Otospora bareai, a new fungal species in the Glomeromycetes from a dolomitic shrub land in Sierra de Baza National Park (Granada, Spain)

A new fungal species of the Glomeromycetes was isolated from the rhizosphere of Pterocephalus spathulatus and Thymus granatensis, two rare endemic plants growing on dolomite in the Sierra de Baza (Granada, southern Spain). The fungus was propagated in pot cultures of Sorghum vulgare and Trifolium pratense for 4 y and it is described here on the basis of the spores found in nature and formed in pot cultures. Its brown spores (140-210 microm diam) form laterally on a persistent, brown stalk (=neck) of a sporiferous saccule. They have two walls without ornamentation: a brown, three- to four-layered outer wall and a hyaline two- to three-layered inner wall. The unique combination of spore formation and spore wall structure does not fit with any of the known fungal genera. Spore formation is similar to that of Acaulospora spp. and Archaeospora trappei, but Acaulospora spp. has three spore walls with a characteristic "beaded" wall, and the outer wall of Ar. trappei is simple, thin, hyaline and only bilayered. Spore wall structure of the new fungus is similar to that of Entrophospora infrequens, however this fungus forms its spores internally, inside the hyphal stalk of the sporiferous saccule. Molecular analyses of the small subunit of the ribosomal gene phylogenetically place the new fungus next to Diversispora spurca, which forms one-walled glomoid spores (i.e. terminally on hyphae). Based on these analyses we place the new fungus into a new genus in the family Diversisporaceae under the epithet Otospora bareai.     

Development of Acaulospora rehmii spore and hyphal swellings under root-organ culture

A strain of Acaulospora rehmii was, for the first time, successfully grown in vitro on Ri T-DNA transformed carrot roots allowing the in situ observation of Acaulospora spore development and of extraradical thin-walled hyphal swellings. The sporogenous hypha developed intercalarly along thin-walled coenocytic hyphae. The distal part of the sporogenous hypha swelled slightly as a sporiferous saccule primordium followed by the differentiation of a lateral spore primordium along the neck of the sporogenous hypha. Both structures matured simultaneously, and the sporiferous saccule began to collapse after spore maturation and complete differentiation of the spore wall. Several of the in situ observations on in vitro differentiated A. rehmii spores are concordant with previous ontogenic studies done on other Acaulospora species obtained from in vivo cultures. New and original observations on the early developmental stages of sporiferous saccules and spores and on the occurrence of small diameter intercalary hyphal swellings provide additional elements in the study of Acaulospora sporulation process and life cycle.     

Acaulospora alpina, a new arbuscular mycorrhizal fungal species characteristic for high mountainous and alpine regions of the Swiss Alps

Acaulospora alpina sp. nov. forms small (65-85 microm diam), dark yellow to orange-brown spores laterally on the neck of hyaline to subhyaline sporiferous saccules. The spores have a three-layered outer spore wall, a bi-layered middle wall and a three-layered inner wall. The surface of the second layer of the outer spore wall is ornamented, having regular, circular pits (1.5-2 microm diam) that are as deep as wide and truncated conical. A "beaded" wall layer as found in most other Acaulospora spp. is lacking. The spore morphology of A. alpina resembles that of A. paulinae but can be differentiated easily by the unique ornamentation with the characteristic pits and by the spore color. A key is presented summarizing the morphological differences among Acaulospora species with an ornamented outer spore wall. Partial DNA sequences of the ITS1, 5.8S subunit and ITS2 regions of ribosomal DNA show that A. alpina and A. paulinae are not closely related. Acaulospora lacunosa, which has similar color but has generally bigger spores, also has distinct rDNA sequences. Acaulospora alpina is a characteristic member of the arbuscular mycorrhizal fungal communities in soils with pH 3.5-6.5 in grasslands of the Swiss Alps at altitudes between 1800 and 2700 m above sea level. It is less frequent at 1300-1800 m above sea level, and it so far has not been found in the Alps below 1300 m or in the lowlands of Switzerland.     

