Metschnikowia santaceciliae,Candida hawaiiana,and Candida kipukae,three new yeast species associated with insects of tropical morning glory

A new haplontic heterothallic species of Metschnikowia and two related asexual yeast species were discovered in morning glory flowers and associated insects. Metschnikowia santaceciliae came from Conotelus (Coleoptera: Nitidulidae) and other insect species associated with flowers of Ipomoea indica (purple morph) in Costa Rica. Candida hawaiiana and Candida kipukae were found in I. indica (syn. I. acuminata) and its insects in Hawai'i, and the former was also isolated in a specimen of Conotelus collected on Merremia tuberosa (Convolvulaceae) in Costa Rica. The three species have nearly identical physiological profiles, typical of the genus Metschnikowia. The sequences of the D1/D2 domains of their large subunit ribosomal DNA confirm that the species belong to the Metschnikowia clade, even though they share a very low degree of inter-relatedness. M. santaceciliae is a sister species to Metschnikowia continentalis. C. kipukae is a basal member of the large-spored Metschnikowia subclade, and C. hawaiiana has a weak affinity to Metschnikowia agaves. Two of the three species appear to be endemic. The type cultures are: Metschnikowia santaceciliae, strains UWO(PS)01-517a1=CBS 9148=NRRL Y-27475 (h(+, holotype) and UWO(PS)01-520a1=CBS 9149=NRRL Y-27476 (h-, isotype); Candida hawaiiana, strain UWO(PS)91-698.3=CBS 9146=NRRL Y-27473; Candida kipukae, strain UWO(PS)00-669.2=CBS 9147=NRRL Y-27474.     

Metschnikowia lochheadii and Metschnikowia drosophilae, two new yeast species isolated from insects associated with flowers

Two new haplontic heterothallic species of Metschnikowia were isolated from floricolous insects and flowers. Metschnikowia lochheadii was recovered from insects found in various flowers on the Hawaiian Islands of Kauai and Maui, and from Conotelus sp. (Coleoptera: Nitidulidae) in northwestern Guanacaste Province, Costa Rica. The morphology, physiology, and sexual cycle are typical of the large-spored Metschnikowia species, and the partial ribosomal DNA large subunit (D1D2) sequences suggest that the new species is most closely related to Candida ipomoeae. Metschnikowia lochheadii is nearly indistinguishable from its ascogenous relatives and conjugates freely with Metschnikowia continentalis, forming sterile asci. It also exhibits asymmetric mating with Metschnikowia hawaiiensis. Metschnikowia drosophilae was found in morning glory (Ipomoea sp.) flowers and associated Drosophila bromeliae on Grand Cayman Island. Its nutritional profile is atypical of the genus, being the only species that does not utilize sucrose or maltose as carbon sources, and one of the few that does not utilize melezitose. D1D2 sequences show that Metschnikowia drosophilae is a sister species to Candida torresii, to which it bears considerable similarity in nutritional profile. The type cultures are: Metschnikowia lochheadii, strains UWO(PS)00-133.2 = CBS 8807 (h+, holotype) UWO(PS)99-661.1 = CBS 8808 (h-, isotype); and Metschnikowia drosophilae, strains UWO(PS)83-1135.3 = CBS 8809 (h+, holotype) and UWO(PS)83-1143.1 = CBS 8810 (h-, isotype).     

