- Email: [email protected]
Mycological Research News1
mycological research 113 (2009) 275–278
journal homepage: www.elsevier.com/locate/mycres
Mycological Research News1 In this issue Systematics and evolution in Torrubiella (pp. 279–289). Activation tagging of Antrodia cinnamomea (pp. 290–297). Genetic diversity in Phytophthora nemorosa and P. pseudosyringae (pp. 298–307). Species delimitation in Hyaloperonospora (pp. 308– 325). Genetic variation and relationships in Laetiporus sulphureus s. lat. (pp. 326–336). Botryosphaeriaceae from Eucalyptus gomphocephala woodland (pp. 337–353). A polyketide synthase gene from Solorina crocea (pp. 354–363). Electrostatic attraction of conidia of Oidium lycopersici (pp. 364–372). Koralionastetales, a new order of marine Ascomycota (pp. 373–380). Laccases in Pleurotus species with different pathogenic behaviour (pp. 381–387). A non-lethal Candida albicans mutant with protective properties against wild-type strains (pp. 388–390). Didymella pisi sp. nov., the teleomorph of Ascochyta pisi (pp. 391–400).
Palaeomycology: do we consider extinct lineages in the evaluation of fossil fungi? In the News section of the April issue of Mycological Research, Thorn et al. (2008) question our finding of a Cretaceous carnivorous fungus that is not assignable to modern representatives (Schmidt et al. 2007). However, while criticizing our interpretation of the fossil, they only explain what modern carnivorous fungi of the genus Dactylellina (Orbiliaceae, Ascomycota) look like. The differences of the fossil to modern taxa were already mentioned in our paper and are, on its own, insufficient to evaluate a 100 Myr old fossil. It is our intent not only to respond to their note, but also to encourage discussion on palaeomycology in general. The study of fossils is often considered to be less important when tracing the evolutionary history of fungi. Compared to animals and plants, well-preserved and well-determinable fungi are rare in the fossil record. Therefore, molecular phylogenies are accepted as more convincing. However, despite great advances in molecular approaches, the study of fossils provides insights into the evolutionary history that would not be possible using modern taxa alone. Molecular studies provide estimates of the actual phylogeny, which only wellpreserved and well-dated fossils can prove and calibrate.
Furthermore, and this is probably much more important, the study of modern taxa alone cannot uncover extinct lineages. Every modern species has an ancestor in Earth’s history, but, by far, not every species had a descendant. But in contrast to palaeozoology and palaeobotany, the occurrence of extinct taxa seems not to be allowed for fungi; indeed, the structures of fungal fossils are mostly interpreted only with reference to modern taxa. Palaeobotanists and palaeozoologists already found that it is more appropriate to investigate and to evaluate the functional morphology of a fossil before comparing it to extant forms. This avoids possible misinterpretations based only on comparisons to modern species. Thorn et al.’s comment reflects the problem of different approaches in different research fields. The discovered amber-preserved fungus possessed hyphal rings and formed blastospores that initiated a yeast stage. Thorn and his co-authors question the existence of such a fungus because no predatory fungus possessing regular yeast stages and single-celled trapping rings is known from modern ecosystems. Would they too, explain to a vertebrate palaeontologist who just excavated an articulated dinosaur skeleton, that these bones must not belong to a single specimen because modern birds look different? Further, Thorn et al.’s doubt is based solely on the few images of our preliminary report in the Brevia section of Science (Schmidt et al. 2007), not on the extensive description of this fossil that we provided elsewhere (Schmidt et al. 2008). A Mesozoic fungus must not necessarily be assignable to a modern group. When working exclusively with molecular phylogenies of extant taxa, that representatives of extinct lineages in the Earth’s history may have had other features is rarely considered. In criticizing our interpretation, Thorn et al. only refer to a single group of modern carnivorous fungi with rings as trapping devices that show differences to the rings of the fossil. Modern predatory fungi, however, are not a monophyletic but an ecological group with different traps, such as adhesive hyphae, sessile and stalked adhesive knobs, adhesive networks, or constricting and non-constricting rings. It is therefore not improbable that in the Earth’s history there were also other groups of fungi with analogous trapping devices occupying the same ecological niche in soil ecosystems. Furthermore, Thorn et al. suggest that the fossil trapping rings would not have functioned because: (1) they are also found
1 Mycological Research News is compiled by the Associate Senior Editor, David L. Hawksworth, Departamento de Biologı´a Vegetal II, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramo´n y Cajal, Ciudad Universitaria, ES-28040 Madrid, Spain (e-mail: [email protected]), to whom items for inclusion should be sent. Unsigned items are by the Associate Senior Editor.
