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ABSTRACTSeveral species in the Euwallacea fornicatuscomplex have emerged as important pests of woody plants globally, particularly in habitats where they are invasive aliens. These beetles live in obligate symbioses with fungi in the genus Fusarium. In this study, we identified Euwallaceaspp. and their fungal mutualists that have emerged as pests of planted Acacia crassicarpain Riau, Indonesia. Morphological identification and phylogenetic analyses of the mitochondrial cytochrome oxidase csubunit I (COI) gene confirmed that E. similisand E. perbrevisare the most abundant beetles infesting these trees. Multilocus phylogenetic analyses of their fungal mutualists revealed their nonspecific association with six Fusariumspecies. These included F. rekanumand five novel Fusariummutualists within the Fusarium solanispecies complex (FSSC), four of which reside in the Ambrosia FusariumClade (AFC). These new species are described here as F. akasia, F. awan, F. mekan, F. variasi, and F. warna.

Sporothrix, one of the anamorph genera of Ophiostoma, includes the important human pathogen S. schenckiiand various fungi associated with insects and sap stain of wood. A survey of fungi from wood utility poles in South Africa yielded two distinct groups of Sporothrixisolates from different geographical areas. DNA sequence and morphological data derived in this study showed that isolates in these groups represent two novel species in the S. schenckii-O. stenocerasspecies complex. A new species isolated from pine poles and rosebush wood and phylogenetically closely related to S. pallidais described here as Sporothrix stylites. Phylogenetic analyses also confirmed the synonymy of S. albicansand S. niveawith S. pallida. Sporothrix stylitesand S. pallidaalso are related closely to the isolates from soil, previously treated as “environmental” isolates of S. schenckii. Soil isolates are clearly distinct from human isolates of S. schenckii. We describe the former here as Sporothrix humicola. The isolates from eucalypt poles group peripheral to most other species in the S. schenckii-O. stenocerascomplex and are newly described as Sporothrix lignivora. Phylogenetic analyses of sequences of isolates from soil and wood together with those of clinical isolates showed that the human-pathogenic strains form an aggregate of several cryptic species.

Ophiostoma(Ophiostomatales) represents a large genus of fungi mainly known from associations with bark beetles (Curculionidae: Scolytinae) infesting conifers in the northern hemisphere. Few southern hemisphere native species are known, and the five species that consistently occur in the infructescences of Proteaspp. in South Africa are ecologically unusual. Little is known about the vectors of Ophiostomaspp. from Proteainfructescences, however recent studies have considered the possible role of insects and mites in the distribution of these exceptional fungi. In this study we describe a new species of Ophiostomaand a new Sporothrixspp. with affinities to Ophiostoma, both initially isolated from mites associated with Proteaspp. They are described as Ophiostoma gemellussp. nov. and Sporothrix variecibatussp. nov. based on their morphology and comparisons of DNA sequence data of the 28S ribosomal, β-tubulin and internal transcribed spacer (ITS1, 5.8S, ITS2) regions. DNA sequences of S. variecibatuswere identical to those of a Sporothrixisolate obtained from Eucalyptusleaf litter in the same area in which S. variecibatusoccurs in Proteainfructescences. Results of this study add evidence to the view that mites are the vectors of Ophiostomaspp. that colonize Proteainfructescences. They also show that DNA sequence comparisons are likely to reveal additional cryptic species of Ophiostomain this unusual niche.

Ophiostoma galeiformewas described first in 1951 from Larix kaempferiin Scotland, where it was found to be associated with the bark beetles Hy-lurgops palliatus, Dryocoetes autographus,and the ambrosia beetle Trypodendron lineatum.The taxonomy of this fungus has been uncertain because of a lack of sexual structures on the type specimen and contamination of a preserved ex-type culture. The aim of this study was to clarify application of the species name, O. galeiforme,by designating an epitype and to consider phylogenetic relationships of the species. Nineteen isolates resembling O. galeiformefrom different parts of the world were used, including collections from Pinus sylvestrisinfested with Tomicus pi-niperdain Scotland and the contaminated ex-type culture. Morphological characteristics of isolates from Sweden, South Africa, Scotland, Chile and Aus-tria corresponded well with those originally described for O. galeiforme,and an isolate from Scotland is designated as the epitype. A detailed description is provided. Results of interfertility tests showed that O. galeiformeis heterothallic. Analysis of ITS rDNA sequences showed that the isolates representing O. galeiformewere distinct from three morphologically similar isolates from the USA and Mexico, which probably represent an undescribed taxon.

The genus Ophiostomaincludes numerous species of primarily insect-vectored, wood-staining fungi. Several anamorph genera that differ in their micronematous or macronematous conidiogenous cells have been associated with Ophiostomaspecies. Among the former group, Sporothrixis associated with many species and is characterized by conidiogenous cells that arise laterally or terminally from any place on the hyphae and produce nonseptate conidia on sympodially developing denticles. The purpose of this study was to characterize ophiostomatoid isolates with Sporothrixanamorphs recently collected in Austria and Azerbaijan. The isolates were characterized based on comparisons of rDNA and β-tubulin sequence data. Morphology, growth in culture, and sexual reproductive mode were also considered. Phylogenetic analyses of the combined sequence data showed that the isolates formed two distinct groups, one including isolates from Austria and the other isolates from Austria and Azerbaijan. Growth at 25 C and morphology revealed some differences between the two groups, and supported the view that they represent two new species, which we describe here as Ophiostoma fusiformesp. nov. and Ophiostoma lunatumsp. nov. Both these groups phylogenetically were related to, but distinct from, Ophiostoma stenoceras.

Ophiostoma stenocerasis a well-known sapwood-colonizing fungus occurring on some coniferous and hardwood hosts in the Northern Hemisphere. In the Southern Hemisphere, the fungus has been reported only from New Zealand. The human pathogen, Sporothrix schenckii, has been suggested to be the anamorph of O. stenoceras. The aim of this study was to gain a better understanding of the phylogenetic relationship between these two species. The study also provided the opportunity to confirm the identity of some Sporothrixand O. stenoceras-like isolates recently collected from wood and soil around the world. For this purpose, the DNA sequence of internal transcribed spacer (ITS) regions of the ribosomal RNA operon was determined. Isolates of O. nigrocarpum, O. albidum, O. abietinum, O. narcissiand O. ponderosae, all morphologically similar to O. stenoceras, were included in the study. From phylogenetic analyses of the sequence data, four main clades were observed. These represented O. stenoceras, O. nigrocarpumand two separate groups containing isolates of S. schenckii. Our results confirm earlier suggestions that S. schenckiishould be classified within the teleomorph genus Ophiostomabut support studies separating O. stenocerasand S. schenckii. Ophiostoma albidumand O. ponderosaeshould be considered synonyms of O. stenoceras. The status of O. narcissiand O. abietinumneeds further clarification. The two groups within S. schenckiimight represent two species, but this needs to be confirmed. This study represents the first reports of O. stenocerasfrom Colombia, Kenya, Uruguay and South Africa.