Metschnikowia hawaiiensis sp. nov., a heterothallic haploid yeast from Hawaiian morning glory and associated drosophilids

A new haploid, heterothallic yeast species was isolated repeatedly from morning glory (Ipomoea acuminata) flowers and from two associated drosophilid species, Scaptomyza calliginosa and Drosophila floricola, in a Hawaiian kipuka. Haploid strains of this organism multiply asexually by budding and, under nutrient deprivation, by the formation of long germ tubes that develop into branching true mycelia. Mating compatibility is controlled by two alleles of a single locus. Plasmogamy between compatible strains is followed by the development of very large elongate asci bearing vestiges of the zygotes and the formation in each ascus of two unusually large aciculate ascospores similar to those formed by members of the genus Metschnikowia. Membership in the genus Metschnikowia is supported by the physiological profile of the yeast, which is typical of the genus but not identical to the profile of any previously described species. The name Metschnikowia hawaiiensis is proposed to emphasize the geographic origin of the new species, not its habitat, which has not been determined precisely. The holotype strain of M. hawaiiensis is strain UWO(PS) 87-2167.2 (= ATCC 76059 = CBS 7432), and the isotype strain is strain UWO(PS) 87-2203.2 (= ATCC 76058 = CBS 7433).     

Speciation in the large-spored Metschnikowia clade and establishment of a new species, Metschnikowia borealis comb. nov

The reproductive boundaries among species in the large-spored Metschnikowia clade were studied by prototrophic recombinant selection, electrophoretic karyotyping, mitochondrial DNA restriction analysis, and DNA sequence analysis. Inviable ascospores arose from crosses between the two varieties of Metschnikowia continentalis, indicating that they should be recognized as separate species. Prototrophic recombinants were recovered from crosses between auxotrophic mutants of Metschnikowia borealis, M. continentalis, Metschnikowia lochheadii, Metschnikowia sp. UWO(PS)00-154.1, and Candida ipomoeae, showing that some genetic exchange is possible in spite of the sterility of the asci formed in interspecific crosses. Metschnikowia hawaiiensis, although capable of ascus formation when its h(-) mating type is crossed with the h(+) mating type of the other species, did not give rise to recombinants. In the other species, some recombinants acquired the ability to form asci directly from single cells. These often contained the chromosomes of both parents, suggesting formation of allodiploid hybrids. Other recombinants behaved as haploids and were similar to one parent except for having inherited the selectable wild-type allele from the other parent. In most, but not all cases, inheritance of the mitochondrial genome was uniparental and correlated with the inheritance of the nuclear chromosome complement. In some cases, what appeared to be a recombinant mitochondrial genome was observed. Phylogenies derived from the sequences of various DNA regions were not congruent, indicating that hybridization may have taken place in nature as the large-spored species diverged from their common ancestor. Further evidence that C. ipomoeae arose from a natural recombination event was obtained, but a pair of Metschnikowia species that might represent derived forms of the parents could not be identified conclusively. C. ipomoeae and most of its closely related Metschnikowia species contained a group-II intron in the mitochondrial small-subunit ribosomal gene. The intron was absent in M. borealis, M. hawaiiensis, and other species in the genus Metschnikowia.     

Kodamaea kakaduensis and Candida tolerans, two new ascomycetous yeast species from Australian Hibiscus flowers.

Two new yeast species were isolated from flowers of Hibiscus species in Eastern and Northern Australia. Kodamaea kakaduensis is heterothallic, haploid, and similar to other Kodamaea species and to Candida restingae. Buds are often produced on short protuberances, and a true mycelium is formed. The new species differs from others by the assimilation of trehalose, melezitose, and xylitol, and is reproductively isolated. The cells of Candida tolerans are small and a pseudomycelium is formed. The carbon and nitrogen assimilation pattern is reminiscent of that of Zygosaccharomyces rouxii but the two are not closely related. Sequences of the D1/D2 domain of large subunit ribosomal DNA confirm the membership of K. kakaduensis in the genus Kodamaea and indicate that C. tolerans belongs to the Clavispora-Metschnikowia clade, with a moderate relatedness to Candida mogii. The type strains are: K. kakaduensis, UWO(PS)98-119.2 (h+, holotype, CBS 8611) and UWO(PS)98-117.1 (h-, isotype, CBS 8612); and C. tolerans, UWO(PS)98-115.5 (CBS 8613).     

