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An ongoing taxonomic inventory of mycophagous gall midges (Cecidomyiidae) in Sweden has revealed several previously unnamed species of asynaptine Porricondylinae, which are described here on the basis of male adults mostly from Malaise trap catches. The new species are classified and named as follows: Asynapta inflatoides sp. nov., A. rickebasta sp. nov., A. taigensis sp. nov., Camptomyia capitata sp. nov., C. hedmarki sp. nov., C. oldhammeri sp. nov., C. rhynchostylata sp. nov., and Stackelbergiella sikorai sp. nov. Specimens studied here prove the presence of both Asynapta inflatoides and A. taigensis in Finland, and of Stackelbergiella sikorai in Estonia. Other species new to the Finnish fauna are Asynapta thuraui Rübsaamen and Camptomyia ulmicola Mamaev, whereas Asynapta inflata Spungis has to be deleted from the Finnish checklist. Males of two species recorded in Sweden for the first time, and three species whose Swedish distribution is reconfirmed here, are redescribed: Asynapta baltica Spungis; A. inflata; Camptomyia fulva Mamaev; C. piptopori Panelius; and C. ulmicola. New junior synonyms recognized here are Niladmirara Fedotova syn. nov. (of Camptomyia Kieffer) and Asynapta panzari Jaschhof & Jaschhof syn. nov. (of A. breviata Spungis). The genitalic morphology of male Asynaptini is reinterpreted to include two pairs of parameres in the ancestral ground pattern. The extraordinary diversity of male genitalic structures found in asynaptine genera is highlighted, along with considerations of how this source of information can be exploited for the benefit of classification. Small-area remnants of ancient, naturally grown forest are shown to support populations of previously unnamed species of Asynaptini.

We report the light-microscopic morphology and ultrastructure of a novel free-living, heterotrophic protist, Creneis carolina gen. et sp. nov. isolated from marine anoxic sediments. C. carolina is a heterotrophic, obligately anaerobic amoeboid flagellate, and superficially resembles Mastigamoeba (Amoebozoa: Archamoebae) or Breviata (Breviatea) by possessing a single anterior flagellum closely associated with the nucleus, and because it appears to be an anaerobe. However, its life cycle contains multiflagellate cells with an unusual morphology. The structure of the mastigont of C. carolina is unique and not readily comparable with any eukaryotic group. Unexpectedly, phylogenetic analyses of SSU rDNA and of a concatenate of α- and β-tubulin genes with SSU rDNA convincingly showed that C. carolina is a member of Heterolobosea and belongs to the taxon Tetramitia.

Breviata anathema is an anaerobic amoeboid flagellate that does not branch within any established ‘supergroup’. Molecular phylogenies suggest affinities to Amoebozoa, Opisthokonta, or apusomonads. Here we describe its flagellar apparatus ultrastructure. Breviata has two basal bodies. The flagellated anterior basal body (AB) is associated with a fan of ∼18 microtubules and a short singlet microtubular root. Three microtubular roots associate with the posterior basal body. One, the right root (RR), is initially a triplet that splits into two parts. The other two are singlets: the left root (LR), and the middle root (MR), which arises on the posterior side of the basal body. The MR, LR and smaller part of RR support the left ventral side of the cell, while the larger part of RR runs down the right. Outer dynein arms were not observed on the flagellar axoneme. The mitochondrion-like organelle sometimes contains some tubular cristae. The posterior flagellar apparatus resembles that of several eukaryotic lineages, particularly apusomonads, ancyromonads, excavates, and myxogastrid amoebozoans. This comparison suggests that the complex flagellar apparatus of myxogastrids is actually plesiomorphic within Amoebozoa. The widely distributed splitting right root and posterior singlet (MR in Breviata) may be plesiomorphies in many eukaryotic lineages, and thus could be features of the last eukaryotic common ancestor.

The new genus Hirsutapona is described and compared to the similar genus Hecalapona. The new genus contains H. aspira (DeLong and Freytag), new combination, type species and H. titula (DeLong and Freytag), new combination, previously included in Hecalapona (Carapona), and the following 19 new species, H. breviata, H. godoyae, H. hansoni, H. inflata, H. labella, H. lata, H. limba, H. mera and H. meta from Costa Rica; H. angula, H. delicata, H. granda, and H. prona from French Guiana; H. minuta from French Guiana and Suriname: H. myersi and H. munda from Ecuador; H. dietzi and H. metana from Venezuela; and H. mediata from Brazil.

