Large Subunit Ribosomal DNA Sequences Research Articles

Morphological and molecular characterization of Ektaphelenchoides pini (Massey, 1966) Baujard, 1984 (Aphelenchoididae; Ektaphelenchinae) from Iran, with morphological and taxonomic observations on some species

Ektaphelenchoides pini, the type species of the genus Ektaphelenchoides, was recovered from wood and bark samples of a dead broadleaf forest tree collected from the forests of Golestan province in north of Iran. The recovered population is mainly characterized by massive wide spicules of males with well-developed condylus marked by indentations at the apex and simple distal tip. It was further characterized by 756 to 947 μm long females having a cephalic region slightly separated from the rest body by a shallow depression, 20 to 23 μm stylet with wide lumen lacking conophore and knobs, excretory pore (E pore) at about one metacorpus length behind it, or 92 to 106 μm from anterior end and hemizonid just posterior to it, vagina anteriorly inclined, post uterine sac (PUS) ca 1.2 times vulval body width long, posterior body region elongate conoid, ending to a filiform tip, no functional rectum, a vestigial anus and common males with dorsally convex tail ending to an elongate spike and two pairs of precloacal (P2) and caudal (P3) large papillae at 5 to 6 μm distance anterior to cloacal opening and 30 to 41% of tail, respectively and lacking the single precloacal papilla (P1). In molecular phylogenetic analyses using small and large subunit ribosomal DNA (SSU, LSU rDNA) sequences, the Iranian population of E. pini fell in a clade including species of three genera Ektaphelenchus, Ektaphelenchoides, and Devibursaphelenchus in SSU, and a clade including species of Ektaphelenchus and Ektaphelenchoides in LSU tree, in close association with an isolate identified as E. pini in the latter phylogeny with high (0.99) Bayesian posterior probability (BPP). The comparisons with the type and French populations, as well as phylogenetic affinities of the species using ribosomal data, are discussed. This is the first report of E. pini from Iran, and its first simultaneous morphological and molecular phylogenetic study. New observations on some species of the genus were also presented and discussed.

Determination of volatile organic compounds in the stinkhorn fungus Pseudocolus fusiformis in different stages of fruiting body formation

Abstract A stinkhorn fungus was collected from the mountainous area of Yoshida campus, Yamaguchi University, Japan. Morphological characterization and similarity of large subunit ribosomal DNA sequences identified the fungus as Pseudocolus fusiformis. MonoTrap™ was combined with gas chromatography-mass spectrometry (GC-MS) to identify volatile organic compounds (VOCs) emitted from the fungus harvested at different stages of maturity. The main VOCs emitted from the mature fruiting body were 3-methyl-butanol, 4-methyl-phenol, and dimethyl tetrasulfide, while none of these compounds were detected in the egg-shaped state. Volatile sulfur-containing compounds, including dimethyl disulfide, trisulfide and tetrasulfide, which are commonly detected in stinkhorn fungi and truffles, were also emitted from this fungus. Furthermore, results elucidated that most VOCs occurred in the mature stage of Ps. fusiformis (fruiting body with arms fuse). This is the first study reporting VOC production of Ps. fusiformis.

Morphological and molecular identification of epibiontic sessilid Epistylis semiciculus n. sp. (ciliophora, Peritrichia) from Procambarus clarkia (Crustacea, Decapoda) in China.

Data on sessilinasis from Procambarus clarkia are limited. This study investigates sessilid diversity in Hubei Province, China in 2016. Procambarus clarkia pereopods were covered by two sessilid morphotypes in April and May, and the gills were adhered by one of these two morphotypes (morphotype I) in January. Identifying the two morphotypes according to their morphological characters through live observations and protargol-stained method is difficult. Both morphotypes show almost identical morphological characteristics: zooids present vase-shaped, the length-to-width ratio is 2:1, the semicircle-shaped peristomial disk is evidently above the peristomial lip, single contractile vacuole is located below the peristomial lip, and the oral infraciliature shows identical arrangement which can be distinguished from other Epistylis. However, the morphometric data of the two morphotypes are significant different: body size of morphotype I is 78.9–103.8 × 32.1–54.6 μm, whereas that of morphotypes II is 136.7–171.5 × 60.9–88.0 μm. To further identify the two morphotypes, molecular regions including small subunit ribosomal DNA (SSU rDNA) sequences, large subunit ribosomal DNA (LSU rDNA) sequences, and ITS1-5.8S-ITS2 sequences were used. Results supported that the two morphotypes are single species of genus Epistylis rather than distinct species based in their distinct size ranges and temporal presence events. We assigned it the name E. semiciculus n. sp. with respect to the semicircular peristomial disk. Overall, these findings emphasized the importance of using molecular data to solve the identification confusion caused by ontogenetic processes. This study is the first morphological and molecular characterization of a sessilid isolated from P. clarkia under aquaculture conditions.

