Systematic revision of Entomobryidae (Collembola) by integrating molecular and new morphological evidence

Entomobryidae, the largest collembolan family, is traditionally classified at suprageneric level using a limited set of morphological structures, such as scales, antennal segmentation. Most tribal and subfamilial delimitations appear, however, disputable in the light of recent works. Integrating molecular and morphological evidence, we propose here a revision of the systematics of the family. In addition to traditional taxonomic characters, tergal specialized chaetae (S‐chaetae) are newly introduced, and their patterns are shown to be diversified at all levels from species to subfamilies. S‐chaetotaxic pattern on phylogenetic tree shows that evolution of S‐chaetae is not parallel between the different terga and that their patterns coincide well with the known molecular phylogeny, providing a powerful tool for the systematics of Entomobryidae. Orchesellinae sensu Soto‐Adames et al. (Annals of the Entomological Society of America, 101, 2008, 501); is divided into three subfamilies: Orchesellinae s. s., Bessoniellinae and Heteromurinae, the latter two upgraded from the original tribal level. Entomobryinae sensu Szeptycki (Morpho‐Systematic Studies on Collembola. IV. Chaetotaxy of the Entomobryidae and its Phylogenetical Significance, 1979), is no longer divided into scaled and unscaled tribes, and Lepidosira‐group is transferred from Seirinae to Entomobryinae. A key to subfamilies and tribes and a comparison with previous classifications of the Entomobryidae are provided. This study greatly improves the understanding of primary and secondary characters and erects the fundamental framework for the taxonomy of Entomobryidae.     

Salsuginus neotropicalis n. sp. (Monogenea: Ancyrocephalinae) from the pike killifish Belonesox belizanus (Atheriniformes: Poeciliidae) from southeastern Mexico

Salsuginus neotropicalis n. sp. is described from the gills of Belonesox belizanus (Kner), the pike killifish (Poeciliidae), from the southeastern Mexico. S. neotropicalis is distinguished from all other congeners by the morphology of the haptoral sclerites, especially by the presence of a ventral bar with notably enlarged ends, and by possessing overlapping gonads. The diagnosis of Salsuginus is amended based on the position of gonads in this species. This is the first known Salsuginus species occurring in a freshwater fish from the Neotropical Region.     

Diversity in the genus Rhabdias (Nematoda,Rhabdiasidae): Evidence for cryptic speciation

Lungworms from the genus Rhabdias are common parasites of amphibians and reptiles distributed worldwide. To assess the diversity of Rhabdias spp., we performed molecular analyses of 35 specimens sampled in different regions of Brazil. Molecular analyses were based on the internal transcribed spacer (ITS), large subunit (28S) ribosomal and the cytochrome oxidase I (COI) mitochondrial genes. DNA sequence divergence was compared among ribosomal and mitochondrial genes, analyses using the general mixed Yule‐coalescent (GMYC) method based on the COI gene were used to identify possible cryptic diversity, and phylogenetic analyses using concatenated ITS and 28S ribosomal genes were used to test the monophyly of Rhabdiasidae. We revealed five morphospecies: R. cf. stenocephala, R. breviensis, R. pseudosphaerocephala and two new species, Rhabdias sp.4 and Rhabdias sp.5. DNA sequence levels of divergence among genes ITS, 28S and COI were compared, and the efficiency of the molecular markers to identify species (ITS and COI) and lineages (COI) was tested. GMYC was assigned to 17 well‐supported clades (i.e., 17 species), and cryptic diversity was detected in the Neotropical region as evidenced by the multiple lineages in R. breviensis and R. pseudosphaerocephala. In addition, our results suggest evidence for host–parasite cophylogeny in the R. pseudosphaerocephala complex and dispersal events among their populations. Phylogenetic analyses supported the monophyly of Rhabdiasidae and improved the resolution of main clades. Rhabdias breviensis is closely related to Rhabdias cf. africanus, Rhabdias cf. stenocephala, R. pseudosphaerocephala, Rhabdias sp.4 and Rhabdias sp.5 grouping together in a main clade with Neotropical‐related species. The large geographical distribution appeared to be a phylogenetic pattern among the species of Rhabdias from the neotropics.     

