Monodonta labio

Invasion History

First Non-native North American Tidal Record:
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record:

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General Invasion History:

Monodonta labio is a marine snail with a wide Indo-Pacific distribution, from Madagascar and the Persian Gulf to northern Australia, the Yellow Sea, China, and south-central Japan (Huang 2001; Iijima 2001; Australian Biological Resources Study 2007; Academy of Natural Sciences of Philadelphia 2013). It was found on newly transplanted Pacific oysters in Samish Bay, Washington by Kincaid in 1947 (cited by Hanna 1966 and Carlton 1979), but a population did not become established. To our knowledge, there are no further reports of this snail outside its native range.

North American Invasion History:

Invasion History on the West Coast:

Monodonta labio was reported to be abundant on newly transplanted oysters in Samish Bay, Washington by Kincaid in 1947 (cited by Hanna 1966; Carlton 1979), but a population did not become established. There are no further records of this snail in North American waters.

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Description

Monodonta labio is a medium-sized marine snail, with a thick, conical, turban-like shell, sculpted with strong spiral ridges which are broken up into lines of rounded knobs. The body whorl is somewhat swollen, while the previous (penultimate) whorl is less so. The whorls have a rounded keel. The apex is sharp, but it softened or worn away in adults. The columella has a large blunt tooth, projecting into the aperture, while the inner edge of the outer lip is lined by rounded knobs. The lining of the interior of the aperture is nacreous. The color of the exterior of the shell is reddish brown, dark brown, or pale brown, marked with spiral dashes of white, cream, or pink. Adult snails reach 25-40 mm long. Characteristic habitats include the rocky areas of the lower intertidal, shallow subtidal and subtidal regions. Description from Iijima 2001, Australian Biological Resources Study (2007), and Appeltans et al. 2013.

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Taxonomy

Ecology

General:

Monodonta labio is a marine snail found in rocky intertidal and shallow subtidal regions. Sexes are separate and this snail reproduces by broadcast spawning, with planktotrophic development (Takada 1996). Females mature at about 6-10 mm, at around 1 year of age (Takada 1996, Iijima 2001). Monodonta labio grazes on microalgae in the intertidal and shallow subtidal zones of rocky shores and coral reefs (Takada 1996).

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Habitats

General Habitat	Oyster Reef	None
General Habitat	Rocky	None
General Habitat	Mangroves	None
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Tidal Range	Low Intertidal	None
Tidal Range	Mid Intertidal	None
Vertical Habitat	Epibenthic	None

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Tolerances and Life History Parameters

Minimum Length (mm)	6	Size at maturation, Japan (Takada 1996)
Maximum Length (mm)	30	Australian Biological Resources Study 2007
Broad Temperature Range	None	Warm-temperate-Tropical
Broad Salinity Range	None	Polyhaline-Euhaline

General Impacts

Monodonta labio is not established in North American waters and has no reported impacts.

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References

Academy of Natural Sciences of Philadelphia 2002-2024a Malacology Collection Search. <missing URL>



Academy of Natural Sciences of Philadelphia 2006-2014b OBIS Indo-Pacific Molluscan Database. <missing URL>



Appeltans, W. et al. 2011-2015 World Registry of Marine Species. <missing URL>



Australian Biological Resources Study 2007 Species Bank <i>Monodonta labio</i>. <missing URL>



Carlton, James T. (1979) History, biogeography, and ecology of the introduced marine and estuarine invertebrates of the Pacific Coast of North America., Ph.D. dissertation, University of California, Davis. Pp. 1-904

Hanna, G. Dallas (1966) Introduced mollusks of Western North America, Occasional Papers of the California Academy of Sciences 48: <missing location>

Harvard Museum of Comparative Zoology 2008-2021 Museum of Comparative Zoology Collections database- Malacology Collection. <missing URL>



Huang, Zongguo (Ed.), Junda Lin (Translator) (2001) Marine Species and Their Distributions in China's Seas, Krieger, Malabar, FL. Pp. <missing location>

Iijima, Akiko (2001) Growth of the intertidal snail, Monodonta labio (Gastropoda, Prosobranchia) on the Pacific Coast of central Japan, Bulletin of Marine Science 68(1): 27-36

Takada, Yoshitake (1996) Vertical migration during the life history of the intertidal gastropod Monodonta labio on a boulder shore, Marine Ecological Progress Series 130: 117-123

Takada, Yoshitake (1996) Vertical variation in fecundity of the intertidal gastropod Monodonta labio caused by different growth rates between tidal zones, Ecological Research 11: 371-379

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. http://collections.nmnh.si.edu/search/iz/

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