Cryptic speciation in Protoceratium reticulatum (Dinophyceae): Evidence from morphological, molecular and ecophysiological data

The cosmopolitan, potentially toxic dinoflagellate Protoceratium reticulatum possesses a fossilizable cyst stage which is an important paleoenvironmental indicator. Slight differences in the internal transcribed spacer ribosomal DNA (ITS rDNA) sequences of P. reticulatum have been reported, and both the motile stage and cyst morphology of P. reticulatum display phenotypic plasticity, but how these morpho-molecular variations are related with ecophysiological preferences is unknown. Here, 55 single cysts or cells were isolated from localities in the Northern (Arctic to subtropics) and Southern Hemispheres (Chile and New Zealand), and in total 34 strains were established. Cysts and/or cells were examined with light microscopy and/or scanning electron microscopy. Large subunit ribosomal DNA (LSU rDNA) and/or ITS rDNA sequences were obtained for all strains/isolates. All strains/isolates of P. reticulatum shared identical LSU sequences except for one strain from the Mediterranean Sea that differs in one position, however ITS rDNA sequences displayed differences at eight positions. Molecular phylogeny was inferred using maximum likelihood and Bayesian inference based on ITS rDNA sequences. The results showed that P. reticulatum comprises at least three ribotypes (designated as A, B, and C). Ribotype A included strains from the Arctic and temperate areas, ribotype B included strains from temperate regions only, and ribotype C included strains from the subtropical and temperate areas. The average ratios of process length to cyst diameter of P. reticulatum ranged from 15% in ribotype A, 22% in ribotype B and 17% in ribotype C but cyst size could overlap. Theca morphology was indistinguishable among ribotypes. The ITS-2 secondary structures of ribotype A displayed one CBC (compensatory change on two sides of a helix pairing) compared to ribotypes B and C. Growth response of one strain from each ribotype to various temperatures was examined. The strains of ribotypes A, B and C exhibited optimum growth at 15 °C, 20 °C and 20–25 °C, respectively, thus corresponding to cold, moderate and warm ecotypes. The profiles of yessotoxins (YTXs) were examined for 25 strains using liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS). The parent compound yessotoxin (YTX) was produced by strains of ribotypes A and B, but not by ribotype C strains, which only produced the structural variant homoyessotoxin (homoYTX). Our results support the notion that there is significant intra-specific variability in Protoceratium reticulatum and the biogeography of the different ribotypes is consistent with specific ecological preferences.

Tryblidiopsis magnesii sp. nov. from Picea glauca in Eastern Canada.

Tryblidiopsis pinastri (Leotiomycetes, Rhytismatales) was described from Picea abies in Europe and was also thought to occur on North American Picea. However, previously published sequences of Picea foliar endophytes from Eastern Canada suggested the presence of at least two cryptic Tryblidiopsis species, distinct from T. pinastri and other known species. Our subsequent sampling of Tryblidiopsis ascomata from dead attached Picea glauca branches resulted in the collection of a putatively undescribed species previously isolated as a P. glauca endophyte. Morphological evidence combined with phylogenetic analyses based on nuclear ribosomal internal transcribed spacer (ITS) and large subunit ribosomal (LSU) DNA sequences support the distinctiveness of this species, described here as T. magnesii.