Morphological and molecular data of new species of Characithecium and Diaphorocleidus (Monogenea: Dactylogyridae) from Neotropical characid fishes

The present study describes three new species of monogenean parasites of characid fishes from the Upper Paraná River basin, Brazil: Characithecium paranapanemense n. sp. on Psalidodon paranae and Psalidodon bockmanni, Diaphorocleidus magnus n. sp. on Astyanax lacustris and Psalidodon fasciatus, and Diaphorocleidus neotropicalis n. sp. on Astyanax lacustris and P. bockmanni. An amendment for Diaphorocleidus is proposed, since additional characters observed in the new species required to extend the generic diagnostic features mainly to include: articulation process connecting the base of the MCO with accessory piece present or absent, and accessory piece with variable shapes (plate-like, pincer-shaped, wrench-shaped, sheath-shaped), divided or not into subunits. Characithecium paranapanemense n. sp. can be distinguished from other congeners by the morphology of its MCO and accessory piece. Diaphorocleidus magnus n. sp. differs from most of its congeners by the morphology of its accessory piece, the presence of articulation process connecting the base of the MCO with accessory piece, and the morphology of the sclerotized structures of the haptor. Diaphorocleidus neotropicalis n. sp. can be easily distinguished from its congeners by the morphology of the accessory piece, the sclerotized structures of the haptor and the morphology of the vagina. Molecular data of the new species (partial 28S rDNA and mitochondrial cytochrome oxidase I) were obtained and the first phylogenetic analysis based on 28S rDNA gene sequences for species of Characithecium and Diaphorocleidus are provided. Although Diaphorocleidus and Characithecium share some morphological similarities, phylogenetic analysis indicates that species of these two genera are not closely related.     

Morphology,morphogenesis and molecular phylogeny of a novel saline soil ciliate,Urosoma quadrinucleatum n. sp. (Ciliophora,Hypotrichia)

The morphology and morphogenesis of a new saline soil hypotrichous ciliate, Urosoma quadrinucleatum n. sp., collected from northwestern China, were studied based on live observations and protargol stained specimens. The new species is characterized as follows: size in vivo 90–130 × 20–30 μm; body outline elongate-elliptical with both ends broadly rounded; four macronuclear nodules; cortical granules present; paroral in front of endoral; usually 16 frontal-ventral-transverse cirri. Urosoma quadrinucleatum n. sp. has almost the same morphogenetic characteristics as its congeners U. gigantea and U. salmastra, and differs from other three congeners whose morphogenesis is known in the formation of the frontal-ventral-transverse cirral anlagen as well as the development of marginal and dorsal kineties anlagen. The sequence differences among U. quadrinucleatum n. sp. and other Urosoma species further support the validity of the present organism as novel species. Further, U. quadrinucleatum n. sp. clusters with U. salmastra in the phylogenetic analyses based on small subunit ribosomal RNA gene (SSU rDNA) sequence data.     

Molecules and morphology reveal a new aberrant harvestman genus of Ortholasmatinae (Opiliones,Dypsnoi, Nemastomatidae) from Mexico

Ortholasmatinae is one of the most striking groups of Opiliones, because its members exhibit a peculiar dorsal ornamentation pattern of cells, formed by fusion of anvil-shaped tubercles. During the systematic revision of several specimens of ortholasmatines, we found specimens with shared morphological characters with two genera Trilasma Goodnight & Goodnight, 1942 and Dendrolasma Banks, 1894. In order to investigate their phylogenetic relationships, we performed model-based phylogenetic analyses using the mitochondrial protein-encoding cytochrome c oxidase subunit 1 (CO1) and the complete nuclear ribosomal small subunit 18S, including members of the five genera of this subfamily. The results support the creation of Cryptolasma Cruz-López, Cruz-Bonilla & Francke, gen. nov., and two new species: Cryptolasma aberrante Cruz-López, Cruz-Bonilla & Francke, sp. nov. (type species) and Cryptolasma citlaltepetl Cruz-López, Cruz-Bonilla & Francke, sp. nov., which are from Xalapa and Orizaba Volcano, Veracruz, respectively. Additionally, our results suggest Ruaxphilos petrukenvitchou Goodnight & Goodnight, 1945 is a nomina dubia. This study represents the first molecular hypothesis of Ortholasmatinae relationships, with Cryptolasma as the sister of the remaining ortholasmatine.www.zoobank.org/urn:lsid:zoobank.org:pub:3730EE48-9802-4B06-9DDF-EC1AFE9A3B61     

