Parentage analysis in Gabonese colonies of soil-feeding termites belonging to the Cubitermes sp. affinis subarquatus complex of species (Termitidae: Termitinae)

Abstract Cubitermes spp. are widely distributed soil-feeding termite species in sub-Saharan Africa which play a fundamental role in soil structure and fertility. A complex of at least four cryptic species (i.e., Cubitermes sp. affinis subarquatus complex of species) has been recently described using molecular markers. In order to investigate the breeding system of these species, five microsatellite markers were used to carry out parentage and relatedness analyses in 15 Gabonese colonies. Monogamy was confirmed as the predominant reproductive organization in Cubitermes spp. (76% of the colonies). Within 30% of these monogamous colonies, a high relatedness between reproductives was shown, suggesting that mating between related individuals occurs. However, Cubitermes colonies can deviate from monogamy. Indeed, parental contributions by at least two related reproductives of the same sex were revealed in four colonies and polyandry was demonstrated in two of them. Infiltration of reproductives in the colony is the most plausible explanation for such cases of polygamy in Cubitermes spp.     

Genetic differentiation in the soil-feeding termite Cubitermes sp. affinis subarquatus : occurrence of cryptic species revealed by nuclear and mitochondrial markers

Background  

Soil-feeding termites are particularly interesting models for studying the effects of fragmentation, a natural or anthropic phenomenon described as promoting genetic differentiation. However, studying the link between fragmentation and genetics requires a method for identifying species unambiguously, especially when morphological diagnostic characters are lacking. In humivorous termites, which contribute to the fertility of tropical soils, molecular taxonomy and phylogenetic relationships are rarely studied, though mitochondrial and nuclear molecular markers are widely used in studies of pest termites. Here, we attempt to clarify the taxonomy of soil-feeding colonies collected throughout the naturally fragmented Lopé Reserve area (Gabon) and morphologically affiliated to Cubitermes sp. affinis subarquatus. The mitochondrial gene of cytochrome oxidase II (COII), the second nuclear rDNA internal transcribed spacer (ITS2) and five microsatellites were analyzed in 19 colonies.     

Characterization of two sulfate-reducing bacteria from the gut of the soil-feeding termite,Cubitermes speciosus

Two sulfate-reducing bacteria (SRB) were isolated from a mixed culture enriched with benzoate obtained from gut homogenate of the soil-feeding higher termite, Cubitermes speciosus. The organisms were vibrioid rods, staining Gram-negative, which performed incomplete substrate oxidation. They differed in several features. The smaller one, strain STp, was motile with a single polar flagellum. This strain differed from Desulfovibrio desulfuricans only by its inability to oxidize malate and pentanol. The bigger one, strain STg, differed from Desulfovibrio giganteus only by its nonmotility and a lower length. It is the first evidence of the presence of SRB in termite gut.     

Mitochondrial phylogenies in the light of pseudogenes and Wolbachia: re-assessment of a bark beetle dataset

Phylogenetic studies based on mtDNA become increasingly questioned because of potential pitfalls due to mitochondrial pseudogenes and mitochondrial selective sweeps. While the inclusion of nuclear markers should preferentially be considered for future studies, there is no need to abandon mtDNA as long as tests for the known mtDNA artefacts are performed. In this study we presentadditionaldata and test previous phylogeographical studies of Pityogenes chalcographus. We did not detect nuclear copies (numts) of the previously used mitochondrial markers by performing a combined long range/nested PCR of the COI gene and by an in silico analysis of the COI sequence data. This confirms the robustness of our previous phylogenetic study of Pityogenes chalcographus. Results of an in-situ hybridization of Wolbachia in Pityogenes chalcographus confirm the presence of this endosysmbiont in this species. However, we did not detect a correlation between infection status, geographical region and mtDNA haplotypes. The hybridisation data also support a previous hypothesis that infections do not result from parasitoids or parasitic nematodes, insect surface or laboratory contaminations and are hence a true infection of Pityogenes chalcographus. We conclude that the deep structure found in mitochondrial populations of Pityogenes chalcographus indeed represents the evolutionary history of European populations.     

