Three new species of Iodosphaeria (Xylariomycetidae): I. chiayiensis, I. jinghongensis and I. thailandica

Three fungal specimens (two sexual and one asexual) were collected during fieldwork conducted in China, Taiwan and Thailand. Both sexual morphs share superficial, black ascomata surrounded by flexuous setae; 8-spored, unitunicate, cylindrical asci, with J+, apical ring, and ellipsoidal to allantoid, aseptate, guttulate ascospores. The asexual morph has ceratosporium-like conidia arising from aerial hyphae with a single arm and are usually attached or with 2–3 arms, brown, often with a subglobose to conical cell at the point of attachment. Morphological examinations and phylogenetic analyses of a combined LSU-ITS dataset via maximum likelihood and Bayesian analyses indicated that these three collections were new species. Iodosphaeria chiayiensis (sexual morph), I. thailandica (sexual morph) and I. jinghongensis (asexual morph) are therefore introduced as new species in this study. Iodosphaeria chiayiensis has small, hyaline and ellipsoidal to allantoid ascospores, while I. thailandica has large ascomata, cylindrical to allantoid asci and hyaline to pale brown ascospores.

Gibellula flava sp. nov. (Cordycipitaceae, Hypocreales), a new pathogen of spider from China

Gibellula is an exclusively spider-pathogen genus, with most species immediately recognized by their distinctive conidial state, but also including the teleomorphic states of these fungi that were previously included in the rejected genus Torrubiella. Two sexual specimens and an asexual morph specimen were collected from Anhui Province, China, and were recognized as the same species based on molecular evidence. Its asexual morph differs from Gibellula pulchra, to which it is morphologically similar, in having shorter verrucose conidiophores with slightly smaller metulae, phialides and conidia. Its sexual morph is characterized by producing superficial and elongate ellipsoid small perithecia with short asci on a cream-yellow mycelial mat covering the host. Multi-locus (SSU, LSU, TEF, and RPB1) phylogenetic analyses showed that the specimens belong to a strongly supported subclade, and formed a sister subclade with G. pulchra and Gibellula sp. A combination of morphological characteristics and its phylogenetic placement confirmed that these unique specimens are a new species, which is described as Gibellula flava.

Molecular phylogeny of Aplosporella abexaminans: a novel species revealing the second report of sexual-asexual connection in Aplosporellaceae (Botryosphaeriales) from India

Aplosporella abexaminans, a new sexual morph fungus belongs to family Aplosporellaceae, was discovered on the bark of stem of Murraya koenigii (Rutaceae) and identified by morphological characteristics and analysis of combined ITS and LSU sequence data. This is the second report of a sexual morph with molecular evidence for this genus and the second record of conidiogenesis and chlamydospores associated with the asexual state of this family. It is characterized by its larger ascostromata, locules without ostioles, thinner locule peridium, two to multi-layered, larger asci, surrounded by an additional hyaline sac like structure, larger and hyaline to light olivaceous ascospores, asexual state without conidiomata formation, conidiogenous cells light brown to brown, conidia brown without granular content, smooth and presence of chlamydospores. The sexual morph of Aplosporella abexaminans resembles Bagnisiella and the asexual morph resembles Aplosporella, thus proving the sexual-asexual connection for the second time for this family.

Morphological Variety in Distoseptispora and Introduction of Six Novel Species

Distoseptispora is one of the sporidesmium-like taxa with great variation in asexual morphology and delineation of species. Phylogenetic analyses of four gene regions LSU, ITS, TEF1α, and RPB2 revealed the placement of several sporidesmium-like species in Distoseptispora (Distoseptisporaceae, Distoseptisporales, Sordariomycetes), collected on submerged decaying twigs from streams in China and Thailand. Based on morphological examination and molecular DNA data, six new species, Distoseptispora amniculi, D. atroviridis, D. effusa, D. fusiformis, D. hyalina, and D. verrucosa, are proposed. Among them, D. hyalina is the first sexual morph confirmed in the genus. A new geographical record is reported for D. lignicola in China. Conidial length proved to be of less taxonomic significance for some Distoseptispora species, whereas the type of conidial septa is informative at species level.

Sexual morph specialisation in a trioecious nematode balances opposing selective forces.

The coexistence of different mating strategies, whereby a species can reproduce both by selfing and outcrossing, is an evolutionary enigma that has long intrigued biologists (Darwin, 1877). Theory predicts only two stable mating states : outcrossing with strong inbreeding depression or selfing with weak inbreeding depression. As these two mating strategies are subject to opposing selective forces, mixed breeding systems are thought to be a rare transitory state, yet they have been found to persist even after multiple speciation events. We hypothesise that if each mating strategy plays a distinctive role during the species life history, opposing selective pressures could be balanced, permitting the stable co-existence of selfing and outcrossing sexual morphs. In this scenario, we would expect each sexual morph to be specialised in their respective roles. Here we show, using a combination of behavioural, physiological and gene expression studies, that the selfing (hermaphrodite) and outcrossing (female) sexual morphs of the trioecious nematode Auanema freiburgensis have distinct adaptations optimised for their different roles during the life cycle. A. freiburgensis hermaphrodites are produced under stressful conditions, are specialised for dispersal to new habitat patches and exhibit metabolic and intestinal changes that enable them to meet the energetic cost of dispersal and reproduction. In contrast, A. freiburgensis females are produced in favourable conditions, facilitate rapid population growth and compensate for the lack of reproductive assurance by reallocating resources from intestinal development to robust mate-finding behaviour. The specialisation of each mating system for their role in the life cycle could balance opposing selective forces allowing the stable maintenance of both outcrossing and selfing mating systems in A. freiburgensis.