While a large number of aerobic free-living protists have been described within the last decade, the number of new anaerobic or microaerophilic microbial eukaryotic taxa has lagged behind. Here we describe a microaerophilic genus and species of amoeboflagellate isolated from a near-shore marine site off the coast at Plymouth, Massachusetts: Subulatomonas tetraspora nov. gen. nov. sp. This taxon is closely related to Breviata anathema based on both microscopical features and phylogenetic analyses of sequences of three genes: SSU-rDNA, actin, and alpha-tubulin. However, Subulatomonas tetraspora nov. gen. nov. sp. and B. anathema are morphologically distinctive, differ by 14.9% at their SSU-rDNA locus, and were isolated from marine and ‘slightly brackish’ environments, respectively. Phylogenetic analyses of these two taxa plus closely related sequences from environmental surveys provide support for a novel clade of eukaryotes that is distinct from the major clades including the Opisthokonta, Excavata, Amoebozoa and ‘SAR’ ( S tramenopile, A lveolate, R hizaria).

Mantamonas is a novel genus of marine gliding zooflagellates probably related to apusomonad and planomonad Apusozoa. Using phase and differential interference contrast microscopy we describe the type species Mantamonas plastica sp. n. from coastal sediment in Cumbria, England. Cells are ∼5 μm long, ∼5 μm wide, asymmetric, flattened, biciliate, and somewhat plastic. The posterior cilium, on which they glide smoothly over the substratum, is long and highly acronematic. The much thinner, shorter, and almost immobile anterior cilium points forward to the cell's left. These morphological and behavioural traits suggest that Mantamonas is a member of the protozoan phylum Apusozoa. Analyses of 18S and 28S rRNA gene sequences of Mantamonas plastica and a second genetically very different marine species from coastal sediment in Tanzania show Mantamonas as a robustly monophyletic clade, that is very divergent from all other eukaryotes. 18S rRNA trees mostly place Mantamonas within unikonts (opisthokonts, Apusozoa, and Amoebozoa) but its precise position varies with phylogenetic algorithm and/or taxon and nucleotide position sampling; it may group equally weakly as sister to Planomonadida, Apusomonadida or Breviata. On 28S rRNA and joint 18/28S rRNA phylogenies (including 11 other newly obtained apusozoan/amoebozoan 28S rRNA sequences) it consistently strongly groups with Apusomonadida (Apusozoa).

Endosomal sorting complexes required for transport (ESCRTs) are heteromeric protein complexes required for multivesicular body (MVB) morphogenesis. ESCRTs I, II, III and III-associated are ubiquitous in eukaryotes and presumably ancient in origin. ESCRT 0 recruits cargo to the MVB and appears to be opisthokont-specific, bringing into question aspects of the current model of ESCRT mechanism. One caveat to the restricted distribution of ESCRT 0 was the previous limited availability of amoebozoan genomes, the supergroup closest to opisthokonts. Here, we significantly expand the sampling of ESCRTs in Amoebozoa. Our electron micrographic and bioinformatics evidence confirm the presence of MVBs in the amoeboflagellate Breviata anathema. Searches of genomic databases of amoebozoans confirm the ubiquitous nature of ESCRTs I–III-associated and the restriction of ESCRT 0 to opisthokonts. Recently, an alternate ESCRT 0 complex, centering on Tom1 proteins, has been proposed. We determine the distribution of Tom1 family proteins across eukaryotes and show that the Tom1, Tom1L1 and Tom1L2 proteins are a vertebrate-specific expansion of the single Tom1 family ancestor, which has indeed been identified in at least one member of each of the major eukaryotic supergroups. This implies a more widely conserved and ancient role for the Tom1 family in endocytosis than previously suspected.

The leafhopper genus Drakensbergena is revised. Two species are redescribed: the type-species, D. fuscovittata Linnavuori and D. ochracea Linnavuori. The following 16 species are described as new: D. armstrongi, D. austrina, D. bisulca, D. breviata, D. cuneifer, D. deorsuspina, D. festucacola, D. gigascutica, D. labeona, D. lobulata, D. longinqua, D. phaeogramma, D. prolixa, D. retrospina, D. simulata and D. spinula. Keys are provided for the identification of all the species.

