The perks of being endolithic

Abstract

AB Aquatic Biology Contact the journal Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections AB 17:1-5 (2012) - DOI: https://doi.org/10.3354/ab00473 FEATURE ARTICLE: NOTE The perks of being endolithic Christine Hanna Lydia Schönberg1,*, Max Wisshak2 1Australian Institute of Marine Science at the University of Western Australia, Crawley, WA 9006, Australia 2Senckenberg am Meer, Marine Research Department, 26382 Wilhelmshaven, Germany *Email: c.schoenberg@aims.gov.au ABSTRACT: Bioeroding sponges erode and live in calcium carbonate substrates such as coral. The most obvious reason for this lifestyle is shelter from grazers and predators, but this has never been conclusively shown. To investigate this we collected Siphonodictyon mucosum Bergquist, 1965 and Cliothosa aurivillii (Lindgren, 1898), 2 lesser-studied bioeroding sponges common in coral rock at Orpheus Island, central Great Barrier Reef, Australia. During sampling we broke up blocks of dead coral that contained the sponges and observed post-fracture healing processes. Even though both sponges produce large erosion chambers and their endolithic tissue is soft and easily ruptured, they initially displayed early signs of healing, showing some scarring after only 3 to 4 days. However, endolithic tissue of S. mucosum specimens exposed to direct sunlight did not continue to heal, but rotted away, while shaded tissue fully healed, toughened and turned brown-black like the external fistules. Likewise, endolithic tissue of C. aurivillii showed signs of healing by contracting, toughening and flattening, but after about 2 wk, some C. aurivillii showed signs of healing nevertheless began to rot and had patches of orange sediment underneath them. Their undersides were teeming with copepods. A closer investigation revealed that the copepods had orange stomach contents the colour of the sponge tissue and produced rust-coloured faeces collecting underneath the sponges. Hence, being endolithic has multiple sheltering functions beyond the obvious escape from grazers and predators, very likely including shading, shielding from parasites and disease, and saving on maintenance costs. KEY WORDS: Siphonodictyon · Cliothosa · Macroendoliths · Healing · Disease · Parasitism Full text in pdf format Information about this Feature Article NextCite this article as: Schönberg CHL, Wisshak M (2012) The perks of being endolithic. Aquat Biol 17:1-5. https://doi.org/10.3354/ab00473 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in AB Vol. 17, No. 1. Online publication date: October 04, 2012 Print ISSN: 1864-7782; Online ISSN: 1864-7790 Copyright © 2012 Inter-Research.