IUCN SSC Mid-Atlantic Island Invertebrates Specialist Group

Species

BackMellissius adumbratus Wollaston, 1869

Mellissius adumbratus Wollaston, 1869

Shadowy Chafer (English)

  • Kingdom: Animalia
  • Phylum: Arthropoda
  • Class: Insecta
  • Order: Coleoptera
  • Family: Scarabaeidae
EN Endangered
IUCN Red List Status:

Countries of Occurrence:
Saint Helena - British Overseas Territory

Archipelago(s):
St. Helena

Assessor/s:
Pryce, D. & White, L.

Reviewer/s:
Gerlach, J.

Contributor/s:

Facilitators / Compilers/s:


Assessment Rationale:

This species is only known from four locations at one of which it was only seen in 1931 (Decelle 1972; Ashmole and Ashmole 2003; Mendel, Ashmole and Ashmole 2008); the population appears to be relatively large and stable at two of these. Construction of the new airport at Prospoerous Bay Plain has impacted the easternmost sites at this location and several further sites along the Southern Ridge. Remediation work is planned at the Southern Ridge sites but construction of the airport access road will result in the permanent loss of some habitat and potential further fragmentation. This species has an extent of occurrence (EOO) of 43 km² and an area of occupancy (AOO) of 20 km². It is assessed as Endangered

Geographic Range:

Endemic to St Helena island, in the South Atlantic Ocean, where it is found in the east and south of the island

Regions:
Portugal - Azores
Extent of Occurrence (EOO):
20 (km2)
Area of Occupancy (AOO):
20 (km2)
Elevation Lower Limit:
297 (m)
Elevation Upper Limit:
518 (m)
Biogeographic Realms:
South Atlantic Ocean
Presence:
Extant
Origin:
Endemic St. Helena
Seasonality:
Resident

Population:

This species is currently known from four locations where it is apparently fairly common at three of them. At the Millennium Forest and Blue Point, when planting at the time of year when grubs are easily detectable, one is found in about every tenth tree-planting hole (J. Courtis pers. comm. 2014) While live adults are almost never found, dead specimens are easily located amongst Creeper (Carpobrotus edulis (L.) N.E. Br) at the end of the breeding season

Habitat and Ecology

This species is found in degraded arid areas in the east and south of the island in where Creeper (Carpobrotus edulis (L.) N.E. Br) and Common Saltbush (Atriplex semibaccata R. Br.) are often the dominant vegetation. Endemic Scrubwood (Commidendrum rugosum (Dryland) DC.) bushes are present at two of the locations. The larvae are subterranean where they presumably feed on the roots of plants. Adults are almost never encountered alive so are presumably nocturnal; dead adults persist for some time and the species can be mapped by looking for their dried remains

Major Threat(s):

Habitat destruction has occurred at one of its locations due to construction of the new airport.

Conservation Actions

Any research and monitoring of this species would be of value. Of critical importance is the continued expansion and linking of habitat fragments as well as removal of invasive non-native species where this is possible