scyphomedusa Desmonema glaciale

Desmonema glaciale is found in Antarctica and the Antarctic Peninsula, South Orkney Islands, and South Georgia Island, where it is found near the surface in continental shelf waters [1]. D. glaciale is pink-violet in color and its bell-like umbrella can be over one meter in diameter [1]. D. glaciale has broad curtain-like pleated oral arms [1].

D. glaciale feeds on diverse pelagic and benthic prey including euphausids and fish; it has been observed engulfing benthic animals like Parborlasia corrugatus nemertean worms and Odontaster validus seastars [2].

Gelatinous carnivores are a predominant and sometimes the main component of the macroplankton and nekton community in the Southern Ocean [4]. Gelatinous carnivores are important components of the food web because they are a control mechanism for its structure [5].



Here's Desmonema glaciale at the sea ice edge of McMurdo Sound.

D. glaciale is distinctive for its thick, flattened, cord-like tentacles that are few in number and may be over five meters long [1].

Here's a top view of Desmonema glaciale.

The hyperiid amphipod Hyperia macrocephala can be found riding along on it, living as a juvenile in the medusa's gastrovascular system (where they avoid becoming a food item for the medusa) and becoming a parasite feeding on the epidermis when adult [2,3].

1: Pelagic Scyphomedusae (Scyphozoa: Coronatae and Semaeostomeae) of the Southern Ocean. RJ Larson. Washington, DC: American Geophysical Union, 1986; 2: British Antarctic Survey Bulletin 27:39-49, 1972; 3: Polar Biology 11(1):19-25, 1990; 4: Annales de l'Institut Oceanographique 73(2):139-158, 1997; 5: Annales de l'Institut Oceanographique 73(2):123-124, 1997

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