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This paper deals with the discovery of the teleomorph of a Fonsecaea-like pathogen causing chromoblastomycosis in India. A new genus, Ascosubramania, is proposed to accommodate it.

Metarhizium anisopliae var. anisopliae (Metschnikov) Sorokin 1883 to our knowledge has never been reported as an agent of human or animal mycosis. This fungus has great importance as an agent of biological control of different pests and mosquito larvae in Colombia. It has been isolated as the aetiological agent of keratomycosis for the first time from the eye of a Colombian male.

ARDRA of ribosomal genes confirmed that the hyphomycete Scytalidium hyalinum is identical to the coelomycete Nattrassia mangiferae (Hendersonula toruloidea, with arthroconidial synanamorph Scytalidium dimidiatum). S. hyalinum may be just a melanin-less cultural mutant of S. dimidiatum. This explains why the two species are regularly found in the same patient population as agents of human dermatomycosis. Two strains from plant sources were found to be identical to the human strains in ITS-RFLP patterns. RFLP of SSU and LSU was hampered by the frequent occurrence of introns. Profiles of secondary metabolites were studied using TLC, GC and GC/MS. Production of metabolites varies considerably with the strain, but two naphthoquinone compounds were nearly always present. Selected-ion monitoring (SIM) of these compounds enabled the specific recognition of the taxon.

Two atopic siblings presented with unilateral chronic scaly plantar lesions. Histology revealed the presence of fungi with unusual morphological aspects. Scopulariopsis brevicaulis and Phoma spp., respectively, grew on repeated cultures. Dermatophytes were absent. Such opportunistic fungal infections of the stratum corneum are extremely rare.

Non-dermatophytic fungi are increasingly being recognized as agents of onychomycosis. In 1990, three cases of chronic infection of the great toenail in adult female residents of Canada were attributed to Onychocola canadensis, a previously unknown hyphomycete. Three additional cases were suspicious but unconfirmed. This report documents seven new records, including six of toenail infection in elderly individuals and one case of glabrous skin infection. Three isolations from New Zealand represent the first report of O. canadensis outside Canada. Treatment with griseofulvin in one New Zealand hallux infection case was found to improve the appearance of the nail, but specimens were culture positive after 6 months. The development in culture of broad, brown, nodose, thick-walled hyphae suggested an affinity to the ascomycete genus Arachnomyces. Although mating experiments were attempted on several different media, ascocarps were produced in six mated pairs on sterilized rice grains or rice extract agar after 7-12 months incubation. Arachnomyces nodosetosus Sigler & Abbott sp. nov. is described and compared with Arachnomyces minimus Malloch & Cain, also rarely isolated from cutaneous specimens. The genus Arachnomyces is placed in the Gymnoascaceae (Onygenales).

The second known case of a skin infection caused by Botryomyces caespitosus is reported. This case has made it possible to describe the characteristics of this fungus in vivo and to establish it as another agent of phaeohyphomycosis.

Dactylaria gallopava and Scolecobasidium constrictum were reduced to varietal status under the new combination of Dactylaria constricta (Abbott) Dixon et Salkin var. gallopava (Cooke) Salkin & Dixon, and D. constricta (Abbott) Dixon et Salkin var. constricta, primarily on the basis of the morphologic similarity of their two-celled, dematiaceous, blastic conidia. To appraise this taxonomic change, we studied the antigenic relationship of D. gallopava to S. constrictum using the exoantigen procedure. Exoantigens were prepared from 20 isolates of D. gallopava, seven isolates of S. constrictum and two isolates of S colecobasidium tschawytschae and were tested against reference rabbit anti-D. gallopava and anti-S. constrictum antisera in the presence of their homologous antigens using the micro-immunodiffusion technique. All D. gallopava isolates produced two to three distinct, identical exoantigens. The seven isolates of S. constrictum also produced two to three distinct exoantigens. None of the seven isolates of S. constrictum was reactive against the D. gallopava reference system. Three of the 20 D. gallopava culture filtrate antigens produced one or two precipitin bands of nonidentity with the S. constrictum reference reagents. Both isolates of S. tschawytschae were nonreactive with the D. gallopava and S. constrictum reference reagents. In addition, D. gallopava differed from S. constrictum in the production of a reddish-brown diffusible pigment, growth up to 45 degrees C, and sensitivity to cycloheximide. Based on these physiologic differences and little or no antigenic relatedness between D. gallopava and S. constrictum, we conclude that these two species should be retained as separate entities rather than be considered as varieties of a single species.

