The Genus Uncinocarpus (Onygenaceae) and Its Synonym
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1624 The genus Uncinocarpus (Onygenaceae) and its synonym Brunneospora: new concepts, combinations and connections to anamorphs in Chrysosporium, and further evidence of relationship with Coccidioides immitis1 Lynne Sigler, Arlene L. Flis, and J.W. Carmichael Abstract: The genus Uncinocarpus (Onygenales, Onygenaceae) is emended to include keratinophilic fungi with discrete, globose gymnothecial ascomata without differentiated ascomatal hyphae and bearing uncinate, helical, or no appendages; oblate, punctate ascospores sometimes with irregular reticulations; bulbous initials, and Malbranchea or Chrysosporium anamorphs. The new combination Uncinocarpus orissi is proposed for Pseudoarachniotus orissi; Gymnoascus arxii is shown to be a synonym. New records show that the fungus has a wide distribution from North America, Europe, Asia, and the Middle East. The teleomorph is formed under laboratory conditions by mating representative isolates. The anamorph has been described under the names Chrysosporium zonatum and Chrysosporium gourii. Chrysosporium queenslandicum is morphologically similar. Its teleomorph Apinisia queenslandica is transferred also to the genus Uncinocarpus as Uncinocarpus queenslandicus. Brunneospora reticulata, the type species of the genus Brunneospora, is a synonym. Orromyces spiralis appears to be another name applied to this fungus. Development of helical coils in an isolate of Coccidioides immitis provides further evidence of a possible relationship between this dimorphic human pathogen and this group of ascomycetes. Key words: Uncinocarpus, Onygenales, systematics, keratinophiles, human pathogen. Résumé : Les auteurs amendent le genre Uncinocarpus (Onygénales, Onygénacées) pour y inclure des champignons kératinophiles comportant de petits ascomata gymnothèques globulaires sans hyphes ascomatales différenciées, et portant ou non des appendices uncinés ou hélice, des ascospores ponctuées, aplaties aux pôles, quelquefois avec des réticulations, des (cellules) initiales bulbeuses, et des anamorphes de types Malbranchea ou Chrysosporium. On propose la nouvelle combinaison Uncinocarpus orissi pour remplacer le Pseudoarachniotus orissi; on montre que le Gymnoascus arxii est un synonyme. De nouvelles mentions montrent que ce champignon est largement répandu en Amérique du Nord, en Europe, en Asie et au Moyen-Orient. On obtient la formation du téléomorphe au laboratoire, en croisant des isolats représentatifs. L’anamorphe a été décrit sous les noms de Chrysosporium zonatum et de Chrysoporium gourii. Le Chrysoporium queenslandicum est morphologiquement similaire. On transfère son téléomorphe Apinisia queenslandica également au genre Uncinocarpus devenant l’Uncinocarpus queenslandicus. Le Brunneospora reticulata, espèce type du genre Brunneospora, est un synonyme. Il semble que l’Orromyces spiralis soit un autre nom appliqué à ce champignon. Le développement d’un boudin en hélice chez un isolat du Coccidioides immitis constitue un autre élément de preuve de la relation possible entre ce pathogène humain dimorphe et ce groupe d’ascomycètes. Mots clés : Uncinocarpus, Onygénales, systématique, kératinophyles, pathogène humain. [Traduit par la Rédaction] Received December 18, 1997. L. Sigler2 and A.L. Flis. University of Alberta Microfungus Collection and Herbarium, Devonian Botanic Garden, Edmonton, AB T6G 2E1, Canada. J.W. Carmichael. S 31, C 4, RR 1, Fanny Bay, BC V0R 1W0, Canada. 1 This paper is dedicated to Dr. Stanley J. Hughes, a collegial and prodigious worker internationally acclaimed as a brilliant systematist whose theories on classification of conidial fungi have influenced scores of other workers. A model to us all, Stan has followed an exem- plary career of 31 years of service and research in Canada and the United Kingdom with several years of dedicated research in retirement. We honor and congratulate him on his 80th birthday. 2 Author to whom all correspondence should be addressed. e-mail: [email protected] Can. J. Bot. 76: 1624–1636 (1998) © 1998 NRC Canada Sigler et al. 1625 Introduction The purpose of this study was to evaluate the relationship among and between these taxa, to define species concepts, A recent review of the Onygenales (Scott et al. 1993) and to redescribe cultural features We used mating tests to presented a key to 11 genera in which the ascomata possess confirm relationships among our Chrysosporium isolates and uncinate, curved, or helical appendages. The genera Uncino- the ex-type strain of C. zonatum and between them and ex- carpus, Brunneospora, and Apinisia were distinguished in type strains of G. arxii and P. orissi. Neither Gymnoascus nor part by ascospore shape: oblate for Uncinocarpus, ellipsoidal