First reports of the sexual morphs of Diaporthe forlicesenica nom. nov. and Diaporthe goulteri (Diaporthaceae, Diaporthales) revealed by molecular phylogenetics

Diaporthe forlicesenica nom. nov. is proposed for D. dorycnii Dissan., Camporesi & K.D. Hyde, a later homonym of D. dorycnii (Mont.) Sacc. Diaporthe forlicesenica as well as the species D. goulteri have so far only been described in their asexual morphs. In this study, the sexual morphs for these species are recovered for the first time, from the dead branches of Cytisus sp. in Italy and from an unknown host in Thailand. The asexual-sexual morph connections of the species are confirmed by DNA sequence based phylogenetic analyses including the ITS, tef1, tub2 and his loci, supported by morphology. Detailed descriptions, illustrations and molecular data for the taxa are provided.

Phaeoacremonium fusiformostromum sp. nov. and a new record of P. croatiense from China

Phaeoacremonium species are important pathogens with a worldwide distribution and diverse host and are commonly associated with brown wood streaking, dieback and Esca disease of plants and phaeohyphomycosis of humans. In this study, three sexual taxa, representing two Phaeoacremonium species, were collected from dead wood from Guangdong and Guizhou Provinces in China. Based on the morphological characters and phylogenetic analyses of a combined ACT and TUB2 sequence data, they are identified as Phaeoacremonium fusiformostromum sp. nov., and P. croatiense, which is a new record from China with its first sexual morph. Detailed descriptions and illustrations of these two species are provided, and an updated phylogenetic tree for all Phaeoacremonium species is also given.

Introducing a new pleosporalean family Sublophiostomataceae fam. nov. to accommodate Sublophiostoma gen. nov.

Collections of microfungi on bamboo and grasses in Thailand revealed an interesting species morphologically resembling Lophiostoma, but which can be distinguished from the latter based on multi-locus phylogeny. In this paper, a new genus, Sublophiostoma is introduced to accommodate the taxon, S. thailandica sp. nov. Phylogenetic analyses using combined ITS, LSU, RPB2, SSU, and TEF sequences demonstrate that six strains of the new species form a distinct clade within Pleosporales, but cannot be assigned to any existing family. Therefore, a new family Sublophiostomataceae (Pleosporales) is introduced to accommodate the new genus. The sexual morph of Sublophiostomataceae is characterized by subglobose to hemisphaerical, ostiolate ascomata, with crest-like openings, a peridium with cells of textura angularis to textura epidermoidea, cylindric-clavate asci with a bulbous or foot-like narrow pedicel and a well-developed ocular chamber, and hyaline, fusiform, 1-septate ascospores surrounded by a large mucilaginous sheath. The asexual morph (coelomycetous) of the species are observed on culture media.

Additions to the Genus Arthrinium (Apiosporaceae) From Bamboos in China

Arthrinium has a widespread distribution occurring in various substrates (e.g., air, soil debris, plants, lichens, marine algae and even human tissues). It is characterized by the basauxic conidiogenesis in the asexual morph, with apiospores in the sexual morph. In this study, seventeen isolates of Arthrinium were collected in China. Based on their morphology and phylogenetic characterization, four new species (A. biseriale, A. cyclobalanopsidis, A. gelatinosum, and A. septatum) are described and seven known species (A. arundinis, A. garethjonesii, A. guizhouense, A. hydei, A. neosubglobosa, A. phyllostachium and A. psedoparenchymaticum) are identified, of which the sexual morph of three species (A. guizhouense, A. phyllostachium and A. psedoparenchymaticum) and asexual morph of A. garethjonesii are reported for the first time. The detailed descriptions, illustrations and comparisons with related taxa of these new collections are provided. Phylogenetic analyses of combined ITS, LSU, TUB2, and TEF sequence data support their placements in the genus Arthrinium and justify the new species establishments and identifications of known species.

Acrocordiella yunnanensis sp. nov. (Requienellaceae, Xylariales) from Yunnan, China

Acrocordiella yunnanensis sp. nov. is introduced here from dead twigs of an unidentified dicotyledonous host from Xishuangbanna Prefecture, Yunnan Province, China. Phylogenetic analyses based on LSU and ITS sequence data revealed that this new species with a distinct sexual morph belongs to Requienellaceae (Sordariomycetes, Ascomycota). Acrocordiella yunnanensis is closely related to Acrocordiella omanensis in Requienellaceae. This novel taxon is illustrated, described, and a morphology-based key is provided to facilitate the identification of species in Acrocordiella.