Three new genera representing novel lineages of Sordariomycetidae (Sordariomycetes, Ascomycota) from tropical freshwater habitats in Costa Rica

Three new genera are established in the Sordariomycetidae based on morphological and molecular data (SSU and LSU nrDNA) to accommodate five ascomycete species collected from submerged woody debris in freshwater habitats from Costa Rica. The genus Bullimyces contains three new species, B. communis, B. costaricensis and B. aurisporus. Bullimyces is characterized by globose to subglobose, membranous, black, ostiolate ascomata; deliquescent, hyaline, globose cells that fill the center of the centrum; unitunicate asci that deliquesce early in some species; and septate, thick-walled ascospores with or without gelatinous sheaths or appendages. Bullimyces species form a well supported clade with 100% bootstrap support, but the position of the genus in the Sordariomycetidae remains unclear. The second genus, Riomyces, is represented by a single species, R. rotundus. Riomyces is characterized by globose to subglobose, membranous, black, ostiolate ascomata, unitunicate, cylindrical asci, hyaline, globose cells that fill the hamathecium and septate, thick-walled ascospores with a gelatinous sheath. Although Riomyces is morphologically similar to Bullimyces, the two genera did not group together with support in any analysis. The third genus, Hydromelitis, is represented by a single species, H. pulchella. Hydromelitis is characterized by pyriform, membranous, black, ostiolate ascomata, unitunicate asci lacking an apical structure, simple, thin-walled, septate paraphyses and hyaline to golden yellow, multiseptate, thick-walled ascospores with a gelatinous sheath. Bullimyces, Riomyces and Hydromelitis were nested within an unsupported clade consisting of members of the Ophiostomatales, Magnaporthales and freshwater Annulatacaceae sensu lato and sensu stricto.     

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.     

Hybridization and polyploidy of an aquatic plant, Ruppia (Ruppiaceae), inferred from plastid and nuclear DNA phylogenies

? Premise of the study: The monogeneric family Ruppiaceae is found primarily in brackish water and is widely distributed on all continents, many islands, and from subartic to tropical zones. Ruppia taxonomy has been confusing because of its simplified morphology yet high phenotypic plasticity and the existence of polyploidy and putative hybrids. This study addresses the current classification of species in the genus, the origin of putative hybrids and polyploids, and the distribution of Ruppia species. ? Methods: Separate molecular phylogenetic analyses using plastid DNA and nuclear-encoded PHYB data sets were performed after chromosome observations. ? Key results: The resultant trees were largely congruent between genomes, but were incongruent in two respects: the first incongruence may be caused by long outgroup branches and their effect on ingroup rooting, and the second is caused by the existence of heterogeneous PHYB sequences for several accessions that may reflect several independent hybridization events. Several morphological species recognized in previous taxonomic revisions appear paraphyletic in plastid DNA and PHYB trees. ? Conclusions: Given the molecular phylogenies, and considering chromosome number and morphology, three species and one species complex comprising six lineages were discerned. A putative allotriploid, an allotetraploid, and a lineage of hybrid origin were identified within the species complex, and a hybrid was found outside the species complex, and their respective putative parental taxa were inferred. With respect to biogeography, a remarkably discontinuous distribution was identified in two cases, for which bird-mediated seed dispersal may be a reasonable explanation.     

用nrDNA ITS序列探讨狭蕊龙胆属及其近缘属 (龙胆科)的系统发育

运用核糖体DNA内转录间隔区ITS序列对狭蕊龙胆属Metagentiana10种及其近缘属22种植物进行了系统发育分析。ITS分析结果表明狭蕊龙胆属是一个多系群:在系统发育树上,双蝴蝶属Tripterospermum和蔓龙胆属Crawfurdia的种类位于狭蕊龙胆属各分支中,而且双蝴蝶属和蔓龙胆属的种类也相互交叉;这一结果不支持将3个属各自独立为属。但是,在所有分析中,3个属共同形成一单系分支,是龙胆属Gentiana的姊妹群;这一结果与形态学、花部解剖学、细胞学、孢粉学和胚胎学等证据基本一致,狭蕊龙胆属应该从龙胆属中分离出来,它与双蝴蝶属和蔓龙胆属有更为密切的亲缘关系。根据分支图,在狭蕊龙胆属、双蝴蝶属和蔓龙胆属组成的复合群中,现已知的染色体基数x＝17、21和23可能存在网状和平行进化。     