Morphological and molecular characterisation of Ektaphelenchoides tonekabonensis n. sp. (Rhabditida: Ektaphelenchinae) from northern Iran

Summary Ektaphelenchoides tonekabonensis n. sp. is described and illustrated based upon morphological, morphometric and molecular characters. The new species is characterised by 476-659 μm long females, lip region broad and continuous with body contour, two weak lateral bands barely visible in lateral view and cross section, needle-like stylet with its conus forming ca 50% of the total length and with a very narrow lumen in the shaft, excretory pore located just opposite the metacorpus base or slightly posterior, a dense (sclerotised) mass just anterior to the vagina, a short post-uterine sac 5-7 μm long, elongate conoid distal body region ending in a long filiform part, males common with a dorsally convex conical tail ending to a filiform tip, 7-8 μm long spicules with a small projection at the capitulum close to the condylus, its tip posteriorly bent, and five precloacal + caudal papillae. Based upon morphological similarities and phylogenetic affinities, it is similar to six known species of the genus, namely: E. attenuata, E. caspiensis, E. fuchsi, E. kelardashtensis, E. musae, and E. ruehmi. Ektaphelenchoides caspiensis is typologically most similar to the new species and can be separated based on vulval position, excretory pore position and male tail characters. The next most similar species, E. kelardashtensis, has a longer stylet and posteriorly located excretory pore. Comparisons with the other aforementioned species and typologically similar species under Seinura are also discussed. Molecular phylogenetic analyses were performed using Bayesian inference (BI) based upon two partial small and large subunit ribosomal DNA (SSU and LSU rDNA D2-D3) sequences and the phylogenetic affinities of the new species in both phylogenies were discussed.

Ultrastructure and phylogeny of a new species of mixotrophic dinoflagellate, Paragymnodinium stigmaticum sp. nov. (Gymnodiniales, Dinophyceae)

:A new dinoflagellate, Paragymnodinium stigmaticum Yokouchi, Onuma & Horiguchi sp. nov., was described from sand samples collected at Sumiyoshi beach, Sado Island, Niigata Prefecture, Japan, based on observations at the light, scanning and transmission electron microscope levels together with molecular characterisation. The cells were 8.5–15.2 μm long and 6.3–12.4 μm wide. The episome and hyposome were subequal and hemispherical; although, the episome could also be conical. The cingulum was wide, well excavated and descended one quarter to a half of its own width. The sulcus was straight and widened slightly as it reached the antapex. A slightly curved sulcal extension-like furrow (SEF) ran from the right end of cingulum toward the apex. Cells possessed five to 10 yellowish brown chloroplasts, a red eyespot and small nematocysts. The dinoflagellate ingested prey cells despite the possession of chloroplasts, indicating a mixotrophic mode of nutrition. Paragymnodinium stigmaticum shared many morphological features and nutritional strategies with a known species of the genus Paragymnodinium, Paragymnodinium shiwhaense, including the possession of nematocysts, small polygonal amphiesmal vesicles and a mixotrophic mode of nutrition. However, it is clearly distinguished from P. shiwhaense by its feeding mechanism, its chloroplast ultrastructure, the presence of an eyespot, the absence of a plate-like structure in the amphiesmal vesicles and a benthic lifestyle (P. shiwhaense is planktonic). A phylogenetic analysis inferred from concatenated small and large subunit ribosomal DNA sequences recovered P. stigmaticum in a robust clade with P. shiwhaense that was included in the clade Gymnodinium sensu stricto. Therefore, it is reasonable to conclude that this dinoflagellate from Japan is a new species in the genus Paragymnodinium.

Taxonomic Approach for Species Diversity of Yeasts and Yeasts-like Fungi through D1/D2 Region of Large Subunit Ribosomal DNA Sequences

