Assessment Rationale:

Cerodontha bistrigata is an endemic species of the Azores (Azores, Portugal), being present historically at least on Corvo, Faial, Pico, S. Jorge and Terceira islands. This species has been found in wet and boggy areas or in vegetation near water bodies. From the historical data, this species has a relatively small extent of occurrence (EOO = 12,364 km2 ) and limited area of occupancy (AOO = 104 km2 ). It is possible that this species has declined in the past, e.g. as a result of the invasion of non-native plants, however, 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, the species is assessed as Near Threatened. Conservation/restoration of native wet and boggy areas, as well as invasive species control could potentially aid this species conservation. 

Geographic Range:

Cerodontha bistrigata is an Azorean-endemic species that was described from the islands of Corvo, Faial, Pico, S. Jorge and Terceira (Azores, Portugal) (Borges et al. 2010). Based on the historical data (Frey 1945), the Extent of Ooccurrence (EOO) could be ca. 12,364 km² and the Area of Occupancy (AOO) could be ca. 104 km². However, there is no recent information regarding the distribution of this species. 

Population:

No current population size estimates exist for this species. Current Population Trend: Unknown. 

Habitat and Ecology

The ecology and traits of this species are unknown. Agromyzidae larvae are phytophagous, being, in general, leaf miners, with some species being stem or seed miners. The larvae have a high degree of host specificity. Several species attack plants of agricultural value and are considered pests. Adults occur in a variety of habitats, being dependent on the larvae host plants. Cerodontha bistrigata specimens have been mainly collected in wet and boggy areas, or on grassy ground near water bodies. Systems: Terrestrial.

Major Threat(s):

A lack of information regarding the present status of this species precludes an assessment of potential threats. Nevertheless, the ecology of other members of the Agromyzidae family and the likely habitat preferences of this species suggests that the plant hosts of Cerodontha bistrigata larvae (and consequently this species), might be affected by future habitat declines as a consequence of climate change (Ferreira et al., 2016), increased droughts and invasive plant species. Past human disturbance and land use changes might have also affected this species, but further ecological data are required.

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 wet and boggy areas, as well as invasive species control could potentially aid this species' conservation. Historically at least, this species was present in areas that are currently included in the Natural Parks of Corvo, Faial, Pico and Terceira.