Dimorphic spore production in the genus Acaulospora

Species of the genus Acaulospora are partly characterized by the production of ‘acaulosporoid’ spores. The simultaneous formation of glomoid and acaulosporoid spores by some species in the Glomeromycota has been used as a basis for taxonomic classification. We report the presence of both glomoid and acaulosporoid spores in four Acaulospora species. Analysis of the 18S rRNA gene confirmed that only A. spinosa was present in a pot culture that produced two morphs. The functional significance of dimorphic spore production is unknown but the production of blastic spores is not a characteristic that can have any significance as a taxonomic character.     

碎米蕨属的系统学研究——基于4种叶绿体DNA序列片段

碎米蕨属(Cheilosoria Trevis.)隶属碎米蕨类, 由于形态上的趋同进化, 使得该类群的系统分类一直存在争议。该研究对该碎米蕨属植物的4种叶绿体DNA序列片段(rbcL/matK/rps4/rps4-trnS)进行PCR扩增和序列分析, 再结合其它相关类群, 用贝叶斯法和最大似然法构建系统树并探讨其系统发育关系。结果表明, 碎米蕨属不是一个单系类群, 旧世界分布的碎米蕨属植物(薄叶碎米蕨除外)均聚在亚洲Cheilanthes群内, 与粉背蕨属(Aleuritopteris Fée)等类群形成不同亚支。该属孢子形态具有明显异质性。薄叶碎米蕨(Cheilosoria tenuifolia (Burm. f.) Trevis.)与亚洲其它碎米蕨属植物的系统位置相距甚远, 且与隐囊蕨(Notholaena hirsuta (Poir.) Desv.)聚为完全支持的分支, 两者可能均为大洋洲起源, 并属于另一类群。美洲和旧世界分布的碎米蕨属植物关系较远, 二者可能代表了不同的演化路线。     

Acaulospora brasiliensis comb. nov. and Acaulospora alpina (Glomeromycota) from upland Scotland: morphology, molecular phylogeny and DNA-based detection in roots

Spores of two supposedly arbuscular mycorrhizal fungal species, new to the United Kingdom and recently described as Acaulospora alpina and Ambispora brasiliensis (Glomeromycota), were discovered in soil samples from moorland in upland Scotland. Soil and plant trap pot cultures were established, but attempts to establish these fungi in single-species pot cultures with Plantago lanceolata as host were unsuccessful. Nevertheless, based on a 1.5-kb DNA fragment spanning part of the small subunit rRNA gene, the internal transcribed spacer region and part of the large subunit rRNA gene, both these species could be detected directly in field-sampled roots, together with one uncultured species each of Scutellospora, Rhizophagus (former Glomus group Ab, or ‘Glomus intraradices clade’) and Acaulospora. Whereas A. alpina has characteristic morphological similarities to other species in its genus, A. brasiliensis morphologically has little in common with any other species in Ambispora. The molecular phylogeny, DNA barcoding and morphological evidence clearly place A. brasiliensis in the genus Acaulospora. We therefore rename the species, reported from Brazil and Scotland, as Acaulospora brasiliensis comb. nov., and discuss ecological aspects of the very different environments from which A. brasiliensis and A. alpina have been reported.     

Two new lineages of aquatic ascomycetes: <Emphasis Type="Italic">Atractospora</Emphasis> gen. nov. and <Emphasis Type="Italic">Rubellisphaeria</Emphasis> gen. et sp. nov., and a sexual morph of <Emphasis Type="Italic">Myrmecridium montsegurinum</Emphasis> sp. nov.