Evolutionary relationships among species of Puccinia and Uromyces (Pucciniaceae,Uredinales) inferred from partial protein coding gene phylogenies

The two rust genera with the largest number of species are Puccinia Pers. ex Pers. and Uromyces (Link) Unger in the family Pucciniaceae (Uredinales). The hosts of these pathogens include representatives from almost all major angiosperm orders. Despite their ecological and economic importance, the status of Puccinia and Uromyces as distinct genera has been disputed, and little is known about relationships within and among these groups. Here we present phylogenetic analyses based on sequence data from the translation elongation factor 1α gene for over 60 species in the family Pucciniaceae. In particular, we investigate evolutionary relationships between Puccinia and Uromyces. A relatively smaller phylogeny using the beta-tubulin 1 gene was generated to test support for this phylogeny. Two main phylogenetic clades were identified and indicate at least two radiations within the Pucciniaceae. As expected neither Puccinia s. lat. nor Uromyces s. lat. are supported as monophyletic groups by either of the protein coding genes. However, both Puccinia sensu stricto (type P. graminis), and Uromyces sensu stricto (type U. appendiculatus) constitute distinct clades. In general, members of Uromyces spp. occurred scattered throughout the phylogeny suggesting that they represent more recent radiations. Several host families are found in both of the two main clades while two families, Poaceae and Cyperaceae, are separated, with one in each of the two main clades.     

丛赤壳科部分属之间的系统学关系

对nrDNA大亚基部分序列进行序列分析,探讨丛赤壳科11个属的属间关系。研究结果表明,Cosmospora不是单起源,它的成员分别与Nectria,Haematonectria以及Neocosmospora3个不同的属聚类在一起;Haematonectria和Neocosmospora的亲缘关系最接近;Lanatonectria为一个独立的属;以Neonectriadiscophoravar.discophora为代表的Neonectria是一个可靠的属。     

Phylogenetic relationships among genera of Massonieae (Hyacinthaceae) inferred from plastid DNA and seed morphology

The tribe Massonieae Baker (Hyacinthaceae-Hyacinthoideae) presently consists of about 19 genera and 230 species distributed from Africa (south of the Sahara) to Madagascar and India. Based on atpB and trnL-F DNA sequences the tribe is monophyletic only when the genus Pseudoprospero is excluded from Massonieae. In most trnL-F trees, this genus occupies a basal position within subfamily Hyacinthoideae and is sister to the rest of the subfamily. Molecular data suggest that the remaining genera of Massonieae do not share common ancestry with the Eurasian/North-African tribe Hyacintheae Dumort. (Scilla, Hyacinthus and allies), and thus a narrow concept of the essentially Eurasian genus Scilla is supported. Members of well-supported clades in Massonieae usually show similarities in seed characteristics as determined by scanning electron microscopy. Phylogenetic position and seed morphology indicate that Massonia angustifolia and M. zeyheri do not belong to the genus Massonia but fall into a clade together with Daubenya, Androsiphon and Amphisiphon. The genus Whiteheadia appears paraphyletic in the 50% majority rule trnL-F tree and occupies a basal position next to Massonia. However, in the strict consensus tree neither monophyly nor polyphyly can be excluded for this genus. Seed appendages are documented for members of the genera Ledebouria and Lachenalia. Within the genera of Massonieae there is a tendency towards bending of the seed axis. This phenomenon is most obvious within the genus Lachenalia. Delimitation of genera based on seed morphology largely agrees with the results of molecular studies. Correlation between number, size and color of seeds, geographical distribution and phylogenetic position of the genera are discussed. Electronic Publication     

Genetic diversity and phylogeny in Hystrix (Poaceae, Triticeae) and related genera inferred from Giemsa C-banded karyotypes

