Invasion HistoryFirst Non-native North American Tidal Record:
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record:
General Invasion History:
The ark shell Anadara satowi is native to the Northwest Pacific, ranging from Hong Kong, China to Hokkaido, Japan (Huang 2001; Academy of Natural Sciences of Philadelphia 2010; Museum of Comparative Zoology 2010).
North American Invasion History:
Invasion History on the West Coast:
In the Northeast Pacific, A. satowi is known only from an empty shell found in Quilcene, Washington, in the Hood Canal (Puget Sound), near the Washington State Shellfish Laboratory. The shell could have been discarded from the laboratory, or else introduced with plantings of Pacific Oysters (Crassostrea gigas) from Japan (Hanna, 1966, cited by Carlton 1979).
Anadara satowi, an ark shell, is a marine bivalve with a thick, strongly ribbed shell. The hinge line bears numerous teeth, arranged in a line on both valves. Both valves have prominent beaks which almost come into contact. The shell is heart-shaped in a side view. Ark shells can occasionally attach to rocks and shells with byssus threads (genus characteristics, Morris 1975). The shell superficially resembles that of A. ovalis in photographs, and is covered with brown periostracum, but may reach a larger size (90+ mm) (Natural History Museum Rotterdam, http://www.nmr-pics.nl/Arcidae_new2/album/index.html). Anadara satowi, like A. ovalis, has hemoglobin in its blood, and has red blood and tissues (Ohnoki et al. 1973).
Scapharca satowi (Dunker, 1882)
Potentially Misidentified Species
Anadara satowi an ark shell, is a suspension-feeding marine bivalve found in muddy, subtidal environments (http://shellauction.net/auction_shell.php?id=645754&pres=1). It may occasionally attach to rocks and shells with byssus threads.
|General Habitat||Unstructured Bottom||None|
|General Habitat||Oyster Reef||None|
|Salinity Range||Polyhaline||18-30 PSU|
|Salinity Range||Euhaline||30-40 PSU|
Tolerances and Life History Parameters
|Broad Temperature Range||None||Cold temperate-Warm temperate|
|Broad Salinity Range||None||Polyhaline-Euhaline|
General ImpactsAnadara satowi, an ark shell, is known as an introduced species only from a single dead shell on the West Coast, and has had no known impacts outside its native range.
Regional Distribution Map
|Bioregion||Region Name||Year||Invasion Status||Population Status|
|NEP-III||Alaskan panhandle to N. of Puget Sound||1966||Def||Failed|
References2002-2016a Malacology Collection Search. http://clade.ansp.org/malacology/collections/
2006-2014b OBIS Indo-Pacific Molluscan Database. http://data.acnatsci.org/obis/
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>
2008-2021 Museum of Comparative Zoology Collections database- Malacology Collection. http://www.mcz.harvard.edu/collections/searchcollections.html
Huang, Zongguo (Ed.) (2001) <missing title>, Krieger, Malabar, FL. Pp. <missing location>
Morris, Percy A. (1975) A field guide to shells of the Atlantic, Houghton-Mifflin, Boston. Pp. <missing location>
Ohnoki, Shiro; Mitomi, Yoshitada; Hata, Ryuichiro; Satake, Kazuo (1973) Heterogeneity of hemoglobin from arca (Anadara satowi,/i>) molecular weights and oxygen equilibria of Arca Hb I and II, Journal of Biochemistry 73(4): 717-725