Largest tenebrionid beetle

Known colloquially as darkling beetles, the tenebrionids constitute a major taxonomic family of beetles containing more than 20,000 species. These include such familiar forms as the mealworm beetle (its larvae are mealworms), the red flour beetle and the destructive flour beetle, as well as a spectacular flightless species called the Frigate Island giant beetle Polposipus herculeanus. The largest tenebrionid species – and principally arboreal despite being unable to fly – this very sturdy, unmistakeable beetle grows up to 3 cm long (1.18 in), its abdomen is covered in horny tubercles, and it is entirely confined to Frégate (Frigate) Island in the Seychelles, as a result of which it is officially classified as Vulnerable by the IUCN. Previously, it was classed as Critically Endangered owing to the presence of introduced rats on Frégate, but these have now been successfully eradicated here. An estimated 54,351 of these beetles currently exist, confined entirely to an area of just 2 square km (0.77 square miles).

There are a few captive populations of this very rare species in existence, too, the largest being at London Zoo, UK. These have been established specifically for conservation purposes, with the ultimate aim being to reintroduce specimens back into the wild, possibly onto additional Seychelles islands where this species may have existed in earlier times (it once existed on Round Island, Mauritius, but is now extinct there).

It can live up to seven years in captivity, but its normal life-span is roughly half of that.