The diversity of Hawaiian land snails was once extraordinary, both in terms of the number of species and the unparalleled levels of endemism. Habitat loss and the establishment of non-native species that prey on native snails have resulted in catastrophic declines in Hawaii's native land snails in the last century, and many are now critically endangered or extinct. Despite these losses, some species persist, and recent surveys have identified remnant populations of several species previously thought extinct. To effectively manage these remaining taxa and to understand what has been lost, the systematics of the land snail fauna of Hawaii needs revision; this will facilitate accurate identification of threatened species, discovery of undescribed species, and a fuller understanding of native land snail evolution and conservation. The development of type catalogs for all major museum collections holding type material of Hawaiian land snails is a necessary first step in this revisionary process. Here we describe the type material at the Paleontological Research Institute (PRI) in Ithaca, New York. Most of the type collection of Hawaiian land snails at PRI was acquired from Wesley Newcomb through the Cornell Museum. Newcomb described 126 species and varieties of endemic Hawaiian land snails, of which the PRI Hawaiian land snail collection contains type material for 74 nominal species-group taxa belonging to the Achatinellidae and Amastridae. Eighteen of these are recognized as primary type material (i.e., syntypes or lectotypes, there are no holotypes or neotypes).

Terrestrial gastropods are important herbivores, prey, and as decomposers in woodlands of the Midwestern USA. Vegetation structure and composition are dynamic and may influence gastropod abundance and distribution, but relationships among gastropod communities and environmental variables are understudied. We burned three treatment units in an oak-hickory woodland during 2004 and conducted additional burns on two of those treatment units, one in 2014 and the other in 2015. In May and August 2016, we collected leaf litter containing gastropods from transects within these three burn treatment units and used 19 environmental variables that were potentially important to gastropods. Environmental variables were associated with herbaceous and woody vegetation, ground cover, physiography, and burn history. We identified 14 species of gastropods at the study site. No significant environmental models were found for gastropod abundance, richness, effective number of species (based on Shannon entropy), or effective number of species (based on the Gini-Simpson index). Statistically significant associations among gastropods and environmental variables were seen in three species. Euchemotrema leaii was associated with areas having low coverage of shrubs and other perennials, and abundant leaf litter, whereas Neohelix alleni was positively associated with leaf litter and was abundant in areas with low total cover. Glyphyalinia indentata was associated with higher elevation transects, may be impacted by recent burning, and was found in areas with greater amounts of grasses and vines.

Pupoidopsis hawaiensis Pilsbry & C.M. Cooke, 1921, and its monospecific genus, is the only representative of Pupillidae in tropical Pacific Islands. Although most of native species from that region are single island endemics, P. hawaiensis has been recorded from Hawaii to the Tuamotus. However, it has not been recorded alive since 1965. Here we report the only modern living population of that species from a single site in Anaa (Tuamotu archipelago). A single COI haplotype and a single 28S allele support the hypothesis of self-fertilization. The species should be listed as Critically Endangered, and included in the list of protected species of French Polynesia. An Action Plan for its conservation should be undertaken, with protection status given to its last known stronghold in Anaa.

Warrana besnardi (Klappenbach, 1963) is the single Atlantic species of the genus, and part of the family Condylocardiidae, composed of 21 genera and about 150 species. Recent availability of many well-preserved specimens allowed us to perform a detailed study of the shell of this species, using scanning electron microscopy and descriptions of the hinge structure, the larval shell, and the inner surface, complimenting and expanding previous taxonomic work. This morphological assessment included very small (0.5 mm in length), young individuals and larger (up to 1.5 mm in length), fully developed animals. Key new observations include the outline of the valves that varies with growth, with the young individuals being more equilateral, while the adults are obliquely inequilateral. The inner surface of the valves has microscopic pores, a feature already observed for other condylocardiids (but not for the Cuninae). The larval shell has the prodissoconch I (pI) averaging 220 µm in length, and the prodissoconch II (pII) 259 µm, measurements which suggest lecithotrophic development and that W. besnardi probably broods its young.

Albino land snails are rare in the wild. Here we report finding an individual Euhadra quaesita quaesita (Deshayes, 1850) showing total albinism. In contrast to the mosaic of dark and light-brown bumps on the soft body of wild-type E. quaesita quaesita, the soft body of the albino individual was white or pale yellow, except for the head wart. We hypothesize the color of the head wart is derived from sex hormones as melanin pigments were lost in head-wart epithelial cells. Finding an albino E. quaesita quaesita opens opportunities for multiple new lines of inquiry.

Boettgerilla pallens Simroth, 1912 is reported in Oregon for the first time and has been collected in five counties. Species identification was confirmed using distinctive morphological characters (i.e. dark keel running from the end of the mantle to the tail; posterior end of the mantle pointed and not rounded; body cylindrical, hump shaped when at rest; and slender and worm-like when crawling) and partial mitochondrial cytochrome C oxidase subunit I (COI) sequences from three specimens. Information on the general biology, ecology and pest status of the species are presented.

Ridleyconcha Christensen, gen. nov., is proposed as a replacement for RidleyaAncey, 1901 (Mollusca: Scolodontidae), a junior homonym of RidleyaDelage & Hérouard, 1899 (Porifera: Polymastiidae). Ridleyconcha is a monotypic species of land snails inhabiting the Fernando de Noronha Archipelago, Brazil; its sole species is Ridleyconcha quinquelirata (E.A. Smith, 1890), new combination.