Tarebia granifera
A small conical freshwater snail with a distinctly bumpy, quilted shell and an all-female population that reproduces without males, established as an invasive species across Florida's warm freshwater springs and slow-moving canals.
A small conical freshwater snail with a distinctly bumpy, quilted shell and an all-female population that reproduces without males, established as an invasive species across Florida's warm freshwater springs and slow-moving canals. It belongs to Thiaridae, the same family as the Malaysian Trumpet Snail already living in the Freshwater Lake, and the two species are sometimes confused in casual observation. No dedicated observation records have been found for Quilted Melania in the miniBIOTA observation records.
Tarebia granifera is native to South and Southeast Asia and tropical Pacific islands, where it inhabits warm freshwater streams, springs, and slow-moving rivers. It has established invasive populations across Florida, Hawaii, the Caribbean, and other subtropical regions through the aquarium and pond trade. In Florida, it is among the most commonly encountered invasive freshwater snails in natural springs systems, including Silver Springs, Rainbow Springs, and the Ichetucknee River.
The shell is conical and elongated, reaching 1.5 to 3 centimeters in length, with a pointed apex and a body whorl bearing distinct rows of rounded tubercles. Shell color varies from pale tan to dark brown or gray, often with subtle banding. The aperture is oval and relatively narrow.
Invasive populations of Tarebia granifera in Florida and Hawaii consist almost entirely of females that reproduce through apomictic parthenogenesis, a form of asexual reproduction in which eggs develop without fertilization. The species is ovoviviparous, brooding embryos internally and giving birth to fully formed juvenile snails rather than laying eggs. A single female can establish a new population; no males are required.
Quilted Melania grazes surface biofilm, algae, and microbial films from rocks, glass, and hard substrates. It is primarily a surface grazer rather than a sediment burrower, distinguishing its feeding role from the Malaysian Trumpet Snail, which burrows into substrate to process sediment.
In the Freshwater Lake, Quilted Melania occupies a surface-grazing niche alongside the Seminole Ramshorn Snail, Bladder Snail, and Freshwater Limpet. By grazing biofilm and algae from glass walls and hard surfaces, it helps limit surface fouling and recycles microbial biomass into animal tissue.
In natural Florida spring systems, Quilted Melania populations can reach very high densities and may compete with native snail species for surface-grazing habitat. Whether similar density dynamics play out in the Freshwater Lake is unknown without a population count.
Slough Crayfish is the dominant macroinvertebrate in the Freshwater Lake and is a probable predator of small snails; no direct predation event on Quilted Melania has been recorded.
Introduction context: No introduction event is on record. Introduction method, source, and date of first introduction are all not documented. Quilted Melania is a common hitchhiker on aquatic plants and in mixed snail shipments; it is also sometimes purchased intentionally as an algae grazer for freshwater systems. The most probable route is introduction with another freshwater species or plant.
No dedicated observation records have been found for Quilted Melania in the miniBIOTA observation records. The species is assigned to the Freshwater Lake biome; no introduction date, source, or method is on file. Whether the species is currently established, at what density, or whether it has reproduced in miniBIOTA is unresolved.
Primary Consumer. Grazes biofilm, algae, and microbial films from hard surfaces in the Freshwater Lake, including glass walls, rocks, and substrate particles. Surface-grazing role is distinct from Malaysian Trumpet Snail, which burrows in the sediment. No direct feeding observation has been recorded in miniBIOTA; the grazing role is inferred from thiarid biology.
Florida-invasive species; tolerates a wide range of temperatures in warm freshwater; most commonly found in springs and slow-moving water 20 to 30 degrees Celsius. Tolerant of moderate water quality variation. Specific tolerance thresholds for the Freshwater Lake conditions are unknown.
Florida invasive populations are typically all-female and reproduce parthenogenetically without males; embryos are brooded internally and juveniles are born as fully formed small snails. High reproductive potential from a single founding individual.
Follow this species across the habitats where it currently appears in the miniBIOTA biosphere.