Two New Species of Trypanosomatid Parasites Isolated from Heteroptera in Costa Rica

ABSTRACT. Two new trypanosomatid species (Euglenozoa, Kinetoplastea) isolated from the intestinal tract of heteropteran insect hosts were described based on molecular phylogenetic analyses of Spliced Leader (SL) RNA gene repeats, glycosomal glyceraldehyde phosphate dehydrogenase, and small subunit ribosomal RNA genes, as well as by morphology. Leptomonas barvae n. sp., from a mirid host Collaria oleosa, was found to represent one of the closest monoxenous (one host) relatives of the dixenous (two hosts) parasitic genus Leishmania. This finding further supports the origin of these dixenous parasites from monoxenous progenitors in the Neotropics. Blastocrithidia largi n. sp., from a largid host Largus cinctus, is among a few members of this genus available in culture. The species is a close relative of Blastocrithidia triatomae and is a member of a new monophyletic phylogenetic group characterized by formation of straphanger cysts.     

A New Heterotrophic Cryptomonad: Hemiarma marina n. g., n. sp.

We report a new heterotrophic cryptomonad Hemiarma marina n. g., n. sp. that was collected from a seaweed sample from the Republic of Palau. In our molecular phylogenetic analyses using the small subunit ribosomal RNA gene, H. marina formed a clade with two marine environmental sequences, and the clade was placed as a sister lineage of the freshwater cryptomonad environmental clade CRY1. Alternatively, in the concatenated large and small subunit ribosomal RNA gene phylogeny, H. marina was placed as a sister lineage of Goniomonas. Light and electron microscopic observations showed that H. marina shares several ultrastructural features with cryptomonads, such as flattened mitochondrial cristae, a periplast cell covering, and ejectisomes that consist of two coiled ribbon structures. On the other hand, H. marina exhibited unique behaviors, such as attaching to substrates with its posterior flagellum and displaying a jumping motion. H. marina also had unique periplast arrangement and flagellar transitional region. On the basis of both molecular and morphological information, we concluded that H. marina should be treated as new genus and species of cryptomonads.     

Cochlodinium fulvescens sp. nov. (Gymnodiniales, Dinophyceae), a new chain-forming unarmored dinoflagellate from Asian coasts

Cellular morphology and the phylogenetic position of a new unarmored photosynthetic dinoflagellate Cochlodinium fulvescens Iwataki, Kawami et Matsuoka sp. nov. were examined by light microscopy and molecular phylogenetic analyses based on partial large subunit ribosomal DNA (LSU rDNA) and small subunit ribosomal DNA (SSU rDNA) sequences. The cells of C. fulvescens closely resemble C. polykrikoides, one of the most harmful red tide forming dinoflagellates, due to it possessing a cingulum encircling the cell approximately twice, a spherical nucleus positioned in the anterior part of the cell and an eyespot‐like orange pigmented body located in the dorsal side of the epicone, as well as formation of cell‐chains. However, this species is clearly distinguished from C. polykrikoides based on several morphological characteristics, namely, cell size, shape of chloroplasts and the position of narrow sulcus situated in the cell surface. The sulcus of C. fulvescens is located at the intermediate position of the cingulum in the dorsal side, whereas that of C. polykrikoides is situated immediately beneath the cingulum. LSU rDNA phylogenies indicated that C. fulvescens is clearly distinct from, but closely related to C. polykrikoides among dinoflagellates.     

