Practical information to identify and manage non-native, invasive plants and animals
The Quiet Invasion:A Guide to Invasive Species of the Galveston Bay Area
Melanoides tuberculatus
| ITIS TSN: | 71533 |
| Presence: | Species of Concern |
| Habitat: | Aquatic |
| Native Range: | Northern Africa, Australia, and Southern Asia |
Human Health
Red-rimmed melania is an intermediate host for human trematode parasites such as the Chinese lung fluke (Paragonimus westermani).Prohibited Lists
As of 2010, this species is not prohibited by the TPWD.Introduction Pathways
This species was brought into the U.S. in the 1930s for use in aquaria. The earliest introductions of this species were most likely from aquarium releases (Benson 2006). This species has also been spread by inadequate cleaning of scientific equipment (Karatayev et al. 2009).Geographic Distribution
Red-rimmed melania is native to subtropical and tropical regions of Africa, Asia and Australia. In the U.S., populations are established in 15 states. The species has been found in Texas since the 1960s, with established populations found in central, southern and western Texas. The species is not yet established in the Lower Galveston Bay Watershed (Benson 2006).Specific Primary Habitats
The optimal water temperature range for the red-rimmed melania is from 18-32°C. It prefers quiet, eutrophic, shallow, turbid habitats. This snail can tolerate salinities from 0-30 ppt, and low dissolved oxygen levels. This snail is active at night, hiding under decaying plants or stones, and buries itself in mud during the day (UDWR 2010).Ecological, Economic, or Social Impact
M. tuberculatus can reach high densities (up to 10,000 per square meter found in Florida) (Thompson 1984), displacing native gastropods and other detritivores. Red-rimmed melania is an intermediate host for trematode parasites such as the Chinese lung fluke (Paragonimus westermani), which can infect humans. Another trematode, Centrocestus formosanus, parasitizes the gills of the endangered fountain darter (Etheostoma fonticola) (Benson 2006).Physical Description
Red-rimmed melania has an average length of 40 mm, with an elongated spiral, conical, shell featuring 4-5 ribbed whorls. The shell is a mottled light brown color with dark red spots. There is an operculum (a membrane that covers the shell opening when the soft parts of the animal are retracted) present (Benson 2006; UDWR 2010).Reproduction Characteristics
The red-rimmed melania is reproductively mature at a length of 10 mm. Red-rimmed melania reproduce both sexually and asexually via parthenogenesis (reproduction via development of an unfertilized egg). The species gives birth to live young, with the female carrying up to 70 young in a brood pouch attached to the head. Melania young are released from the pouch at 1-2 mm in length (UDWR 2010).Feeding
This species primarily feeds on microalgae and detritus.Control
Early detection is key to preventing the spread and establishment of this species and regional/local monitoring or surveillance is essential. Nonnative snails should not be imported alive or released in local waterways. If found in local waters, note the location and notify the TPWD.Lists
This species belongs to the following lists:
Images
To view a larger version of an image, click on the thumbnail. Red-rim melania (Melanoides tuberculatus). Photo courtesy of Bill Frank, Jacksonville, Florida, www.jaxshells.org, USGS NAS Database. |
 from Devils River, TX.jpg) Red-rim melania (Melanoides tuberculatus) from Devils River, TX. March 2008. Photo courtesy of Lyubov Burlakova. |
 Red-rim melania (Melanoides tuberculatus). Photo courtesy of Stuart Halliday, Wikimedia Commons. |