Two new genera, Atractospora and Rubellisphaeria, are described for perithecial ascomycetes occurring on decaying wood submerged in freshwater habitats. Their relationships with other morphologically similar fungi were investigated utilising four nuclear ribosomal and protein-coding loci. They are nested together with members of five orders and families and numerous genera incertae sedis in the Sordariomycetidae in a clade supported by Maximum Likelihood and Bayesian inference methods. Their closest relative is Lentomitella. Atractospora includes species characterised by dark, immersed to semi-immersed beaked ascomata lying horizontally to the host, stipitate asci with a pronounced non-amyloid apical annulus and hyaline, fusiform, septate, thick-walled ascospores with smooth or ornamented wall. Three novel species are introduced (A. decumbens, A. reticulata and A. verruculosa). A new combination for Aquaticola ellipsoidea is proposed in Atractospora based on molecular data and morphological characters. Rubellisphaeria, with a new species R. abscondita, is distinct by subhyaline to reddish brown, immersed ascomata with a lateral neck, short-stipitate asci and ellipsoidal smooth ascospores with a delayed formation of a middle septum. The sexual morph of the dematiaceous hyphomycete genus Myrmecridium was encountered for the first time on decaying wood submerged in a stream. It is nested in a strongly supported monophyletic clade of the Myrmecridiales. The novel species M. montsegurinum is described; it possesses papillate ascomata immersed beneath a clypeus with subhyaline to weakly pigmented ascomatal wall, long-stipitate asci with a non-amyloid apical annulus and three-septate, hyaline, ellipsoidal, delicately verruculose ascospores. A morphology-based key is provided to facilitate identification of species of Atractospora.     

Glomus, the largest genus of the arbuscular mycorrhizal fungi (Glomales), is nonmonophyletic.

Arbuscular mycorrhizal (AM) fungi form a widespread and ecologically important symbiosis with plants in the land ecosystem. The phylogeny of the largest presently accepted genus, Glomus, of the monogeneric family Glomaceae (Glomales; AM fungi) was analyzed. Phylogenetic trees were computed from nearly full-length SSU rRNA gene sequences of 30 isolates, and show that "Glomus" is not monophyletic. Even after the very recent separation of Archaeospora and Paraglomus from "Glomus," the genus further separates into two suprageneric clades. One of them diverges further into two subclades, differing by phylogenetic distances equivalent to family level. The other, comprising Glomus versiforme, G. spurcum, and a species morphologically similar to G. etunicatum, is not closely related to the Glomaceae, but clusters together with the Acaulosporaceae and Gigasporaceae in a monophyletic clade. Based on the molecular evidence, a new family, separate from the Glomaceae, is required to accommodate this group of organisms, initially named Diversisporaceae fam. ined. The current taxonomic concept of the recently erected family Archaeosporaceae also requires future emendation, because Geosiphon pyriformis (Geosiphonaceae) renders Archaeospora, the sole genus formally included in this family, paraphyletic. The suborders Gigasporineae and Glominaeae are not congruent with the natural phylogeny of the AM fungi. Our data necessitate a general reexamination of the generic concepts within the Glomales. In addition to the new family structure hypothesized herein, establishment of at least three new genera will be necessary in the future.     

Molecular phylogeny reveals a core clade of Rhytismatales

Rhytismatales (Leotiomycetes, Pezizomycotina, Ascomycota) are an order of mostly plant-associated ascomycetes with a global distribution. Well known taxa include the Rhytisma tar spots on Acer spp. and several needle-cast pathogens in genera Lophodermium and Meloderma. Critical studies are lacking at all taxonomic ranks from order to species, and in particular the genus taxonomy in the order has been criticized for being unnatural. We used nuclear LSU and mitochondrial SSU sequences in Bayesian phylogenetic analyses to define a core clade of Rhytismatales sensu stricto. Some of the genera traditionally placed within the Rhytismatales, Ascodichaena, Marthamyces, Mellitiosporium, Potebniamyces, Propolis and Pseudophacidium, are shown to be phylogenetically distinct, all related to various other taxa at present placed in the polyphyletic Helotiales. Within the core clade only Cudonia, Spathularia and Terriera are supported as monophyletic. The large genera Coccomyces, Hypoderma and Lophodermium all are polyphyletic as are a few smaller genera. The traditionally used characters of ascoma and spore shape are shown to be unreliable for the delimitation of monophyletic genera but in some cases can be useful when combined with other characters. In this study we provide 72 new nrLSU and 64 new mtSSU sequences. Together with publicly available sequences data for 103 specimens representing 91 species of Rhytismatales are now available. Despite this taxon sampling intensity is still too low to propose an alternative generic taxonomy.     

