Nuclear Subunit Ribosomal RNA Research Articles

A comparison of the community diversity of foliar fungal endophytes between seedling and adult loblolly pines (Pinus taeda)

Fungal endophytes represent one of the most ubiquitous plant symbionts on Earth and are phylogenetically diverse. The structure and diversity of endophyte communities have been shown to depend on host taxa and climate, but there have been relatively few studies exploring endophyte communities throughout host maturity. We compared foliar fungal endophyte communities between seedlings and adult trees of loblolly pines (Pinus taeda) at the same seasons and locations by culturing and culture-independent methods. We sequenced the internal transcribed spacer region and adjacent partial large subunit nuclear ribosomal RNA gene (ITS–LSU amplicon) to delimit operational taxonomic units and phylogenetically characterize the communities. Despite the lower infection frequency in seedlings compared to adult trees, seedling needles were receptive to a more diverse community of fungal endophytes. Culture-free method confirmed the presence of commonly cultured OTUs from adult needles but revealed several new OTUs from seedling needles that were not found with culturing methods. The two most commonly cultured OTUs in adults were rarely cultured from seedlings, suggesting that host age is correlated with a selective enrichment for specific endophytes. This shift in endophyte species dominance may be indicative of a functional change between these fungi and their loblolly pine hosts.

Genetic diversity of Trichomonas vaginalis clinical isolates from Henan province in central China

Trichomonas vaginalis is a flagellated protozoan parasite that infects the human urogenital tract, causing the most common non-viral, sexually transmitted disease worldwide. In this study, genetic variants of T. vaginalis were identified in Henan Province, China. Fragments of the small subunit of nuclear ribosomal RNA (18S rRNA) were amplified from 32 T. vaginalis isolates obtained from seven regions of Henan Province. Overall, 18 haplotypes were determined from the 18S rRNA sequences. Each sampled population and the total population displayed high haplotype diversity (Hd), accompanied by very low nucleotide diversity (Pi). In these molecular genetic variants, 91.58% genetic variation was derived from intra-regions. Phylogenetic analysis revealed no correlation between phylogeny and geographic distribution. Demographic analysis supported population expansion of T. vaginalis isolates from central China. Our findings showing moderate-to-high genetic variations in the 32 isolates of T. vaginalis provide useful knowledge for monitoring changes in parasite populations for the development of future control strategies.

Phylogeny and taxonomy of the genus Abundisporus (Polyporales, Basidiomycota)

Phylogenetic and taxonomic studies of Abundisporus were carried out. Inferred from phylogenies based on DNA sequences of multiple loci including the internal transcribed spacer (ITS) regions, the large subunit nuclear ribosomal RNA gene (nLSU), the small subunit mitochondrial rRNA gene sequences (mtSSU) and the translation elongation factor 1-α gene (tef1), species falling under the current concept of Abundisporus represent a monophyletic lineage, which belongs to the core polyporoid clade. The genus is morphologically characterized by resupinate to pileate basidiocarps with pale umber to deep purplish brown or greyish to umber brown context; a dimitic hyphal structure with yellow to pale brown skeletal hyphae; pale yellowish, non-dextrinoid, ellipsoid basidiospores with slightly thick walls; and tissues that turn brown in KOH. Seven taxa have been recognized in the genus with both morphological and molecular evidence. A new species, A. mollissimus, is described here. The new species is characterized by its soft, perennial, effused-reflexed to pileate basidiocarp, a dimitic hyphal system with dextrinoid, cyanophilous and narrower skeletal hyphae, and ellipsoid basidiospores measuring 4–4.5 × 3–3.5 μm. Illustrated descriptions and a key to all species in this genus are provided.

Resolving Tiarosporella spp. allied to Botryosphaeriaceae and Phacidiaceae

The type species of the genus Tiarosporella, T. paludosa, is epitypified and confirmed as a member of the Botryosphaeriaceae. Based on morphology and DNA sequence data of the large subunit nuclear ribosomal RNA gene (LSU, 28S) and the internal transcribed spacers (ITS) and 5.8S rRNA gene of the nrDNA operon, the genus Tiarosporella is shown to be poly- and paraphyletic. A group of isolates morphologically similar to T. paludosa cluster to the Phacidiaceae (Phacidiales, Leotiomycetes) and we accommodated them in Darkera, a genus associated with needle diseases of conifers, with D. picea introduced as a novel taxon. This new taxon includes isolates occurring on needles of Picea spp. in Europe (Finland, Norway and Switzerland) and differs from D. parca according to a five-locus alignment consisting of ITS, LSU, partial 18S nuclear ribosomal RNA, translation elongation factor 1-alpha and beta-tubulin genes. Four novel genera are introduced for tiarosporella-like fungi, namely Eutiarosporella based on E. tritici on Triticum aestivum from South Africa, Marasasiomyces based on M. karoo on Eriocephalus sp. from South Africa, Mucoharknessia based on M. cortaderiae on Cortaderia selloana from Argentina, and Sakireeta based on S. madreeya on Aristida setacea from India. Together with the genus Botryobambusa, these genera represent a subclade in the Botryosphaeriaceae that is ecologically diverse, occurring on Poaceae, as well as woody hosts, including endophytes, saprobes, and plant pathogens.

