Hydnum sclerodontium Berk. & Mont. (1844)  MycoBank Index Fungorum
  ≡  Pterula sclerodontia (Berk. & Mont.) Lloyd (1922)
  ≡  Tremellacantha sclerodontia (Berk. & Mont.) Jülich (1980)
  ≡  Protohydnum sclerodontium (Berk. & Mont.) Hjortstam & Spooner (1990)
  ≡  Elmerina sclerodontia (Berk. & Mont.) Miettinen & Spirin (2018)

Based on Inaturalist records, it is only found in Southeast Asia and its habitats are declining (30% from 2005 to 2015; 21% projected from 2019-2050 (Estoque et al. 2019). This species is also suspected of population decline exceeding 30% within three generations (50 years) due to its host. So, it can be considered as A4c Vulnerable Near Threatened?

Elmerina sclerodontia is found in Thailand, Malaysia, Indonesia, Brunei Darussalam, Singapore and other countries may also be in Yunnan, China (Malysheva et al., 2018). The species has a fragmented distribution in Southeast Asia.

Based on Inaturalist record, there are 2 populations and 4 subpopulations found in 8 sites (Peninsular Malaysia: Penang, Raub, Kuala Lumpur, Negeri Sembilan, Kluang, Gunung Pulai Recreational Forest; Borneo: Kuching, Batang Ai National Park) in Malaysia, 5 sites (Bukit Batok Nature Park, Upper Seletar reservoir Park, Kranji, Windsor Nature Park, Singapore Botanic Gardens) in Singapore and 2 sites (Bangkok, Pattaya) in Thailand.

 

The species is found on fallen hardwood branches of tree. It has a fragmented distribution in Southeast Asia and has been reported from Thailand, Malaysia, Philippines, Singapore, Brunei Darussalam and Indonesia (personal communication).

There is limited record data of the population trend, but the rainforest in Malaysia, Indonesia and Papua New Guinea have seriously declined due to agricultural activity including oil palm plantations and durian farms (deforestation). There was a 30% loss of forest in southeast Asia from 2005-2015 (Estoque et al. 2019), and this might be continued and projected that the forest cover loss in the region estimated at 21% from 2019 to 2050 (Estoque et al. 2019). Based on 50 year period (3 generations of this species) from 2000 to 2050, forest loss is expected to exceed 50% including the hosts as well as the population of species is suspected to also decline at least 30% within the same timeframe.

This species may be declining and assume that it is only found in protected areas (such as in Singapore) as well as in unprotected areas based on Inaturalist records.

The species is growing on fallen hardwood branches tree, generally in wet condition of forests. Elmerina sclerodontia from Malaysia and Indonesia has used a fallen tree as its host and its species is unknown. It typically begins development underground, and has been found in regions of humid tropical rainforest of southeast Asia. Usually this species is found growing along hills with the soil and decayed wood during rainy season.

Agricultural industry of oil palm trees has led to the deforestation and degradation of humid rainforest habitat and reduced the population of species associated with fallen branches tree species (hosts) from unspecified species but most probably from the family Dipterocarpaceae.

This species is undergoing decline due to host loss of extremely deforestation of agricultural activities and other abiotic factors (temperature) where this species might be unable to survive. Impact on this species such as longer dry seasons caused by El Nino, significant damage is caused to farm activities. It was projected that the magnitude of temperature increase is about 3-5℃ (Ministry of the Environment of Japan).

Sustainable management of forests such as logging activities and agriculture practices should be controlled and implemented policy.

Sustainable forest conservation studies, surveys and the distribution of this species are needed to know their status.

This species is unclear in terms of its use but may have other purposes such as research.

Malysheva, V, Spirin, V., Miettinen, O., Motato-Vásquez, V., Hernawati, Sathiya Seelan, J.S., & Larsson, K.H. 2018. Revision of Protohydnum (Auriculariales, Basidiomycota). Mycological Progress 18:1079–1099

Estoque, R.C., Ooba, M., Avitabile, V., Hijioka, Y., DasGupta, R., Togawa, T. and Murayama, Y. 2019. The future of Southeast Asia’s forests. Nature Communications 10(1829): 1-12.