Xylaria insolita and X. subescharoidea: two newly described species collected from a termite nesting site in Hua-lien, Taiwan.

Background: A number of Xylaria species are exclusively associated with nests of macrotermitine termites. A nesting site of Odontotermes formosanus in eastern Taiwan, which is the only macrotermitine termite known on the island, had been inundated during the raining season of 2010, and hundreds of Xylaria stromata emerged from it thereafter. A thorough examination of these stromata showed that they represent a mixture of different species.

Results: Five Xylaria species were identified from the stromata collected from the nesting site, including two undescribed species, which are newly described as X. insolita and X. subescharoidea herein, and three known species X. brunneovinosa, X. escharoidea, and X. furcata.

Conclusion: Totally, there are 28 Xylaria species growing on termite nests or ground in the world. Although O. formosanus is the only macrotermitine species known in Taiwan, the Xylaria diversity associated with its nests is fairly high; the species number has reached 12 with X. furcata, X. insolita, and X. subescharoidea added to the Taiwan mycobiota.