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detached from the mycelium: (2) sticky rings could not work at all: and (3) the illustrated fossil nematodes are too slender to become trapped. These remarks also do not stand up to critical examination. In the specimens preserved in amber, it is very likely that the rings did not detach by intensive struggling of trapped nematodes, but when being overflowed by the resin. Sticky hyphal loops are widespread in carnivorous fungi trapping with adhesive networks (e.g. Dove 1987: figs 22–24). In adhesive traps, the actual diameter of loops and nematodes is less important. Furthermore, the maximum diameter of nematodes has a wide width range depending on the species and the age of the animals. We found four taxa of nematodes of different size in amber piece ARC 115. For the Science Online Material, we decided to select images of the best-preserved individual and of that nematode being very closely located to a trapping ring. Finally, Thorn et al. even question palaeomycology in general, and state that the morphology of fossil fungi would remain suggestive but inconclusive for identification. Hereby, they deny the great progress made in palaeomycology, especially in the last two decades. Increasing interest in this field has led to a plethora of newly discovered fossil fungi preserved in amber, chert, and sediments, which provide relevant diagnostic features and demonstrate that it is highly informative to examine fossils as well as to study molecular phylogenies (e.g. Taylor et al. 2004; Taylor & Krings 2005; Fleischmann et al. 2007; Do¨rfelt & Schmidt 2007). Amazing evolutionary stasis is evident for some groups in the Phanerozoic (e.g. chytrids), but also archaic taxa occur amongst them (e.g. Schmidt 2006). Organisms with intermediate features did not just occur during branching of the respective major groups in deep time, but sometimes persisted for millions of years. Even in the piece of amber which encloses the carnivorous fungus, a fossil was preserved that sheds new light on the early structure of feathers (Perrichot et al. 2008), although feathers of more advanced development already existed at least 50 Myr before that particular resin piece solidified. We thank Kerstin Schmidt (Jena) for discussion. Do¨rfelt H, Schmidt AR, 2007. A conifer seedling with two herbicolous fungi from the Baltic amber forest. Botanical Journal of the Linnean Society 155: 449–456. Dove A, 1987. Ra¨uberische Pilze. Brehm-Bu¨cherei, Wittenberg Fleischmann A, Krings M, Mayr H, Agerer R, 2007. Structurally preserved polypores from the Neogene of North Africa: Ganodermites libycus gen. et sp. nov. (Polyporales, Ganodermataceae). Review of Palaeobotany and Palynology 145: 159–172. Perrichot V, Marion L, Ne´raudeau D, Vullo R, Tafforeau P, 2008. The early evolution of feathers: fossil evidence from Cretaceous amber of France. Proceedings of the Royal Society B, Biological Sciences 275: 1197–1202. Schmidt AR, 2006. Microorganisms and microcoenoses of Cretaceous forests – new insights from amber. In: Barrett PM, Evans SE (eds), Ninth International Symposium on Mesozoic Terrestrial Ecosystems and Biota. Natural History Museum, London, pp. 110–113. Schmidt AR, Do¨rfelt H, Perrichot V, 2007. Carnivorous fungi from Cretaceous amber. Science 318: 1743. Schmidt AR, Do¨rfelt H, Perrichot V, 2008. Palaeoanellus dimorphus gen. et sp. nov. (Deuteromycotina): a Cretaceous predatory fungus. American Journal of Botany 95: 1328–1334. Taylor TN, Krings M, 2005. Fossil microorganisms and land plants: associations and interactions. Symbiosis 40: 119–135.
D. L. Hawksworth
Taylor TN, Klavins SD, Krings M, Taylor EL, Kerp H, Hass H, 2004. Fungi from the Rhynie chert: a view from the dark side. Transactions of the Royal Society Edinburgh, Earth Sciences 94: 457–473. Thorn RG, Scholler M, Gams W, 2008. Have carnivorous fungi been found in Cretaceous amber? Mycological Research 112: 611–612.
Alexander R. Schmidta, Heinrich Do¨rfeltb, Vincent Perrichotc a Georg-August-Universita¨t Go¨ttingen, Courant Research Centre Geobiology, Goldschmidtstraße 3, D-37077 Go¨ttingen, Germany b Martin-Luther-Universita¨t Halle, Institut fu¨r Geobotanik und Botanischer Garten, Neuwerk 21, D-06108 Halle/Saale, Germany c Paleontological Institute, University of Kansas, Lindley Hall, 1475 Jayhawk Blvd, Lawrence, Kansas KA 66045, USA E-mail: [email protected]
We accept evidence, but not conjecture, regarding fossil fungi We welcome the comments of Schmidt et al. (2009, above) regarding the value of fossil evidence, including evidence of fossil fungi, in providing clues to the past and to the evolution of extant organisms. However, we wish to be very clear that we do not reject fossil evidence, nor do we reject the existence of extinct lineages or the idea that fossil fungi could have had combinations of characters not seen in present-day taxa. Unfortunately, we have to reiterate that the papers by Schmidt et al. (2007, 2008) did not present any such evidence. None of the photographic illustrations in either of their papers provides evidence that: (1) the rings shown caught nematodes: or (2) that the organism producing the rings and the one producing the yeast-like blastospores were connected as one fungus. These conjectures were only supported by a drawing that made the connections for which no photographic evidence was supplied, and the specimens on which their reports were based in the Paris Museum were not then available for loan to us so that their conjecture could not be corroborated. In our opinion, what Schmidt et al. (2008) described as Palaeoanellus dimorphus and purported to be a Cretaceous predatory fungus is, in fact, an amalgam of unconnected, unrelated parts, neither of which was nematophagous. In addition, we wish to draw the attention to what Do¨rfelt & Schmidt (2007) described as the new Gonatobotryum piceae, also in amber, which can clearly be recognized as two species of Chloridium as described by Gams & Holubova´Jechova´ (1976). Our comments are in no way a criticism of other fine, careful work in paleomycology that both we (Thorn et al. 2008) and they (Schmidt et al. 2009, above) have cited. Do¨rfelt H, Schmidt AR, 2007. A conifer seedling with two herbicolous fungi from the Baltic amber forest. Botanical Journal of the Linnean Society 155: 449–456. Gams W, Holubova´-Jechova´ V, 1976. Chloridium and some other dematiaceous hyphomycetes growing on decaying wood. Studies in Mycology 13: 1–99. Schmidt AR, Do¨rfelt H, Perrichot V, 2007. Carnivorous fungi from Cretaceous amber. Science 318: 1743. Schmidt AR, Do¨rfelt H, Perrichot V, 2008. Palaeoanellus dimorphus gen. et sp. nov. (Deuteromycotina): a Cretaceous predatory fungus. American Journal of Botany 95: 1328–1334.
