The tree snail on Rota Island, Northern Mariana Islands, long identified as Partula gibba (Partulidae), is a different species

By

Sischo, David
Hadfield, Michael G.‏ (Michael Gale)

Type

Article

Date of Publication

2021

Original Publication

ZooKeys

Volume

1037

Pages

105--118

Subjects

cryptic species , Mariana Islands , Micronesia , Mollusca , narrow-range endemic , systematics

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.1037.56303

 

Abstract

Tree snails in the family Partulidae are widespread across the tropical Pacific, with endemic species occurring on most high islands. Partulid species have faced catastrophic range reductions and extinctions due primarily to introduced predators. Consequently, most extant species are threatened with imminent extinction. The U.S. administered Mariana Islands, consisting of Guam in the South and the Commonwealth of the Northern Mariana Islands (CNMI) in the north, historically harbored six endemic partulid species, half of which are thought to be extinct. While conducting a phylogenetic assessment of Partula gibba, an extant tree-snail with a range spanning at least seven islands within the archipelago, it was discovered that what has been identified as P. gibba on the island of Rota is a misidentified cryptic species. Here we use molecular phylogenetics, shell morphometrics and reproductive anatomy to describe it as a new species, Partula lutaensissp. nov.. Because the new species has suffered population declines and has a restricted range, consisting solely of the small island of Rota, we highlight the urgent need for conservation measures.