Phylogenomics and multigene phylogenies decipher two new cryptic marine algae from California,Gelidium gabrielsonii and G. kathyanniae (Gelidiales,Rhodophyta)

Molecular surveys are leading to the discovery of many new cryptic species of marine algae. This is particularly true for red algal intertidal species, which exhibit a high degree of morphological convergence. DNA sequencing of recent collections of Gelidium along the coast of California, USA, identified two morphologically similar entities that differed in DNA sequence from existing species. To characterize the two new species of Gelidium and to determine their evolutionary relationships to other known taxa, phylogenomic, multigene analyses, and morphological observations were performed. Three complete mitogenomes and five plastid genomes were deciphered, including those from the new species candidates and the type materials of two closely related congeners. The mitogenomes contained 45 genes and had similar lengths (24,963–24,964 bp). The plastid genomes contained 232 genes and were roughly similar in size (175,499–177,099 bp). The organellar genomes showed a high level of gene synteny. The two Gelidium species are diminutive, turf‐forming, and superficially resemble several long established species from the Pacific Ocean. The phylogenomic analysis, multigene phylogeny, and morphological evidence confirms the recognition and naming of two new species, describe herein as G. gabrielsonii and G. kathyanniae. On the basis of the monophyly of G. coulteri, G. gabrielsonii, G. galapagense, and G. kathyanniae, we suggest that this lineage likely evolved in California. Organellar genomes provide a powerful tool for discovering cryptic intertidal species and they continue to improve our understanding of the evolutionary biology of red algae and the systematics of the Gelidiales.     

Phylogenetic relationships among species of Pichia, Issatchenkia and Williopsis determined from multigene sequence analysis, and the proposal of Barnettozyma gen. nov., Lindnera gen. nov. and Wickerhamomyces gen. nov

Relationships among species assigned to the yeast genera Pichia, Issatchenkia and Williopsis , which are characterized by the ubiquinone CoQ-7 and inability to utilize methanol, were phylogenetically analyzed from nucleotide sequence divergence in the genes coding for large and small subunit rRNAs and for translation elongation factor-1α. From this analysis, the species separated into five clades. Species of Issatchenkia are members of the Pichia membranifaciens clade and are proposed for transfer to Pichia . Pichia dryadoides and Pichia quercuum are basal members of the genus Starmera . Williopsis species are dispersed among hat-spored taxa in each of the remaining three clades, which are proposed as the new genera Barnettozyma, Lindnera and Wickerhamomyces . Lineages previously classified as varieties of Pichia kluyveri , ' Issatchenkia ' scutulata, Starmera amethionina and ' Williopsis ' saturnus are elevated to species rank based on sequence comparisons.     

A new species of open-air processional column termite,Hospitalitermes nigriantennalis sp. n. (Termitidae), from Borneo

A new species of open-air processional column termite is here described based on the soldier and worker castes from eight colonies in north Barito, central Kalimantan. Hospitalitermes nigriantennalis sp. n. is readily distinguished in the field from related Hospitalitermes spp. by the light brown to orangish coloration of the soldier head capsule that, further, is with vertex yellowish and nasus brownish. The soldier antenna and the maxillary and labial palps are blackish. By contrast, soldiers from other species of Hospitalitermes from this region have a uniformly black head capsule and antennae. Finally, Hospitalitermes nigriantennalis sp. n. has a minute indentation in the middle of the posterior part of head capsule, which further helps to differentiate this new species from other Hospitalitermes from the Indo-Malayan and Austro-Malayan regions.     

Biecheleria tirezensis sp. nov. (Dinophyceae,Suessiales), a new halotolerant dinoflagellate species isolated from the athalassohaline Tirez natural pond in Spain

A new euryhaline and eurythermal dinoflagellate species, Biecheleria tirezensis sp. nov., is described based on samples taken from an extreme environment, the athalassohaline and particularly sulphate-rich Tirez natural pond (Spain). This species is able to survive in salinities from almost fresh water up to 56 and over a 5–25°C temperature range. Thus, the ecological characteristics of this isolate differentiate it from other species of the same genus. Its morphology, as examined by light, scanning and transmission electron microscopy, shows that the cells are almost spherical, with several series of amphiesmal vesicles. It also has a single elongate amphiesmal vesicle (EAV) observed by SEM and the eyespot has a type E structure, typical of Biecheleria. Spherical and smooth cysts were observed in old cultures. The pigment composition is typical of a peridinin-containing dinoflagellate. Phylogeny inferred from nuclear rDNA SSU, ITS and LSU sequences showed the isolate belongs to the genus Biecheleria, closest to B. cincta and B. brevisulcata. Modelling and analysis of the secondary structure of its ITS2 region, and that of other species of the same genus and some representatives of the most closely related genera, indicated that the isolate represents a new species clearly separated from but related to B. cincta. The criterion of the presence of Compensatory Base Changes (CBCs) in the secondary structure of the ITS2 region as an indicator of species differentiation confirmed this, supporting the establishment of the Tirez pond isolate as a new species of Biecheleria.     

