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Myco-talpology is the science of mushrooms and talpid moles based on our discovery in 1976 that underground mole nests can be located by the aboveground fruiting of the agaricsHebeloma danicumorHebeloma sagarae, a Japanese sibling species of EuropeanHebeloma radicosum. Hyphae of these mushrooms specifically colonise mole latrines near nests, forming ectomycorrhizas with the roots of their host trees. By this process, the hyphae and roots absorb, transform, and translocate the nutrients from mole excretions, cleaning the mole’s habitat. The mushrooms fruit on the ground with thick root-like tissue stretching up from the ectomycorrhizas. The presence of the fruit bodies serves as the only indicator for underground mole nests, enabling us to provide novel insights into mole ecology. We excavated 74H. sagaraeorH. danicumsites in Japan and 13H. radicosumsites in Europe and identified the nesting species. These investigations provided new perspectives on latrine making, nest structure, breeding and nestlings, the neighbouring presence of different Talpini species, and long-term nesting at the same site with inhabitant changes. Moreover, they suggested that a tripartite habitat-cleaning symbiosis among moles, mushrooms, and mushroom-host trees in the latrine must have existed for a long time in Japanese and European forests. While moles are traditionally considered inhabitants of open areas, their special relationship with mushrooms and trees suggests they may originally be forest inhabitants.

It has been known that the agaric fungus Hebeloma radicosum fruits from mole latrines located in the ground and that ectomycorrhizas develop within the same latrines. But the identity between the fruit bodies on the ground and the mycosymbionts of the ectomycorrhizas below ground has not been established. Molecular genetic data revealed that the fungal hyphae composing the ectomycorrhizas are identical with the fruit bodies of H. radicosum. Furthermore, phylogenetic analysis clearly separated H. radicosum and H. radicosoides, suggesting that they are truly different species.

A new ammonia fungus, Coprinopsis austrophlyctidospora, is described from Nothofagus and Pinus forests in New Zealand and from Eucalyptus forest in Australia. In ecology and macro-morphology, this species is similar to the Northern Hemisphere species C. phlyctidospora, but the new species differs in morphological characters of the basidiospore, i.e., in having a plage, more minute surface warts, and the smaller size of the basidiospore.

Hebeloma radicosum fructification occurred in 2003 in Hokkaido where Talpidae moles, known causal animals for H. radicosum growth, are not distributed. An excavation carried out in 2005 revealed a mass of deserted latrines and a collapsed nest in the soil. The latrines, being full of deteriorating ectomycorrhizas, were considered to have borne that fungal growth. The responsible animal was identified as a shrew (Sorex) species by the characteristics of hairs remaining in the soil. Thus, in addition to the moles (Insectivora, Talpidae) and the wood mouse (Rodentia, Muridae; in Europe), a shrew species (Insectivora, Soricidae) is found to cause H. radicosum growth.

Three cases of Hebeloma radicosum growth on the wood-mouse latrine near a wood-mouse nest are here described from Switzerland. This study establishes that this fungus may associate with wood mice, besides associating with moles as has been previously known. The nest occupant and the latrine maker were independently identified to ensure that the two were not different. For this identification, the characteristics of fallen hairs found from the nest and of those found from the deserted latrines now colonized by the fungus were taken as the most important information. In addition to these case studies, information about the occurrence of H. radicosum in northern Europe and northern Japan (Hokkaido) where moles do not occur is presented, which explicitly indicates the possibility of customer animals other than moles.

The behaviour of Suillia flies on basidiocarps of Hebeloma radicosum was studied in central Japan. Hebeloma radico-sum is a peculiar fungus that fruits only on talpid mole middens, near the moles' nests. All insect species around selected basidiocarps of this mushroom species were observed, their behaviour studied, and identified in late October to early November 1992, and again briefly in 2001. During these periods, Suillia flies were seen on the basidiocarps, while other insect species were rarely observed. Usually one Suillia fly (male) occupied one basidio-carp and prevented other conspecifics from occupying the same basidiocarp. This appeared to be pre-mating territorial behaviour. Larval stages of Suillia are known to be mycophagous, and the territorial behaviour is presumably performed to defend oviposition sites. This is the first report from Asia on ecological aspects of Suillia flies.

Coprinopsis phlyctidospora (syn: Coprinus phlyctidosporus) from the Netherlands, Japan, New Zealand, and Australia can be segregated into two groups, northern and southern, based on the nucleotide sequences of their ITS regions. The mating type of a C. phlyctidospora isolate was tetrapolar. Mating reactions were compatible between monokaryotic testers derived from basidiospores of a Japanese isolate and dikaryotic isolates obtained from a wide geographic area in Japan. In contrast, mating between the Japanese monokaryotic and dikaryotic isolates from Australia and New Zealand were incompatible. These results indicated that C. phlyctidospora was complex and individuals currently recognized as C. phlyctidospora in the Northern Hemisphere and those in the Southern Hemisphere are distinct taxa. The relationship between the clades and the biogeography of the C. phlyctidospora complex are also discussed.