Pseudoarachniotus is suitable for disposition of the teleo- for Brunneospora, and globose for Apinisia. Sigler and Car- morph of C. zonatum. Therefore, it is redisposed here in Unci- michael (1976) described the genus Uncinocarpus for Unci- nocarpus and the genus is emended. nocarpus reesii Sigler & G.F. Orr, a soil fungus having reddish brown, oblate, smooth ascospores that were later Materials and methods shown by scanning electron microscopy (SEM) to be orna- mented with small puncta (pits or depressions) (Currah 1985). Studied strains were on deposit at the University of Alberta Micro- Other distinguishing features of U. reesii included heterothal- fungus Collection and Herbarium (UAMH) and included 15 strains lic compatibility, bulbous initials, and discrete globose gym- preliminarily identified as Chrysosporium sp. IX and ex-type strains of C. zonatum (UAMH 6617), Chrysosporium gourii (UAMH 4436), nothecial ascomata composed of a loose network of uncinate P. or iss i (UAMH 6950), G. arxii (UAMH 6611), A. queenslandica appendages. The species also produced a distinctive Mal- (UAMH 4319), and B. reticulata (UAMH 5704). Type material of the branchea anamorph, which had first attracted the attention of latter three species was obtained on loan. mycologists because of morphological and habitat similarities Repeated attempts were necessary to mate available strains with the dimorphic human pathogenic fungus Coccidioides because of low fertility among tested strains. Changes were made to immitis Stiles (Sigler and Carmichael 1976). Recent molecu- growth conditions including medium and temperature and to the lar studies have confirmed a close relationship between these methods of inoculation, using methods described by Sigler (1996). species (Pan et al. 1994; Bowman et al. 1996), but no meiotic Initial experiments used autoclaved garden soil plus autoclaved stage is known for the latter. human hair or horsehair and incubation at room temperature (22– Guarro et al. (1987) introduced the monotypic genus Brun- 25ЊC). Strains were paired in all possible combinations, including self–self pairings. Subsequent experiments used soil extract agar, neospora Guarro & Punsola for a keratinophilic fungus iso- both without and with glucose (recipe in Sigler 1996 but without lated by hair bait of soil samples in Spain. The genus was yeast extract), oatmeal salts agar, or Takashio agar (recipes in Kane et distinguished by globose gymnothecial ascomata with helical al. 1997). All agar media were supplemented with sterile human hair appendages, reddish brown, reticulate, ellipsoidal asco- or horsehair. The latter two media and incubation at 28–30ЊC were spores, and a Chrysosporium anamorph. Brunneospora retic- found to be optimal. Plates were held for 3–6 months before being ulata, the type species, was represented by two collections, of discarded as negative. The first experiment, which included nine which only the type was obtained in axenic culture and it con- strains (2041, 2538, , 3728, 4044, 4426, 4427, 6499, and 6500), sisted mainly of the anamorph. Orromyces spiralis B. Sur & yielded fertile crosses among three pairings (6499 × 6500, 4426 × 4427, and 4427 × 6500). Seven single ascospore isolates were G.R. Ghosh (Ghosh and Sur 1985), known only from the × original description, appears to be similar. obtained from the cross of 4427 6500 and checked for fertility on their own and in backcrossings with the parent strains. Two single Brunneospora was distinguished from the genus Apinisia ascospore isolates (6635 and 9097) were designated as plus mating La Touche (1968) by ascospore shape. However, a second strains and two (6636 and 9098) as minus mating strains and were species, Apinisia queenslandica Apinis & R.G. Rees (1976) used in subsequent mating experiments. Each was nonfertile in self– differs from the type species Apinisia graminicola La Touche self pairings but fertile when backcrossed with one of the parent in ascospore shape and substrate preferences. Previous strains. workers (Currah 1985; Guarro et al. 1991) have suggested For SEM, ascospores were obtained from dried type material and that A. queenslandica be redisposed. There appear to be no fresh cultural material. Ascospores were affixed directly onto Avery records of B. reticulata or A. queenslandica other than from label glue coated onto stubs or onto glue that had been dissolved in the original descriptions, but the anamorph Chrysosporium chloroform. A coating of gold or gold–palladium was applied with an queenslandicum Apinis & R.G. Rees is occasionally listed in Edwards sputter coater (S150B) and specimens were examined and photographed with either a Cambridge S-250 or an Hitachi S-2500 surveys of keratinophilic fungi. SEM. Our interest in the preceding taxa arose from difficulties in Growth studies were conducted