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The genus Termitomyces was first described by Heim in 1941. This genus belongs to the division Basidiomycota, class Asidiomyces, subclass Agaricomycetidae, order Agaricales, and family Lyophyllaceae. In 1799, German naturalist J.D Koenig working in the East Indies was the first one that observed termite nests that looked like the human brain. G. Garden of England harvested a carpophore-bearing fungus from a termite nest in Ceylon, and Petch (1906) determined the relationship between the termite and the fungus, Temitomyces, which lives in symbiosis with termites. Attine ants are also symbionts with fungi in the genus Leucaogaricus. In some species, the ants and fungi are dependent on each other for survival.

Taxonomic History /Systematics
Taxonomy of Termitomyces has traditionally been base on morphological characteristic observed with a hand lens or microscope. Basidiomes, or mushrooms, are examined in the field and then microscopically, while fresh or after being dried. Recently, Termitomyces identification has involved more molecular techniques and additional macro- and micro-morphological characters. All structures used in morphology-based identification include pseudorhiza (cord-like structure resembling plant roots), pileus (mushroom “cap”) pertoratoria or umbos (the tops of some mushrooms), and basidiocarps (the sporocarp of a basidiomycete, the multicellular structure on which the spore producing hymenium is borne). A synonym of Termitomyces clypeatus is Sinotermitomyces taiwanensis. Termitomyces clypeatus is characterized by a sporocarp with a small to (rarely) medium-sized mushroom. The cap is 6.5 cm in radius, gray to buff-brown, paling towards the margin. The pseudorhiza is more than 13 cm long and white with an enlargement at the base, near the soil surface. The strip of the basidiocarp is narrow, and spores are pink. The mushrooms appear in groups around termite mounds but some grow 120 mm below the ground.

Developments in Classification
The classification of the Termitomyces has been changed a lot. Roger Heim (1942) named this genus and separated it from the other genera in the family. The genus Podabrella was separated from Termitomyces because members of this genus lack a universal veil and do not form symbiotic relationships with termites. Also, Froslev (2003) studied by using T. microcarpus, the type species of Podabrella, the result confirmed that Podabrella was derived from Termitomyces. Sinotermitomyces was distinguished from Termitomyces because of ornamented cystidia and a hollow stipe (Zhang 1992). Also a velar remnant (universal veil or cap) on the pseudorhiza is characteristic of Termitomyces but not present in Sinotermitoyces, so this characteristic is used to distinguish between Termitomyces and Sinometocyes. In 2006, Wei moved five species in the genus Sinotermitomyces to Termitomyces. Sinotermitomyces cavus is synonymous with T. heimii, and S. carnosus, S. graseu and S. rugosicep are all synomymes of T. mammiformis. Sinotermitomyces taiwanensis had firm velar remains and a spiniform perforatorium, characteristics very distinctive to T. clypeatus,. Molecular techniques might change the classification of members of this genus. There are still many Termitomyces species that have not been identified because they do not form fruit bodies. Phylogenetic analyses of large subunit ribosomal DNA (nLSU-rDNA) and the mitochondrial encoding small subunit ribosomal DNA (mtSSU-rDNA) sequences shows that species of Lyophyllum are closely related to Termitomyces.

Phylogenetic Affinities
The phylogenetic relationship of Temitomyces and related taxa has been studied by Froslev (2003). Analysis of samples from Africa and Asia have been performed base on nLSU-rDNA and (mtSSU-rDNA). The results suggest that T. clypeatus isolate from Asian species and T. clypeatus isolate from Africa species are different, because they separated in different clades.

Modern Phylogenetic Research
Nobre et al (2010) studied the dispersion and colonisation of fungi associated with termites in Madagascar by using the mitochondrial gene cytochrome oxidase subunit 1 (COI) and part of the nuclear ribosomal internal transcribe spacer (ITS2) region. The results suggest that fungus-growing termites of Madagascar all originate from a single colonisation. This might imply that vertical transmission has occurred.

Nobre and Aanen (2010) tried to prove hypothesis about the establishment of a new colony. The study found that the vertical transmission of a new colony should have only one clade (monophyletic), but in their study showed that there are three clades. This result showed the evidence of horizontal transmission had occurred. According to two previous researches, we can imply that the vertical transmission should have occurred fist, and the horizontal has occurred later.

Ecology
Termitomyces and termites both prefer hot and humid conditions. Studies suggest that fungus-growing termites originated in the African rain forest, later spread to African savanna and in to Asia and Madagascar. Termites and Termitomyces have a symbiotic relationship and cannot reverse to nonsymbiotic states.

Geographic Distribution
Termitomyces are found in Africa, Asia and Madagascar. Termitomyces clypeatus is known to occur in Asia, in Thailand, China, and Malaysia. In Africa, T. clypeatus is found in Burundi,.

Habitat Preferences
Termitomyces clypeatus is associated with termites in species of Macrotermes gilvus and Hypotermes makhamensis. Termitomyces isolates have always been found in association with termites, and the symbiont termites cannot survive without the fungus. Not all species of Termitomyces can associate with all species of Macrotermitinae; there is host specificity.

Reproductive Biology
Termites chew and swallow wood, leaves or grasses, and Termitomyces grow on these materials, producing mycelia and white nodules (asexual fruiting bodies covered with conidia). The fruit bodies develop from combs (made from macerated woody material, gathered by foraging workers (termite) that is chewed up and swallowed), produce spores and disperse.Some studies about mating types have been done. Lincht et al (2005) studied spores cultured from a comb and single spore. They found that a cell germinated from a basidiome, collected from a mound, was stained with DAPI (4',6-Diamidino-2-Phenylindole, use for double DNA staining) and the cell has three nuclei. While a cell germinated from a comb culture has five nuclei. In addition, basidiospores contained one nucleus. In conclusion, the study showed that the cell in the comb cultures and single spore cultures had multiple nuclei in each cell. Another significant study by Linche et al (2005), they use DNA sequences from the internal transcription space (ITS) region to examine spores from comb culture. The results showed that the spores from comb culture are heterokaryotic, while the single spore cultures are homokaryotic. This evidence implies that Termitomyces spores are sexual spores.

Host Distribution/Associations
Termites in the subfamily Macrotermitinae are associated with fungi in the genus Termitomyces. In 2007, Aanen et al. elucidated the interaction specificity between termites and fungi in the genus Temitomyces. They sampled fungus-growing termites from 101 colonies in South-Africa and Senegal. These fungus-growing termites were identified as belonging to the genera Microtermes, Macrotermes and Odontotermes. They sequenced ITS regions of fungi and found that some termites were associated with a single species of Termitomyces, while others were associated with multiple species. How are these associations established and maintained? Are they maintained through horizontal transmission (the symbiotic partner is collected from the environment upon establishment of a new colony) or vertical transmission (inherit their symbiont from the parental colony). All of these questions remain unanswered.