Clostridium mayombei sp. nov., an H2/CO2 acetogenic bacterium from the gut of the African soil-feeding termite,Cubitermes speciosus

Clostridium mayombei sp. nov., a previously undescribed H₂-oxidizing CO₂-reducing acetogenic bacterium, was isolated from gut contents of the African soilfeeding termite, Cubitermes speciosus. Cells were anaerobic, Gram positive, catalase and oxidase negative, endospore-forming motile rods which measured 1×2 – 6 m and which had a DNA base composition of 25.6 mol% G+C (strain SFC-5). Optimum conditions for growth on H₂+CO₂ were at 33°C and pH 7.3, and under these conditions cells produced acetate according to the equation: 4 H₂+2 CO₂CH₃COOH+2 H₂O. Other substrates supporting good growth included carbohydrates (e.g. glucose, xylose, starch), sugar alcohols, and organic and amino acids, and with these substrates acetate was almost always the principle fermentation product. Comparative analysis of 16S rRNA nucleotide sequences confirmed that C. mayombei was closely related to various members of the genus Clostridium. However, morphological and physiological differences between C. mayombei and other homoacetogenic clostridia were deemed significant enough to warrant creation of a new taxon. Results are discussed in light of the diversity of H₂/CO₂ acetogens recently isolated from various termites, and in terms of the relative importance of H₂/CO₂ acetogenesis to termite nutrition.     

Molecular phylogeny of Pacific Archigregarines (Apicomplexa), including descriptions of Veloxidium leptosynaptae n. gen., n. sp., from the sea cucumber Leptosynapta clarki (Echinodermata), and two new species of Selenidium

Although archigregarines are poorly understood intestinal parasites of marine invertebrates, they are critical for understanding the earliest stages in the evolution of the Apicomplexa. Previous studies suggest that archigregarines are a paraphyletic stem group from which other lineages of gregarines, and possibly all other groups of apicomplexans, evolved. However, substantiating this inference is difficult because molecular phylogenetic data from archigregarines, in particular, and other gregarines, in general, are severely limited. In an attempt to help fill gaps in our knowledge of archigregarine diversity and phylogeny, we set out to discover and characterize novel lineages of archigregarines with high-resolution light and scanning electron microscopy and analyses of small subunit (SSU) rDNA sequences derived from single-cell (SC) PCR techniques. Here, we describe two novel species of Selenidium, namely Selenidium idanthyrsae n. sp. and S. boccardiellae n. sp., and demonstrate the surface morphology and molecular phylogenetic position of the previously reported species S. cf. mesnili. We also describe a novel genus of archigregarine, Veloxidium leptosynaptae n. gen., n. sp., which branches with an environmental sequence and, together, forms the nearest sister lineage to a diverse clade of marine eugregarines (i.e. lecudinids and urosporids). This molecular phylogenetic result is consistent with the hypothesis that archigregarines are deeply paraphyletic within apicomplexans, and suggests that convergent evolution played an important role in shaping the diversity of eugregarine trophozoites.     

Ostreopsis fattorussoi sp. nov. (Dinophyceae), a new benthic toxic Ostreopsis species from the eastern Mediterranean Sea

The new benthic toxic dinoflagellate, Ostreopsis fattorussoi sp. nov., is described from the Eastern Mediterranean Sea, Lebanon and Cyprus coasts, and is supported by morphological and molecular data. The plate formula, Po, 3′, 7″, 6c, 7s, 5?, 2′′′′, is typical for the Ostreopsis genus. It differs from all other Ostreopsis species in that (i) the curved suture between plates 1′ and 3′ makes them approximately hexagonal, (ii) the 1′ plate lies in the left half of the epitheca and is obliquely orientated leading to a characteristic shape of plate 6″. The round thecal pores are bigger than the other two Mediterranean species (O. cf. ovata and O. cf. siamensis). O. fattorussoi is among the smallest species of the genus (DV: 60.07 ± 5.63 μm, AP: 25.66 ± 2.97 μm, W: 39.81 ± 5.05 μm) along with O. ovata. Phylogenetic analyses based on the LSU and internal transcribed spacer rDNA shows that O. fattorussoi belongs to the Atlantic/Mediterranean Ostreopsis spp. clade separated from the other Ostreopsis species. Ostreopsis fattorussoi produces OVTX‐a and structural isomers OVTX‐d and ‐e, O. cf. ovata is the only other species of this genus known to produce these toxins. The Lebanese O. fattorussoi did not produce the new palytoxin‐like compounds (ovatoxin‐i, ovatoxin‐j₁, ovatoxin‐j₂, and ovatoxin‐k) that were previously found in O. fattorussoi from Cyprus. The toxin content was in the range of 0.28–0.94 pg · cell^?1. On the Lebanon coast, O. fattorussoi was recorded throughout the year 2015 (temperature range 18°C–31.5°C), with peaks in June and August.     