The identification of yeasts or yeasts-like fungi and verify their diversity are principal aspect for bioindustry and ecosystem sustainability. Taxonomic approach provides identification tool to ensure the taxonomic position of yeasts and yeasts-like fungi which definitely set to utilization concerns. The aim of this study is to understanding the taxonomic position of yeasts and yeasts-like fungi from the distinctive of its sequences relationship. Yeasts and yeasts-like fungi strains were isolated through various culture dependent methods from natural resources samples of Karimun Besar Island, Province of Riau Islands, Indonesia. The identification process was performed through amplifying the accurate DNA-based in D1/D2 region of large subunit (26S) ribosomal DNA. As the result, a total of 85 isolates of yeasts and yeasts-like fungi were obtained with 16 closest related taxa through phylogenetic tree construction. Ascomycetous was the predominating group representing 91% of the total isolates sequences followed by Basidiomycetous (8%) and Zygomycetous (1%). The black yeasts (yeasts-like) known as Aureobasidium melanogenum was predominant species with represent to 54% of total isolates and present in particular habitat. Taxonomically, there are six isolates are represent to be novel taxa candidates which pretend to enhance genetic resources of yeasts and yeasts-like fungi especially from Indonesia. In addition, this information provides specific technique to reach specific yeasts or yeasts-like fungi species in nature by managing the sample collection and culture methods.

Adenoides sinensis, a new sand-dwelling dinoflagellate species from China and reexamination of Adenoides eludens from an Atlantic strain

:The sand-dwelling dinoflagellate genera Adenoides and Pseudadenoides are morphologically very close but distinct in their molecular phylogeny. We established three cultures by isolating single cells from sand samples collected in intertidal zones of Qingdao (Yellow Sea), Dongshan (South China Sea) and Brittany (English Channel, North Atlantic, France). Strain morphology was examined with light and scanning electron microscopy, and both large subunit ribosomal DNA (LSU rDNA) and small subunit ribosomal DNA (SSU rDNA) sequences were amplified. Molecular phylogeny, corroborated by morphological examination showing the existence of a ventral pore, confirmed the identification of the French strain (RCC1982) as Adenoides eludens. The Chinese strains differed from Adenoides eludens in two additional posterior intercalary plates and differed from Pseudadenoides in one additional apical plate having the plate formula of Po, Cp, X, 5′, 6′′, 4S, 5′′′, 5p, 1′′′′ or alternatively Po, Cp, X, 5′, 6′′, 5S, 5′′′, 3p, 2′′′′. Maximum likelihood and Bayesian inference, carried out with concatenated LSU and SSU sequences, demonstrated that the Chinese strains were closely related but different from A. eludens and, in corroboration with morphological evidence, supported their classification as a distinct species, Adenoides sinensis sp. nov. Morphological and molecular results confirmed the close relationship between the two genera Adenoides and Pseudadenoides.

Diaporthosporellaceae, a novel family of Diaporthales (Sordariomycetes, Ascomycota)

Diaporthosporella cercidicola, collected from diseased branches of Cercis chinensis in China, is herein described and illustrated. Evidence for this new genus and species is provided by both holomorphic morphology and phylogenetic analysis. Diaporthosporella cannot be classified into any existing family. Thus, Diaporthosporellaceae is introduced as a new family to accommodate Diaporthosporella, typified by D. cercidicola. Morphologically, Diaporthosporellaceae can be distinguished from other diaporthalean families by irregularly uniseriate, allantoid or subreniform ascospores, conidiophores acropleurogenous, branched or sympodially branched, cylindrical, aseptate, and ellipsoidal, biguttulate conidia. Phylogenetic analysis using the internal transcribed spacers (ITS) and large subunit (LSU) ribosomal (r) DNA sequence data shows that Diaporthosporellaceae forms a distinct family within Diaporthales.

First record of resting cysts of the benthic dinoflagellate Prorocentrum leve in a natural reservoir in Gujan-Mestras, Gironde, France.

The resting cysts of the benthic dinoflagellate Prorocentrum leve from a natural reservoir in Gujan-Mestras (Gironde, France) were described in this study. The incubated urn-shaped cysts gave rise to cells of P.leve. Morphological observations through light microscopy and scanning electron microscopy, particularly of the periflagellar platelets, combined with large subunit ribosomal DNA sequences obtained through single-cell analysis confirm their affinity to the species P.leve. The cysts were characterized by a specific shape and the presence of an anterior plug. This is the first conclusive evidence for fossilizable resting stages within the Prorocentrales, one of the major orders within theDinophyceae. Palynological treatments show that the cysts and endospores withstand hydrochloric and hydrofluoric acids. Micro-Fourier transform infrared analysis on single specimens suggests that the composition of the endospore is cellulosic and the cyst wall a more robust, noncellulosic β-glucan. The spectra overall are similar to other published spectra of resting cysts from autotrophic, planktonic dinoflagellates.

