Description of Hymenobacter arizonensis sp. nov. from the southwestern arid lands of the United States of America.

Strain OR362-8(T) was isolated from a biological soil crust sample collected from the southwestern arid lands of the United States of America, using BG11-PGY medium. Cells of OR362-8(T) were found to be rod shaped; occur singly, as pairs and in groups; non-motile; positive for catalase, oxidase, phosphatase and gelatinase; hydrolyze starch; contain iso-C(15:0), anteiso-C(15:0), iso-C(15:1)G, C(16:1ω5c) and summed feature 3 (C(16:1(ω7c))/iso-C(15:0) 2OH as defined by the MIDI system) as the major fatty acids; and MK-7 as the sole respiratory quinone. A BLAST sequence similarity search using 16S rRNA gene sequence of OR362-8(T) identified Hymenobacter as the nearest genus with a similarity of 90.

Description of Patulibacter americanus sp. nov., isolated from biological soil crusts, emended description of the genus Patulibacter Takahashi et al. 2006 and proposal of Solirubrobacterales ord. nov. and Thermoleophilales ord. nov.

Two bacterial strains, CP153-3 and CP177-2T, were isolated from biological soil crusts on the Colorado Plateau, USA, and assigned to the genus Patulibacter, according to 16S rRNA gene sequence analysis and phenotypic characteristics. The strains were Gram-positive, aerobic and psychrotolerant and showed positive catalase and negative oxidase reactions. Cells were motile in young cultures, motility consisting of subtle jerking motions, but no flagella could be detected.

Modestobacter versicolor sp. nov., an actinobacterium from biological soil crusts that produces melanins under oligotrophy, with emended descriptions of the genus Modestobacter and Modestobacter multiseptatus Mevs et al. 2000.

A novel isolate, CP153-2(T), was obtained from topsoil biological crusts in the Colorado Plateau (USA). Colonies were black in colour due to melanin-like pigments when grown on oligotrophic medium, but not when grown on copiotrophic medium. Induction of melanogenesis was independent of growth phase or illumination conditions, including exposure to UVB and UVA radiation, but exposure to UVB could enhance total pigment production and growth under low nitrogen prevented its synthesis.

Exophiala crusticola anam. nov. (affinity Herpotrichiellaceae), a novel black yeast from biological soil crusts in the Western United States.

A novel black yeast-like fungus, Exophiala crusticola, is described based on two closely related isolates from biological soil crust (BSC) samples collected on the Colorado Plateau (Utah) and in the Great Basin desert (Oregon), USA. Their morphology places them in the anamorphic genus Exophiala, having affinities to the family Herpotrichiellaceae (Ascomycota). Phylogenetic analysis of their D1/D2 large subunit nuclear ribosomal RNA (LSU nrRNA) gene sequences suggests that they represent a distinct species.

Belnapia moabensis gen. nov., sp. nov., an alphaproteobacterium from biological soil crusts in the Colorado Plateau, USA.

Strain CP2CT was isolated from biological soil crusts in the Colorado Plateau, USA. The isolate was aerobic, facultatively fermentative, Gram-negative, non-motile and red-pigmented (due to the presence of carotenoids), but did not contain bacteriochlorophyll a. The strain tested positive for catalase, oxidase and urease and was negative for lysine and ornithine decarboxylases and arginine dihydrolase.

Dyadobacter crusticola sp. nov., from biological soil crusts in the Colorado Plateau, USA, and an emended description of the genus Dyadobacter Chelius and Triplett 2000.

Bacterial strain CP183-8(T) was isolated from biological soil crusts collected in the Colorado Plateau, USA. Cells of this strain were aerobic, non-motile, Gram-negative, psychrotolerant and formed beaded chains in the stationary growth phase. They contained C(16 : 1)omega5c and C(16 : 1)omega7c as major fatty acids.

Kocuria polaris sp. nov., an orange-pigmented psychrophilic bacterium isolated from an Antarctic cyanobacterial mat sample.

Strain CMS 76orT, an orange-pigmented bacterium, was isolated from a cyanobacterial mat sample from a pond located in McMurdo Dry Valley, Antarctica. On the basis of chemotaxonomic and phylogenetic properties, strain CMS 76orT was identified as a member of the genus Kocuria. It exhibited a 16S rDNA similarity of 99.