IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group


BackRachispoda atrolimosa Frey, 1945

Rachispoda atrolimosa Frey, 1945

Lesser dung fly, Small dung fly

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Diptera
NT Near Treatened
IUCN Red List Status:

Countries of Occurrence:
Portugal - Azores


Danielczak, A.


Facilitators / Compilers/s:

Assessment Rationale:

Rachispoda atrolimosa is an endemic species of the Azores (Portugal), known from Flores, S. Jorge, Terceira and S. Miguel islands. From the historical data, this species has a relatively small extent of occurrence (EOO = 15,427 km2) and a small area of occupancy (AOO = 120 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. However, the EOO and AOO of the species are relatively small, on the global scale, and if there were more data available it is possible that the species could qualify as threatened under criterion B. Therefore, it is assessed here as Near Threatened. Conservation of native forests, of natural streams and other water bodies and of coastal areas could potentially aid this species' conservation, together with problematic invasive species control.

Geographic Range:

Rachispoda atrolimosa is an Azorean-endemic species known from the islands of Flores, S. Jorge, Terceira and S. Miguel (Azores, Portugal) (Borges et al. 2010), occurring in several sites of native forest or with bodies of water, some currently highly disturbed. Based on the historical data (Frey 1945), the Extent of Occurrence (EOO) could be ca. 15,427 km² and the Area of Occupancy (AOO) could be ca. 120 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:
0 (m)
Elevation Upper Limit:
600 (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. Sphaeroceridae are commonly associated with all types of organic decay including dung, carrion, fungi, supralittoral seaweed where (they play a major as decomposers), compost, mammal nests, cave debris and small deposits of dead vegetation, but also in man-made habitats, like sewage pipes (McAlpine et al. 1987), having in general an important role in the nutrient cycling, as decomposers. Immature stages are poorly known (McAlpine et al. 1987), but it is most likely that larvae feed on manure, decaying matter, seaweed or fungi. Some species in this group can potentially be considered a nuisance or pests in food production plants (McAlpine et al. 1987). Rachispoda atrolimosa specimens have been collected from native forest, from the vicinity of lakes, streams and hot springs and from coastal areas.

Major Threat(s):

A lack of information regarding the present status of this species precludes an assessment of potential threats. Nevertheless, the habitats where this species has been collected suggests that it might be affected by future habitat declines as a consequence of climate change (Ferreira et al. 2016) and increased droughts. Also, some sites where this species was collected (Furnas and Lagoa das Sete Cidades) are currently highly disturbed by human activity and by habitat degradation caused by invasive species. Praia da Vitória (Terceira) waterfront is currently also highly urbanised and industrialised. Past human disturbance and land use changes might have also affected 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 its habitat preferences, conservation of native forests, of coastal areas and of natural streams and water bodies, together with invasive species control, could potentially aid this species' conservation. Historically at least, this species was present in one area that is currently highly disturbed, but included in the Natural Park of S. Miguel.