Catching speciation in the act: Metschnikowia bowlesiae sp. nov., a yeast species found in nitidulid beetles of Hawaii and Belize

We describe the species Metschnikowia bowlesiae sp. nov. based on the recovery of six isolates from Hawaii and Belize. The species belongs to the Metschnikowia arizonensis subclade of the large-spored Metschnikowia clade. The isolates are haploid and heterothallic. Both Hawaiian strains had the mating type h ⁺ and the Belizean strains were h ^?. Paraphyletic species structures observed in some ribosomal DNA sequence analyses suggest that M. bowlesiae sp. nov. might represent an intermediate stage in a succession of peripatric speciation events from Metschnikowia dekortorum to Metschnikowia similis and might even hybridize with these species. The type of M. bowlesiae sp. nov. is strain UWOPS 04-243x5 (CBS 12940^T, NRRL Y-63671) and the allotype is strain UWOPS 12-619.1 (CBS 12939^A, NRRL Y-63670).     

Eleven new species of Sugiyamaella and Candida from forest habitats

Eleven new yeasts from forest habitats are described from nucleotide sequence analysis of the nearly entire large subunit rRNA gene, ITS1-5.8S-ITS2 rRNA gene, mitochondrial small subunit rRNA gene, and the cytochrome oxidase II gene. All are members of the Sugiyamaella clade. Three are heterothallic species of Sugiyamaella and eight species are assigned to Candida. The Sugiyamaella species are: Su. americana sp. nov., type strain NRRL YB-2067 (CBS 10352), mating type a, and isotype NRRL YB-4197 (CBS 10353), mating type alpha; Su. chiloensis sp. nov., type strain NRRL Y-17646 (CBS 8168), mating type a, and isotype NRRL Y-27101 (CBS 5927), mating type alpha, anamorph Ca. bertae; Su. japonica sp. nov., type strain NRRL YB-2788 (CBS 10354), diploid, NRRL YB-2764 (CBS 10355), mating type a, and NRRL YB-2799 (CBS 10356), mating type alpha. The Candida species with type strains are: Ca. boreocaroliniensis sp. nov. NRRL YB-1835 (CBS 10344), Ca. floridensis sp. nov. NRRL YB-3827 (CBS 10350), Ca. grinbergsii sp. nov. NRRL Y-27117 (CBS 5924), Ca. lignohabitans sp. nov. NRRL YB-1473 (CBS 10342), Ca. marilandica sp. nov. NRRL YB-1847 (CBS 10346), Ca. marionensis sp. nov. NRRL YB-1336 (CBS 10341), Ca. neomexicana sp. nov. NRRL YB-2450 (CBS 10349), and Ca. pinicola sp. nov. NRRL YB-2263 (CBS 10348).     

Metschnikowia noctiluminum sp. nov., Metschnikowia corniflorae sp. nov., and Candida chrysomelidarum sp. nov., isolated from green lacewings and beetles

Fourteen yeast isolates belonging to the Metschnikowia clade were isolated from the digestive tracts of lacewings (Neuroptera: Chrysopidae), soldier beetles and leaf beetles (Coleoptera: Cantharidae and Chrysomelidae), and a caddisfly (Trichoptera: Hydropsychidae). The insect hosts were associated with sugary substances of plants, a typical habitat for yeasts in this clade. Based on DNA sequence comparisons and phenetic characters, the yeasts were identified as Candida picachoensis, Candida pimensis, and four undescribed taxa. Among the undescribed taxa, three yeasts were distinguished from one another and from other described taxa by nucleotide differences in the ribosomal DNA repeat, which were sufficient to consider them as new species. Two of the novel yeast species are described as Metschnikowia noctiluminum (NRRL Y-27753^T) and M. corniflorae spp. nov. (NRRL Y-27750^T) based in part on production of needle-shaped ascospores, which are found in most Metschnikowia species. Sexual reproduction was not observed in the third new yeast, Candida chrysomelidarum sp. nov. (NRRL Y-27749^T). A fourth isolate, NRRL Y-27752, was not significantly distinct from Metschnikowia viticola and Candida kofuensis to be described as a new species. Phylogenetic analysis of the D1/D2 loop sequences placed M. noctiluminum within the M. viticola clade, while C. chrysomelidarum was a sister taxon of Candida rancensis. Metschnikowia corniflorae was phylogenetically distinct from other new species and fell outside of the large-spored Metschnikowia group.     

