Do marine sponges host epizoic tardigrades?

Authors:Paul J. Bartels, Diane R. Nelson


Just over 200 species of marine tardigrades have been described, and most of these have been collected in sand and other sediments. However, several species are known to associate with other invertebrates such as barnacles, bryozoans, and holothurians. It is possible that many epizoic tardigrade species remain to be discovered, since surveys of tardigrades on other potential animal hosts are very rare. Sponges, with extensive cavities, constant water flow, and protective secondary compounds, are known to harbour a highly diverse epizoic community, but there are no published studies indicating that marine tardigrades are among this community, and there is only one published record of tardigrades from freshwater sponges. We collected 30 samples of marine sponges, consisting of 12 species, from the central Bahamas. We processed these for tardigrades and other meiofauna using the freshwater shock technique. One unusual non-tardigrade in our samples was Loxosomella sp., an entoproct which is a known commensal on sponges. Here we also provide the first record of marine tardigrades associated with marine sponges. However, we found only one species, Archechiniscus bahamensis, which is the most common species occurring free-living in Bahamian subtidal sand. Therefore, we conclude that marine sponges, at least in the Bahamas, do host epizoic marine tardigrades, but they may not be a unique or important host for marine tardigrades.

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Bartels, P. J., J. J. Apodaca, C. Mora, and D. R. Nelson. 2016. A global biodiversity estimate of a poorly known taxon: Phylum Tardigrada. Zoological Journal of the Linnean Society 178: 730–736. doi:10.1111/zoj.12441

Bartels, P. J., P. Fontoura, and D. R. Nelson. 2018. Marine tardigrades of the Bahamas with the description of two new species and updated keys to the species of Anisonyches and Archechiniscus. Zootaxa 4420: 43–70.

Bartels, P. J., Ł. Kaczmarek, M. Roszkowska, and D. R. Nelson. 2015. Interactive map of marine tardigrades of the world.

Bell, J. 2008. The functional roles of marine sponges. Estuarine Coastal and Shelf Science 79: 341–353. doi:10.1016/j.ecss.2008.05.002

Boltruszko, J. and J. Ejsmont-Karabin. 2013. Epizoic communities of Rotifera inhabiting sponges in freshwaters of north-eastern Poland. Oceanological and Hydrobiological Studies 42: 46–50. doi: 10.2478/s13545-013-0062-2

Degma, P. and R. Guidetti. 2007. Notes to the current checklist of Tardigrada. Zootaxa 1579: 41–53.

Degma, P., R. Bertolani, and R. Guidetti. 2009–2017. Actual checklist of Tardigrada species (2009–2017, 33nd Edition:13-10-2017).

Fontoura, P., P. J. Bartels, A. Jørgensen, R. M. Kristensen, and J. G. Hansen. 2017. A dichotomous key to the genera of the marine heterotardigrades (Tardigrada). Zootaxa 429: 1–45.

Guidetti, R. and R. Bertolani. 2005. Tardigrade taxonomy: an updated checklist of the taxa and a list of characters for their identification. Zootaxa 845: 1–46.

Kaczmarek, Ł., P. J. Bartels, M. Roszkowska, and D. R. Nelson. 2015. The zoogeography of marine Tardigrada. Zootaxa 4037: 1–189.

Kristensen, R. M. and R. P. Higgins. 1984. A new family of Arthrotardigrada (Tardigrada: Heterotardigrada) from the Atlantic coast of Florida, U.S.A. Transactions of the American Microscopical Society 103: 295–311. doi. 10.2307/3226191

Nielsen, C. 1964. Studies on Danish Entoprocta. Ophelia 1: 1–76.

Ribeiro, S. M., E. O. Omena, and G. Muricy. 2003. Macrofauna associated to Mycale microsigmatosa (Porifera, Demospongiae) in Rio de Janeiro State, SE Brazil. Estuarine Coastal and Shelf Science 57: 951–959. doi:10.1016/S0272-7714(02)00425-0

Rützler, K. 1976. Ecology of Tunisian commercial sponges. Tethys 7: 249–264.

Tałanda, J. and K. Zawierucha. 2017. First record of water bears (Tardigrada) from sponges (Porifera). Turkish Journal of Zoology 41: 161–163. doi.10.3906/zoo-1510-4

Voultsiadou-Koukoura, E., A. Koukouras, and A. Eleftheriou. 1987. Macrofauna associated with the sponge Verongia aerophoba in the north Aegean Sea. Estuarine Coastal and Shelf Science 24: 265–278.

Webster, N. S., A. P. Negri, M. H. G. Murray, M. M. H. G. Munro, and C. N. Battershill. 2004. Diverse microbial communities inhabit Antarctic sponges. Environmental Microbiology 6: 288–300. doi:10.1111/j.1462-2920.2004.00570.x

Wiedenmayer, F. 1977. Shallow-water sponges of the western Bahamas. Basel: Birkhauser Verlag.

Wulff, J. L. 2006. Ecological interactions of marine sponges. Canadian Journal of Zoology 84: 146–166. doi:10.1139/z06-019

Zea, S., T. P. Henkel, and J. R. Pawlik. 2014. The sponge guide: a picture guide to Caribbean sponges, 3rd edition.


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