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Schmidt AR, Do¨rfelt H, Perrichot V, 2009. Palaeomycology: do we consider extinct lineages in the evaluation of fossil fungi? Mycological Research 113: 275–276. Thorn RG, Scholler M, Gams W, 2008. Have carnivorous fungi been found in Cretaceous amber? Mycological Research 112: 611–612.
reclassified as Lichtheimia dubia by Vuillemin (1904), and so Lichtheimia is the name to be taken up. The following nomenclatural changes are therefore necessary:
R. Greg Thorna, Markus Schollerb, Walter Gamsc Department of Biology, University of Western Ontario, 1151 Richmond Street North London, Ontario, N6A 5B7, Canada b Staatliches Museum fu¨r Naturkunde, Erbprinzenstr. 13, D-76133 Karlsruhe, Germany c Molenweg 15, 3743 CK Baarn, The Netherlands E-mail: [email protected]
Coloniae 37–42 C celeriter, 55 C tarde crescentes. Stolones et rhizoidea saepe praesentes. Sporangiophora erecta vel partim arcuata, partim racemosa, sporangia saepe terminalia ferentia. Sporangia sphaerica vel subpyriformia, apophysata. Septum nonnumquam sub sporangio praesens. Columellae sphaericae vel hemisphaericae. Sporangiosporae sphaericae vel ellipsoideae. Cellulae giganteae frequentes, magnitudine variabiles. Suspensores magnitudine fere aequales, appendicibus carentes. Zygosporae crassitunicatae, nudae, fuscae, rasiles, sphaericae vel doliiformes, nonnumquam circulis aequatorialibus praeditae.
a
Mycocladus vs. Lichtheimia: a correction (Lichtheimiaceae fam. nov., Mucorales, Mucoromycotina) Hoffmann et al. (2007), in a revision of Absidia s. lat., reintroduced the generic name Mycocladus Beauve´rie 1900 for a closely related group of thermotolerant species (temperature optimum 33–37 C) with often terminal sporangia, and zygospore suspensors lacking appendages. Upon closer inspection, this genus cannot be used for these fungi because its type, M. verticillatus, was described as lacking terminal sporangia, having appendages on the columella and subsporangial septa, and growing optimally at 30 C and not above 40 C, thus characteristic of Absidia s.str. The main morphological parameters of the asexual structures of M. verticillatus come as close as possible to those of Absidia caerulea (unnecessarily orthographically ‘corrected’ to A. coerulea in some recent literature) or A. glauca. But the zygospores were described as lacking suspensors and covered with scales, a feature unknown in either group of species and causing some confusion. The scaled exospore may be taken as the tubercular exospore of a Mucor-like zygospore as developed by the mycotrophic Lentamyces parricida (Hoffmann & Voigt 2009). This assumption is supported by Beauve´rie’s (1900) observation of parasitic interactions with other moulds. In all likelihood, Beauve´rie observed a co-culture between a mesophilic Absidia and a mycotrophic Lentamyces. Consequently, the type species of Mycocladus is not congeneric with the thermotolerant Absidia-like species and the corresponding family name Mycocladaceae (orthographically wrongly given as Mycocladiaceae in the original publication) cannot be retained in the sense intended because it was based on a taxonomically different type. Looking for alternative solutions, the next candidate genera to consider to accommodate the thermotolerant group are Lichtheimia (Vuillemin 1903: 126) and Pseudoabsidia (Bainier 1903: 155; as ‘Pseudo-Absidia’), both published in the same issue of the Bulletin de la Socie´te´ Mycologique de France. Lichtheimia was typified by L. corymbifera, named in honour of the Swiss mycologist Lichtheim. Bainier (op. cit.) was the first to described rough-walled zygospores with equatorial ridges for Pseudoabsidia vulgaris, based on Absidia dubia Bainier 1882. The erroneous choice of the epithet was corrected in the same year by Sydow (1903), who made the combination Pseudoabsidia dubia. That rather confused species was already
Lichtheimiaceae K. Hoffm., G. Walther & K. Voigt, fam. nov. MycoBank no.: MB508680
Typus: Lichtheimia Vuill. 1903. Lichtheimia Vuill. Bull. Soc. mycol. Fr. 19: 126 (1903). Colonies rapidly-growing mainly at optimum temperatures between 37 C and 42 C, predominantly thermotolerant until max. 55 C, non-phototrophic. Hyphae often forming stolons and rhizoids and terminal sporangia. Hyphae and sporangiophores unseptated, unbranched, rarely sporangiophores with subsporangial septum and subsporangial whorls forming terminal sporangia. Sporangiophores erect or slightly bent. Sporangia multi-spored, spherical or subpiriform, apophysate. Collumellae spherical or hemispherical, occasionally conical. Sporangiospores spherical or ellipsoidal. Giant cells abundant or occasionally developed, irregularily shaped (pleomorphic) with finger-like projections. Zygospores developing from opposed gametangia, globose to oval, thick-walled, naked, smooth and less ornamented epispore, dark brown, suspensors more equal less inequal in size, non-appendaged, occasionally developing equatorial rings surrounding the zygospores. Type: Lichtheimia corymbifera (Cohn) Vuill. 1903. Lichtheimia corymbifera (Cohn) Vuill., Bull. Soc. mycol. Fr. 19: 126 (1903). MycoBank no.: MB416447 Basionym: Mucor corymbifer Cohn, in Lichtheim, Z. Klin. Med. 7: 149 (1884). Synonym: Mycocladus corymbifer (Cohn) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 95 (1979); as ‘corymbifera’. Lichtheimia ramosa (Zopf) Vuill., Bull. Soc. mycol. Fr. 19: 126 (1903). MycoBank no.: MB416448 Basionym: Mucor ramosus Zopf, in Schenk, Handb. Botanik 4: 587 (1890). Synonyms: Mucor ramosus Zopf, in Lindt, Arch. Exp. Path. Pharmacol. 21: 269 (1886); nom. illegit. (Art. 53). Mycocladus ramosus (Zopf) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 95 (1979). Lichtheimia blakesleeana (Lendn.) K. Hoffm., G. Walther & K. Voigt, comb. nov. MycoBank no.: MB512831 Basionym: Absidia blakesleeana Lendn., Bull. Soc. Bot. Gene`ve, Se´r. 2, 15: 149 (1924).