A new species of Ceylonitermellus Emerson, 1960 (Blattodea: Termitidae: Nasutitermitinae) from India with a key to the genus

Ceylonitermellus Emerson is a rarely collected soil inhabiting nasute termite endemic to Oriental region with three known species. A fourth species, Ceylonitermellus sahyadriensis sp. nov. is described and illustrated based on morphological characters of soldier and gut morphology of workers. Both the castes have poorly sclerotized body and paler in colour. This is the second species from India and fourth species of the genus from world. The species can be distinguished from the closely related C. periyarensis by the pyriform and shorter head capsule and with other two species of the genus by its larger head capsule as compared to C. kotuae and smaller head capsule as compared to C. hantanae. The new species was collected from tropical evergreen forest from a small colony near the base of a tree.LSID: urn:lsid:zoobank.org:pub:34616357-2CC9-46B2-8B8D-3CFD984CED89.     

Bensingtonia pseudonaganoensis sp. nov., a novel ballistoconidium-forming yeast species isolated from plant leaves

Among the basidiomycetous yeasts isolated from plant leaves collected in different regions of China, two ballistoconidium-forming strains were revealed to represent an undescribed species of the genus Bensingtonia by conventional, chemotaxonomic and molecular phylogenetic characterization. Sequence analysis of the 26S rDNA D1/D2 domains and the internal transcribed spacer (ITS) region indicated that the novel species was located in the Agaricostilbum lineage and closely related to Bensingtonia naganoensis and Bensingtonia ciliata, with the former as its closest relative. The name Bensingtonia pseudonaganoensis sp. nov. is proposed (type strain: AS 2.2601^T = CBS 10121^T)     

Molecular phylogeny of Fusarium oxysporum species complex isolated from agricultural soils in Iran

Abstract

Members of Fusarium oxysporum species complex (FOSC) are economically most important plant pathogenic fungi. Until now, the classification of FOSC members in Iran is not well described. So, the objective of the current research was to study the phylogenetic diversity of FOSC strains recovered from agricultural soils in Iran. A total of 45 isolates belonging to the FOSC were recovered from agricultural soils in Iran. The identification of the members of F. oxysporum f. sp. vasinfectum (Fov) and F. oxysporum f. sp. ciceris (Foc) was confirmed molecularly using Fov-eg-f/Fov-eg-r and Foc0-12f/Foc0-12r primers, respectively. F. redolens isolates were distinguished from other FOSC using Redolens-F/Redolens-R primers. Comparisons of DNA sequence data from a portion of the tef1 gene revealed all isolates belonged to Fov, Foc, F. commune and F. redolens. This is the first in-depth report on molecular identification of FOSC and related species isolated from agricultural soils in Iran.     

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

A novel species of aseptate eugregarine, Ganymedes yurii sp. n., is described using microscopic and molecular approaches. It inhabits the intestine of Gondogeneia sp., a benthic amphipod found along the shore of James Ross Island, Weddell Sea, Antarctica. The prevalence of the infection was very low and only a few caudo‐frontal syzygies were found. Morphologically, the new species is close to a previously described amphipod gregarine, Ganymedes themistos, albeit with several dissimilarities in the structure of the contact zone between syzygy partners, as well as other characteristics. Phylogenetic analysis of the 18S rDNA from G. yurii supported a close relationship between these species. These two species were grouped with other gregarines isolated from crustaceans hosts (Cephaloidophoroidea); however, statistical support throughout the clade of Cephaloidophoroidea gregarines was minimal using the available dataset.     

First report of three Kudoa species from eastern Australia: Kudoa thyrsites from mahi mahi (Coryphaena hippurus), Kudoa amamiensis and Kudoa minithyrsites n. sp. from sweeper (Pempheris ypsilychnus)

Fish species around the world are parasitized by myxozoans of the genus Kudoa, several of which infect and cause damage of commercial importance. In particular, Kudoa thyrsites and Kudoa amamiensis infect certain cultured fish species causing damage to muscle tissue, making the fish unmarketable. Kudoa thyrsites has a broad host and geographic range infecting over 35 different fish species worldwide, while K. amamiensis has only been reported from a few species in Japanese waters. Through morphological and molecular analyses we have confirmed the presence of both of these parasites in eastern Australian waters. In addition, a novel Kudoa species was identified, having stellate spores, with one polar capsule larger than the other three. The SSU rDNA sequence of this parasite was 1.5% different from K. thyrsites and is an outlier from K. thyrsites representatives in a phylogenetic analysis. Furthermore, the spores of this parasite are distinctly smaller than those of K. thyrsites, and thus it is described as Kudoa minithyrsites n. sp. Although the potential effects of K. minithyrsites n. sp. on its fish hosts are unknown, both K. thyrsites and K. amamiensis are associated with flesh quality problems in some cultured species and may be potential threats to an expanding aquaculture industry in Australia.     