The phylogenetic relationships of 15 taxa from Hystrix and the related genera Leymus (NsXm), Elymus (StH), Pseudoroegneria (St), Hordeum (H), Psathyrostachys (Ns), and Thinopyrum (E) were examined by using the Giemsa C-banded karyotype. The Hy. patula C-banding pattern was similar to those of Elymus species, whereas C-banding patterns of the other Hystrix species were similar to those of Leymus species. The results suggest high genetic diversity within Hystrix, and support treating Hy. patula as E. hystrix L., and transferring Hy. coreana, Hy. duthiei ssp. duthiei and Hy. duthiei ssp. longearistata to the genus Leymus. On comparing C-banding patterns of Elymus species with their diploid ancestors (Pseudoroegneria and Hordeum), there are indications that certain chromosomal re-arrangements had previously occurred in the St and H genomes. Furthermore, a comparison of the C-banding patterns of the Hystrix and Leymus species with the potential diploid progenitors (Psathyrostachys and Thinopyrum) suggests that Hy. coreana and some Leymus species are closely related to the Ns genome of Psathyrostachys, whereas Hy. duthiei ssp. duthiei, Hy. duthiei ssp. longearistata and some of the Leymus species have a close relationship with the E genome. The results suggest a multiple origin of the polyploid genera Hystrix and Leymus.     

The early evolution of the mega‐diverse genus Begonia (Begoniaceae) inferred from organelle DNA phylogenies

Begonia L. is one of the largest flowering plant genera, a ubiquitous component of many tropical forests and an economically important ornamental plant. In the present study, we address the early evolution of Begonia by generating molecular phylogenies from approximately 7000 bases of chloroplast DNA and approximately 6000 bases of mitochondrial DNA for each of 30 exemplar Begonia species. Broadscale biogeographic patterns found in the phylogenies, together with previously estimated divergence dates, indicated that extant Begonia lineages first diversified in Africa and then subsequently in America and Asia. The phylogenies also revealed that the closest African relatives of the American and Asian Begonia are seasonally‐adapted species. Moderate to strong incongruence between the phylogenies suggested that they differ genealogically. These differences could have been the result of either interspecific hybridization and/or incomplete lineage sorting. The results obtained in the present study provide a much needed genus‐wide framework for future evolutionary studies of this exceptionally diverse tropical genus. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 243–250.     

Two new genera and species of the termite symbiont lineage Termitohospitini (Coleoptera,Staphylinidae, Aleocharinae) from Bolivia and peninsular Malaysia

Coptotermocola clavicornis gen. & sp. n. and Neotermitosocius bolivianus gen. & sp. n. of the termite inquilinous tribe Termitohospitini are described from peninsular Malaysia and Bolivia, respectively. The Termitohospitini are most readily diagnosable by the distally migrated anterior tentorial pits that are no longer associated with the antennal fossae, and by the enlarged vertex which obscures the antennal fossae dorsally. Additionally, the Termitohospitini are hypothesized to share a recent common ancestor with the Masuriini and Myllaenini due to shared derived morphologies of the lacinia distal teeth with lateral cuticular processes, presence of a unique maxillary palpomere III sensilla, and anterolateral angles of mentum produced. Habitus photographs and illustrations of diagnostic features are provided for the two new genera in order to facilitate future work.     

Freshwater ascomycetes: Aquapoterium pinicola, a new genus and species of Helotiales (leotiomycetes) from Florida

As part of a survey of freshwater ascomycetes in Florida an unusual discomycete fungus belonging in the Helotiales was found on submerged Pinus needles. This fungus is described and illustrated as a new genus and species, Aquapoterium pinicola, based on morphological data. Aquapoterium pinicola is characterized by minute, hyaline apothecia with an excipulum one cell layer thick of parallel hyphae composed of chains of cells narrow at the basal end and enlarged at the apical end and aseptate ascospores that are surrounded by a gelatinous sheath. Analyses of the nuclear ribosomal large subunit DNA sequence data confirmed its placement within the Helotiales but failed to resolve its familial placement.     

Kroswia,a new genus in the Pannariaceae (lichenized ascomycetes)

Abstract:A characteristic, sterile lichen genus with homoiomerous thallus containing terpenoids is described, with one subtropical species, Kroswia crystalliferum sp. nov., occurring scattered in Africa from Kenya south to the Cape, southern India (with Sri Lanka) and Taiwan. Another temperate species, Kroswia gemmascens (Nyl.) comb. nov., is restricted to Eastern Asia. In spite of its gelatinous, homoiomerous thallus, the genus appears to belong to thePannariaceae .     