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Synonym: Mycocladus blakesleeanus (Lendn.) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 94 (1979). Lichtheimia hyalospora (Saito) K. Hoffm., G. Walther & K. Voigt, comb. nov. MycoBank no.: MB512830 Basionym: Tieghemella hyalospora Saito, Zentbl. Bakt. ParasitKde, Abt. 2, 17: 103 (1906). Synonyms: Absidia hyalospora (Saito) Lendn., Mat. Fl. Cryptog. Suisse 3(1): 142 (1908). Mycocladus hyalosporus (Saito) J.H. Mirza, in Mirza et al., Pakistan (Faisalabad): 97 (1979). For additional synonyms of these species see Hoffmann et al. (2007). We wish to express our gratitude to Walter Gams (Baarn, The Netherlands) for critically reading the manuscript, and Gerald L. Benny (University of Florida, Gainsville, USA) and Paul M. Kirk (CABI Biosciences-Europe, Egham, UK) for valuable advice on taxonomic interpretations. We thank Sigrid Neuhauser (University of Innsbruck, Austria) for accessing French literature databases. This work was supported by a grant of the Deutsche Forschungsgemeinschaft to KV (VO772/9-1). Bainier G, 1903. Sur quelques espe`ces de Mucorine´es nouvelles ou peu connues. Bulletin de la Socie´te´ mycologique de France 19: 153–172. Beauve´rie J, 1900. Mycocladus verticillatus. Annales de l’Universite´ de Lyon 3: 162–180. Hoffmann K, Discher S, Voigt K, 2007. Revision of the genus Absidia (Mucorales, Zygomycetes): based on physiological, phylogenetic and morphological characters: Thermotolerant Absidia spp. form a coherent group, the Mycocladiaceae fam. nov. Mycological Research 111: 1169–1183. Hoffmann K, Voigt K, 2009. Absidia parricida plays a dominant role in biotrophic fusion parasitism among mucoralean fungi (Zygomycetes): Lentamyces, a new genus for A. parricida and A. zychae. Plant Biology, doi: 10.1111/j.1438–8677.2008.00145.x. Sydow H, 1903. Referate und kritische Besprechungen. Annales Mycologici 1: 371. Vuillemin P, 1903. Le genre Tieghemella et la se´rie de Absidie´es. Bulletin de la Socie´te´ mycologique de France 19: 119–127. Vuillemin P, 1904. Le Lichtheimia ramosa (Mucor ramosus Lindt), champignon pathoge`ne, distinct du L. corymbifera. Archives de Parasitolologie 8: 562–572.
Kerstin Hoffmanna, Grit Waltherb, Kerstin Voigta a Fungal Reference Centre, Institute of Microbiology, University of Jena, Neugasse 24 D-07743 Jena, Germany b CBS Fungal Biodiversity Centre, P.O. Box 85167, 3508 AD Utrecht, The Netherlands E-mail: [email protected]
Fungal compounds can detrimentally affect diagnoses and phylogenetic analyses As molecular methods assume an increasing role in the identification of fungi and also in phylogenetic analyses, it is essential that users are aware of possible caveats that need to be considered when using them. In fungi that produce bioactive extrolites, especially compounds that are established mutagens, such as aflatoxins, Paterson et al. (2008) point out that these have the potential to inhibit DNA stabilizing enzymes. Further, in the case of examination for genes involved in mycotoxin production, they
stress that this problem could lead to incorrect conclusions as to the safety of particular isolates. In addition, as the culture medium can affect compound expression, growing fungi in media with inhibitors and mutagens could alter the DNA. While many fungi survive the mycotoxin levels they produce in nature, these may accumulate to such high concentrations in broths and agars that they can be detrimental. If different media are employed when growing fungi for DNA extraction, this could affect the comparability of phylogenetic results. In addition, even if the same medium is employed, each taxon, or even strain, may produce different bioactive extrolites qualitatively and/or quanitatively, hence potentially affecting results. The problems has been recognized for over a decade, especially by mycologists working with mycotoxins, and Paterson et al. (2008) provide many examples from the literature and draw attention to cases where the findings have been compromised. In order to avoid such potential problems in the case of PCR inhibition, it is suggested that internal amplification controls (IACs) are adopted, and even made mandatory for mycotoxin gene detection. The IACs proposed are sequences that will provide a PCR product using the same primers being employed but which will not coincide with the product from the target gene. However, for DNA mutation and stabilisation, the answer lies in ensuring extrolites are not produced in culture. This paper brings to the fore issues that merit the serious attention of all who use cultured fungi in either molecular diagnostics or phylogenetic systematics. Paterson RRM, Sariah M, Lima N, Zainal Abidin MA, Santos C, 2008. Mutagenic and inhibitory compounds produced by fungi affect detrimentally diagnosis and phylogenetic analysis. Current Bioactive Compounds 4: 245–257.
New scientific names in this issue Aplosporella yalgorensis sp. nov. Conoideocrella gen. nov. C. luteorostrata comb. nov. (syn. Torrubiella luteorostrata) C. tenuis comb. nov. (syn. T. tenuis) Cordyceps piperis comb. nov. (syn. T. piperis) Dothiorella moneti sp. nov. D. santali sp. nov. Hyaloperonospora lobulariae (syn. Peronospora lobulariae) H. rorippae-islandicae (syn. P. rorippae-islandicae) H. sisymbrii-sophiae (syn. P. sisymbrii-sophiae) Koralionastetales ord. nov. Lichtheimia blakesleeana comb. nov. (syn. Absidia blakesleeana) L. hyalospora comb. nov. (syn. Tieghemella hyalospora) Lichtheimiaceae fam. nov. Neofusicoccum pennatisporum sp. nov. Orbiocrella gen. nov. O. hirsutellae comb. nov. (syn. T. hirsutellae) O. petchii comb. nov. (syn. Torrubiella petchii) O. pruinosa comb. nov. (syn. T. pruinosa) O. truncata comb. nov. (syn. T. truncata) Pontogeneia microdictyi sp. nov.
