sea spider Colossendeis australis

Colossendeis australis is found throughout Antarctica and the Antarctic Peninsula, South Shetland Islands, South Sandwich Islands, South Georgia Island, Falkland Islands, Kerguelen Island, New Zealand, and Southeast Pacific and Southwest Atlantic Basins off Chile and Argentina from depths of 15 to 3,935 meters [1,2,3,4,7]. C. australis has relatively short propodal claws and a leg span about 25 centimeters [1,4].

The Colossendeis sea spiders are mostly giant deep-sea species though some Antarctic species live in shallow depths [1,4]. The Colossendeis sea spiders are the largest sea spiders with some having leg spans as wide as fifty centimeters and trunks of five centimeters or more [1,4].

A closer view of Colossendeis australis. The large downcurved proboscis is characteristic of C. australis; there is one other species with such a bulbous curved proboscis, but its proboscis is longer and has almost a lip on its dorsal surface [1,5].

Antarctic and subantarctic sea spiders comprise 251 species, representing 21.5% of worldwide species, with 101 species endemic to Antarctica and 60 endemic to subantarctic areas [6]. Sea spiders are also called pycnogonids. Sea spiders are exclusively marine and mostly bottom dwelling (benthic) [4]. Adult sea spiders either suck the juices from soft-bodied invertebrates or browse on hydroids and bryozoans. Male sea spiders carry cemented egg clutches gathered from females until hatching and often after hatching in the larval stages [4]. Since sea spider larvae are not planktonic, sea spider dispersal is slow and intermittent leading to the development of many endemic species among shallow-water sea spiders [4].

1: Antarctic and Subantarctic Pycnogonida : Nymphonidae, Colossendeidae, Rhynchothoraxidae, Pycnogonidae, Endeididae, and Callipallenidae. CA Child Antarctic Research Series Volume 69, Biology of the Antarctic Seas 24. Washington DC : American Geophysical Union, 1995; 2: US National Museum Polar Invertebrate Catalog at www.nmnh.si.edu/iz/usap/usapdb.html; 3: Tethys Supplement 4:135-156, 1972; 4: Marine Fauna of New Zealand: Pycnogonida (Sea Spiders). CA Child.. Wellington : National Institute of Water and Atmospheric Research, 1998. NIWA Biodiversity Memoir 109; 5: C Allan Child, personal communication, 2002; 6: Polar Biology 24:941-945, 2001; 7: Antarctic Science 13(2):144-149, 2001

Identification provided by C Allan Child. Text ©Peter Brueggeman. Photograph ©Norbert Wu. Photograph may not be used in any form without the express written permission of Norbert Wu. Norbert Wu no longer grants permission for uncompensated use of his photos under any circumstances whatsoever; want more info?