chiton Nuttallochiton mirandus

Nuttallochiton mirandus is found throughout Antarctica and the Antarctic Peninsula, South Shetland Islands, South Sandwich Islands, Bouvet Island, Falkland Islands, and Burdwood Bank from depths of 67 to 761+ meters [1,2,4,8,10,11,12]. On its upper surface, N. mirandus has eight overlapping valves (plates) surrounded by a tough brownish-tinted girdle; the valves are colored creamy white, with reddish brown flecks [10,11,12]. Some of the valves of N. mirandus may be colored red or reddish-brown [1,3,5,11,12]. The length of N. mirandus specimens range up to twelve centimeters [2,5].

Chitons use their large foot for movement and clinging; there is a groove containing gills on either side of the foot. Chitons have a file-like radula mouthpart used in feeding; the radula of Nuttallochiton mirandus is hard and hooked for destroying bryozoan colonies [7]. N. mirandus swallows big bryozoan pieces up to 6 - 7 millimeters long [7]. One study found N. mirandus with its gut content almost entirely bryozoans; foraminiferans were also ingested while grazing on other food items [6]. Another study found N. mirandus with its gut content 70-100% bryozoans, 20-25% greenish mass, and 5% sand and foraminiferans [7].

Males and females of N. mirandus spawn synchronously, with the posterior of their bodies bent upward into the water column, releasing sperm and eggs [9].

Taxonomic Note: Genus Nuttallochiton spelled with two L's [1].

1: Monograph of Living Chitons. Volume 3. P Kaas & RA Van Belle. Leiden: EJ Brill, 1985; 2: Archiv fur Molluskenkunde 122:171-187, 1993; 3: Discovery Reports. Volume 33. Issued by the National Institute of Oceanography. Cambridge : University Press, 1966. pp.95-250; 4: Antarctic Mollusca : with Special Reference to the Fauna of the Ross Sea. RK Dell. Wellington, NZ : Royal Society of New Zealand, 1990. Bulletin 27, Royal Society of New Zealand; 5: Australasian Antarctic Expedition 1911-1914. Scientific Reports. Series C, Zoology and Botany. Volume 4, Part 1. Mollusca. Sydney : David Harold Paisley, 1916; 6: Antarctic Journal of the United States 11(1):24-26, 1976; 7: Berichte zur Polarforschung, Reports on Polar Research 249:62-65, 1997; 8: Polar Biology 20(4):229-247, 1998; 9: Weddell Sea Ecology : Results of EPOS, European "Polarstern" Study. G Hempel, ed. New York : Springer Verlag, 1993. pp. 303-311; 10: Chitons of the World : an Illustrated Synopsis of Recent Polyplacophora. FJA Slieker. Cupra Marittima, Italy : Mostra Mondiale Malacologia ; Ancona, Italy : L'informatore Piceno, 2000. pp. 44-45; 11: Moluscos Magallanicos : Guia de los Moluscos de la Patagonia y del Sur de Chile. DO Forcelli. Buenos Aires, Argentina : Vazquez Mazzini, 2000; 12: Mollusques Amphineures et Gasteropodes. A Vayssiere. Deuxieme Expedition Antarctique Francaise (1908-1910) Commandee par le Dr Jean Charcot. Paris : Masson et Cie, 1917

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