- Proposed
- Under Assessment
- Preliminary Assessed
- Assessed
- ENPublished
Abstoma purpureum (Lloyd) G. Cunn.
- Scientific name
- Abstoma purpureum
- Author
- (Lloyd) G. Cunn.
- Common names
- IUCN Specialist Group
Mushroom, Bracket and Puffball- Kingdom
- Fungi
- Phylum
- Basidiomycota
- Class
- Agaricomycetes
- Order
- Agaricales
- Family
- Agaricaceae
- Assessment status
- Published
- Assessment date
- 2019-07-23
- IUCN Red List Category
- EN
- IUCN Red List Criteria
- D
- Assessors
- Cooper, J.A.
- Reviewers
- Mueller, G.M.
Assessment Notes
Justification
Abstoma purpureum is a New Zealand very rare endemic thick-skinned, sand-dune saprotrophic puffball. Intact sand-dunes un-impacted by invasive species are uncommon in New Zealand. It has only been reported from seven records at three sites over the period 1920 to 1949. The known sites are severely fragmented, with two known populations, one around Levin in North Island, and the other at Karitane in South Island. Despite extensive searches, there are no confirmed records for 70 years. The type of sand dune habitat where it has been recorded is subjected to an ongoing decline of quality and quantity. The quality and area of habitat has declined significantly in 50 years.The species is assessed as Endangered under D due to a very small and restricted population. The number of mature individuals is estimated as 0-750, with a best estimate of 225. However we note that there are no confirmed records for 70 years and the species may be extinct.
Taxonomic notes
Abstoma purpureum is a New Zealand endemic thick-skinned, saprotrophic sand-dune puffball. The white golf-ball sized fruitbodies are noticeable. Australian records under the name Abstoma purpureum are likely to be misidentifications of Abstoma reticulatum. The only deposited sequence of Abstoma purpureum from the USA, 1923 is a misidentification of a Mycenastrum.Geographic range
Abstoma purpureum is endemic to and only reliably recorded from New Zealand.Population and Trends
Abstoma purpureum has only been recorded from 3 sand-dune sites (coastal and inland) in New Zealand, with the most recent record from 1949. An unverified record from 1981 has been excluded. Larger fungi in New Zealand have been surveyed extensively during annual week-long fungal forays since 1986, and more recently though the engagement of 2,500 observers of 50,000 fungal records as part of the iNaturalist NZ Citizen Science platform. In addition, the puffballs have been actively surveyed by New Zealand mycologists Ross Beever and Jerry Cooper over a period of 20 years. No records have been made, despite visits to likely sand-dune sites during the fruiting season. It is currently unknown if the species still occurs in the known sites, or whether these sites are under specific threat, but in general all natural sand-dunes systems in New Zealand have suffered significant decline/change with no indication that this has been arrested. The population of any species specific to these habitats will therefore continue to decline accordingly. The absence of records suggest a very restricted distribution and our estimates therefore include only the verified sites.
As this is a highly detectable species (conspicuous with a durable sporocarp) which has not been recorded for over 70 years, it is possible that the species is already extinct. The lower estimate of population size is therefore zero. There may be 50 suitable sand dune sites at which it could potentially occur, and each site would be expected to represent up to 15 mature individuals (3 functional individuals), therefore the upper estimate is 750, but it is thought that it is more likely to occupy fewer than all 50 suitable sites, with a more realistic estimate being 15 i.e. 225 mature individuals.
Population Trend: decreasing
Habitat and Ecology
Abstoma purpureum is a saprophtrophic puffball specific to sand-dunes.Threats
Abstoma purpureum is under threat from: 1) decline in sand dunes due to land-use change, 2) invasion and vegetation change by exotic species, especially Ammophila arenaria , 3) climate change and increased storm events impacting on coastal erosion, 4) increased recreational use of beeches. All records for functional individuals fall within land areas classified as Category 1: <10% pre-colonisation indigenous cover remaining (Walker S, Cieraad E, Barringer J 2015. The Threatened Environment Classification for New Zealand 2012: a guide for users. Landcare Research Report LC2184). New Zealand sand-dunes have decreased by 30% in the period 1970-2008 (http://archive.stats.govt.nz/browse_for_stats/environment/environmental-reporting-series/environmental-indicators/Home/Land/sand-dune-extent.aspx).Conservation Actions
Awareness of known sites needs improving so they are considered in any planning and consent processing, and in existing dune restoration and weed management activities.Surveys are required to confirm the presence of the species at historic sites, and any potential new sites. The species (and the genus) require genetic characterisation.
