IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group


BackMelanozetes azoricus Weigmann, 1976

Melanozetes azoricus Weigmann, 1976

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Arachnida
  • Order: Acari: Oribatida
  • Family: Ceratozetidae
NT Near Treatened
IUCN Red List Status:

Countries of Occurrence:
Portugal - Azores


Danielczak, A.


Facilitators / Compilers/s:

Assessment Rationale:

Melanozetes azoricus is an endemic species of the Azores (Portugal), known from the islands of Flores, Faial, Terceira, S. Miguel and Sta. Maria. From the available data, it has a relatively large extent of occurrence (EOO = 33,695 km2 ), but a limited area of occupancy (AOO = 48 km2 ), which is likely an underestimate, as this species probably has a wider distribution through the soil component of the islands. It can be assumed that this species is affected by human activities and invasive plant species that alter the natural structure and composition of the soil; and future climatic changes and increased risk of droughts will also affect this species. The present situation of this species needs to be further assessed and further research is needed into its population, distribution, threats, ecology and life history. However, the AOO of the species is relatively small, on the global scale, and if there were more data available it is possible that the species could qualify as threatened under criterion B2. Therefore, it is assessed as Near Threatened. Conservation of natural habitats and invasive species control could potentially aid this species conservation.

Geographic Range:

Melanozetes azoricus is an Azorean-endemic oribatid mite species known from Flores, Faial, Terceira, S. Miguel and Sta. Maria islands (Azores, Portugal) (Borges et al. 2010), known from a several natural areas. It has been recorded from seven Natural Forest Reserves; Caldeiras Funda e Rasa and Morro Alto e Pico da Sé (Flores), Caldeira do Faial (Faial), Caldeira Sta. Bárbara e Mistérios Negros (Terceira), Graminhais and Pico da Vara (S. Miguel) and Pico Alto (Sta. Maria). From the available data, the Extent of Occurrence (EOO) could be ca. 33,695 km² and the Area of Occupancy (AOO) could be 48 km².

Portugal - Azores
Extent of Occurrence (EOO):
33,695 (km2)
Area of Occupancy (AOO):
48 (km2)
Elevation Lower Limit:
Elevation Upper Limit:
Biogeographic Realms:
Endemic Azores


No current population size estimates exist for this species. This species occurs in natural vegetation areas of several islands, and as an oribatid mite, it is likely common and widespread in the soil habitat. Current Population Trend: Unknown. 

Habitat and Ecology

The ecology and traits of this species are unknown. Oribatid mites are associated with organic matter in most terrestrial ecosystems, being found throughout the soil profile, in surface litter, on grasses, shrubs or in the bark and leaves of trees, among other habitats. Oribatida are also one of the most numerically dominant arthropod groups in the organic horizons of most soils (Behan-Pelletier, 1999). Melanozetes azoricus specimens were collected mainly in native vegetation areas, with several collected from mosses in association with Juniperus brevifolia, or in other native vegetation. Other specimens were collected from under Cryptomeria japonica. Systems: Terrestrial.

Major Threat(s):

A lack of information regarding the present range of this species precludes an assessment of potential threats. Nevertheless, it can be assumed that this species will be affected by future habitat declines as a consequence of climate change (Ferreira et al. 2016) and increased droughts. This species has been found in areas of native vegetation and it can be assumed that factors that degrade habitat quality, in the form of changes in the soil structure and composition, namely land use changes, agricultural practices or invasive plants, might also affect this species.

Conservation Actions

The species is not protected by regional law, but its known habitat is in regionally protected areas (Natural Parks of Flores, Faial, Terceira, S. Miguel and Sta. Maria). Besides climate changes and increased risk of droughts, land-use changes and invasive species are likely one of the main current and future threats faced by this species. As such, conservation of native habitats and invasive species control could potentially aid this species' conservation. Further research is needed into its population, distribution, threats, ecology and life history, and it is necessary to develop a monitoring plan for the invertebrate community in order to contribute to the conservation of this species.