Assessment Rationale:

Neon acoreensis is a salticid spider species occurring on seven islands of the Azorean archipelago (Azores, Portugal) (only absent from Graciosa and Corvo) (Borges et al. 2010). It has a large Extent of Occurrence (EOO = ca. 37,107 km²), but a relatively small Area of Occupancy (AOO = 112-220 km²). The species is only present in very pristine sites (e.g. sites with a high habitat quality index sensu Gaspar et al. 2011) and it is rare at most sites. Currently an invasive plant, Hedychium gardnerianum, is changing some of the areas and decreasing the quality of the habitat. Based on Ferreira et al. (2016) the habitat will further decline as a consequence of climate change. As such the number of locations could be small (10 or 11, depending on the full extent of the species on S. Miguel). The species is precautionarily listed as Vulnerable, but further research is required. We suggest as future measures of conservation: (1) regular monitoring of the species; and (2) control of invasive species namely Hedychium gardnerianum.

Geographic Range:

Neon acoreensis is a jumping spider species occurring on seven islands of the Azorean archipelago (Azores, Portugal) (only absent in Graciosa and Corvo) (Borges et al. 2010). Within these seven islands it is known from twelve Natural Forest Reserves: Caldeiras Funda e Rasa and Morro Alto e Pico da Sé (Natural Park of Flores); Cabeço do Fogo (Natural Park of Faial); Mistério da Prainha and Caveiro (Natural Park of Pico); Pico Pinheiro and Topo (Natural Park of S. Jorge); Biscoito da Ferraria, Pico Galhardo, Caldeira Sta. Bárbara e Mistérios Negros and Terra Brava (Natural Park of Terceira); Graminhais (Natural Park of S. Miguel) and Pico Alto (Natural Park of S. Maria). The Extent of Occurrence (EOO) is ca. 37,107 km2 and the Area of Occupancy (AOO) is 112-220 km2 .

Population:

The species is only abundant in very pristine sites (e.g. sites with a high habitat quality index sensu Gaspar et al. 2011) and rare at most sites. Despite the fact that Neon acoreensis has been recorded between 320 and 1,051 m elevation, the species is particularly abundant only between 700 and 1,051 m. Many of the known sites are currently being invaded by invasive plants (e.g. Hedychium gardnerianum) or degraded by uncontroled cattle trampling in some native shrub grasslslands. A continuing decline in the number of mature individuals is inferred from monitoring schemes (Borges et al. 2016) and from the ongoing habitat degradation. Current Population Trend: Decreasing.

Habitat and Ecology

Despite the fact that this species has been recorded between 320 and 1,051 m elevation, Neon acoreensis is particularly abundant only between 700 and 1,051 m in very pristine sites (see Gaspar et al. 2011). This species lives in the ground, and is associated with herbaceous vegetation, but can also be found in the canopies of several endemic trees. It is frequent in open spaces in forest. Systems: Terrestrial.

Major Threat(s):

Currently, the rapid advance and expansion of invasive plants species is the major threat (particularly Hedychium gardnerianum), which is changing the structure of the forest and natural grasslands, as well as the cover of bryophytes and ferns in the soil, which will impact the species' habitat quality. Ongoing soil erosion due to trampling by dairy cattle (cattle are entering the native areas in Flores, Pico and S. Jorge island without control by the Conservation Managers) is another threat. Based on Ferreira et al.(2016) the habitat will further decline as a consequence of climate change (increasing number of droughts, and habitat shifting and alteration). 

Conservation Actions

The species is not protected by regional law, but its habitat is in regionally protected areas (Natural Parks of Faial, Flores, Pico, S. Jorge, Terceira, S. Miguel and S. Maria). Degraded habitats on some islands, degraded due to invasive plant species, should be restored (e.g. S. Maria) and a strategy needs to be developed to address the current threat from invasive species in all islands, and the future threat by climate change. The management of cows entering native areas in some islands is also critical. A habitat management plan is needed and one is anticipated for the coming years. Formal education and awareness are needed to allow future investments in restored habitats invaded by invasive plants; while further research is needed into its ecology and life history in order to obtain adequate information on population size, distribution and trends, particularly on S. Miguel. An area-based management plan is also necessary for the most disturbed sites including invertebrate monitoring to contribute to a potential species recovery plan. Monitoring every ten years using the BALA protocol will inform about habitat quality (see e.g. Gaspar et al. 2011).