Matthew's pinwheel snail

For #BiodiversityMonth we’re featuring some of the interesting, weird and wonderful species that live in or visit Norfolk Island National Park and Botanic Garden that we don't usually turn the spotlight on!

Matthew's pinwheel snail (Penescosta mathewsi) is a tiny snail with a golden-brown, ribbed shell of only 2.2 mm in diameter

Pinwheel snails are one of Australia’s most speciose groups, with hundreds of endemic species, but many are still undescribed. P. mathewsi, like most pinwheel snails, live in leaf litter, and are small to minute in size, with flattened, discoidal shells covered in a delicate pattern of ribs

 In order to find these tiny snails, the Australian Museum researchers and #TeamSnail need to collect bags of leaf litter, sieve it, and sort it under a microscope

Penescosta mathewsi is listed by the IUCN as vulnerable. It is endemic to Norfolk Island, where it is probably now limited to the national park

There are four other species of Penescosta endemic to Norfolk Island, all smaller and rarer than P. mathewsi and never yet collected alive. One of the goals of #TeamSnail's current research is to determine whether these all represent valid species, and whether they are still extant

Credit: Adnan Moussalli, Museums Victoria