Metschnikowia fructicola, a new ascosporic yeast with potential for biocontrol of postharvest fruit rots

A new ascosporic yeast, Metschnikowia fructicola (type strain NRRL Y-27328, CBS 8853), is described and was isolated from grapes grown in central Israel. Preliminary tests indicate the new species has biocontrol activity against Botrytis rot of stored grapes. Phylogenetic analysis of domain D1/D2 26S rDNA sequences showed M. fructicola to be a sister species of M. pulcherrima.     

On the biogeography of yeasts in the Wickerhamiella clade and description of Wickerhamiella lipophila sp. nov., the teleomorph of Candida lipophila

We describe the new yeast species Wickerhamiella lipophila, the teleomorph of Candida lipophila, a haploid heterothallic yeast previously isolated from insects associated with morning glories in Hawaii. Both mating types were recovered in the eastern region of Maui, and a single strain was found in the Waimea region of Kauai. We reexamined the mating compatibility of the several strains of Candida lipophila previously collected on the island of Hawaii and found them to be fertile mating types that had been overlooked because of the unpredictability of mating and ascus formation. The type culture of Candida lipophila [UWO(PS)91-681.3 = CBS 8458, h+] is transferred to the genus Wickerhamiella, and strain UWO(PS)00-340.1 (CBS 8812, h-) is designated as isotype. Also found on Maui and Kauai were strains of Candida drosophilae that produced a strong extracellular protease. An update on the global distribution of members of the Wickerhamiella clade is given.     

New species and new combinations in the yeast genera Kregervanrija gen. nov., Saturnispora and Candida

Analysis of nucleotide sequences from the domains 1 and 2 of the large-subunit rDNA demonstrated species of the Pichia fluxuum clade to be phylogenetically isolated, and domains 1 and 2 and internal transcribed spacer rDNA sequence analyses of strains phenotypically identified as P. fluxuum resulted in the discovery of three new species. From this work, the following new genus, new species, and new combinations are proposed: Kregervanrija gen. nov.; type species Kregervanrija fluxuum comb. nov. (type strain NRRL YB-4273, CBS 2287); Kregervanrija delftensis comb. nov. (type strain NRRL Y-7119, CBS 2614); Kregervanrija pseudodelftensis sp. nov. (type strain NRRL Y-5494, CBS 10105); Saturnispora besseyi comb. nov. (NRRL YB-4711, CBS 6343); Saturnispora mendoncae sp. nov. (type strain NRRL Y-11515, CBS 5620); and Candida abiesophila sp. nov. (type strain NRRL Y-11514, CBS 5366).     

Candida riodocensis and Candida cellae, two new yeast species from the Starmerella clade associated with solitary bees in the Atlantic rain forest of Brazil

Two new ascomycetous yeast species belonging to the Starmerella clade were discovered in nests of two solitary bee species in the Atlantic rain forest of Brazil. Candida riodocensis was isolated from pollen-nectar provisions, larvae and fecal pellets of nests of Megachile sp., and Candida cellae was found in pollen-nectar provisions of Centris tarsata. Analysis of the sequences of the D1/D2 large-subunit ribosomal DNA showed that C. riodocensis is phylogenetically related to C. batistae, and the closest relative of C. cellae is C. etchellsii. The type strains are C. riodocensis UFMG-MG02 (=CBS 10087(T) = NRRL Y-27859(T)) and C. cellae UFMG-PC04 (=CBS 10086(T) = NRRL Y-27860(T)).     

