MAIISG

Assessment Rationale:

The Gran Canaria Crested Grasshopper (Dericorys minutus) was originally described from Maspalomas on Gran Canaria, where it has not been recorded again since 1949. Occasional searches during the last years were unsuccessful at this site, so that it is quite likely that the species is regionally extinct in this area. However, it has recently been re-discovered in the north of Gran Canaria. More intense searches are needed to clarify whether the species still occurs elsewhere on the island. The only known remaining subpopulation is highly threatened by construction of houses. Based upon its small extent of occurrence and area of occupancy, its continuing decline on habitat area and number of mature individuals, and the fact that only one location is known, the species is assessed as Critically Endangered (CR). Immediate protection of its habitat as well as research on its ecology and population trend and monitoring of its status is needed.

Geographic Range:

The Gran Canaria Crested Grasshopper is endemic to Gran Canaria (Canary Islands, Spain), from which it is only known from a single locality in the north of the island (Sardina del Norte, near Gáldar), where it was recently rediscovered (H. López pers. comm. 2016). It was originally described from a single specimen found at the beach of Maspalomas (Chopard 1954), where it was never found again. The extent of occurrence (EOO) is between 4 and 10 km², the area of occupancy (AOO) is 4 to 8 km².

Population:

In the south of Gran Canaria, the species has not been found since 1949 and is probably extinct. Recently the species has been rediscovered in the north of the island. As the only known locality is strongly affected by the construction of houses, a continuing decline in the number of mature individuals is inferred.

Habitat and Ecology

The ecology of this species has not been studied. It is likely to prefer coastal open habitats with scarce vegetation, although its habitat preferences are not clear as the species has been only recently re-discovered. Its next relatives are specialised on Chenopodiaceae as food plants.

Major Threat(s):

The species has probably gone extinct near Maspalomas as a consequence of the destruction of its habitat caused by touristic development. The recently discovered second site is threatened by the construction of houses. Based on this threat, the species occurs only at one location.

Conservation Actions

For the recently discovered subpopulation near Sardina del Norte, conservation action needs to be implemented immediately. Particularly, the habitat needs to be protected from further deterioration. Research on its population size, population trend and ecology is urgently needed. Furthermore, a monitoring program needs to be implemented. It also should be studied if the species has survived elsewhere at the coast of Gran Canaria. The species is not present in protected areas.