BackTrixoscelis proxima Séguy, 1936

Trixoscelis proxima Séguy, 1936


  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Diptera
  • Family: Trixoscelididae
DD Data Deficient
IUCN Red List Status:

Countries of Occurrence:
Portugal - Azores


Russell, N.


Facilitators / Compilers/s:

Assessment Rationale:

Trixoscelis proxima is an endemic species of the Azores (Portugal), known from a single disturbed site on S. Miguel island. From the historical data, this species could have a very small Extent of Occurrence (8 km2) and Area of Occupancy (8 km2), and it is possible that this species has declined in the past as a result of human activity. The present situation of this species needs to be further assessed, and further research is needed into its population, distribution, threats, ecology and life history. Conservation/restoration of native vegetation, as well as invasive species control could also potentially aid this species' conservation. Based upon the lack of recent data regarding this species' population, distribution, threats and ecology, this species is assessed as Data Deficient (DD).

Geographic Range:

Trixoscelis proxima is an Azorean-endemic species that was described from a single site (Furnas) on S. Miguel island (Azores, Portugal) (Borges et al. 2010), which currently is highly disturbed. Based on the old historical data (Séguy 1936), the Extent of Occurrence (EOO) would be ca. 8 km² and the Area of Occupancy (AOO) would be ca. 8 km². However, there is no recent information regarding the distribution of this species.

Portugal - Azores
Extent of Occurrence (EOO):
Area of Occupancy (AOO):
Elevation Lower Limit:
200 (m)
Elevation Upper Limit:
400 (m)
Biogeographic Realms:
Endemic Azores


No current population size estimates exist for this species.

Habitat and Ecology

The ecology and traits of this species are unknown. Little is known of the ecology and life history of the Trixoscelididae and the immatures are unknown (McAlpine et al. 1987). Species of this family are widely distributed through the Mediterranean Basin and Mongolian Highlands (and the Paleartic in general), being apparently adapted to warm semi-arid sand dunes, grasslands or shrubby areas, in association with some flowers and various other plants (Woźnica 2007). Trixocelis proxima specimens were collected in an area with hot springs, and lakes and rivulets of geothermal origin.

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 only one highly disturbed site (Furnas) with high human activity, and where major historical land use changes took place, might imply that this species is being affected by habitat degradation. Invasive species might also contribute to the habitat degradation. Based on Ferreira et al. (2016), habitat declines as a consequence of climate change might also affect this species. Additionally, given that this species was only recorded from a area of hot springs, future violent geothermal activity may also compromise this species

Conservation Actions

The species is not protected by regional law. The present situation of this species needs to be further assessed, and further research is needed into its population, distribution, threats, ecology and life history. From what is known of habitat its preferences, conservation of native forest and vegetation, and invasive species control could potentially aid this species' conservation. Historically, this species was present in one area that is currently highly disturbed, but included in the Natural Park of S. Miguel.