Two new genera, Dominikia and Kamienskia, and D. disticha sp. nov. in Glomeromycota

Two new genera, Dominikia and Kamienskia, with five species originally described as Glomus achrum, G. bistratum, G. iranicum, G. minutum and G. perpusillum and two undescribed fungi, D. disticha sp. nov. and D. 211-1 sp. ined., were erected based on morphological studies of spores and mycorrhizal structures and phylogenetic analyses of sequences spanning the small subunit (SSU, partial) nuclear ribosomal RNA gene (nrDNA), the internal transcribed spacer (ITS1, 5.8S, ITS2, full) and the large subunit (LSU, partial) nrDNA. Glomus bistratum and G. perpusillum formed the genus Kamienskia, and the other species were transferred to Dominikia. The main feature linking the seven species is production of hyaline or pale-coloured, small spores in clusters that were not found in field-collected soils to date. Spores of D. disticha are hyaline, globose to subglobose, (28-)40(-57) µm diam., rarely egg-shaped to prolate, 29-34 × 36-52 µm and have a single subtending hypha. The spore wall of D. disticha consists of three hyaline layers: a mucilaginous, short-lived layer 1, forming the spore surface, which stains in Melzer's reagent, a laminate layer 2 and a flexible to semi-flexible layer 3. The subtending hypha is cylindrical to funnel-shaped. D. disticha was found associated with roots of Thinopyrum distichum colonizing maritime sand dunes of the Reserve Rooiels, South Africa, and this is the only site of its occurrence known to date.

Dentipellicula austroafricana sp. nov. supported by morphological and phylogenetic analyses

Dentipellicula austroafricana sp. nov. is described and illustrated from South Africa based on morphological characters and rDNA sequence data. It is characterized by an annual growth habit, resupinate basidiocarps, dense soft spines, a monomitic hyphal structure with non-amyloid, non-dextrinoid and acyanophilous generative hyphae, absence of cystidia, presence of cystidioles, and tiny rough basidiospores (2.4–2.9 × 2–2.2 μm). A molecular study based on the combined ITS (internal transcribed spacer region) and nLSU (the large nuclear ribosomal RNA subunit) dataset supports the new species in Dentipellicula. A key to accepted species of Dentipellicula is provided.

A geographical extension of the North American genus Bothia (Boletaceae, Boletales) to East Asia with a new species B. fujianensis from China

Bothia fujianensis is described as a new species from Fujian Province, a subtropical region of China. It is morphologically characterized by its brown to pale reddish brown basidiomata, pale brown hymenophore, adnate to slightly decurrent, with subreticulations to ridges at the apex of the stipe, relatively longer pleurocystidia, and clavate, subclavate or ventricose cheilocystidia. Molecular phylogenetic analyses using the large subunit nuclear ribosomal RNA loci, DNA nucleotide sequences of the internal transcribed spacer region, and the translation elongation factor 1 alpha also confirmed that B. fujianensis is distinct from B. castanella. The discovery of B. fujianensis in China indicates that Bothia has a much wider geographical distribution range occurring in East Asia and in North America.

Mycoparasitic species of Sphaerellopsis, and allied lichenicolous and other genera.

