Assessment Rationale:

Falbouria acorensis is an Azorean-endemic species known from recent records from S. Miguel island, but with an historical distribution that encompassed other islands in the Azores archipelago, from which it potentially has disappeared. From the recent data, this species has a small Extent of Occurrence (343 km2) and Area of Occupancy (56 km2). Further research is needed into its known population, distribution, threats, ecology and life history; and this should include further surveys in its historical range needs in order to confirm whether it has disappeared throughout much of its range or not. Given the high levels of uncertainty over its current range, and the large levels of uncertainty over key parameters, this species is assessed as Data Deficient. Conservation of native forests, natural streams and other humid areas could potentially aid this species' conservation.

Geographic Range:

Falbouria acorensis is an Azorean-endemic species present in S. Miguel island (Capellari and Amorim 2012) (Azores, Portugal). According to historical data, this species was also present on Flores, Faial, Pico and S. Jorge islands (see Capellari and Amorim, 2012), but no recent information exists for these islands. Based on the recent data, the Extent of Occurrence (EOO) could be ca. 343 km² and the Area of Occupancy (AOO) could be ca. 56 km².

Population:

There are no available data on the population size and trend of this species. One can assume at least a certain degree of stability in the population on S. Miguel island, as it was found in similar sites both in 1938 and 2006. However, this species was also historically present on Flores, Faial, Pico and S. Jorge islands (see Capellari and Amorim, 2012), but no recent information exists for these islands. Therefore, it is possible that is has undergone large declines on these islands, but it is not certain over what timeframe. Current Population Trend: Unknown.

Habitat and Ecology

The ecology and traits of this species are unknown. Adults and most larvae of other species of Dolichopodidae are predators, feeding on other arthropods, with the adults of some species being notable predators of Culicidae (McAlpine et al. 1987). The larvae occupy a wide range of habitats, living generally in moist environments such as soil, moist sand, or rotting organic matter. The larvae pupate in cocoons made of cemented soil particles. Dolichopodidae in general inhabit lightly shaded areas near swamps and streams, or in meadows and woodlands (McAlpine et al. 1987). This species has been collected from the undergrowth of native and production forest, from meadows, riverine vegetation and from refuse heaps in the forest, in disturbed sites. Systems: Terrestrial.

Major Threat(s):

A lack of complete information regarding the distribution and population status of this species precludes a full assessment of potential threats. Nevertheless, the presence of this species in some areas highly disturbed by human presence, where major historical land use changes took place like Lagoa das Sete Cidades, might imply that this species is being affected by habitat degradation. Based on Ferreira et al. (2016), habitat declines as a consequence of climate change and increased droughts might also affect this species. 

Conservation Actions

The species is not protected by regional law. Further research is needed into its known population, distribution, threats, ecology and life history; and this should include further surveys in its historical range needs in order to confirm whether it has disappeared throughout much of its range or not. From what is known of its habitat preferences, conservation of native forest, natural streams and other water bodies and other wet areas could potentially aid this species' conservation. This species is present in one highly disturbed area that is included in the Natural Park of S. Miguel.