Species

BackMinicia floresensis Wunderlich, 1992

Minicia floresensis Wunderlich, 1992

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Arachnida
  • Order: Araneae
  • Family: Linyphiidae
VU Vulnerable
IUCN Red List Status:

Countries of Occurrence:
Portugal - Azores

Archipelago(s):
Azores

Reviewer/s:
Russell, N.

Contributor/s:
Mendonca, E. & Lamelas-López, L.

Facilitators / Compilers/s:


Assessment Rationale:

Minicia floresensis is an endemic money spider species occurring on five islands of the Azorean archipelago (Azores, Portugal) (Flores, Pico, S. Jorge, Terceira and S. Miguel) (Borges et al. 2010). It has an Extent of Occurrence (EOO) of ca. 20,000-20,598 km² and a small Area of Occupancy (AOO) of 152- 224 km². The species is only abundant in very pristine sites (e.g. sites with a high habitat quality index sensu Gaspar et al. 2011) and is rare in most sites. Currently an invasive plant, Hedychium gardnerianum, is impacting some of the areas where this species occurs, decreasing the quality of the habitat. Based on Ferreira et al. (2016) the habitat will further decline as a consequence of climate change. Based upon the inferred decline in AOO, the decline in the quality and structure of habitat in some islands and number of locations the species is assessed as Vulnerable (VU). We suggest as future measures of conservation: (1) regular monitoring of the species; and (2) control of invasive species namely Hedychium gardnerianum.

Geographic Range:

Minicia floresensis is an endemic money spider species occurring on five islands of the Azorean archipelago (Azores, Portugal) (Flores, Pico, S. Jorge, Terceira and S. Miguel) (Borges et al. 2010). Within these five islands it is known from thirteen Natural Forest Reserves: Caldeiras Funda e Rasa and Morro Alto e Pico da Sé (Natural Park of Flores); Mistério da Prainha, Caveiro and Caiado (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 and Pico da Vara (Natural Park of S. Miguel). The Extent of Occurrence (EOO) is ca. 20,000-20,598 km2 and the estimated Area of Occupancy (AOO) is 152-224 km2 .

Regions:
Portugal - Azores
Extent of Occurrence (EOO):
20,000-20,598 (km2)
Area of Occupancy (AOO):
152-224 (km2)
Elevation Lower Limit:
700 (m)
Elevation Upper Limit:
1092 (m)
Biogeographic Realms:
Palearctic
Presence:
Extant
Origin:
Endemic Azores
Seasonality:
Resident

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 is rare in most sites. Despite the fact that Minicia floresensis has been recorded between 340 and 1,092 m elevation, the species is particularly abundant only between 700 and 1,092 m. Many of the known sites are currently being invaded by invasive plants (e.g. Hedychium gardnerianum), and 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 340 and 1,092 m elevation, Minicia floresensis is particularly abundant only between 700 and 1,092 m in very pristine sites (see Gaspar et al. 2011). This species builds its typical sheet-webs in association with herbaceous vegetation and is particularly abundant in Calluna vulgaris. It is frequent in open spaces in forest, high elevation small patches of natural grasslands and bogs. Systems: Terrestrial.

Major Threat(s):

In the past, the species has probably strongly declined due to changes in habitat size and quality (Triantis et al. 2010). 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 and 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 and S. Jorge island without control by the Conservation Managers) is also occurring. 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 several regionally protected areas (Natural Parks of Flores, Pico, São Jorge, Terceira and S. Miguel). Degraded areas, degraded due to invasive plant species, should be restored and a strategy needs to be developed to address the current threats posed by invasive species and trampling by dairy cattle, as well the future threat of climate change. Formal education and awareness are needed to allow future investments in restored habitats invaded by invasive plants and to ensure better management of cows. Additionally, further research is needed into its ecology and life history in order to find additional specimens in other areas of native habitats and obtain adequate information on population size, distribution and trends. 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).