Frade Cave Spider (Anapistula ataecina)

Mohamed bin Zayed Species project number 152511159

Ecology and conservation of the critically endangered Frade Cave Spider (Anapistula ataecina)

In spite of relatively intensive searches, this species is known only from five caves in the Frade Cave System, Sesimbra, Portugal. It has an estimated extent of occurrence (EOO) of less than 3 km2 and an area of occupancy (AOO) around 1km2. It is the only representative of the family Symphytognathidae in Europe and the smallest European spider with adult females measuring 0.5mm. The species occurs inside a Nature Park but it is not adequately protected. Limestone quarries prevail in the area and these expand mostly without environmental impact assessment studies prior to their exploitation. Approximately 20% of the cave system where the species is found has already been destroyed by nearby quarries.

The global aim of this project is to increase knowledge on the spider's current distribution and population trends and propose the legal protection of the species and its habitat.

As objectives, we propose:

1. Distribution and population assessment. The entire karstic region where the species is known to occur (from Espichel to Risco) will be sampled during a full year, bimonthly for each of 20 caves, including the 5 caves where the species is known to live.

2. Biotic interactions. We will sample the associated fauna, so that positive or negative interactions with other species are quantified.

3. Abiotic requirements. Using dataloggers we will measure humidity and temperature inside and outside caves during the sampling year.

4. Scientific publications. We intend to publish two scientific papers in international journals with impact factor.

5. Public outreach. The species will be featured in a photography book about the Frade Cave System as one of the flagship species of the region.

6. Legal protection of species. We will propose its inclusion in national legislation targeting endangered species in need of conservation.

7. Legal protection of sites. We will propose specific legal measures towards the protection of the caves where the species is found to occur.