Ambispora granatensis, a new arbuscular mycorrhizal fungus, associated with Asparagus officinalis in Andalucia (Spain)

A new dimorphic fungal species in the arbuscular mycorrhiza-forming Glomeromycota, Ambispora granatensis, was isolated from an agricultural site in the province of Granada (Andalucía, Spain) growing in the rhizosphere of Asparagus officinalis. It was propagated in pot cultures with Trifolium pratense and Sorghum vulgare. The fungus also colonized Ri T-DNA transformed Daucus carota roots but did not form spores in these root organ cultures. The spores of the acaulosporoid morph are 90-150 μm diam and hyaline to white to pale yellow. They have three walls and a papillae-like rough irregular surface on the outer surface of the outer wall. The irregular surface might become difficult to detect within a few hours in lactic acid-based mountings but are clearly visible in water. The structural central wall layer of the outer wall is only 0.8-1.5 μm thick. The glomoid spores are formed singly or in small, loose spore clusters of 2-10 spores. They are hyaline to pale yellow, (25)40-70 μm diam and have a bilayered spore wall without ornamentation. Nearly full length sequences of the 18S and the ITS regions of the ribosomal gene place the new fungus in a separate clade next to Ambispora fennica and Ambispora gerdemannii. The acaulosporoid spores of the new fungus can be distinguished easily from all other spores in genus Ambispora by the conspicuous thin outer wall.     

Phylogenetic relationships of the bulbuls (Aves: Pycnonotidae) based on mitochondrial and nuclear DNA sequence data

Bulbuls (Aves: Pycnonotidae) are a fairly speciose (ca. 130 sp.) bird family restricted to the Old World. Family limits and taxonomy have been revised substantially over the past decade, but a comprehensive molecular phylogeny for the family has not been undertaken. Using nuclear and mitochondrial DNA sequences, we reconstructed a well-supported phylogenetic hypothesis for the bulbuls. Three basal lineages were identified: a large African clade, a large Asian clade that also included African Pycnonotus species, and the monotypic African genus Calyptocichla. The African clade was sister to the other two lineages, but this placement did not have high branch support. The genus Pycnonotus was not monophyletic because three species (eutilotus, melanoleucos, and atriceps) were highly diverged from the other species and sister to all other Asian taxa. Additional taxon sampling is needed to further resolve relationships and taxonomy within the large and variable Hypsipetes complex.     

THE PHYLOGENY OF CAULERPA BASED ON RDNA INTERNAL TRANSCRIBED SPACER SEQUENCES

Phylogenetic hypotheses for the pantropical marine green algal genus, Caulerpa , were inferred based on analyses of nuclear-encoded rDNA internal transcribed spacer (ITS) sequences. Results of these analyses were used to assess the correspondence between rDNA phylogeny and traditional sectional taxonomy, to identify synapomorphic morphological characters (including assimilator morphology and chloroplast ultrastructure), and to examine marine biogeographic hypotheses for the genus. Ribosomal DNA ITS sequences were aligned for thirty-three species and intraspecific taxa of Caulerpa. Results indicate limited correspondence between phylogeny and sectional taxonomy for the genus, (e.g., the sections Filicoideae and Sedoideae were not monophyletic). In contrast, chloroplast morphology could be mapped to the tree topology with limited homoplasy. Pantropical isolates of the filicoidean species, Caulerpa sertularioides and Caulerpa mexicana each formed monophyletic groups. Caulerpa reyesii was included as a derived taxon within the Caulerpa taxifolia clade, suggesting that these species were conspecific and affirmed the lack of correspondence between phylogeny and assimilator morphology. Isolates and various intraspecific taxa of Caulerpa racemosa did not form a monophyletic group. Instead, these taxa formed a heterogeneous assemblage with other sedoidean and filicoidean taxa. Within the C. sertularioides clade, Caribbean and Atlantic isolates formed a basal paraphyletic group, whereas eastern and western Pacific isolates formed a more derived monophyletic group. Therefore, these results are not consistent with an Indo-West Pacific origin of this species.     