Species of Sphaerellopsis (sexual morph Eudarluca) are well-known cosmopolitan mycoparasites occurring on a wide range of rusts. Although their potential role as biocontrol agents has received some attention, the molecular phylogeny of the genus has never been resolved. Based on morphology and DNA sequence data of the large subunit nuclear ribosomal RNA gene (LSU, 28S) and the internal transcribed spacers (ITS) and 5.8S rRNA gene of the nrDNA operon, the genus Sphaerellopsis is shown to belong to Leptosphaeriaceae in Dothideomycetes. Sphaerellopsis is circumscribed, and the sexually typified generic name Eudarluca treated as a synonym on the basis that Sphaerellopsis is more commonly used in literature, is the older generic name, and is the morph commonly encountered by plant pathologists in the field. A neotype is designated for Sphaerellopsis filum, and two new species are introduced, S. macroconidialis and S. paraphysata spp. nov. Species previously incorrectly placed in Sphaerellopsis are allocated to Neosphaerellopsis gen. nov. as N. thailandica, and to the genus Acrocalymma, as A. fici. The genus Rhizopycnis is nestled among species of Acrocalymma, and reduced to synonymy based on its morphology and DNA phylogeny, while Acrocalymmaceae is introduced as novel family to accommodate members of this genus in the Dothideomycetes. Furthermore, Sphaerellopsis proved to be phylogenetically closely allied to a lichenicolous complex of phoma-like taxa, for which the new genera Diederichomyces and Xenophoma are established. Several new combinations are introduced, namely D. xanthomendozae, D. ficuzzae, D. caloplacae, D. cladoniicola, D. foliaceiphila, and X. puncteliae combs. nov, while Paraphaeosphaeria parmeliae sp. nov. is newly described.

Investigation and characterization of red thread and pink patch on warm-season turfgrasses in Hainan Province, tropical China

Red thread caused by Laetisaria fuciformis and pink patch caused by Limonomyces roseipellis often occur on many cool-season turfgrass species in temperate regions throughout the world. Incidences of L. fuciformis causing red thread on seashore paspalum (Paspalum vaginatum) and Li. roseipellis causing pink patch on hybrid bermuda grass (Cynodon dactylon × C. transvaalensis) have been reported as new diseases in Hainan Province, a Chinese island with a tropical climate. Field investigations were carried out at 14 golf courses and three college lawns in six cities of Hainan Province from April 2011 to April 2013. Red thread disease was observed on four warm-season turfgrasses throughout the period in all six cities, while pink patch was found on two warm-season turfgrasses in three cities. A total of 21 red thread isolates and five pink patch isolates were collected from these infected turfgrasses. These isolates were identified based on morphological and culture characteristics as well as nucleotide sequences from partial mitochondrial small subunit ribosomal RNA (mtSSU) and nuclear large subunit ribosomal RNA (nuLSU) genes. The optimal temperature for hyphal growth was either 25 or 28 °C for red thread isolates and 28 °C for pink patch isolates. The growth rate of all isolates was significantly less when cultures were grown under continuous light compared to the 12 h light/12 h dark or 24 h dark regimes. Arthroconidia production was optimized under the 12 h light/12 h dark regime. Selected fungal isolates were tested for pathogenicity by inoculating on ‘Seaspray’ seashore paspalum, ‘Princess 77’ bermuda grass (Cynodon dactylon), and ‘Lanyin No 3’ japanese lawngrass (Zoysia japonica) under controlled environmental conditions. All tested L. fuciformis and Li. roseipellis induced foliar blight in the turfgrass species.

Studies on Wrightoporia from China 3. Wrightoporia subavellanea sp. nov. based on morphological characters and rDNA sequence data

Wrightoporia subavellanea sp. nov. is described and illustrated from southern China on the basis of morphological characters and molecular data. It is characterized by an annual growth habit, resupinate basidiocarps with white rhizomorphs, large pores, narrow and strongly dextrinoid skeletal hyphae, broadly ellipsoid to subglobose, thick-walled, finely asperulate and strongly amyloid basidiospores (3.8–4.2 × 2.8–3.2 µm), and presence of gloeoplerous hyphae in trama. A molecular study based the combined ITS (internal transcribed spacer region) and nLSU (the large nuclear ribosomal RNA subunit) dataset supported the position of the new species in Wrightoporia. A key to accepted species of Wrightoporia in China is provided.

<p class="p0" style="margin-top: 0pt; margin-bottom: 6pt;">Cibaomyces, a new genus of Physalacriaceae from East Asia<!--EndFragment-->

A new genus in Physalacriaceae, Cibaomyces, typified by C. glutinis, is described using morphological and molecular evidence. Cibaomyces is morphologically characterized by the combination of the following characters: basidioma small to medium-sized, collybioid to tricholomatoid; pileus viscid; hymenophore sinuate to subdecurrent, relatively distant, with brown lamellar edge; stipe sticky and densely covered with felted squamules; basidiospores thin-walled, ornamented with finger-like projections; cystidia nearly cylindrical, thin-walled, often heavily incrusted. Molecular phylogenetic analyses using DNA nucleotide sequences of the internal transcribed spacer region and the large subunit nuclear ribosomal RNA loci indicated that Cibaomyces was related to Gloiocephala, Laccariopsis and Rhizomarasmius. A description, line drawings, phylogenetic placement and comparison with allied taxa are presented.

