R-L categories correct, but text here does not match final assessment. Updated version will be published in IUCN´s Red List June or Nov 2019.
Neohygrocybe ovina is an easily identified waxcap distributed throughout most European countries and Russia (eastwards to Ural region; Kovalenko 1989). It is a member of a rich and diverse fungal community inhabiting old semi-natural grasslands. The conservation value of these habitats is very high since they are characterized by many rare and endangered fungal species (mostly belonging to Clavariaceae, Geoglossaceae, Hygrocybe s. l., Entoloma, and Dermoloma). Available habitats of this species in Europe are declining heavily due to abandonment of traditional systems, lack of extensive grazing and mowing, fertilisation, modification of farming practices and agricultural intensification (EEA 2015).
The inferred population size of this species exceeds 20,000 mature individuals, therefore criterion A is applicable. The estimated reduction of the population in Europe is at least 30% over 30 years (past, ongoing and future) but may be even higher, up to 50% over three generations (50 years). Additionally, the decline in area and quality of available grassland habitats has exceeded 30% over the last 50 years. This meets the threshold IUCN category Vulnerable (VU) A2c+3c+4c.
According to Lodge & al. (2013) H. ovina belongs to the genus Neohygrocybe and the correct name for this taxon is Neohygrocybe ovina (Bull.) Herink.
There is a similar North American species Neohygrocybe subovina (Hesler & A.H. Sm.) Lodge & Padamsee described by Hesler & Smith (1963). The same authors also reported N. ovina in North America. In GBIF portal there are 23 records of this species from the USA.
At least some North American collections should be compared with original European specimens by molecular and morphological methods. Until then, the species is treated as distributed in Europe only.
Synonym: Hygrocybe nitiosa (A. Blytt) M.M. Moser
Neohygrocybe ovina is remarkable and easily identified Waxcap species. It is characterized by dark greyish brown to almost black basidomata that turn reddish when bruised. Its habitats are extensively managed semi-natural grasslands and lawns. These types of habitats are increasingly threatened and declining throughout the whole of Europe. It is included in many European national Red Lists.
Neohygrocybe ovina is distributed in most European countries and the European parts of Russia.
The area covered with traditionally managed semi-natural grasslands is continuously decreasing throughout the whole of Europe. The fragmentation and loss of suitable habitats is caused by intensification of current agricultural practices, grassland conversion and land abandonment. Over the last century, more than 90% of semi-natural grasslands have been lost in Europe (EEA Report 3/2016). Ridding et al. (2015) showed that semi-natural grassland sites categorised into four grassland types declined considerably in England between 1960 and 2013, with a total loss of 47%. The situation is similar in other European countries (EEA report 3/2016).
The population size of Neohygrocybe ovina probably exceeds 20,000 mature individuals. Its population is decreasing heavily due to the abandonment of traditional farming methods employed in semi-natural grasslands (extensive grazing and/or regular hand mowing). The projected reduction of population in Europe is at least 30% over 30 years (past, ongoing and future) but may be even higher, up to 50% over three generations (50 years; e.g. 2000-2050). Moreover, decline in area and quality of suitable grassland habitats has exceeded 30% over the last 50 years. The species is assessed as threatened (mostly in categories EN and CR, rarely in VU) in the majority of national fungal Red Lists in Europe (e.g. Austria, Croatia, Czech Republic, Denmark, Finland, Germany, Netherlands, Norway, Poland, Sweden etc.).
Population Trend: Decreasing
Neohygrocybe ovina is a member of species rich fungal communites occurring in traditionally managed old semi-natural grasslands. These habitats are characterized by low levels of available nitrogen and phosphorus in the soil, and by low vegetation. The management regime includes a longtime regular but extensive grazing (by cattle, horses, sheep, deer) or regular hand mowing with subsequent sward removal. Suitable habitats host many rare and endangered macrofungal species, especially those from families Clavariaceae and Geoglossaceae, and genera Camarophyllopsis s. l., Hygrocybe s. l., Entoloma, and Dermoloma. For a long time species of Hygrocybe s. l. were considered to be saprotrophs. The latest research of Halbwachs et al. (2018) based on analysis of stable isotopes in fruitbodies of some Hygrocybe species suggested that these fungi are endophytes or could possibly form mycorrhizal relationships with plants.
The main threat causing the decline of Neohygrocybe ovina is the continuing decrease of available, high-quality semi-natural grasslands. These habitats are dependent on small scale traditional farming which evolved over centuries of land use by local people. Decline in area, increasing fragmentation, and loss of diversity were dominant trends in European semi-natural grasslands for centuries (Rounsevell et al. 2018). Recently, these habitats have also been rapidly lost due to management intensification or abandonment in a number of European countries (EEA Report 3/2016). The main agriculture-related pressures/threats to grassland habitats are abandonment of traditional systems, lack of grazing, lack of mowing, fertilisation, modification of cultivation practices and agricultural intensification (EEA 2015). It has a strong negative effect on fungal communities occurring in traditional semi-natural grasslands. Therefore, many grassland fungal species dependent on traditional extensive management practices have become threatened. In contrast to traditional management, the more recent intensification of farming has resulted in a dramatic decline of grassland biodiversity in other groups of organisms as well. A strong decline of grassland birds and a 45% decline in the butterfly population is reported for Western Europe in recent decades (Rounsevell et al. 2018).
The existence of N. ovina depends on the protection of valuable semi-natural grassland sites and their active management. The most valuable sites, characterized by a high diversity of macrofungal species (e.g. Hygrocybe, Entoloma, Dermoloma, Geoglossaceae, Clavariaceae) that have similar nutrient and management requirements, should be primarily protected in Europe. Some grassland sites with high fungal diversity are already within protected areas. Inadequate grassland management methods are sometimes employed in these sites, and are causing decline in their conservation value. Every protected semi-natural grassland should be actively managed by the use of traditional farming practices. These include extensive grazing (by cattle, horses, sheep, etc.) or regular hand mowing followed by sward removal (at least once or twice a year).
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