Naria turdus

Invasion History

First Non-native North American Tidal Record: 2021
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record: 2021

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General Invasion History:

The  Thrush Cowrie (Naria turdus) is a snail native to the Indian Ocean and Red Sea. It is known from Sri Lanka and Mozambique to the Red Sea coast of Israel and Egypt (Verdcourt 1956; Oleinik et al. 2023). There are scattered records from the West Pacific, including Indonesia and Australia, but specific records are lacking (GBIF 2023; US National Museum of Natural History 2023; Yasser et al. 2023). It apparently traversed the Suez Canal and was collected in the Mediterranean Israel by 1980, and in Port Said, Egypt, by 1997 (Galil et al. 2009). In 2003, it was collected in the Gulf of Gabes, Tunisia (Delongueville and Scaillet 2004), and in 2005, it was found near the island of Lampedusa, in the Strait of Sicily (Castelli 2005). In 2021, shells of Naria turdus were collected on the northwest coast of the Caribbean Island of Aruba and is the first record of this cowrie in the Atlantic Ocean (Dekkers and Ros 2022; Oleinik et al. 2023). Subsequently, records of this cowry were published from 6 more locations in the Caribbean, including Bonaire (2022); Curacao (2022, Dekkers and Ros 2022); Costa Rica (date unknown); Venezuela (date unknown); the Cayman Islands (2023); and Puerto Rico (2021) (Oleinik et al. 2023).  All of the shells were of adult animals, and some had holes indicating predation by octopuses (Dekker and Ros 2022; Leal et al. 2023).

In December of 2022, a live specimen of Naria turdus was was photographed in Lake Worth, Lagoon, Florida, adjacent to the Port of Palm Beach, Florida (Leal et al. 2022). On November 27, 2023, a second specimen was photographed in the Indian River Lagoon in Jupiter, Florida (Alexander Parry, personal communication 2023; https://www.inaturalist.org/observations/192338741). Many subsequent records have confirmed the establishment of this species in southern Florida (Leal 2023).

North American Invasion History:

Invasion History on the East Coast:

In December of 2022, a live specimen of Naria turdus was photographed in Lake Worth Lagoon, Florida, adjacent to the Port of Palm Beach, Florida (Leal et al. 2022).  A second specimen was photographed in the Indian River Lagoon in Jupiter, Florida (Alexander Parry, personal communication 2023, https://www.inaturalist.org/observations/192338741).  This snail was probably introduced by ballast water in the port of Palm Beach (Dekker and Ros 2022; Leal et al. 2023). By late 2023, this snail had been identified from several locations from the Indian River lagoon, and is considered 'Here to Stay' (Leal 2023).

Invasion History Elsewhere in the World:

The  Thrush Cowrie (Naria turdus) is a snail native to the Indian Ocean and Red Sea. It is known from Sri Lanka and Mozambique to the Red Sea coast of Israel and Egypt (Verdcourt 1956; Oleinik et al. 2023). There are scattered records from the West Pacific, including Indonesia and Australia, but specific records are lacking (GBIF 2023; US National Museum of Natural History 2023; Yasser et al. 2023). It apparently traversed the Suez Canal and was collected in the Mediterranean Israel by 1980 and in Port Said, Egypt, by 1997 (Galil et al. 2009). In 2003, it was collected in the Gulf of Gabes, Tunisia (Delongueville and Scaillet 2004), and in 2005, it was found near the island of Lampedusa, in the Strait of Sicily (Castelli 2005). In 2021, shells of Naria turdus were collected on the northwest coast of the Caribbean Island of Aruba, the first record of this cowrie in the Atlantic Ocean (Dekkers and Ros 2022; Oleinik  2023). Subsequently, records of this cowry were published from 6 more locations in the Caribbean, including Bonaire (2022); Curacao (2022, Dekkers and Ros 2022), Costa Rica (date unknown), Venezuela (date unknown), the Cayman Islands (2023), and Puerto Rico (2021).  All of the shells were of adult animals, and some had holes indicating predation by octopuses (Dekker and Ros 2022; Leal et al. 2023).

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Description

The Thrush Cowrie (Naria turdus) has an oval shell, without a visible spiral, and with a ventral aperture along its length. The rim of the aperture is toothed. In the living animal, the mantle covers much of the shell, surrounding the a patch of bare shell with branched papillae resembling a band of algae or hydroids. The dead shell is smooth and glossy, because of continuous secretion of shell material by the mantle (Lewis 2007; US National Museum of Natural History Invertebrate Zoology 2023). The ventral surface of the shell is white, while the dorsal surface is gray, marked with numerous brown spots, A typical size is 30 mm, but some specimens can reach 50 mm (Abbott 1973; Morris 1975; Oleinik, et al. 2023).

