partulids

Partulidae is a family of tropical land snails that breathe air and live on land. They are native to Pacific islands, with the greatest diversity in Polynesia, including Tahiti, Moorea, Bora Bora, Raiatea, and other Society Islands, as well as in Samoa and nearby archipelagos. The family comprises several genera, most notably Partula and Samoana, though taxonomy has been clarified and revised by modern studies.

Ecology and morphology: Partulids are typically arboreal, inhabiting leaves, twigs, and bark in moist tropical forests, though some species occur in leaf litter or rocky habitats. They are small to moderately sized snails with elongated, often finely patterned shells that can vary in color and sculpture among species. Their activity is strongly tied to humidity and availability of shelter from desiccation.

Reproduction and diet: Like many land snails, partulids are hermaphroditic and reproduce by laying eggs. They feed mainly on microalgae, fungi, lichens, and decaying plant material scraped from surfaces, contributing to nutrient cycling in their ecosystems.

Conservation and significance: Partulids have suffered dramatic declines due to habitat loss, invasive pests, and, most famously, predation by the Rosy Wolf Snail Euglandina rosea introduced in many areas to control other snails. This has led to extinctions in the wild and the near disappearance of several species, with conservation efforts focusing on captive breeding, reintroduction into predator-free refuges, and habitat protection.

Evolutionary importance: The radiation of Partula and related genera on Pacific islands has made partulids a classic model for studying adaptive radiation and speciation in isolated ecosystems. Their decline has limited opportunities for such research, underscoring the impact of introduced species on island biodiversity.