<Emphasis Type="Italic">Metschnikowia viticola</Emphasis> sp. nov., a new yeast species from grape

Two yeast strains, producing needle-shaped ascospores under suitable conditions, were isolated from grapes grown in Hungary. Based on these two strains, Metschnikowia viticola (type strain NCAIM Y.01705, CBS 9950, JCM 12561) is proposed as a new yeast species. Considering its phenotypic features, the restriction fragment patterns of 18S rDNA and the sequence of the D1/D2 domain of 26S rDNA, the proposed new species is closely related to Candida kofuensis.     

New species and a new combination in the <Emphasis Type="Italic">Hyphopichia</Emphasis> and <Emphasis Type="Italic">Yarrowia</Emphasis> yeast clades

Three new species of Candida and a new combination in the genus Hyphopichia are proposed from phylogenetic analysis of nucleotide divergence in domains D1/D2 of the large subunit (26S) rDNA. The new taxa and their type strains are the following: Candida bentonensis sp. nov. (NRRL YB-2364, CBS 9994), Candida hispaniensis sp. nov. (NRRL Y-5580, CBS 9996), Candida pseudorhagii sp. nov. (NRRL YB-2076, CBS 9998) and Hyphopichia heimii comb. nov. (NRRL Y-7502, CBS 6139), basionym Pichia heimii Pignal. Phylogenetic analysis placed C. pseudorhagii and H. heimii in the Hyphopichia clade whereas C. bentonensis and C. hispaniensis are members of the Yarrowia clade.     

Metschnikowia kunwiensis comb. nov., the teleomorph of Candida kunwiensis

The teleomorph of Candida kunwiensis Hong, Bae, Herzberg, Titze, Lachance, Metschnikowia kunwiensis, is described. Repeated attempts to obtain ascospore formation succeeded using modified V8 sporulation media and extended incubation times. The asci are ovoid, with only a small protrusion caused by the spore(s). The species is diplontic, possibly homothallic, with one or two ascospores per ascus. Aside from having atypical ovoid asci, the acicular shape of the spores is characteristic of the genus Metschnikowia. The type strain is CBS 9676(T).     

Ogataea falcaomoraisii sp. nov., a sporogenous methylotrophic yeast from tree exudates

Thirteen strains of a new ascospore-forming, methanol-assimilating yeast species were isolated from sap exudates of Sclerolobium sp. (carvoeiro) in two forest fragments in the state of Toncantins, Brazil, and from Hymenaea courbaril (guapinol, jatobá) in Guanacaste Province, Costa Rica. Analysis of the sequences of the D1/D2 large-subunit ribosomal DNA showed that the species belongs to the genus Ogataea (syn. Pichia), and it was described as Ogataea falcaomoraisii. The closest relatives are Candida ortonii and C. nemodendra. The type culture is UFMG-T264-1T (= CBS 9814T = NRRL Y-27756).     

Cryptococcus bestiolae and Cryptococcus dejecticola, two new yeast species isolated from frass of the litchi fruit borer Conopomorpha sinensis Bradley

Two new yeast species, Cryptococcus bestiolae and Cryptococcus dejecticola, were discovered in the frass of the litchi fruit borer Conopomorpha sinensis Bradley. The yeasts utilize inositol, hydrolyze urea, produce starch-like substance, and contain CoQ10. Phylogenetic analyses of D1/D2 26S rDNA and internal transcribed spacer (ITS) sequences indicate that the yeasts are closely related to Bullera dendrophila and an undescribed species of Cryptococcus (strain CBS 8507). The two new species differed from each other by 17 nucleotides in the D1/D2 region and by 68 nucleotides in the ITS region. Cryptococcus bestiolae is a sister species to Cryptococcus sp. CBS 8507, from which it differs by eight nucleotides in the D1/D2 region and 59 nucleotides in the ITS region. Cryptococcus dejecticola and B. dendrophila differed by 13 nucleotides in the D1/D2 and 57 nucleotides in the ITS region. Cryptococcus bestiolae and Cr. dejecticola formed with B. dendrophila a well defined clade consisting of insect associated species. The type strain of Cr. bestiolae is TH3.2.59 (=CBS 10118=NRRL Y-27894), and the type strain of Cr. dejecticola is Litch 17 (=CBS 10117=NRRL Y-27898).     

