina frequently associate with its nucleus through an electron-dense disc at the boundary of the two compartments. The function of this association remains unclear. Phylogenetic analyses corroborate the morphological data and place C. marina with other sequence data of representatives from the family Bicosoecida. We describe C. marina as a new species from a new genus in this family.

• Keywords
• bicosoecida, flagellar apparatus, heterokonta, heterotrophic nano-flagellate, new genus, phylogeny,
• Publication type
• Journal Article MeSH

Paradiplozoon hemiculteri (Ling, 1973), a member of the Diplozoidae, parasitizes the gills of Asian fish. Not only is the type material unavailable for this species, the original description was poor and somewhat conflicting, and adequate molecular data were not available. What is more, the available morphological and molecular data are inconsistent and fluctuate significantly. Here, we present a redescription of P. hemiculteri based on morphological and molecular data from new isolates collected from the type host, the sharpbelly Hemiculter leucisculus (Basilewsky, 1855), captured at the neotype locality (Shaoguan, Guangdong Province, southern China); a neotype for P. hemiculteri was designated from this collection. The length and width of the body, buccal suckers, pharynx, attachment clamps, sickle and the central hook handle were all measured and the shape of the anterior and posterior part of the median plate and anterior and posterior joining sclerites accurately documented. Phylogenetic analyses based on the sequences of the second rDNA internal transcribed spacer (ITS2) indicated that all new samples clustered together and differed clearly from sequences attributed to P. hemiculteri, which are deposited in GenBank. Our results confirm that P. hemiculteri is the only diplozoid that has demonstrably been found on the gills of H. leucisculus to date.

Paradiplozoon hemiculteri (Ling, 1973), membre des Diplozoidae, parasite les branchies des poissons asiatiques. Non seulement le matériel-type n’est pas disponible pour cette espèce, mais la description originale était médiocre et quelque peu contradictoire, et des données moléculaires adéquates n’étaient pas disponibles. Qui plus est, les données morphologiques et moléculaires disponibles sont incohérentes et fluctuent de manière significative. Ici, nous présentons une nouvelle description de P. hemiculteri basée sur des données morphologiques et moléculaires provenant de nouveaux isolats recueillis chez l’hôte-type, Hemiculter leucisculus (Basilewsky, 1855), capturé à la localité du néotype (Shaoguan, province du Guangdong, sud de la Chine); un néotype pour P. hemiculteri a été désigné à partir de cette collection. La longueur et la largeur du corps, les ventouses buccales, le pharynx, les pinces, la faucille et la poignée centrale ont été mesurés et la forme de la partie antérieure et postérieure de la plaque médiane et des sclérites antérieurs et postérieurs bien documentée. Des analyses phylogénétiques basées sur les séquences du second espaceur transcrit interne de l’ADNr (ITS2) ont indiqué que tous les nouveaux échantillons étaient regroupés et différaient clairement des séquences attribuées à P. hemiculteri qui sont déposées dans GenBank. Nos résultats confirment que P. hemiculteri est le seul Diplozoidae qui ait été trouvé sur les branchies de H. leucisculus à ce jour.

• MeSH
• Cyprinidae parasitology   MeSH
• DNA, Helminth chemistry   MeSH
• Phylogeny * MeSH
• Trematode Infections epidemiology   parasitology   veterinary   MeSH
• DNA, Ribosomal Spacer chemistry   MeSH
• Fish Diseases epidemiology   parasitology   MeSH
• Trematoda classification   genetics   isolation & purification   MeSH
• Gills parasitology   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• China epidemiology   MeSH
• Names of Substances
• DNA, Helminth MeSH
• DNA, Ribosomal Spacer MeSH

Biogeographical and ecological barriers strongly affect the course of micro-evolutionary processes in free living organisms. Here we assess the impact of a recently emerged barrier on populations of limnic fauna. Genetic diversity and population structure in a host-parasite system (Wenyonia virilis tapeworm, Synodontis schall catfish) are analyzed in the recently divided Turkana and Nile basins. The two basins, were repeatedly connected during the Holocene wet/dry climatic oscillations, following late Pleistocene dessication of the Turkana basin. Mitochondrial DNA sequences for cytochrome oxidase I gene (cox I) and a whole genome scanning method-amplified fragment length polymorphism (AFLP) were employed. A total of 347 cox I sequences (representing 209 haplotypes) and 716 AFLP fragments, as well as 120 cox I sequences (20 haplotypes) and 532 AFLP fragments were obtained from parasites and hosts, respectively. Although results indicate that host and parasite populations share some formative traits (bottlenecks, Nilotic origin), their population histories/patterns differ markedly. Mitochondrial analysis revealed that parasite populations evolve significantly faster and show remarkably higher genetic variability. Analyses of both markers confirmed that the parasites undergo lineage fission, forming new clusters specific for either freshwater or saline parts of Lake Turkana. In congruence with the geological history, these clusters apparently indicate multiple colonisations of Lake Turkana from the Nile. In contrast, the host population pattern indicates fusion of different colonisation waves. Although fish host populations remain connected, saline habitats in Lake Turkana (absent in the Nile), apparently pose a barrier to the gene flow in the parasite, possibly due to its multihost lifecycle, which involves freshwater annelids. Despite partially corroborating mitochondrial results, AFLP data was not sufficiently informative for analyzing populations with recently mixed biogeographic histories.

• MeSH
• Cestoda genetics   MeSH
• Cestode Infections genetics   parasitology   veterinary   MeSH
• Ecosystem MeSH
• Extreme Environments * MeSH
• Phylogeny MeSH
• Haplotypes MeSH
• Host-Parasite Interactions genetics   MeSH
• Lakes MeSH
• DNA, Mitochondrial MeSH
• Evolution, Molecular * MeSH
• Fish Diseases genetics   parasitology   MeSH
• Polymorphism, Genetic MeSH
• Helminth Proteins genetics   MeSH
• Electron Transport Complex IV genetics   MeSH
• Saline Waters MeSH
• Catfishes genetics   parasitology   MeSH
• Models, Theoretical MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Kenya MeSH
• Names of Substances
• DNA, Mitochondrial MeSH
• Helminth Proteins MeSH
• Electron Transport Complex IV MeSH