Description of a New Freshwater Ciliate Epistylis wuhanensis n. sp. (Ciliophora,Peritrichia) from China,with a Focus on Phylogenetic Relationships within Family Epistylididae

Two populations of Epistylis wuhanensis n. sp., a new freshwater peritrich ciliate, were isolated from different freshwater ponds located in Hubei, China. Their morphological characteristics were investigated using live observation, protargol impregnation, and scanning electron microscopy (SEM). Specimens from the two populations showed identical arrangement of the infraciliature and identical small subunit ribosomal RNA (SSU rRNA) gene and ITS1‐5.8S‐ITS2 sequences. The zooids present bell‐shaped and 90–175 × 27–54 μm in vivo. Macronucleus is variable in shape and located in the middle of cell. Pellicle is usually smooth with 139–154 and 97–105 striations above and below the trochal band, respectively. SSU rRNA gene and ITS1‐5.8S‐ITS2 sequences of E. wuhanensis n. sp. did not match any available sequences in GenBank. Phylogenetically, E. wuhanensis n. sp. clusters with the other Epistylis within the family Epistylididae, but is distinct from the major clades of Epistylis. Above all, the morphological characteristics and molecular analyses support that the present Epistylis is a new species. Expanded phylogenetic analyses of sessilids based on both SSU rRNA gene sequences and ITS1‐5.8S‐ITS2 sequences reveal that the genus Epistylis consists of Epistylis morphospecies and taxonomic revision of the genus is needed.     

A phylogenetic assessment of the colonisation patterns in <Emphasis Type="Italic">Spauligodon atlanticus</Emphasis> Astasio-Arbiza et al., 1987 (Nematoda: Oxyurida: Pharyngodonidae), a parasite of lizards of the genus <Emphasis Type="Italic">Gallotia</Emphasis> Boulenger: no simple answers

Parasite taxonomy traditionally relies on morphometric and life-cycle characteristics which may not reflect complex phylogenetic relationships. However, genetic analyses can reveal cryptic species within morphologically described parasite taxa. We analysed the phylogenetic variation within the nematode Spauligodon atlanticus Astasio-Arbiza, Zapatero-Ramos, Ojeda-Rosas & Solera-Puertas, 1987, a parasite of the Canarian lizard genus Gallotia Boulenger, inferring the origin of their current association. We also attempted to determine its relationship with other Spauligodon spp. Three different markers, mitochondrial COI plus nuclear 18S and 28S ribosomal RNA, were used to estimate the evolutionary relationships between these nematodes. S. atlanticus was found to be paraphyletic, suggesting that Gallotia spp. were colonised by two independent lineages of Spauligodon. Additional analyses of other Spauligodon spp. are required for a more complete interpretation of the evolution of this genus from the Canarian archipelago and its closest taxa. Our results emphasise the importance of extensive sampling and phylogenetic studies at the intrageneric level, and highlight the limitations of a morphologically based taxonomy in these parasites.     

Phylogeny of Rhigonematomorpha based on the complete mitochondrial genome of Rhigonema thysanophora (Nematoda: Chromadorea)

We determined the complete mitochondrial genome sequence of Rhigonema thysanophora, the first representative of Rhigonematomorpha, and used this sequence along with 57 other nematode species for phylogenetic analyses. The R. thysanophora mtDNA is 15 015 bp and identical to all other chromadorean nematode mtDNAs published to date in that it contains 36 genes (lacking atp8) encoded in the same direction. Phylogenetic analyses of nucleotide and amino acid sequence data for the 12 protein‐coding genes recovered Rhigonematomorpha as the sister group to the heterakoid species, Ascaridia columbae (Ascaridomorpha). The organization of R. thysanophora mtDNA resembles the most common pattern for the Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha clade in gene order, but with some substantial gene rearrangements. This similarity in gene order is in agreement with the sequence‐based analyses that indicate a close relationship between Rhigonematomorpha and Rhabditomorpha+Ascaridomorpha+Diplogasteromorpha. These results are consistent with certain analyses of nuclear SSU rDNA for R. thysanophora and some earlier classification systems that asserted phylogenetic affinity between Rhigonematomorpha and Ascaridomorpha, but inconsistent with morphology‐based phylogenetic hypotheses that suggested a close (taxonomic) relationship between rhigonematomorphs and oxyuridomorphs (pinworms). These observations must be tempered by noting that few rhigonematomorph species have been sequenced and included in phylogenetic analyses, and preliminary studies based on SSU rDNA suggest the group is not monophyletic. Additional mitochondrial genome sequences of rhigonematids are needed to characterize their phylogenetic relationships within Chromadorea, and to increase understanding of mitochondrial genome evolution.     