0953-7562/$ – see front matter doi:10.1016/j.mycres.2009.02.001
journal homepage: www.elsevier.com/locate/mycres
Mycological Research News1 In this issue Systematics and evolution in Torrubiella (pp. 279–289). Activation tagging of Antrodia cinnamomea (pp. 290–297). Genetic diversity in Phytophthora nemorosa and P. pseudosyringae (pp. 298–307). Species delimitation in Hyaloperonospora (pp. 308– 325). Genetic variation and relationships in Laetiporus sulphureus s. lat. (pp. 326–336). Botryosphaeriaceae from Eucalyptus gomphocephala woodland (pp. 337–353). A polyketide synthase gene from Solorina crocea (pp. 354–363). Electrostatic attraction of conidia of Oidium lycopersici (pp. 364–372). Koralionastetales, a new order of marine Ascomycota (pp. 373–380). Laccases in Pleurotus species with different pathogenic behaviour (pp. 381–387). A non-lethal Candida albicans mutant with protective properties against wild-type strains (pp. 388–390). Didymella pisi sp. nov., the teleomorph of Ascochyta pisi (pp. 391–400).
Palaeomycology: do we consider extinct lineages in the evaluation of fossil fungi? In the News section of the April issue of Mycological Research, Thorn et al. (2008) question our finding of a Cretaceous carnivorous fungus that is not assignable to modern representatives (Schmidt et al. 2007). However, while criticizing our interpretation of the fossil, they only explain what modern carnivorous fungi of the genus Dactylellina (Orbiliaceae, Ascomycota) look like. The differences of the fossil to modern taxa were already mentioned in our paper and are, on its own, insufficient to evaluate a 100 Myr old fossil. It is our intent not only to respond to their note, but also to encourage discussion on palaeomycology in general. The study of fossils is often considered to be less important when tracing the evolutionary history of fungi. Compared to animals and plants, well-preserved and well-determinable fungi are rare in the fossil record. Therefore, molecular phylogenies are accepted as more convincing. However, despite great advances in molecular approaches, the study of fossils provides insights into the evolutionary history that would not be possible using modern taxa alone. Molecular studies provide estimates of the actual phylogeny, which only wellpreserved and well-dated fossils can prove and calibrate.
Furthermore, and this is probably much more important, the study of modern taxa alone cannot uncover extinct lineages. Every modern species has an ancestor in Earth’s history, but, by far, not every species had a descendant. But in contrast to palaeozoology and palaeobotany, the occurrence of extinct taxa seems not to be allowed for fungi; indeed, the structures of fungal fossils are mostly interpreted only with reference to modern taxa. Palaeobotanists and palaeozoologists already found that it is more appropriate to investigate and to evaluate the functional morphology of a fossil before comparing it to extant forms. This avoids possible misinterpretations based only on comparisons to modern species. Thorn et al.’s comment reflects the problem of different approaches in different research fields. The discovered amber-preserved fungus possessed hyphal rings and formed blastospores that initiated a yeast stage. Thorn and his co-authors question the existence of such a fungus because no predatory fungus possessing regular yeast stages and single-celled trapping rings is known from modern ecosystems. Would they too, explain to a vertebrate palaeontologist who just excavated an articulated dinosaur skeleton, that these bones must not belong to a single specimen because modern birds look different? Further, Thorn et al.’s doubt is based solely on the few images of our preliminary report in the Brevia section of Science (Schmidt et al. 2007), not on the extensive description of this fossil that we provided elsewhere (Schmidt et al. 2008). A Mesozoic fungus must not necessarily be assignable to a modern group. When working exclusively with molecular phylogenies of extant taxa, that representatives of extinct lineages in the Earth’s history may have had other features is rarely considered. In criticizing our interpretation, Thorn et al. only refer to a single group of modern carnivorous fungi with rings as trapping devices that show differences to the rings of the fossil. Modern predatory fungi, however, are not a monophyletic but an ecological group with different traps, such as adhesive hyphae, sessile and stalked adhesive knobs, adhesive networks, or constricting and non-constricting rings. It is therefore not improbable that in the Earth’s history there were also other groups of fungi with analogous trapping devices occupying the same ecological niche in soil ecosystems. Furthermore, Thorn et al. suggest that the fossil trapping rings would not have functioned because: (1) they are also found
1 Mycological Research News is compiled by the Associate Senior Editor, David L. Hawksworth, Departamento de Biologı´a Vegetal II, Facultad de Farmacia, Universidad Complutense de Madrid, Plaza Ramo´n y Cajal, Ciudad Universitaria, ES-28040 Madrid, Spain (e-mail: [email protected]), to whom items for inclusion should be sent. Unsigned items are by the Associate Senior Editor.