Dematipyriforma aquilariagen. et sp. nov., a New Hyphomycetous Taxon fromAquilaria crassna

A hyphomycetous fungus producing dark muriform conidia, was isolated as endophyte from trunk of Aquilaria crassna in Laos. The fungus was compared to morphologically similar genera, such as Annellophorella, Berkleasmium, Canalisporium, and Monodictys. Morphological evidence, however, excluded the fungal taxon from any of these genera. Phylogenetic analysis of combined small subunit, 5.8S, and large subunit ribosomal DNA sequence data placed the fungus within the order Savoryellales (Sordariomycetes, Hypocreomycetidae), but on a distinct terminal clade along with other groups of the order. Based on morphological and molecular phylogenetic evidence, we therefore established the genus Dematipyriforma to accommodate the taxon, which was named Dematipyriforma aquilaria.

Cyst-motile stage relationship, morphology and phylogeny of a new chain-forming, marine dinoflagellate Grammatodinium tongyeonginum gen. & sp. nov. from Korea

:A new phototrophic dinoflagellate, Grammatodinium tongyeonginum gen. & sp. nov., was established by incubating resting cysts collected from surface sediment samples from Tongyeong coastal area, Korea. The resting cysts were ovoid with a large reddish pigment body and surrounded with a thick mucous layer that incorporated attached detritus particles. The vegetative cells were 24.6–40.9 μm long and 16.4–27.3 μm wide. The cell surface was covered with prominent longitudinal equidistant furrows. The cingulum was narrow and descended two to eight times its width. The nucleus was located at the central part of the epicone. The peripheral chloroplasts were usually granular and yellow-green in culture and were distributed along the rim of the cingulum. The horseshoe-shaped apical groove ran from the end of the sulcal extension anticlockwise around the apex. The distal end of the apical groove was located next to the extension of the sulcus and more to the ventral side than the proximal end. Molecular phylogenetic analysis using small subunit ribosomal DNA (SSU rDNA) gene sequences revealed that G. tongyeonginum was allied with the Cucumeridinium species. Large subunit ribosomal DNA (LSU rDNA) sequences revealed that G. tongyeonginum formed a clade distantly related to the other genera of Gymnodiniales. The combination of morphological characteristics with molecular phylogenies distinguished the present species from other genera within Gymnodiniales.

Cryptic diversity within the harmful dinoflagellate Akashiwo sanguinea in coastal Chinese waters is related to differentiated ecological niches

Blooms of the harmful dinoflagellate Akashiwo sanguinea are responsible for the mass mortality of fish and invertebrates in coastal waters. This cosmopolitan species includes several genetically differentiated clades. Four clonal cultures were established by isolating single cells from Xiamen Harbour (the East China Sea) for morphological and genetic analyses. The cultures displayed identical morphology but were genetically different, thus revealing presence of cryptic diversity in the study area. New details of the apical structure complex of Akashiwo sanguinea were also found. To investigate whether the observed cryptic diversity was related to environmental differentiation, 634 cells were obtained from seasonal water samples collected from 2008 to 2012. These cells were sequenced by single-cell PCR. For comparison with Chinese material, additional large subunit ribosomal DNA sequences were obtained for three established strains from Malaysian and French waters. To examine potential ecological differentiation of the distinct genotypes, growth responses of the studied strains were tested under laboratory conditions at temperatures of 12°C to 33°C. These experiments showed four distinct ribotypes of A. sanguinea globally, with the ribotypes A and B co-occuring in Xiamen Harbour. Ribotype A of A. sanguinea was present year-round in Xiamen Harbour, but it only bloomed in the winter and spring, thus corresponding to the winter type. In contrast, A. sanguinea ribotype B bloomed only in the summer, corresponding to the summer type. This differentiation supports the temperature optimum conditions that were established for these two ribotypes in the laboratory. Ribotype A grew better at lower temperatures compared to ribotype B which preferred higher temperatures. These findings support the idea that various ribotypes of A. sanguinea correspond to distinct ecotypes and allopatric speciation occurred in different climatic regions followed by dispersal.

