MAIISG

Assessment Rationale:

Neomariania scriptella is an endemic species present in Pico, Graciosa and Terceira islands (Azores, Portugal) (Borges et al. 2010). It has a relatively large extent of occurrence (EOO = ca 3,400 km²), but a small area of occupancy (AOO = 48 km²). Currently Neomariania scriptella is under threat due to degradation of the habitat by urban development and agriculture, but also due to invasive plants Pittosporum undulatum and Hedychium gardnerianum that are 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. Based upon the small area of occupancy, decreasing quality of the habitat and low number of subpopulations it is assessed as Endangered.

Geographic Range:

Neomariania scriptella is an endemic species present in Pico, Graciosa and Terceira islands (Azores, Portugal) (Borges et al. 2010), known from native forest and in open landscapes with isolated tree groups. The extent of occurrence (EOO) is ca 3,400 km² and the maximum estimated area of occupancy (AOO) is 48 km².

Population:

Neomariania scriptella is low abundant in three Central Azorean islands (Pico, Graciosa and Terceira), occurring mostly in highly modified native vegetation but also in naturalised plants.

Habitat and Ecology

The species was originally associated with native forest areas but also in open landscapes with isolated tree groups. The vegetation in those sites is currently highly modified. Possibly, the larvae feed on fruit and flowers such as Fabaceae and Moraceae, also in sporangia of ferns; the adult flies in June (Rebel 1940). Altitudinal range: 10-500 m.

Major Threat(s):

In the past, the species has probably strongly declined due to changes in habitat size and quality, mostly the creation of pastures (Triantis et al. 2010). Currently several threats are operating: i) urban development; ii) agriculture; iii) invasive plants Pittosporum undulatum and Hedychium gardnerianum are changing some of the areas and decreasing the quality of the habitat. These changes are decreasing the relative cover of endemic plants and changing the soil cover (decreasing the cover of bryophytes and ferns). 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 in regionally protected areas (Natural Park of Graciosa). Further research is needed to monitor the species and conservation measures to control the invasive Hedychium gardnerianum and Pittosporum undulatum should be implemented to improve habitat quality for this species. Additional research is needed into its ecology and life history in order to find extant specimens. Degraded habitats should be restored and a strategy needs to be developed to address the future threat by climate change. It is necessary a monitoring plan for the invertebrate community in the habitat in order to contribute to the conservation of this species. A habitat management plan is needed and anticipated to be developed during the coming years. Monitoring every ten years using the BALA protocol will inform about habitat quality (see e.g. Gaspar et al. 2010).