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detached from the mycelium: (2) sticky rings could not work at all: and (3) the illustrated fossil nematodes are too slender to become trapped. These remarks also do not stand up to critical examination. In the specimens preserved in amber, it is very likely that the rings did not detach by intensive struggling of trapped nematodes, but when being overflowed by the resin. Sticky hyphal loops are widespread in carnivorous fungi trapping with adhesive networks (e.g. Dove 1987: figs 22–24). In adhesive traps, the actual diameter of loops and nematodes is less important. Furthermore, the maximum diameter of nematodes has a wide width range depending on the species and the age of the animals. We found four taxa of nematodes of different size in amber piece ARC 115. For the Science Online Material, we decided to select images of the best-preserved individual and of that nematode being very closely located to a trapping ring. Finally, Thorn et al. even question palaeomycology in general, and state that the morphology of fossil fungi would remain suggestive but inconclusive for identification. Hereby, they deny the great progress made in palaeomycology, especially in the last two decades. Increasing interest in this field has led to a plethora of newly discovered fossil fungi preserved in amber, chert, and sediments, which provide relevant diagnostic features and demonstrate that it is highly informative to examine fossils as well as to study molecular phylogenies (e.g. Taylor et al. 2004; Taylor & Krings 2005; Fleischmann et al. 2007; Do¨rfelt & Schmidt 2007). Amazing evolutionary stasis is evident for some groups in the Phanerozoic (e.g. chytrids), but also archaic taxa occur amongst them (e.g. Schmidt 2006). Organisms with intermediate features did not just occur during branching of the respective major groups in deep time, but sometimes persisted for millions of years. Even in the piece of amber which encloses the carnivorous fungus, a fossil was preserved that sheds new light on the early structure of feathers (Perrichot et al. 2008), although feathers of more advanced development already existed at least 50 Myr before that particular resin piece solidified. We thank Kerstin Schmidt (Jena) for discussion. Do¨rfelt H, Schmidt AR, 2007. A conifer seedling with two herbicolous fungi from the Baltic amber forest. Botanical Journal of the Linnean Society 155: 449–456. Dove A, 1987. Ra¨uberische Pilze. Brehm-Bu¨cherei, Wittenberg Fleischmann A, Krings M, Mayr H, Agerer R, 2007. Structurally preserved polypores from the Neogene of North Africa: Ganodermites libycus gen. et sp. nov. (Polyporales, Ganodermataceae). Review of Palaeobotany and Palynology 145: 159–172. Perrichot V, Marion L, Ne´raudeau D, Vullo R, Tafforeau P, 2008. The early evolution of feathers: fossil evidence from Cretaceous amber of France. Proceedings of the Royal Society B, Biological Sciences 275: 1197–1202. Schmidt AR, 2006. Microorganisms and microcoenoses of Cretaceous forests – new insights from amber. In: Barrett PM, Evans SE (eds), Ninth International Symposium on Mesozoic Terrestrial Ecosystems and Biota. Natural History Museum, London, pp. 110–113. Schmidt AR, Do¨rfelt H, Perrichot V, 2007. Carnivorous fungi from Cretaceous amber. Science 318: 1743. Schmidt AR, Do¨rfelt H, Perrichot V, 2008. Palaeoanellus dimorphus gen. et sp. nov. (Deuteromycotina): a Cretaceous predatory fungus. American Journal of Botany 95: 1328–1334. Taylor TN, Krings M, 2005. Fossil microorganisms and land plants: associations and interactions. Symbiosis 40: 119–135.
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Taylor TN, Klavins SD, Krings M, Taylor EL, Kerp H, Hass H, 2004. Fungi from the Rhynie chert: a view from the dark side. Transactions of the Royal Society Edinburgh, Earth Sciences 94: 457–473. Thorn RG, Scholler M, Gams W, 2008. Have carnivorous fungi been found in Cretaceous amber? Mycological Research 112: 611–612.
Alexander R. Schmidta, Heinrich Do¨rfeltb, Vincent Perrichotc a Georg-August-Universita¨t Go¨ttingen, Courant Research Centre Geobiology, Goldschmidtstraße 3, D-37077 Go¨ttingen, Germany b Martin-Luther-Universita¨t Halle, Institut fu¨r Geobotanik und Botanischer Garten, Neuwerk 21, D-06108 Halle/Saale, Germany c Paleontological Institute, University of Kansas, Lindley Hall, 1475 Jayhawk Blvd, Lawrence, Kansas KA 66045, USA E-mail: [email protected]
We accept evidence, but not conjecture, regarding fossil fungi We welcome the comments of Schmidt et al. (2009, above) regarding the value of fossil evidence, including evidence of fossil fungi, in providing clues to the past and to the evolution of extant organisms. However, we wish to be very clear that we do not reject fossil evidence, nor do we reject the existence of extinct lineages or the idea that fossil fungi could have had combinations of characters not seen in present-day taxa. Unfortunately, we have to reiterate that the papers by Schmidt et al. (2007, 2008) did not present any such evidence. None of the photographic illustrations in either of their papers provides evidence that: (1) the rings shown caught nematodes: or (2) that the organism producing the rings and the one producing the yeast-like blastospores were connected as one fungus. These conjectures were only supported by a drawing that made the connections for which no photographic evidence was supplied, and the specimens on which their reports were based in the Paris Museum were not then available for loan to us so that their conjecture could not be corroborated. In our opinion, what Schmidt et al. (2008) described as Palaeoanellus dimorphus and purported to be a Cretaceous predatory fungus is, in fact, an amalgam of unconnected, unrelated parts, neither of which was nematophagous. In addition, we wish to draw the attention to what Do¨rfelt & Schmidt (2007) described as the new Gonatobotryum piceae, also in amber, which can clearly be recognized as two species of Chloridium as described by Gams & Holubova´Jechova´ (1976). Our comments are in no way a criticism of other fine, careful work in paleomycology that both we (Thorn et al. 2008) and they (Schmidt et al. 2009, above) have cited. Do¨rfelt H, Schmidt AR, 2007. A conifer seedling with two herbicolous fungi from the Baltic amber forest. Botanical Journal of the Linnean Society 155: 449–456. Gams W, Holubova´-Jechova´ V, 1976. Chloridium and some other dematiaceous hyphomycetes growing on decaying wood. Studies in Mycology 13: 1–99. Schmidt AR, Do¨rfelt H, Perrichot V, 2007. Carnivorous fungi from Cretaceous amber. Science 318: 1743. Schmidt AR, Do¨rfelt H, Perrichot V, 2008. Palaeoanellus dimorphus gen. et sp. nov. (Deuteromycotina): a Cretaceous predatory fungus. American Journal of Botany 95: 1328–1334.