Identification ofAzadinium poporum(Dinophyceae) in the Southeast Pacific: morphology, molecular phylogeny, and azaspiracid profile characterization

Azaspiracids (AZA), a group of lipophilic phycotoxins, are produced by some species of the marine dinophycean genus Azadinium. AZA have recently been detected in shellfish from the Southeast Pacific, however, AZA-producing species have not been recorded yet from the area. This study is the first record of the genus Azadinium and of the species Azadinium poporum from the Pacific side of South America. Three strains of A. poporum from Chanaral (Northern Chile) comply to the type description of A. poporum by the presence of multiple pyrenoids, in thecal plate details, and in the position of the ventral pore located on the left side of the pore plate. Molecular phylogeny, based on internal transcribed spacer and large subunit ribosomal DNA sequences, revealed that Chilean strains fall in the same ribotype clade as European and strains from New Zealand. Analyses of AZA profiles using LC–MS/MS showed an identical profile for all three strains with the presence of AZA-11 and two phosphorylated AZA. This is the first confirmation of the presence of AZA producing Azadinium in the Chilean coastal area and underlines the risk of AZA shellfish and concomitant human contamination episodes in the Southeast Pacific region.

Morphology and phylogeny of Triadinium polyedricum (Pouchet) Dodge (Dinophyceae) from Korean coastal waters

To identify features that can be used to differentiate Triadinium polyedricum from other related species, such as Fukuyoa paulensis and Alexandrium species, the detailed morphology and phylogeny of T. polyedricum collected from Korean coastal waters were investigated. The cells had a plate formula of Po, 3′, 7″, 5‴, 1p and 2″″, which is consistent with morphological descriptions in previous reports. Large subunit ribosomal DNA sequences also revealed that T. polyedricum from Korean coastal waters is identical to previously recorded isolates. T. polyedricum is morphologically characterized by a ventral pore in the 1″ plate that is comparable to F. paulensis and Alexandrium species. This result indicates that the location and presence of this ventral pore seems suitable for differentiating T. polyedricum from other related species.

Huia caspica gen. & comb. nov., a dinoflagellate species that recently crossed the marine‐freshwater boundary

SUMMARYThe dinoflagellate subfamily Diplopsalidoideae encompasses 11 genera whose plate patterns show a large diversity. In a recently published molecular phylogeny (Liu et al. 2015) some of these genera (e.g. Diplopsalis, Diplopelta) are polyphyletic, suggesting that further subdivision of these genera is needed. Here we established the cyst‐theca relationship of Diplopsalis caspica by incubating cysts collected from the East China Sea. Cells of D. caspica display a plate formula of Po, X, 3′, 1a, 6″, 3c+t, ?4s, 5″′, 1″″, characterized by a small, parallelogrammic anterior intercalary plate (1a) located in the middle of the dorsal part of the epitheca. The cysts are spherical and smooth‐walled with a theropylic archeopyle. In addition, we obtained four large subunit ribosomal DNA (LSU rDNA) sequences from the germinated motile cells by single‐cell polymerase chain reaction. Strains of D. caspica from the marine environment of the East China Sea differ at 0–2 positions of LSU rDNA sequences from that of lacustrine strains from NE China. In the molecular phylogeny, D. caspica was close to Lebouraia pusilla but distant from D. lenticula, the type species of Diplopsalis. Our results support the systematic importance of plate 1a, and therefore D. caspica was transferred to a new genus, Huia. The conservative LSU rDNA sequences in H. caspica suggest that the marine‐freshwater transition occurred recently.

Yeast diversity and novel yeast D1/D2 sequences from corn phylloplane obtained by a culture-independent approach.