Responses of the long-rooting agaric Hebeloma radicosum fruit-bodies to light and gravity were studied. In light from below or obliquely below, fruit-bodies grew straight downward with gills tilted and cap swollen and waved if they had emerged downward from the culture medium, or bent upward from the beginning if they had emerged obliquely downward. In light from above or obliquely above, they grew upward if they had emerged upward. Thus, they did not grow toward unilateral light from obliquely below or obliquely above, and hence their growth was nonphototropic and negatively gravitropic from the beginning of development. Even the straight downward growth seems to be latently negative-gravitropic. In the dark, fruit-bodies grew upward, forming pseudorhizas, but they remained immature; they matured only in the light. These characteristics may be related to the growth habits of the fungus colonizing deep in the ground, forming primordia there, and developing mature fruit-bodies on the ground.

Our previous study revealed that, when exposed to light from below, fruit-bodies of humus-borne agarics grow straight downward both in the ‘Coprinus Type’ and ’Non-Coprinus Type’ species and that, in the latter, gills tilt by gravitropism, caps swell and wave, and stipes twist. The present study revealed that fruit-bodies of some lignicolous agarics also grew straight downward. Among themFlammulina velutipes andHypsizygus marmoreus fruit-bodies showed almost the same behaviour as the ‘Non-Coprinus Type’, butPleurotus ostreatus (assumedPolyporus Type) fruit-bodies did not show the gill tilting and cap waving. Rather, it redifferentiated to produce new gills or new fruit-bodies, possibly by gravimorphogenesis, or formed spiral stipes. Based on these results, graviresponses in hymenomycetes are overviewed.

Fruit-bodies of Agaricales are known to show positive phototropism during the early stage of development, but negative gravitropism at the later stage after the onset of basidiospore formation. However, when exposed to light from below, the fruit-bodies ofTephrocybe tesquorum andCoprinus spp. grew downward through all stages of development, even after the onset of basidiospore formation. Primordium formation, fruit-body development and basidiospore formation were not disturbed under such conditions. In these downward-growing fruit-bodies, gills stood straight upward. InT. tesquorum, caps often became swollen and stipes sometimes became twisted anticlockwise, contrary to those in light from above, while such behaviours were not observed inCoprinus spp.

A new tripartite relationship among animals, fungi, and plants, based on formation of ectomycorrhiza and on removal of animal wastes, is described. In forest habitats where animal wastes such as urine or faeces or dead bodies, mainly of mammals, have been deposited, a particular group of fungi form reproductive structures successionally after the apparent decomposition of the wastes. This natural event can be simulated by application to the soil of urea, aqueous ammonia, or nitrogen compounds that release ammonia on decomposition. Both field observations and simulation experiments show that, when these events take place in forests of ectomycorrhizal trees, ectomycorrhizal fungi fruit during the late phase in the succession. Ectomycorrhizas are in fact observed in the soils colonized by these fungi. Among these fungi, Hebeloma spp., Laccaria spp., and a few others colonize commonly in various waste sites, while Hebeloma radicosum colonizes specifically in moles’ deserted middens (latrines) near their nests. The animals involved here as waste depositors or cadavers seem not to feed on the fungi and the plants but may depend on them for cleaning their own habitats, since mycorrhizas should readily remove products derived from wastes. The tripartite relationship described may be viewed as a cleaning symbiosis. Key words: animal waste, ammonia, postputrefaction fungi, Hebeloma, ectomycorrhiza, cleaning symbiosis.

Evidence is presented to show that under certain conditions, three species of Japanese talpine mole, Euroscaptor mizura, Mogera wogura, and Mogera kobeae, persistently use the same nest or nesting site. The moles' nesting sites were detected by the fruiting of an agaric species, Hebeloma radicosum, which specifically colonizes a mole's latrines near its nest. The nests were removed to observe the moles' response. During excavation, the moles often returned to the disturbed sites in search of their nests. The nests were soon reconstructed, followed by refruiting of the mushroom. Thus, one nesting site of E. mizura was used for more than 15 years, despite removal of the nest seven times, and another for more than 5 years, a period ended by the capture of the occupant. Similar results were also obtained with M. wogura and M. kobeae. The occupants may have changed generationally at each site. These persistently used sites seem to be associated with well-drained soil and appropriate vegetation.

The vertebrate body can be divided into soft and hard tissues: The former category is composed of muscles, internal organs, veins, and blood, and the latter is composed of bones, hair, horns, hooves, nails, feathers, and bills. Where a cadaver has been left to decompose on the ground and has not been scavenged before or during decomposition, the soft tissues can readily disappear, consumed mainly by invertebrates and bacteria, while the hard tissues endure. Probably for this reason, the hard tissues have long been known to support a specialized group of fungi adapted to this substratum: keratinophilic fungi (Hudson 1972). In contrast, the soft tissues have only relatively recently been shown to yield a particular group of fungi after their disappearance (Sagara 1976b). Similarly, feces, especially of herbivores, have long been known to bear coprophilous fungi (Webster 1970) as they endure, whereas urine and readily decomposing feces have only recently been shown to yield a specific group of fungi (Sagara 1975). These two new groups of fungi are in fact almost identical in species composition and successional development. The present chapter focuses on this neglected aspect of nature and its forensic potential.

Hebeloma vinosophyllum Hongo is a terrestrial agaric originally found in broad-leaved and conifer forests but not described as having any special ecological requirements1. It now seems that this species often fruits where a dead mammal has been buried.