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Schmidt AR, Do¨rfelt H, Perrichot V, 2009. Palaeomycology: do we consider extinct lineages in the evaluation of fossil fungi? Mycological Research 113: 275–276. Thorn RG, Scholler M, Gams W, 2008. Have carnivorous fungi been found in Cretaceous amber? Mycological Research 112: 611–612.
reclassified as Lichtheimia dubia by Vuillemin (1904), and so Lichtheimia is the name to be taken up. The following nomenclatural changes are therefore necessary:
R. Greg Thorna, Markus Schollerb, Walter Gamsc Department of Biology, University of Western Ontario, 1151 Richmond Street North London, Ontario, N6A 5B7, Canada b Staatliches Museum fu¨r Naturkunde, Erbprinzenstr. 13, D-76133 Karlsruhe, Germany c Molenweg 15, 3743 CK Baarn, The Netherlands E-mail: [email protected]
Coloniae 37–42 C celeriter, 55 C tarde crescentes. Stolones et rhizoidea saepe praesentes. Sporangiophora erecta vel partim arcuata, partim racemosa, sporangia saepe terminalia ferentia. Sporangia sphaerica vel subpyriformia, apophysata. Septum nonnumquam sub sporangio praesens. Columellae sphaericae vel hemisphaericae. Sporangiosporae sphaericae vel ellipsoideae. Cellulae giganteae frequentes, magnitudine variabiles. Suspensores magnitudine fere aequales, appendicibus carentes. Zygosporae crassitunicatae, nudae, fuscae, rasiles, sphaericae vel doliiformes, nonnumquam circulis aequatorialibus praeditae.
a
Mycocladus vs. Lichtheimia: a correction (Lichtheimiaceae fam. nov., Mucorales, Mucoromycotina) Hoffmann et al. (2007), in a revision of Absidia s. lat., reintroduced the generic name Mycocladus Beauve´rie 1900 for a closely related group of thermotolerant species (temperature optimum 33–37 C) with often terminal sporangia, and zygospore suspensors lacking appendages. Upon closer inspection, this genus cannot be used for these fungi because its type, M. verticillatus, was described as lacking terminal sporangia, having appendages on the columella and subsporangial septa, and growing optimally at 30 C and not above 40 C, thus characteristic of Absidia s.str. The main morphological parameters of the asexual structures of M. verticillatus come as close as possible to those of Absidia caerulea (unnecessarily orthographically ‘corrected’ to A. coerulea in some recent literature) or A. glauca. But the zygospores were described as lacking suspensors and covered with scales, a feature unknown in either group of species and causing some confusion. The scaled exospore may be taken as the tubercular exospore of a Mucor-like zygospore as developed by the mycotrophic Lentamyces parricida (Hoffmann & Voigt 2009). This assumption is supported by Beauve´rie’s (1900) observation of parasitic interactions with other moulds. In all likelihood, Beauve´rie observed a co-culture between a mesophilic Absidia and a mycotrophic Lentamyces. Consequently, the type species of Mycocladus is not congeneric with the thermotolerant Absidia-like species and the corresponding family name Mycocladaceae (orthographically wrongly given as Mycocladiaceae in the original publication) cannot be retained in the sense intended because it was based on a taxonomically different type. Looking for alternative solutions, the next candidate genera to consider to accommodate the thermotolerant group are Lichtheimia (Vuillemin 1903: 126) and Pseudoabsidia (Bainier 1903: 155; as ‘Pseudo-Absidia’), both published in the same issue of the Bulletin de la Socie´te´ Mycologique de France. Lichtheimia was typified by L. corymbifera, named in honour of the Swiss mycologist Lichtheim. Bainier (op. cit.) was the first to described rough-walled zygospores with equatorial ridges for Pseudoabsidia vulgaris, based on Absidia dubia Bainier 1882. The erroneous choice of the epithet was corrected in the same year by Sydow (1903), who made the combination Pseudoabsidia dubia. That rather confused species was already
Lichtheimiaceae K. Hoffm., G. Walther & K. Voigt, fam. nov. MycoBank no.: MB508680
Typus: Lichtheimia Vuill. 1903. Lichtheimia Vuill. Bull. Soc. mycol. Fr. 19: 126 (1903). Colonies rapidly-growing mainly at optimum temperatures between 37 C and 42 C, predominantly thermotolerant until max. 55 C, non-phototrophic. Hyphae often forming stolons and rhizoids and terminal sporangia. Hyphae and sporangiophores unseptated, unbranched, rarely sporangiophores with subsporangial septum and subsporangial whorls forming terminal sporangia. Sporangiophores erect or slightly bent. Sporangia multi-spored, spherical or subpiriform, apophysate. Collumellae spherical or hemispherical, occasionally conical. Sporangiospores spherical or ellipsoidal. Giant cells abundant or occasionally developed, irregularily shaped (pleomorphic) with finger-like projections. Zygospores developing from opposed gametangia, globose to oval, thick-walled, naked, smooth and less ornamented epispore, dark brown, suspensors more equal less inequal in size, non-appendaged, occasionally developing equatorial rings surrounding the zygospores. Type: Lichtheimia corymbifera (Cohn) Vuill. 1903. Lichtheimia corymbifera (Cohn) Vuill., Bull. Soc. mycol. Fr. 19: 126 (1903). MycoBank no.: MB416447 Basionym: Mucor corymbifer Cohn, in Lichtheim, Z. Klin. Med. 7: 149 (1884). Synonym: Mycocladus corymbifer (Cohn) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 95 (1979); as ‘corymbifera’. Lichtheimia ramosa (Zopf) Vuill., Bull. Soc. mycol. Fr. 19: 126 (1903). MycoBank no.: MB416448 Basionym: Mucor ramosus Zopf, in Schenk, Handb. Botanik 4: 587 (1890). Synonyms: Mucor ramosus Zopf, in Lindt, Arch. Exp. Path. Pharmacol. 21: 269 (1886); nom. illegit. (Art. 53). Mycocladus ramosus (Zopf) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 95 (1979). Lichtheimia blakesleeana (Lendn.) K. Hoffm., G. Walther & K. Voigt, comb. nov. MycoBank no.: MB512831 Basionym: Absidia blakesleeana Lendn., Bull. Soc. Bot. Gene`ve, Se´r. 2, 15: 149 (1924).
