Revision of Partulidae (Gastropoda, Stylommatophora) of Palau, with description of a new genus for an unusual ground-dwelling species

By

Slapcinsky, John
Kraus, Fred

Type

Article

Date of Publication

2016

Original Publication

ZooKeys

Volume

614

Pages

27-49

Subjects

land snail , new species , Oceania , Pacific , Palaopartula , Partula , pulmonate

Contributed by

Pensoft Publishers

Language

English

Published by

Sofia, Bulgaria Pensoft Publishers

Identifiers

DOI: https://doi.org/10.3897/zookeys.614.8807

 

Abstract

We describe a new stylommatophoran land snail of the family Partulidae from Palau. The new species has a combination of morphological and ecological characters that do not allow its placement in any existing partulid genus, so we describe a new genus for it. The new genus is characterized by a large (18–23 mm) obese-pupoid shell; smooth protoconch; teleoconch with weak and inconsistent, progressively stronger, striae; last half of body whorl not extending beyond the penultimate whorl; widely expanded and reflexed peristome; relatively long penis, with longitudinal pilasters that fuse apically into a fleshy ridge that divides the main chamber from a small apical chamber; and vas deferens entering and penial-retractor muscle attaching at the apex of the penis. Unlike all other partulids, the new species is strictly associated with rocks in contact with the ground. Comparing the other three Palauan species – currently assigned to Partula – to our new genus and to other partulids makes it clear that they require their own genus because their morphology is quite different from that of true Partula and from that of all other genera. Hence, we resurrect the name Palaopartula Pilsbry for these snails.