The concept of genus within the family Phytoseiidae (Acari: Parasitiformes): historical review and phylogenetic analyses of the genus Neoseiulus Hughes

Systematic studies on the family Phytoseiidae were first conducted at the beginning of the 20^th century but increased greatly after the Second World War. Various classifications have been proposed based on different characters such as: dorsal, ventral, and leg chaetotaxy; the shape of ventrianal and sternal shields; the shape of the insemination apparatus (spermatheca) and spermatodactylus; the number of teeth on the movable digit of chelicera; and dorsal and ventral adenotaxy. The genus concepts developed over the last five decades can be divided into two main categories or hypotheses. The first, supported mainly by Chant and McMurtry, focuses on dorsal and ventral chaetotaxy, and the genera so defined usually include a great number of species. The second category, proposed by Athias‐Henriot, considers the shape of the insemination apparatus as the key character, and the genera so defined usually include a limited number of species. From a diagnostic point of view, both classifications have a valid structure, but the question investigated herein was: which of the two classifications or hypotheses fits phylogenetic evolution? To answer this, we conducted molecular phylogenetic analyses (using the genes ITS and 12S rRNA) on the genus Neoseiulus, which has been subjected to classification based on the two main genus concepts. The results showed that the first hypothesis (Chant and McMurtry) leads to polyphyly of the genus Neoseiulus, while the second (Athias‐Henriot) leads to paraphyly of the genus. The results show that acarologists who first decided that the insemination apparatus was of evolutive importance could be correct as the shape of the insemination apparatus seems to better fit evolutive clades than dorsal and ventral chaetotaxy. The morphology of this organ, however, must be more accurately studied to better define homologies. The present paper investigates the two main hypotheses proposed until now for classification of Phytoseiidae and thereby opens the way for improved classification. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 253–273.     

Phylogeny,taxonomy, and evolution of Neotropical cichlids (Teleostei: Cichlidae: Cichlinae)

Despite recent progress on the higher‐level relationships of Cichlidae and its Indian, Malagasy, and Greater Antillean components, conflict and uncertainty remain within the species‐rich African, South American, and Middle American assemblages. Herein, we combine morphological and nucleotide characters from the mitochondrial large ribosomal subunit, cytochrome c oxidase subunit I, NADH dehydrogenase four, and cytochrome b genes and from the nuclear histone H3, recombination activating gene two, Tmo‐4C4, Tmo‐M27, and ribosomal S7 loci to analyse relationships within the Neotropical cichlid subfamily Cichlinae. The simultaneous analysis of 6309 characters for 90 terminals, including representatives of all major cichlid lineages and all Neotropical genera, resulted in the first well‐supported and resolved generic‐level phylogeny for Neotropical cichlids. The Neotropical subfamily Cichlinae was recovered as monophyletic and partitioned into seven tribes: Astronotini, Chaetobranchini, Cichlasomatini, Cichlini, Geophagini, Heroini, and Retroculini. Chaetobranchini + Geophagini (including the “crenicichlines”) was resolved as the sister group of Heroini + Cichlasomatini (including Acaronia). The monogeneric Astronotini was recovered as the sister group of these four tribes. Finally, a clade composed of Cichlini + Retroculini was resolved as the sister group to all other cichlines. The analysis included the recently described ?Proterocara argentina, the oldest known cichlid fossil (Eocene), which was placed in an apical position within Geophagini, further supporting a Gondwanan origin for Cichlidae. These phylogenetic results were used as the basis for generating a monophyletic cichline taxonomy. © The Willi Hennig Society 2008.     

Phylogenetic relationships, diversification and biogeography in Neotropical Brotogeris parakeets

