Margarella antarctica explained

Margarella antarctica is a species of sea snail, a marine gastropod mollusk in the family Calliostomatidae, the top snails.

Distribution

This marine species occurs off the South Orkney Islands, the South Shetland Islands, the Antarctic Peninsula, and the Bellingshausen Sea.

Description

It is orange-yellow, with two pairs of cephalic tentacles with large black eyes.The shell is small, and wider than it is high.^[1] The orbicular, deeply umbilicated shell has an obtuse-conical shape. It contains four convex whorls, the last of which is adorned only by growth lines. The oblique aperture is sub-circular and pearly inside. In, adults its edges are joined by a callus . The operculum is polygyrous spiral. The color of the shell is bluish gray or greenish.^[2] The maximum recorded shell length is 12.5 mm.^[3]

Habitat

Minimum recorded depth is 0 m.^[3] Maximum recorded depth is 24 m.^[3]

References

• Zelaya D.G. (2004) The genus Margarella Thiele, 1893 (Gastropoda: Trochidae) in the southwestern Atlantic Ocean. The Nautilus 118(3): 112–120
• Engl W. (2012) Shells of Antarctica. Hackenheim: Conchbooks. 402 pp

Notes and References

1. Bouchet, P. (2010). Margarella whiteana Linse, 2002. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=197259 on 2011-03-17
2. https://archive.org/details/expditionantar03char Charcot, Lamy et al. (1906), Expédition antarctique française (1903–1905) fasc. 3 (1906)
3. Welch J. J. (2010). "The "Island Rule" and Deep-Sea Gastropods: Re-Examining the Evidence". PLoS ONE 5(1): e8776. .