Phylogeny and evolution of Perezia （Asteraceae： Mutisieae： Nassauviinae）

A molecular phylogenetic analysis of most of the species of Perezia reveals that, as traditionally defined, the genus is not monophyletic with two species more closely related to Nassauvia than to Perezia. In addition, our results show that Burkartia （Perezia） lanigera is related to Acourtia and is the only member of that clade in South America. The remaining species are monophyletic and show a pattern of an early split between a western temperate and an eastern subtropical clade of species. Within the western clade, the phylogeny indicates a pattern of diversification that proceeded from southern, comparatively low-elevation habitats to southern high-elevation habitats, and ultimately into more northern high-elevation habitats. The most derived clades are found in the high central Andes, where significant radiation has occurred.     

Isolation of the symbiotic fungus of Acromyrmex pubescens and phylogeny of Leucoagaricus gongylophorus from leaf-cutting ants

Leaf-cutting ants live in an obligate symbiosis with a Leucoagaricus species, a basidiomycete that serves as a food source to the larvae and queen. The aim of this work was to isolate, identify and complete the phylogenetic study of Leucoagaricus gongylophorus species of Acromyrmex pubescens. Macroscopic and microscopic features were used to identify the fungal symbiont of the ants. The ITS1-5.8S-ITS2 region was used as molecular marker for the molecular identification and to evaluate the phylogeny within the Leucoagaricus genus. One fungal symbiont associated with A. pubescens was isolated and identified as L. gongylophorus. The phylogeny of Leucoagaricus obtained using the ITS molecular marker revealed three well established monophyletic groups. It was possible to recognize one clade of Leucoagaricus associated with phylogenetically derived leaf-cutting ants (Acromyrmex and Atta). A second clade of free living forms of Leucoagaricus (non-cultivated), and a third clade of Leucoagaricus associated with phylogenetically basal genera of ants were also recognized. The clades corresponded to traditional taxonomic groups, and were differentiated by ecological habitats of different species.     

Phylogenetic relationships of the New World Troidini swallowtails (Lepidoptera: Papilionidae) based on COI, COII, and EF-1alpha genes

A phylogeny of the Neotropical members of the Tribe Troidini (Lepidoptera: Papilionidae) was obtained with sequences of three protein-coding genes: two mitochondrial (COI and COII), and one nuclear (EF-1alpha). Parsimony and Bayesian analyses of 33 taxa resulted in very similar trees regardless of method used with the 27 troidines always forming a monophyletic clade. Within Troidini, the genus Battus is sister group to the remaining troidines, followed by a clade formed by the Paleotropical taxa (here represented by three exemplars). The genus Euryades is the next branch, and sister group of Parides. The genus Parides is monophyletic, and is divided into four main groups by Maximum Parsimony analysis, with the most basal group composed of tailed species restricted to SE Brazil. Character optimization of ecological and morphological traits over the phylogeny proposed for troidines indicated that the use of several species of Aristolochia is ancestral over the use of few or a single host-plant. For the other three characters, the ancestral states were the absence of long tails, forest as the primary habitat and oviposition solitary or in loose group of several eggs.     

Exploring the evolution of humus collecting leaves in drynarioid ferns (Polypodiaceae, Polypodiidae) based on phylogenetic evidence

Most species of the paleotropic fern genera Aglaomorpha and Drynaria, together constituting a monophyletic clade (drynarioid ferns), possess humus-collecting structures as an adaptation to their epiphytic life form. Humus-collectors are either present as a specialized foliar structure (external leaf dimorphism) or as a specialized leaf part (internal dimorphism). Apart from these basic patterns there are several forms of reduction and an internal fertile – sterile dimorphism in Aglaomorpha. We present a phylogeny of drynarioid ferns based on morphological and molecular (cpDNA) markers. The genus Aglaomorpha was found to be monophyletic, whereas Drynaria is likely to be a paraphyletic assemblage including a grade of Himalayan to Southern Chinese taxa basal to Aglaomorpha. The evolution of humus-collectors is reconstructed by plotting their character state changes onto the obtained phylogeny. Despite the complex morphological pattern across species, evolution of drynarioid humus-collecting structures can be reconstructed postulating a simple sequence of character state changes based on only a few elementary processes.     