Fungi on grasses: new species of Ascotaiwania,Diaporthe and Oxydothis (Ascomycetes)

Four new species of ascomycetes, Ascotaiwania pennisetarum sp. nov., Diaporthe appendiculata sp. now., Diaporthe minutis sp. nov., and Oxydothis miscanthiecola sp. nov., are described from senescent culms of grasses in Hong Kong. Ascotaiwania pennisetarum is distinctive from other species in the genus as ascospores are narrower. Diaporthe minutis differs from the most similar Diaporthe species in having ascospores with bipolar mucilaginous pads, while Diaporthe appendiculata differs from other species in having ascospores with both a mucilaginous pad and appendages at both ends. Oxydothis miscanthicola differs from other species in the genus in having long fusiform ascospores, which taper to rounded apices or otherwise differ in shape and size. These new species are compared with existing species and illustrated with interference light micrographs. The Diaporthe species known to posses mucilaginous ascospore appendages are listed.     

New insights in Salicornia L. and allied genera (Chenopodiaceae) inferred from nrDNA sequence data

A phylogenetic analysis was performed based on ITS DNA sequences of fourteen samples from different sources of six species of Salicornia, the three allied genera Arthrocnemum, Sarcocornia and Halocnemum of the same tribe Salicornieae, and other genera of the subfamily Salicornioideae used in previous studies. Bassia hirsuta, Camphorosma monspeliaca (subfamily Chenopodioideae) and four species of Suaeda (subf. Suaedoideae) were chosen as outgroups. Results show that the annual genus Salicornia is a sister group to the perennial genera Sarcocornia, Arthrocnemum and Halocnemum. Moreover, the phylogenetic analysis based on ITS results distinguished two groups of Salicornia species which fitted with ploidy level: one group consisted of diploid species, and the second of tetraploid ones. Sarcocornia and Arthrocnemum are shown to be closely related, even though the species investigated here exhibited an evident distance between their ITS sequences. On the basis of our results, these two genera should be united. Bienertia (already separated as Bienertieae) was confirmed as probable outgroup to the subf. Salicornioideae, while Kalidium (subf. Salicornioideae, tribe Halopeplideae) was an outgroup to the rest of the Salicornioideae (tribe Salicornieae). The group Allenrolfea plus Halocnemum was the most basal of the tribe Salicornieae amongst those investigated in this study. The two samples of Halocnemum strobilaceum used in this work displayed numerous changes (transitions and transversions) in their respective sequences, probably related to their morphological and chorological differentiation. On the basis of our analysis, the most probable basal chromosome number for Salicornieae appears to be 2n = 18. The same number would also be the base number for the annual genus Salicornia and the perennial Arthrocnemum ( + Sarcocornia), with polyploidy arising independently in the two groups.     

Phylogeny of Rhaponticum (Asteraceae, Cardueae-Centaureinae) and related genera inferred from nuclear and chloroplast DNA sequence data: taxonomic and biogeographic implications

BACKGROUND AND AIMS: The precise generic delimitation of the Rhaponticum group is not totally resolved. The lack of knowledge of the relationships between the basal genera of Centaureinae could imply that genera whose position is as yet unresolved could belong to the Rhaponticum group. On the other hand, the affinities among the genera that are considered as members of this group are not well known. The aim of the study is to contribute to the phylogenetic and generic delineation of the Rhaponticum group on the basis of molecular data. METHODS: Parsimony and Bayesian analyses of the combined sequences of one plastid (trnL-trnF) and two nuclear (ITS region and ETS) molecular markers were carried out. The results of these analyses are discussed in the light of the biogeographic history. KEY RESULTS: The Rhaponticum group appears as monophyletic, and closely related to the genus Klasea. The results confirm the preliminary generic delimitation of the Rhaponticum group, with the new incorporation of the genus Centaurothamnus. Ochrocephala is supported as a separate genus from Rhaponticum and, contrary to this, Acroptilon and Leuzea appear as merged into the genus Rhaponticum. Several nomenclatural rearrangements are made in Klasea and Rhaponticum. CONCLUSIONS: The new molecular evidence is consistent with the morphological and karyological data, and suggests particularly coherent biogeographic routes of migration and speciation processes for the genus Rhaponticum. The biogeographic inference proposes a Near East and/or Caucasian origin for the genus. Furthermore, representatives of Rhaponticum could have reached Europe in two different ways: (1) expansion across central Asia to eastern Europe, and (2) expansion through the Near East, North Africa and then to the Iberian Peninsula and the Alps.     