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Synonym: Mycocladus blakesleeanus (Lendn.) J.H. Mirza, in Mirza et al., Mucor. Pakistan (Faisalabad): 94 (1979). Lichtheimia hyalospora (Saito) K. Hoffm., G. Walther & K. Voigt, comb. nov. MycoBank no.: MB512830 Basionym: Tieghemella hyalospora Saito, Zentbl. Bakt. ParasitKde, Abt. 2, 17: 103 (1906). Synonyms: Absidia hyalospora (Saito) Lendn., Mat. Fl. Cryptog. Suisse 3(1): 142 (1908). Mycocladus hyalosporus (Saito) J.H. Mirza, in Mirza et al., Pakistan (Faisalabad): 97 (1979). For additional synonyms of these species see Hoffmann et al. (2007). We wish to express our gratitude to Walter Gams (Baarn, The Netherlands) for critically reading the manuscript, and Gerald L. Benny (University of Florida, Gainsville, USA) and Paul M. Kirk (CABI Biosciences-Europe, Egham, UK) for valuable advice on taxonomic interpretations. We thank Sigrid Neuhauser (University of Innsbruck, Austria) for accessing French literature databases. This work was supported by a grant of the Deutsche Forschungsgemeinschaft to KV (VO772/9-1). Bainier G, 1903. Sur quelques espe`ces de Mucorine´es nouvelles ou peu connues. Bulletin de la Socie´te´ mycologique de France 19: 153–172. Beauve´rie J, 1900. Mycocladus verticillatus. Annales de l’Universite´ de Lyon 3: 162–180. Hoffmann K, Discher S, Voigt K, 2007. Revision of the genus Absidia (Mucorales, Zygomycetes): based on physiological, phylogenetic and morphological characters: Thermotolerant Absidia spp. form a coherent group, the Mycocladiaceae fam. nov. Mycological Research 111: 1169–1183. Hoffmann K, Voigt K, 2009. Absidia parricida plays a dominant role in biotrophic fusion parasitism among mucoralean fungi (Zygomycetes): Lentamyces, a new genus for A. parricida and A. zychae. Plant Biology, doi: 10.1111/j.1438–8677.2008.00145.x. Sydow H, 1903. Referate und kritische Besprechungen. Annales Mycologici 1: 371. Vuillemin P, 1903. Le genre Tieghemella et la se´rie de Absidie´es. Bulletin de la Socie´te´ mycologique de France 19: 119–127. Vuillemin P, 1904. Le Lichtheimia ramosa (Mucor ramosus Lindt), champignon pathoge`ne, distinct du L. corymbifera. Archives de Parasitolologie 8: 562–572.
Kerstin Hoffmanna, Grit Waltherb, Kerstin Voigta a Fungal Reference Centre, Institute of Microbiology, University of Jena, Neugasse 24 D-07743 Jena, Germany b CBS Fungal Biodiversity Centre, P.O. Box 85167, 3508 AD Utrecht, The Netherlands E-mail: [email protected]
Fungal compounds can detrimentally affect diagnoses and phylogenetic analyses As molecular methods assume an increasing role in the identification of fungi and also in phylogenetic analyses, it is essential that users are aware of possible caveats that need to be considered when using them. In fungi that produce bioactive extrolites, especially compounds that are established mutagens, such as aflatoxins, Paterson et al. (2008) point out that these have the potential to inhibit DNA stabilizing enzymes. Further, in the case of examination for genes involved in mycotoxin production, they
stress that this problem could lead to incorrect conclusions as to the safety of particular isolates. In addition, as the culture medium can affect compound expression, growing fungi in media with inhibitors and mutagens could alter the DNA. While many fungi survive the mycotoxin levels they produce in nature, these may accumulate to such high concentrations in broths and agars that they can be detrimental. If different media are employed when growing fungi for DNA extraction, this could affect the comparability of phylogenetic results. In addition, even if the same medium is employed, each taxon, or even strain, may produce different bioactive extrolites qualitatively and/or quanitatively, hence potentially affecting results. The problems has been recognized for over a decade, especially by mycologists working with mycotoxins, and Paterson et al. (2008) provide many examples from the literature and draw attention to cases where the findings have been compromised. In order to avoid such potential problems in the case of PCR inhibition, it is suggested that internal amplification controls (IACs) are adopted, and even made mandatory for mycotoxin gene detection. The IACs proposed are sequences that will provide a PCR product using the same primers being employed but which will not coincide with the product from the target gene. However, for DNA mutation and stabilisation, the answer lies in ensuring extrolites are not produced in culture. This paper brings to the fore issues that merit the serious attention of all who use cultured fungi in either molecular diagnostics or phylogenetic systematics. Paterson RRM, Sariah M, Lima N, Zainal Abidin MA, Santos C, 2008. Mutagenic and inhibitory compounds produced by fungi affect detrimentally diagnosis and phylogenetic analysis. Current Bioactive Compounds 4: 245–257.
New scientific names in this issue Aplosporella yalgorensis sp. nov. Conoideocrella gen. nov. C. luteorostrata comb. nov. (syn. Torrubiella luteorostrata) C. tenuis comb. nov. (syn. T. tenuis) Cordyceps piperis comb. nov. (syn. T. piperis) Dothiorella moneti sp. nov. D. santali sp. nov. Hyaloperonospora lobulariae (syn. Peronospora lobulariae) H. rorippae-islandicae (syn. P. rorippae-islandicae) H. sisymbrii-sophiae (syn. P. sisymbrii-sophiae) Koralionastetales ord. nov. Lichtheimia blakesleeana comb. nov. (syn. Absidia blakesleeana) L. hyalospora comb. nov. (syn. Tieghemella hyalospora) Lichtheimiaceae fam. nov. Neofusicoccum pennatisporum sp. nov. Orbiocrella gen. nov. O. hirsutellae comb. nov. (syn. T. hirsutellae) O. petchii comb. nov. (syn. Torrubiella petchii) O. pruinosa comb. nov. (syn. T. pruinosa) O. truncata comb. nov. (syn. T. truncata) Pontogeneia microdictyi sp. nov.
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