Phylogenetic analysis of the grape family (Vitaceae) based on three chloroplast markers

Seventy-nine species representing 12 genera of Vitaceae were sequenced for the trnL-F spacer, 37 of which were subsequently sequenced for the atpB-rbcL spacer and the rps16 intron. Phylogenetic analysis of the combined data provided a fairly robust phylogeny for Vitaceae. Cayratia, Tetrastigma, and Cyphostemma form a clade. Cyphostemma and Tetrastigma are each monophyletic, and Cayratia may be paraphyletic. Ampelopsis is paraphyletic with the African Rhoicissus and the South American Cissus striata nested within it. The pinnately leaved Ampelopsis form a subclade, and the simple and palmately leaved Ameplopsis constitutes another with both subclades containing Asian and American species. Species of Cissus from Asia and Central America are monophyletic, but the South American C. striata does not group with other Cissus species. The Asian endemic Nothocissus and Pterisanthes form a clade with Asian Ampelocissus, and A. javalensis from Central America is sister to this clade. Vitis is monophyletic and forms a larger clade with Ampelocissus, Pterisanthes, and Nothocissus. The eastern Asian and North American disjunct Parthenocissus forms a clade with Yua austro-orientalis, a species of a small newly recognized genus from China to eastern Himalaya. Vitaceae show complex multiple intercontinental relationships within the northern hemisphere and between northern and southern hemispheres.     

Preliminary phylogenetic analysis of the fern genus Lomariopsis (Lomariopsidaceae)

A preliminary phylogenetic analysis is presented forLomariopsis based on sequence data from the chloroplast intergenic spacertrnL-trnF. The analysis includes 27 (60%) of the approximately 45 species in the genus. A strict consensus of six most parsimonious trees supports two main clades—theSorbifolia-group and theJapurensis-group—previously proposed based on heteroblastic leaf development. TheSorbifolia-group is entirely neotropical and includes all the Antillean species. The species in this clade had either smooth or crested spores, but the tree was ambiguous whether these spore types define two separate clades. TheJapurensis-group consists of two clades, one primarily neotropical and the other entirely paleotropical. Within the neotropical clade nests a clade of two African species, which have long-spiny spores typical of the neotropical clade and unlike those found in the African-Madagascan clade. The occurrence of these two species in Africa is best explained by longdistance spore dispersal of their ancestral species from the neotropics to Africa. Within the paleotropical clade of theJapurensis-group, a clade of three African species is nested among seven species from Madagascar (all the species from that island). Within the genus as a whole, a derived character—the abortion of the rachis apex and its replacement by the distal lateral pinna assuming a terminal position—was found to have evolved separately in each of the four species with this kind of leaf apex. A scanning electron microcope study of the spores revealed five types, and a transformation series for these different types is proposed. Characters of spore morphology and heteroblastic leaf development agreed with many of the clades in the phylogenetic tree. This study represents the first phylogeny for the genus.     

Molecular systematics of a speciose, cosmopolitan songbird genus: defining the limits of, and relationships among, the Turdus thrushes

The avian genus Turdus is one of the most speciose and widespread of passerine genera. We investigated phylogenetic relationships within this genus using mitochondrial DNA sequence data from the ND3, ND2 and cytochrome b genes. Our sampling of Turdus included 60 of the 65 extant species currently recognized, as well as all four species from three genera previously shown to fall inside Turdus (Platycichla, Nesocichla, and Cichlherminia). Phylogenetic trees based on maximum likelihood and maximum parsimony algorithms were congruent. Most of the Turdus taxa sampled fall into one of four clades: an African clade, a Central American-Caribbean clade, a largely South American clade, and a Eurasian clade. Still other taxa are placed either at the base of Turdus, or as links between clades. In no instance is any continent reciprocally monophyletic for the species distributed on it. A general lack of nodal support near the base of the phylogeny seems related to a rapid intercontinental establishment of the major clades within Turdus very early in the history of the genus. The monotypic genus Psophocichla is distantly related to, but clearly the sister of, Turdus rather than a constituent member of it.