An understanding of large-scale eukaryotic evolution is beginning to crystallise, as molecular and morphological data demonstrate that eukaryotes fall into six major groups. However, there are several taxa of which the affinities are yet to be resolved, and for which there are only either molecular or morphological data. One of these is the amoeboid flagellate Mastigamoeba invertens. This organism was originally misidentified and studied as a pelobiont using molecular data. We present its first light microscopical and ultrastructural characterisation. We demonstrate that it does not show affinities to the amoebozoan pelobionts, because unlike the pelobionts, it has a double basal body and two flagellar roots, a classical Golgi stack, and a large branching double membrane-bound organelle. Phylogenetic analyses of small subunit ribosomal RNA suggest an affinity with the apusomonads, when a covariotide correction for rate heterogeneity is used. We suggest that previous molecular results have been subject to artefacts from an insufficient correction for rate heterogeneity. We propose a new name for the taxon, Breviata anathema; and the unranked, apomorphy-based name "Breviates" for Breviata and its close relatives.

The paper continues describing new genera and species of arrowworms from the southwestern Bering Sea and northwestern Pacific (see Kasatkina [2–4]). Diagnoses are presented for two new genera, Protokrohnittella and Protoeukrohnia and six new species of the genus Pseudoeukrohnia (Ps. beringi sp. n., Ps. breviata sp. n., Ps. nesmeyanovi sp. n., Ps. aculeata sp. n., Ps. speciosa sp. n., and Ps. lata sp. n.). Detailed descriptions are presented, provided with drawings and differential diagnoses. The phenomenon of global replacement in the deep-sea and mesopelagial faunas of arrowworms (Chaetognatha) in the western Bering Sea has been confirmed.

SummaryA recent phylogenomic investigation shows that the enigmatic flagellate Breviata is a distinct anaerobic lineage within the eukaryote super-group Amoebozoa and challenges the unikont–bikont rooting of the tree of eukaryotes.

Most eukaryotic lineages belong to one of a few major groups. However, several protistan lineages have not yet been robustly placed in any of these groups. Both the breviates and apusomonads are two such lineages that appear to be related to the Amoebozoa and Opisthokonta (i.e. the ‘unikonts’ or Amorphea); however, their precise phylogenetic positions remain unclear. Here, we describe a novel microaerophilic breviate, Pygsuia biforma gen. nov. sp. nov . , isolated from a hypoxic estuarine sediment. Ultrastructurally, this species resembles the breviate genera Breviata and Subulatomonas but has two cell morphologies, adherent and swimming. Phylogenetic analyses of the small sub-unit rRNA gene show that Pygsuia is the sister to the other breviates. We constructed a 159-protein supermatrix, including orthologues identified in RNA-seq data from Pygsuia . Phylogenomic analyses of this dataset show that breviates, apusomonads and Opisthokonta form a strongly supported major eukaryotic grouping we name the Obazoa. Although some phylogenetic methods disagree, the balance of evidence suggests that the breviate lineage forms the deepest branch within Obazoa. We also found transcripts encoding a nearly complete integrin adhesome from Pygsuia , indicating that this protein complex involved in metazoan multicellularity may have evolved earlier in eukaryote evolution than previously thought.

The importance of bacteria in the anaerobic bioremediation of groundwater polluted with organic and/or metal contaminants is well recognized and in some instances so well understood that modeling of the in situ metabolic activity of the relevant subsurface microorganisms in response to changes in subsurface geochemistry is feasible. However, a potentially significant factor influencing bacterial growth and activity in the subsurface that has not been adequately addressed is protozoan predation of the microorganisms responsible for bioremediation. In field experiments at a uranium-contaminated aquifer located in Rifle, CO, USA, acetate amendments initially promoted the growth of metal-reducing Geobacter species, followed by the growth of sulfate reducers, as observed previously. Analysis of 18S rRNA gene sequences revealed a broad diversity of sequences closely related to known bacteriovorous protozoa in the groundwater before the addition of acetate. The bloom of Geobacter species was accompanied by a specific enrichment of sequences most closely related to the ameboid flagellate, Breviata anathema, which at their peak accounted for over 80% of the sequences recovered. The abundance of Geobacter species declined following the rapid emergence of B. anathema. The subsequent growth of sulfate-reducing Peptococcaceae was accompanied by another specific enrichment of protozoa, but with sequences most similar to diplomonadid flagellates from the family Hexamitidae, which accounted for up to 100% of the sequences recovered during this phase of the bioremediation. These results suggest a prey–predator response with specific protozoa responding to increased availability of preferred prey bacteria. Thus, quantifying the influence of protozoan predation on the growth, activity and composition of the subsurface bacterial community is essential for predictive modeling of in situ uranium bioremediation strategies.