Foliicolous fungi from Arctostaphylos pungens in Mexico.

Arctostaphylos pungens "Manzanita" is an important shrub in the southwestern USA, and northern and central Mexico. Manzanita bears apple-like fruit that is utilised for a range of edible products. Over the past two years, several foliar disease problems were noted on this host in the San José de Gracia region of Mexico. The aim of the present study was to elucidate their identity through the analysis of morphological characters and DNA phylogeny (based on the large subunit nuclear ribosomal RNA gene and the ITS spacers and the intervening 5.8S rRNA gene of the nrDNA operon) of the fungi associated with these disease symptoms. Three species are newly described: Phaeococcomyces mexicanus sp. nov., a presumed epiphyte, and two species associated with leaf spots and defoliation, namely Coccomyces arctostaphyloides sp. nov. and Passalora arctostaphyli sp. nov. A fourth species is also associated with leaf spots and tip dieback is Harknessia arctostaphyli, for which an epitype is designated. All species can co-occur on the same shrub, which adds to the stress experienced by the plant, leading to further defoliation and dieback.

First molecular characterization of Cryptosporidium and Giardia from bovines (Bos taurus and Bubalus bubalis) in Sri Lanka: unexpected absence of C. parvum from pre-weaned calves

BackgroundThe genetic characterization of Cryptosporidium and Giardia has important implications for investigating their epidemiology and underpins their control. We undertook the first molecular epidemiological survey of domestic bovids in selected regions of Sri Lanka to establish whether they excreted Cryptosporidium and/or Giardia with zoonotic potential.MethodsFaecal samples were collected from dairy calves (n = 340; Bos taurus; < 3 months of age; weekly sampling for six weeks) and water buffaloes (n = 297; Bubalus bubalis; <6 months and ≥6 months of age; one sampling) from seven different farms in Sri Lanka. Genomic DNAs were extracted from individual faecal samples and then tested for the presence of parasite DNA using a PCR-based mutation scanning-targeted sequencing-phylogenetic approach, employing genetic markers within the small subunit of nuclear ribosomal RNA and 60 kDa glycoprotein genes (designated pSSU and pgp60, respectively) for Cryptosporidium, and within the triose phosphate isomerise (ptpi) gene for Giardia.ResultsBased on pSSU sequence data, C. bovis, C. ryanae and six new genotypes that were genetically similar but not identical to C. andersoni (n = 1), C. bovis (n = 1), C. ryanae (n = 3) and C. suis (n = 1) were recorded in cattle. For pSSU, two other, new genotypes were defined in water buffalo, which were genetically most similar to Cryptosporidium genotypes recorded previously in this host species in other countries including Australia. Consistent with the findings for pSSU, no species or genotypes of Cryptosporidium with zoonotic potential were detected using pgp60. Based on ptpi sequence data, G. duodenalis assemblages A and E were detected in four and 137 samples from cattle, respectively, and assemblage E in two samples from water buffaloes.ConclusionsThe present study showed that C. parvum, the most commonly reported zoonotic species of Cryptosporidium recognised in bovine calves globally, was not detected in any of the samples from pre-weaned calves tested in the present study. However, eight new genotypes were recorded. Future studies of different host species in various regions are required to investigate the molecular epidemiology of cryptosporidiosis and giardiasis in Sri Lanka and neighbouring countries in South Asia.

A phylogenetic re-evaluation of Arthrinium.

Although the genus Arthrinium (sexual morph Apiospora) is commonly isolated as an endophyte from a range of substrates, and is extremely interesting for the pharmaceutical industry, its molecular phylogeny has never been resolved. Based on morphology and DNA sequence data of the large subunit nuclear ribosomal RNA gene (LSU, 28S) and the internal transcribed spacers (ITS) and 5.8S rRNA gene of the nrDNA operon, the genus Arthrinium is shown to belong to Apiosporaceae in Xylariales. Arthrinium is morphologically and phylogenetically circumscribed, and the sexual genus Apiospora treated as synonym on the basis that Arthinium is older, more commonly encountered, and more frequently used in literature. An epitype is designated for Arthrinium pterospermum, and several well-known species are redefined based on their morphology and sequence data of the translation elongation factor 1-alpha (TEF), beta-tubulin (TUB) and internal transcribed spacer (ITS1, 5.8S, ITS2) gene regions. Newly described are A. hydei on Bambusa tuldoides from Hong Kong, A. kogelbergense on dead culms of Restionaceae from South Africa, A. malaysianum on Macaranga hullettii from Malaysia, A. ovatum on Arundinaria hindsii from Hong Kong, A. phragmites on Phragmites australis from Italy, A. pseudospegazzinii on Macaranga hullettii from Malaysia, A. pseudosinense on bamboo from The Netherlands, and A. xenocordella from soil in Zimbabwe. Furthermore, the genera Pteroconium and Cordella are also reduced to synonymy, rejecting spore shape and the presence of setae as characters of generic significance separating them from Arthrinium.