The yeast community of sap fluxes of Costa Rican Maclura (Chlorophora) tinctoria and description of two new yeast species,Candida galis and Candida ortonii

We report on the yeast community associated with sap fluxes of Maclura tinctoria, family Moraceae, in the dry forest of the Area de Conservación Guanacaste, Costa Rica. Eleven samples yielded seven hitherto undescribed ascomycetous yeasts in the genera Candida and Myxozyma. We describe the two most abundant as new species. Candida galis utilizes very few carbon compounds limited to some alcohols and acids. Analysis of rDNA sequences suggests that it occupies a basal position with respect to the Pichia anomala clade, with no obvious sister species. Candida ortonii is also restricted in nutritional breadth, and growth is generally very slow. It is a sister species to Candida nemodendra. The type cultures are: C. galis, strain UWO(PS)00-159.2=CBS 8842; and C. ortonii, strain UWO(PS)00-159.3=CBS 8843.     

Candida alocasiicola sp. nov., Candida hainanensis sp. nov., Candida heveicola sp. nov. and Candida musiphila sp. nov., novel anamorphic, ascomycetous yeast species isolated from plants

In a taxonomic study on the ascomycetous yeasts isolated from plant materials collected in tropical forests in Yunnan and Hainan Provinces, southern China, four strains isolated from tree sap (YJ2E(T)) and flowers (YF9E(T), YWZH3C(T) and YYF2A(T)) were revealed to represent four undescribed yeast species. Molecular phylogenetic analysis based on the large subunit (26S) rRNA gene D1/D2 domain sequences showed that strain YJ2E(T) was located in a clade together with Candida haemulonii and C. pseudohaemulonii. Strain YF9E(T) was most closely related to C. azyma and strain YWZH3C(T) to C. sorbophila and C. spandovensis. Strain YYF2A(T) was clustered in a clade containing small-spored Metschnikowia species and related anamorphic Candida species. The new strains differed from their closely related described species by more than 10% mismatches in the D1/D2 domain. No sexual states were observed for the four strains on various sporulation media. The new species are therefore assigned to the genus Candida and described as Candida alocasiicola sp. nov. (type strain, YF9E(T) = AS 2.3484(T) = CBS 10702(T)), Candida hainanensis sp. nov. (type strain, YYF2A(T) = AS 2.3478(T) = CBS 10696(T)), Candida heveicola sp. nov. (type strain, YJ2E(T) = AS 2.3483(T) = CBS 10701(T)) and Candida musiphila sp. nov. (type strain, YWZH3C(T) = AS 2.3479(T) = CBS 10697(T)).     

Six new anamorphic ascomycetous yeasts near Candida tanzawaensis

Six new species of the yeast genus Candida are described from their unique nucleotide sequences in the D1/D2 domain of 26S rDNA. Five of these species form a clade with Candida tanzawaensis, and the sixth is basal to this group. The new species and their sources of isolation are the following: Candida ambrosiae (type strain NRRL YB-1316, CBS 8844), from insect frass, rotted wood and mushroom fruiting bodies; Candida canberraensis (type strain NRRL YB-2417, CBS 8846), from soil; Candida caryicola (type strain NRRL YB-1499, CBS 8847), from a pignut hickory tree; Candida prunicola (type strain NRRL YB-869, CBS 8848), from exuded gum of a black cherry tree; Candida pyralidae (type strain NRRL Y-27085, CBS 5035), from insect frass; Candida xylopsoci (type strain NRRL Y-27066, CBS 6037), from insect frass.