Lunachloris lukesovae gen. et sp. nov. (Trebouxiophyceae,Chlorophyta), a novel coccoid green alga isolated from soil in South Bohemia,Czech Republic

Culture collections of microorganisms can still hold undiscovered biodiversity; with molecular techniques, considerable progress has been made in characterizing microalgae which were isolated in the past and misidentified due to a lack of morphological features. However, many strains are still awaiting taxonomic reassessment. Here we analysed the phylogenetic position, morphology and ultrastructure of the strain CCALA 307 previously identified as Coccomyxa cf. gloeobotrydiformis Reysigl isolated in 1987 from field soil in South Bohemia, Czech Republic. Molecular phylogenetic analyses based on SSU rDNA and the plastid rbcL gene revealed that the strain CCALA 307 formed a distinct sister lineage to Neocystis and Prasiola clades within the Trebouxiophyceae. We describe this strain as a new genus and species, Lunachloris lukesovae. Multiple conserved nucleotide positions identified in the secondary structures of the highly variable ITS2 rDNA barcoding marker provide further evidence of the phylogenetic position of Lunachloris. Minute vegetative cells of this newly recognized species are spherical or ellipsoid, with a single parietal chloroplast without a pyrenoid. Asexually, it reproduces by the formation of 2–6 autospores. Since the majority of recent attention has been paid to algae from the tropics or extreme habitats, the biodiversity of terrestrial microalgae in temperate regions is still notably unexplored and even a ‘common’ habitat like agricultural soil can contain new, as yet unknown species. Moreover, this study emphasizes the importance of culture collections of microorganisms even in the era of culture-independent biodiversity research, because they may harbour novel and undescribed organisms as well as preserving strains for future studies.     

Chroniodiplogaster formosiana sp. n. (Rhabditida: Diplogastridae) from Chinese populations of Odontotermes formosanus Shiraki (Isoptera: Termitidae)

Chroniodiplogaster formosiana sp. n. (Rhabditida: Diplogastridae) is described from a population of Odontotermes formosanus Shiraki (Isoptera: Termitidae) collected from dead (unidentified) wood at Dinghu Park, China. Characters of C. formosiana which separate it from C. aerivora (Cobb) are a longer tail, the presence of four micropapillae (quadriform condition), and the adjacent position of the second and third macropapillae on the male tail. The diplogasterid Pristionchus uniformis Fedorko & Stanuszek, which is transferred to Chroniodiplogaster, can be distinguished from both C. formosiana and C. aerivora by the position of its excretory pore. Variable results in experimental infection trials suggest that some still unknown factor or factors are important in the infection process. Further studies are necessary to better define these factors before C. formosiana can be considered as a biological control agent of the Formosan termite.     

Multigene phylogenetic analysis of the Trichomonascus, Wickerhamiella and Zygoascus yeast clades, and the proposal of Sugiyamaella gen. nov. and 14 new species combinations

Relationships among species assigned to the ascosporic yeast genera Sporopachydermia, Stephanoascus, Trichomonascus, Wickerhamiella and Zygoascus, and to the associated anamorphic genera Arxula, Blastobotrys, Sympodiomyces and Trigonopsis, were determined from phylogenetic analyses of gene sequences from the nearly complete large-subunit rRNA gene, the mitochondrial small-subunit rRNA gene, and cytochrome oxidase II. The genus Stephanoascus is polyphyletic, resulting in reassignment of two species to the older genus Trichomonascus and the third to Sugiyamaella gen. nov. (type species Sugiyamaella smithiae). The genera Sporopachydermia, Wickerhamiella and Zygoascus appear to be monophyletic. The species Pichia ofunaensis and P. tannicola are proposed for transfer to Zygoascus. Arxula, Blastobotrys and Sympodiomyces are members of the Trichomonascus clade, with the genus Blastobotrys having taxonomic priority for anamorphic states. Trigonopsis variabilis and three species of Candida represent a distinct clade. From the foregoing gene sequence analyses, the new ascosporic genus Sugiyamaella is proposed, as are 14 new species combinations and the new family Trichomonascaceae.