Culture-independent techniques have recently been used for evaluation of microbial diversity in the environment since it addresses the problem of unculturable microorganisms. In this study, the diversity of epiphytic yeasts from corn (Zea mays Linn.) phylloplanes in Thailand was investigated using this technique and sequence-based analysis of the D1/D2 domains of the large subunit ribosomal DNA sequences. Thirty-seven samples of corn leaf were collected randomly from 10 provinces. The DNA was extracted from leaf washing samples and the D1/D2 domains were amplified. The PCR products were cloned and then screened by colony PCR. A total of 1049 clones were obtained from 37 clone libraries. From this total, 329 clones (213 sequences) were closely related to yeast strains in the GenBank database, and they were clustered into 77 operational taxonomic units (OTUs) with a similarity threshold of 99%. The majority of sequences (98.5%) were classified into the phylum Basidiomycota. Sixteen known yeast species were identified. Interestingly, more than 65% of the D1/D2 sequences obtained by this technique were suggested to be sequences from new yeast taxa. The predominant yeast sequences detected belonged to the order Ustilaginales with relative frequency of 68.0%. The most common known yeast species detected on the leaf samples were Pseudozyma hubeiensis pro tem. and Moesziomyces antarcticus with frequency of occurrence of 24.3 and 21.6%, respectively.

Phylloporia minutipora and P. radiata spp. nov. (Hymenochaetales, Basidiomycota) from China and a key to worldwide species of Phylloporia

Phylloporia is a monophyletic genus within the Hymenochaetaceae as recovered by nuclear large subunit ribosomal DNA (nLSU) sequences. According to the summarization of 38 species accepted in this genus, Phylloporia is characterized by an absence of setae and the presence of abundant thick-walled, colored and tiny basidiospores, although its other morphological characters are highly diverse. Nine herbarium specimens from China, fitting the morphological concept of Phylloporia, were morphologically and phylogenetically studied in detail. The phylogeny inferred from nLSU sequences shows that the nine specimens formed three terminal lineages within the Phylloporia clade. Two lineages being composed of four specimens from Hainan and three from Guizhou were newly described as Phylloporia minutipora and P. radiata, respectively. In Phylloporia, P. minutipora is distinct by a combination of annual, sessile and imbricate basidiocarps, distinctly concentrically sulcate pileal surface with obtuse margin, angular pores of 12–15 per mm, duplex context separated by a black zone, a dimitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3 × 2–2.5 μm, while P. radiata is distinct by a combination of annual, sessile and imbricate basidiocarps, faintly sulcate and radially striate pileal surface, sharp pileal margin, angular pores of 8–10 per mm, duplex context separated by a black zone, a monomitic hyphal system, and broadly ellipsoid basidiospores of 2.5–3.5 × 2–2.5 μm. The third lineage, comprising two specimens from Hainan, was morphologically determined as Phylloporia pulla. This species was recently combined to Phylloporia based on only morphological characters, and the current study for the first time generated its molecular sequences for phylogenetic reference. A key to all 40 species of Phylloporia is provided.

Cyst-theca relationship and phylogenetic positions of Scrippsiella plana sp. nov. and S. spinifera (Peridiniales, Dinophyceae)

Species belonging to the dinophyte genus Scrippsiella are frequently reported in marine waters, but information on their distribution in brackish environments is limited. Here we describe a new species, S. plana, through incubation of non-calcified cysts from sediments collected in the South China Sea and Caspian Sea. The vegetative cells consist of a conical epitheca and a rounded hypotheca with the plate formula of Po, X, 4′, 3a, 7′′, 5C+t, 5S, 5′′′, 2′′′′. It differs from other Scrippsiella species by its flattened body in dorsoventral view and a small first anterior intercalary (1a) plate (half the size of plate 3a). Scrippsiella plana strains from the South China Sea and Caspian Sea share identical internal transcribed spacer (ITS) sequences, and show phenotypic plasticity and local adaptation in growth rate at various salinities, consistent with the environments in which they originated. In addition, two strains of S. spinifera were obtained by incubating ellipsoid cysts with calcareous spines from sediments collected along the Turkish and Hawaiian coast. They also share identical ITS sequences and differ from Duboscquodinium collinii (a parasite of tintinnids) only at two base pair positions (in the ITS2 region). Molecular phylogeny based on ITS and large subunit ribosomal DNA (LSU rDNA) sequences revealed that S. plana was nested within the Calciodinellum (CAL) clade and S. spinifera within the S. trochoidea (STR) clade. The phylogenetic position of ‘Peridinium’ wisconsinense is reported for the first time, which supports multiple transitions of the Peridiniales to freshwater.