Aim We present a molecular phylogenetic analysis of Brotogeris (Psittacidae) using several distinct and complementary approaches: we test the monophyly of the genus, delineate the basal taxa within it, uncover their phylogenetic relationships, and finally, based on these results, we perform temporal and spatial comparative analyses to help elucidate the historical biogeography of the Neotropical region. Location Neotropical lowlands, including dry and humid forests. Methods Phylogenetic relationships within Brotogeris were investigated using the complete sequences of the mitochondrial genes cyt b and ND2, and partial sequences of the nuclear intron 7 of the gene for Beta Fibrinogen for all eight species and 12 of the 17 taxa recognized within the genus (total of 63 individuals). In order to delinetae the basal taxa within the genus we used both molecular and plumage variation, the latter being based on the examination of 597 skin specimens. Dates of divergence and confidence intervals were estimated using penalized likelihood. Spatial and temporal comparative analyses were performed including several closely related parrot genera. Results Brotogeris was found to be a monophyletic genus, sister to Myiopsitta. The phylogenetic analyses recovered eight well‐supported clades representing the recognized biological species. Although some described subspecies are diagnosably distinct based on morphology, there was generally little intraspecific mtDNA variation. The Amazonian species had different phylogenetic affinities and did not group in a monophyletic clade. Brotogeris diversification took place during the last 6 Myr, the same time‐frame as previously found for Pionus and Pyrilia. Main conclusions The biogeographical history of Brotogeris implies a dynamic history for South American biomes since the Pliocene. It corroborates the idea that the geological evolution of Amazonia has been important in shaping its biodiversity, argues against the idea that the region has been environmentally stable during the Quaternary, and suggests dynamic interactions between wet and dry forest habitats in South America, with representatives of the Amazonian biota having several independent close relationships with taxa endemic to other biomes.     

The complete mitogenome of the Formosan termite, Coptotermes formosanus Shiraki

The Formosan termite Coptotermes formosanus Shiraki is a well-known invasive pest that causes severe damage to wooden structures in many parts of the world. Although several studies examined its phylogeographic patterns using a few mitochondrial genes, the phylogenetic relationships among C. formosanus are poorly understood because of the small number of mutations known among its mitochondrial genes. To provide a useful genetic tool for further analyses, we analyzed the complete mitochondrial genome sequence of C. formosanus using specimens collected from three isolated islands in the Ryukyu Archipelago of Japan. The circular mitogenome of these termites consisted of genes encoding 22 transfer RNAs, two ribosomal RNAs, and 13 mitochondrial proteins, as is the case for most animal mitochondrial genomes. The G + C content was 34.1%, and the total length varied slightly between 16,234 and 16,236 base pairs. The complete mitochondrial genomes of the three populations were more than 99.9% identical to each other and showed differences at six nucleotide positions. The COII, 12S rRNA, and 16S rRNA genes that are commonly used for phylogenetic analyses revealed only one substitution or no substitutions. The mitogenome sequences determined here should contribute to the design of new molecular markers for the clarification of the historical distribution process of C. formosanus and for further phylogenetic analyses with this and related termite species.     

Molecular phylogenetics provides a novel hypothesis of chromosome evolution in Neotropical fishes of the genus Potamorhina (Teleostei,Curimatidae)

Potamorhina includes the largest species in the Neotropical fish family Curimatidae. They perform long-distance migrations in large schools and represent relative importance for regional fisheries in South American lowlands. A morphology-based phylogenetic study recognized five species and proposed interspecific phylogenetic relationships mostly based on osteology, squamation, and morphology of the gasbladder. Subsequent cytogenetic studies revealed extreme variability in diploid numbers and other cytomolecular structures and hypothesized multiple events of chromosome rearrangements with centric fissions followed by reversed fusions. However, neither the taxonomic revision and phylogeny nor the cytogenetic hypothesis of chromosome evolution in Potamorhina was tested using molecular phylogenetic approaches. Here, we use mitochondrial and nuclear DNA sequences to delimit species of Potamorhina with an extensive sampling across the Amazon basin and use phylogenetic methods to test prior hypothesis of multiple events of chromosome rearrangements during the evolution of the genus. Phylogenetic and species delimitation methods clearly support the presence of five species but reveal novel interspecific relationships allowing a reinterpretation of the morphological characters relative to the number of vertebrae, caudal peduncle pigmentation, and modifications in the gasbladder chambers. With the new phylogenetic arrangement, we propose a novel hypothesis of occurrence of a single chromosome fission in the lineage of P. latior followed by an extraordinary event that involved more than 20 chromosome-pair fissions during the evolution of the ancestor of P. altamazonica and P. squamoralevis. This novel hypothesis represents a simpler and more conceivable explanation for the achievement of these elevated chromosome numbers during the evolution of Potamorhina.