Divergence and species discrimination in freshwater bryozoans (Bryozoa: Phylactolaemata)

We explored the suitability of nuclear and mitochondrial ribosomal markers [small subunit nuclear ribosomal RNA gene, large subunit nuclear ribosomal RNA gene, and a region spanning partial small mitochondrial ribosomal RNA subunit, four transfer RNA genes, and partial large mitochondrial ribosomal RNA subunit (referred to as rrnS-rrnL)] for resolving patterns of diversification of 27 freshwater bryozoan species (class: Phylactolaemata) and evaluated the utility of statoblast ultrastructural features and molecular phylogenies for species discrimination in the Fredericellidae and Plumatellidae. Molecular data identified Plumatella fruticosa as distinct from the rest of the plumatellids, rendering the latter polyphyletic. rrnS-rrnL was the most suitable marker for species discrimination and identified two undescribed species of Plumatella and at least two undescribed species of Fredericella. Lack of wide dispersal by fredericellid statoblasts may underlie the observed propensity for cryptic speciation and phylogeographical structure in Fredericella. Conversely, the strong dispersal potential of plumatellid statoblasts may mediate efficient gene flow between distant populations and explain the relatively low intraspecific divergence and lack of evidence for cryptic speciation. We show that species identification based on external features of statoblasts can be problematic in both genera, including for a putatively highly invasive, biofouling species, Plumatella vaihiriae, thereby highlighting the utility of rrnS-rrnL sequences for species barcoding. © 2013 The Linnean Society of London

Morphological and molecular evidence for a new species of Rhodotus from tropical and subtropical Yunnan, China

Rhodotus has been regarded as a monotypic genus, consisting of only one species, R. palmatus, for a long time. Morphological and phylogenetic studies were carried out on collections of Rhodotus from temperate, subtropical and tropical China. Our phylogenetic analysis of DNA sequences of three loci (the internal transcribed spacer, the large subunit nuclear ribosomal RNA, and the translation elongation factor-1 alpha) revealed that there are two phylogenetic species in the northern hemisphere, which is in concordance with morphological traits, supporting the division of Rhodotus into two distinct species. Rhodotus asperior is described as a new species that differs phenotypically from R. palmatus in its broadly ellipsoid to subglobose, more roughened basidiospores, longer cheilocystidia with slightly thickened wall, and its occurrence in tropical and subtropical environments. The discovery of this new taxon indicates Rhodotus has a wider distribution than previously thought.

Homortomyces gen. nov., a new dothidealean pycnidial fungus from the Cradle of Humankind

Homortomyces is introduced as a new coelomycetous genus associated with leaf spots onCombretum erythrophyllum trees growing near and around the Sterkfontein caves, Maropeng, South Africa. Based on its transversely septate, brown conidia, the presence of paraphyses, and percurrent proliferation of the conidiogenous cells, the genus resembles Stilbospora (Melanoconidaceae, Diaporthales). It is distinct in having pycnidial condiomata, conidia lacking mucoid sheaths, and becoming muriform when mature. Its morphology and phylogenetic placement based on analyses of sequence data for the large subunit nuclear ribosomal RNA gene (LSU, 28S) as well as the ITS and 5.8S rRNA gene of the nrDNA operon, show that Homortomyces represents a novel genus in Dothideomycetes, although its familial relationships remain unresolved.

How important are conidial appendages?