Integration of ultrastructural and molecular sequence data has revealed six supergroups of eukaryote organisms (excavates, Rhizaria, chromalveolates, Plantae, Amoebozoa and opisthokonts), and the root of the eukaryote evolutionary tree is suggested to lie between unikonts (Amoebozoa, opisthokonts) and bikonts (the other supergroups). However, some smaller lineages remain of uncertain affinity. One of these unassigned taxa is the anaerobic, free-living, amoeboid flagellate Breviata anathema , which is of key significance as it is unclear whether it is a unikont (i.e. possibly the deepest branching amoebozoan) or a bikont. To establish its evolutionary position, we sequenced thousands of Breviata genes and calculated trees using 78 protein sequences. Our trees and specific substitutions in the 18S RNA sequence indicate that Breviata is related to other Amoebozoa, thereby significantly increasing the cellular diversity of this phylum and establishing Breviata as a deep-branching unikont. We discuss the implications of these results for the ancestral state of Amoebozoa and eukaryotes generally, demonstrating that phylogenomics of phylogenetically ‘nomadic’ species can elucidate key questions in eukaryote evolution. Furthermore, mitochondrial genes among the Breviata ESTs demonstrate that Breviata probably contains a modified anaerobic mitochondrion. With these findings, remnants of mitochondria have been detected in all putatively deep-branching amitochondriate organisms.

The diversity of mitochondria-like organelles is not restricted to the best-studied examples presented in the previous chapters. The recognised diversity of anaerobic and microaerophilic organisms is broader and they are distributed all across the eukaryotic tree. Many of them – pelobionts, most or all metamonads, anaerobic heteroloboseans, Postgaardi, Andalucia incarcerata and Breviata – harbour double membrane-bounded organelles that do not resemble classical mitochondria, in the sense that they do not have cristae, but are probably homologous to them. For various reasons, these organelles, and the organisms in which they are found, have been studied very little. For example, most of these taxa are not significant from a medical or economic perspective, some were recognised only recently and many are difficult to handle in the laboratory. Therefore, the relationship of these organelles to mitochondria and their functional properties are deduced, so far, only from indirect evidence including the presence of a double-membrane envelope, their association with hydrogen consuming methanogens and the discovery of mitochondrion- or hydrogenosome-specific genes in the organism's genome. Although studies on the metabolic properties of these organelles will struggle with technical obstacles, they promise interesting insights into the versatility of mitochondrial structure and function, and the evolution of anaerobic/microaerophilic life histories.

33 species of Chrisopini are described and illustrated, of wich 30 are recorded from the Amazon Basin. Ten new species are described in Chrisopodes(duckei, spínella, nebulosa, lineafrons, polygonica, indetata, conisetosa, breviata, mediocris, and tetifera(, and nine in Ceraesochrysa(squalidens, acutipuppis, rafaeli, reddyi, nigripes, teneuícornis, ariasi, falceifera, and michaelmuris). Neosuarus (type species collaris (Schneider), a new subgenus of Chrysopodes, also contains divisa (Walker), escomeli (Navás) porterina (Navás), and flavescens (Blanchard). Orlandsia Navás and Ancylochrysa Navás are synonymized with Chrysopodes limbata (Navás), Chrysoperla asoralis (Banks) and Suarius nesotala (Banks). A neotype is designate for Ceraeochrysa cubana (Hagen). Ceraeochrysa caligata(Banks) and scapularis (Navás) are valid species. C. gloriae Alayo is synonymized with Ceraeochrysa everes (Banks). As 30 espécies de Chrysopini conhecidas da Bacia Amazônica são descritas, ilustradas, e chaves dadas para suas identificações. Dezenove espécies novas e um subgênero novo de Chrysopodes, Neosuarius, são descritas. Os nomes genéricos Orlandsia Navás e Ancylochrysa Navás são sinonimizados com Chrysopodes.