 

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Taxonomy

Ecology

General:

The  Thrush Cowrie (Naria turdus) is an herbivorous (but maybe also feeding on sponges) snail, native to tropical marine waters, and occurring on a variety of habitats, including coral reefs, rocky shores, and seagrass beds, at a range of depths from the lower intertidal to 45 m (Zenetos et al. 2003; Castelli 2015; Oleinik 2023; Oleinik et al. 2023).  It has been collected in warm-temperate waters, in the straits of Sicily, in the Mediterranean (Castelli 2005). Many of the shells collected in the Caribbean have bore holes stemming from octopus predation (Oleinik et al. 2023).

Food:

Algae; Sponges

Consumers:

Octopuses, Crabs, Fishes

Competitors:

Native cowries, (e.g., Naria aciclularis, Luria cinerea)

Trophic Status:

Herbivore

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Habitats

General Habitat	Coral reef	None
General Habitat	Mangroves	None
General Habitat	Grass Bed	None
General Habitat	Rocky	None
Salinity Range	Polyhaline	18-30 PSU
Salinity Range	Euhaline	30-40 PSU
Tidal Range	Subtidal	None
Vertical Habitat	Pelagic	None

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Life History

The  Thrush Cowrie (Naria turdus) has separate sexes. Cowries of the genus Naria lay egg capsules, usually attached to a hard substrate, hatching into planktonic veligers (Oleinik et al. 2023). The larval stage duration is unknown (Oleinik 2023; Oleinik et al. 2023).

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Tolerances and Life History Parameters

Minimum Length (mm)	29.5	Specimens from the Caribbean (Oleinik 2023)
Maximum Length (mm)	37.9	Caribbean shells (Oleinik 2023)

General Impacts

The  Thrush Cowrie (Naria turdus) is established in the Caribbean and known from two photographed specimens and several other sightings in Florida. If established there, it could compete with native Atlantic Yellow Cowrie (Naria acicularis) and Atlantic Gray Cowrie (Luria cinerea) (Oleinik 2023; Oleinik et al. 2023). Cowries have been prized by many peoples as currency and ornaments, and by shell collectors.  However, Oleinik et al. (2023) consider deliberate introduction by a collector to be an unlikely vector.

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References

Abbott, R. Tucker (1974) American Seashells, Van Nostrand Reinhold, New York. Pp. <missing location>

Castelli, David Vito (2005) [First report of Cypaea (Erosaria) turdus (Lamarck 1810) in the Scilian Channel, Naturalista Siciliano Ser 4. Volume 24(3-4): 185-186

Dekkers, Aart; Ros, Leo G. (2022) On the Invasion of Naria turdus (Gastropoda, Cypraeidae) in the Dutch Caribbean, with taxonomic notes on the sp, Festivus 54: 269-273

DeLongueville, Christianne; Scaillet, Rolande (2004) Erosaria turdus (Lamarck, 1810) (Gastropoda: Cypraeidae) in the Gulf of Gabès, Tunisie, Novapex 5(4): 147-148

GBIF (Global Biodiversity Information Facility) 2017-2023 GBIF (Global Biodiversity Information Facility). https://www.gbif.org/



Leal, Jose 2022 An Invasive Mollusk Makes Headway in the Caribbean: Where Next?. https://www.shellmuseum.org/post/an-invasive-mollusk-makes-headway-in-the-caribbean-where-next



Leal, Jose H. 2023 Here to stay!. https://www.shellmuseum.org/post/here-to-stay



Lewis, Edwin R. 2007 Cowries- Maui Shells. https://people.eecs.berkeley.edu/~lewis/cowries.html



Morris, Percy A. (1975) A field guide to shells of the Atlantic, Houghton-Mifflin, Boston. Pp. <missing location>

Oleinik, Anton E. (2023) Introduction of Naria turdus (Lamarck 1810) (Gastropod: Cypraeidae) from the western Indian Ocean to the island of Aruba, western Atlantic Ocean, Nautilus 137(1): 24-30

Oleinik, Anton E.; Leal, José H.; DuPont, Anne; Uthairat, Nuch (2023) A prediction held true: first record of the non-indigenous Thrush Cowrie Naria turdus (Lamarck, 1810) (Gastropoda:Cypraeidae) in South Florida, Nautilus 137: 31-34

Smithsonian National Museum of Natural History- Invertebrate Zoology 2023 Cowries. https://naturalhistory.si.edu/research/invertebrate-zoology/news-and-highlights/cowrie



Verdcourt, Nernard (1954) The Cowries of the East African Coast (Kenya, Tanganyika, Zanzibar and Pemba), Journal of the East African Society of Natural History 22: 129-147

WoRMS Editorial Board (2021). 2021 World Register of Marine Species. https://www.marinespecies.org/



Yasser, A. Gh.; Naser, M. D.; ; Abdul-sahib, I. M. (2022) Some new records of marine gastropods from the Iraqi coast, Zoodiversity 56(4): 285-290

Zenetos, Argyro Golani, Dani (2003) CIESM Atlas of Exotic Species in the Mediterranean: Molluscs, CIESM Publishers, <missing place>. Pp. <missing location>

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