Three cases of great toenail infection are described in which a slow-growing arthroconidial hyphomycete was isolated repeatedly and in pure culture. Direct microscopy revealed hyaline, round to barrel-shaped arthroconidia, hyaline hyphae of varying width, and broad thick-walled brownish hyphae. Three additional isolates were obtained from clinical specimens, for which the results of direct microscopy were unknown or negative. The fungus was resistant to cycloheximide, sensitive to common antifungal drugs by susceptibility tests in vitro and sensitive to benomyl. It was urease positive, hydrolysed casein and tyrosine but not xanthine or hypoxanthine, showed no specific nutritional requirements but grew better on carbohydrate-free media, assimilated 12 carbohydrates and potassium nitrate, and failed to perforate hair. The fungus is described as Onychocola canadensis Sigler gen. et sp. nov., and it is compared to Scytalidium lignicola, Scytalidium hyalinum and the Scytalidium synanamorph of Nattrassia mangiferae (Hendersonula toruloidea).

A hyphomycete isolated from a pale-grain eumycetoma in an indian male patient is described as a species of a new form-genus, Polycytella hominis. The fungus is characterized by elongate multiseptate conidia in which only the apical compartment becomes thick-walled and retains viable cytoplasm. The appearance of P. hominis in the host tissues is described and compared with other pale-grain eumycetomas.

Cladosporium trichoides Emmons has been treated by some mycologists as a synonym of Cladosporium bantianum (Sacc.) Borelli and has been transferred to the genus Xylohypha (Fr.) Mason. In the present study, a herbarium specimen of C. bantianum (Torula bantiana Sacc.) Borelli, prepared by Saccardo, was compared with a herbarium specimen and a living type culture of C. triochoides by light and scanning electron microscopy (SEM) and was found to be dissimilar. Herbarium specimens and living cultures of Xylohypha nigrescens, the type species of the genus Xylohypha, were also compared with those of C. trichoides and other pathogenic Cladosporium species. Fundamental differences were found between X. nigrescens and Cladosporium species, in colony morphology, manner of sporulation and conidial morphology. All Cladosporium isolates produced olive-black colonies regardless of environmental conditions, bore brown pigment on the walls of the vegetative hyphae as well as on the walls of the fruiting structures and produced branched chains of conidia either from well differentiated or poorly differentiated conidiophores, or directly from the hyphae. By SEM, conidia showed strong to moderately protruded hila, and the basal contour of the conidia was always truncated. On germination, hyphal tubes were produced randomly from the surface of the conidia. In contrast, X. nigrescens produced white colonies with or without brown centres, depending on the culture medium, bore pigment on the conidial walls and on conidiogenous cells but not on the vegetative hyphae and produced infrequently branched conidial chains, usually from intercalary conidiogenous cells which were globose to hat-shaped. Conidial hila were nonprotruding but, instead, were deeply concave and pore-like. The basal contour of the conidia was round and germ tubes were produced only from the pore-like hila. These results indicate that C. triochoides Emmons is different from C. bantianum (Sacc.) Borelli and that the reclassification of C. trichoides into the genus Xylohypha was not warranted.

Sarcinomyces phaeomuriformis is described as a new species in the genus Sarcinomyces Lindner. Currently, the taxon is known to occur only in Japan as a causal agent of phaeohyphomycosis. The colonies are initially yeast-like, which on aging become dry, granular, heaped, friable and black. The initial growth consists of single cells which form multiple broad-based buds and by a successive budding process produce chains of blastoconidia. In its blastic conidiogenesis, S. phaeomuriformis resembles Phaeococcomyces catenatus. However, mature colonies consist of thick-walled, pale to dark brown muriform cells which develop broad-based buds. The buds, after separating from their parent cells, either bud or enlarge and divide internally by septations laid down in different planes to become muriform. Conidiogenesis that gives rise to multiple, broad-based blastic and thallic-sarcinic conidia characterizes S. phaeomuriformis.

Culture filtrate and cellular antigens prepared from 14 agents which cause black grain eumycetoma were compared by double diffusion and immunoelectrophoresis. The fungal agents studied included five isolates of Madurella grisea, two of Madurella mycetomatis and a single isolate each of Pyrenochaeta mackinnonii, Pyrenochaeta romeroi, Chaetosphaeronema (Pseudochaetosphaeronema) larense, Plenodomus avramii, Phoma/Phyllosticta, Aureobasidium (Exophiala) mansonii and Leptosphaeria senegalensis. Cross-comparisons between all paired combinations of antigens and rabbit antisera raised against each antigen, before and after absorption with heterologous antigens, were expressed as percentage homologies. Cross-reactivity was marked (up to 90%) within the M. grisea group and between M. grisea and P. mackinnonii, but not with P. romeroi. The results suggest that the representatives of the M. grisea group tested were similar or identical to P. mackinnonii. Little antigenic similarity was observed between M. grisea and M. mycetomatis. The remaining antigens and antisera reacted most strongly with their homologous counterparts, except for L. senegalensis which had antigens in common with M. grisea (0-55% homology) and P. mackinnonii (70% homology). Analysis of the antigenic patterns derived from five of six unidentified isolates from patients with black grain eumycetoma showed marked similarity to M. grisea and P. mackinnonii.