The genus The genus Dinemasporium is used as a case study to evaluate the importance of conidial appendages for generic level classification of coelomycetous fungi. Based on morphology and sequence data of the large subunit nuclear ribosomal RNA gene (LSU, 28S) and the internal transcribed spacers and 5.8S rRNA gene of the nrDNA operon, the genus Dinemasporium is circumscribed, and an epitype designated for D. strigosum, the type of the genus. A further five species are introduced in Dinemasporium, namely D. pseudostrigosum (isolated from Triticum aestivum, Germany and Stigmaphyllon sagraeanum, Cuba), D. americana (soil, USA), D. polygonum (Polygonum sachalinense, Netherlands), D. pseudoindicum (soil, USA), and D. morbidum (human sputum, Netherlands and hare dung, New Zealand). Brunneodinemasporium, based on B. brasiliense, is introduced to accommodate Dinemasporium-like species with tightly aggregated brown conidiogenous cells, and pale brown conidia. Dendrophoma (= Amphitiarospora) is reinstated as distinct from Dinemasporium, and an epitype designated for D. cytisporoides, characterised by its superficial, stipitate to cupulate conidiomata, and small conidia with two polar, tubular, exogenous appendages. The genus Stauronema is reduced to synonymy under Dinemasporium. Pseudolachnea (1-septate conidia) is supported as distinct from Dinemasporium (aseptate conidia), and P. fraxini introduced as a novel species. Taxa in this generic complex differ by combination of morphological characters of conidiomata, setae, conidia and appendages. Appendage morphology alone is rejected as informative at the generic level.

Molecular detection of Cryptosporidium cuniculus in rabbits in Australia

In the United Kingdom, rabbits have been reported to harbour genotypes of Cryptosporidium (now recognized as C. cuniculus) identical to those from human patients exhibiting symptoms of cryptosporidiosis. The high density of rabbits in many regions of Australia, including both rural and urban as well as natural water catchments areas, and the absence of any information on Cryptosporidium from lagomorphs in this country stimulated the present study. We undertook an epidemiological study that genetically characterized Cryptosporidium from rabbits from four locations in Victoria by PCR-coupled sequencing and phylogenetic analysis of sequence data for loci within the small subunit of nuclear ribosomal RNA (SSU; for specific identification) and the 60kDa glycoprotein gene (gp60; for genotypic/subgenotypic identification). Cryptosporidium was detected in 12 (6.8%) of 176 individual faecal samples. For SSU, all 12 sequences were identical to each other and to that of C. cuniculus. For pgp60, all corresponding sequences matched the known genotype Vb, and were classified as subgenotype VbA23R3 (n=11) and VbA26R4 (n=1), which are both new records. Present evidence indicates that genotype Vb is limited to rabbits; however, it would be premature to conclude that this genotype is not zoonotic. Future studies should focus on the zoonotic potential of C. cuniculus from rabbits and a wide range of yet unstudied animals. (Nucleotide sequences reported in this paper are available in the GenBank database under accession nos. HM852431–HM852433).

Multilocus phylogenetics show high levels of endemic fusaria inhabiting Sardinian soils (Tyrrhenian Islands)

The Mediterranean island of Sardinia is well known for high levels of vascular plant diversity and endemism, but little is known about its microbial diversity. Under the hypothesis that Fusarium species would show similarly high diversity, we estimated variability in Fusarium species composition among 10 sites around the island. Markers previously adopted for multilocus sequence typing (MLST) were used to determine multilocus DNA sequence haplotypes for 263 Fusarium isolates. In addition portions of the translation elongation factor 1-alpha and second largest RNA polymerase subunit genes were sequenced for all isolates. The intergenic spacer (IGS) region of the nuclear ribosomal RNA gene repeat was sequenced for members of the F. oxysporum species complex (FOSC), and a portion of the nuclear ribosomal RNA gene repeat comprising the internal transcribed spacer (ITS) and part of the large nuclear ribosomal RNA subunit was sequenced for members of the F. solani species complex (FSSC). Seventy-three multilocus haplotypes were identified among the 263 isolates typed, of which 48 represented FOSC and FSSC. Thirty-seven of 48 FOSC two-locus and FSSC three-locus haplotypes had not been observed previously. The 38 non-FOSC/FSSC fusaria comprised 25 haplotypes distributed among 10 species, five of which appear to represent novel, phylogenetically distinct species. In general newly discovered haplotypes were restricted to one or a few sites. All FSSC isolates represented new haplotypes in phylogenetic species FSSC 5 and 9, which differ from the phylogenetic species dominant in soils worldwide. No obvious correlations were found between haplotype diversity and geospatial or habitat distribution. Overall these results indicate a high degree of Fusarium genetic diversity on multiple geographic scales within Sardinia. These results contrast with recent work showing that common, cosmopolitan species dominate Sardinia’s Trichoderma biodiversity. All data are available for access and viewing from the FUSARIUM-ID database.