Assessment Rationale:

Geostiba melanocephala is a single island endemic species from S. Miguel (Azores, Portugal) (Borges et al.2010). It has a very small extent of occurrence (EOO = 0-4 km²) and area of occupancy (AOO = 0-4 km²). The species may occur only at one location and is possibly extinct (not recorded since 1876). Therefore, it is assessed as Critically Endangered (Possibly Extinct).

Geographic Range:

Geostiba melanocephala is a single island endemic species from S. Miguel (Azores, Portugal) (Borges et al. 2010). This species is very rare and possibly it is near extinction.

Population:

The species is only known from a single subpopulation. A continuing decline in the number of mature individuals is inferred from historical records.

Habitat and Ecology

The species occurred in the native forest of São Miguel Island (Azores), but it is considered possibly extinct. This is a nocturnal predator. The current altitudinal range is unknown.

Major Threat(s):

In the past, the species has probably strongly declined due to changes in habitat size. In the last 50 years additional major changes occurred with pasture intensification and the spread of the invasive plant Hedychium gardnerianum. Based on Ferreira et al. (2016) the habitat will further decline as a consequence of climate change (increasing number of droughts and habitat shifting & alteration).

Conservation Actions

The species is not protected by regional law. Its habitat is possibly in a regionally protected area (Natural Park of São Miguel Island). Further research is needed into its ecology and life history in order to find extant specimens.