''Monterissa gowerensis'', also known as the Lord Howe microturban, is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

of small cave

snail A snail is a shelled gastropod. The name is most often applied to land snails, terrestrial molluscs, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gas ...

s with an operculum,

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

s in the family

Hydrocenidae Hydrocenidae is a taxonomic family of minute land snails or cave snails with an operculum, terrestrial gastropod mollusks or micromollusks in the clade Cycloneritimorpha. Hydrocenidae are widespread across the Palearctis and Africa, but reach ...

Description

The globosely turbinate shell of adult snails is 2.1–2.4 mm in height, with a diameter of 1.7–2 mm, with deeply impressed sutures. It is smooth, glossy and pale golden-brown in colour. The

umbilicus Umbilicus may refer to: *The navel or belly button *Umbilicus (mollusc), a feature of gastropod, Nautilus and Ammonite shell anatomy *Umbilicus (plant), ''Umbilicus'' (plant), a genus of over ninety species of perennial flowering plants *Umbilicus ...

is closed. The ovately lunate aperture has an operculum.

Distribution and habitat

This terrestrial and freshwater species occurs on

Australia Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...

Lord Howe Island Lord Howe Island (; formerly Lord Howe's Island) is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies directly east of mainland Port ...

in the

Tasman Sea The Tasman Sea is a marginal sea of the South Pacific Ocean, situated between Australia and New Zealand. It measures about across and about from north to south. The sea was named after the Dutch explorer Abel Janszoon Tasman, who in 1642 wa ...

, where it is rare and found mainly on the slopes of

Mount Gower Mount Gower (also known as Big Hill), is the highest mountain on Australia's subtropical Lord Howe Island in the Tasman Sea. With a height of above sea level, and a relatively flat summit plateau, it stands at the southern end of Lord Howe, jus ...

and

Mount Lidgbird Mount Lidgbird, also Mount Ledgbird and Big Hill, is located in the southern section of Lord Howe Island, just north of Mount Gower, from which it is separated by the saddle at the head of Erskine Valley, and has its peak at above sea level. ...

in leaf litter and cliff crevices.

References

Hydrocenidae Gastropods of Lord Howe Island Vulnerable fauna of Australia Gastropods described in 1944 Taxonomy articles created by Polbot Taxa named by Tom Iredale {{Neritimorpha-stub