Position of the genera Lycenchelys gill and Lycodapus gilbert in the family Zoarcidae (Perciformes: Zoarcoidei) inferred from molecular genetic analysis

Sequence variation ofthe mitochondrial COI, cytochrome b, and 16S RNA genes, as well as nuclear RNF213 gene was examined in the genera Lycenchelys and Lycodapus with the purpose of determination of their positions in the system of the family Zoarcidae. It was demonstrated that the genus Lycodapus was considerably closer to the generic group of Lycogramminae (Lycogrammoides, Bothrocara, Allolepis, Bothrocarhichthys) than the genus Lycenchelys. However, on the phylogenetic trees both of these genera were located in the clade of the subfamily Lycodinae. Genetic heterogeneity of the genus Lycenchelys, represented by two species groups differing in distribution patterns (northeastern Pacific and Antarctic) and showing more profound differences than the genera of subfamily Lycodinae, was demonstrated.     

Relationship between subfamilies,tribes and genera in iridaceae inferred from chemical characters

Free amino acids and γ-glutamyl peptides have been examined in 22 species of Iridaceae. 3-(3′-Carboxyphenyl)alanine and 3′-carboxyphenylglycine, previously known from the tribes Irideae and Tigridideae in the subfamily Iridodeae have been identified also in the tribe Mariceae of Iridoideae and the genera Bobartia, Orthrosanthus and Libertia of the subfamily Sisyrinchioideae. γ-Glutamyl peptides, previously known from the tribe Irideae, have been found also in the tribe Mariceae, both tribes being from subfamily Iridoideae. γ-Glutamyl-S-methylcysteine, γ-glutamylmethionine and the corresponding sulphoxides are the dominating γ-glutamyl peptides in the genera Dietes, Gynandriris, Moraea (tribe Irideae), Neomarica and Trimezia (tribe Mariceae), whereas γ-glutamyl peptides with non-sulphur amino acids are predominant in genera Ferraria, Hermodactylus, Homeria, Iris, Iridodyctyum and Xiphium (tribe Irideae). Dietes robisoniana, endemic to Lord Howe Island, has the same technical characters as other Dietes species from Southern Africa. The results are discussed in relation to botanical classification of and within the subfamilies Iridoideae and Sisyrinchoideae.     

Parallel evolution of glucosinolate biosynthesis inferred from congruent nuclear and plastid gene phylogenies

The phytochemical system of mustard-oil glucosides (glucosinolates) accompanied by the hydrolytic enzyme myrosinase (beta-thioglucosidase), the latter usually compartmented in special myrosin cells, characterizes plants in 16 families of angiosperms. Traditional classifications place these taxa in many separate orders and thus imply multiple convergences in the origin of this chemical defense system. DNA sequencing of the chloroplast rbcL gene for representatives of all 16 families and several putative relatives, with phylogenetic analyses by parsimony and maximum likelihood methods, demonstrated instead a single major clade of mustard-oil plants and one phylogenetic outlier. In a further independent test, DNA sequencing of the nuclear 18S ribosomal RNA gene for all these exemplars has yielded the same result, a major mustard-oil clade of 15 families (Akaniaceae, Bataceae, Brassicaceae, Bretschneideraceae, Capparaceae, Caricaceae, Gyrostemonaceae, Koeberliniaceae, Limnanthaceae, Moringaceae, Pentadiplandraceae, Resedaceae, Salvadoraceae, Tovariaceae, and Tropaeolaceae) and one outlier, the genus Drypetes, traditionally placed in Euphorbiaceae. Concatenating the two gene sequences (for a total of 3254 nucleotides) in a data set for 33 taxa, we obtain robust support for this finding of parallel origins of glucosinolate biosynthesis. From likely cyanogenic ancestors, the "mustard oil bomb" was invented twice.