Welcome to the IBA
Welcome to the International Bryozoology Association (IBA). We connect researchers from over 40 countries dedicated to the study of Bryozoa. This site is your central resource for association news, upcoming conferences, and information on the phylum Bryozoa.
We update our content regularly with the latest newsletters and research updates. In the meantime, you can find additional resources at bryozoa.net.
Brief History of the IBA
Founded in 1968 by a small group of passionate scientists, the IBA has grown into a global network of over 200 palaeontologists and zoologists. We continue our founding mission to encourage collaborative research and drive the exchange of ideas on Bryozoa.
Every three years, we host an international conference and publish its peer-reviewed proceedings. Thanks to their scientific depth and broad scope, these volumes have become definitive reference works in the field of bryozoology.
What is a bryozoan?
The phylum Bryozoa comprises a distinct group of predominantly colonial invertebrates distributed across virtually all aquatic environments. These colonies consist of interconnected modules known as zooids, which typically measure between 0.5 and 1 mm in length [1]. Each feeding-zooid features a specialized, ciliated tentacular crown (lophophore) which is employed in suspension feeding and can be rapidly retracted into a protective body wall (cystid) [2]. Taxon-specific variations in cystid composition range from unmineralized chitinous structures to heavily biomineralized calcium carbonate matrices [1, 2].
Colonial morphology ranges from encrusting sheet-like formations over diverse hard substrates to erect, branching structures, with some species exhibiting both growth forms [3]. Colonial expansion occurs via the asexual budding of daughter zooids, rendering the colony a aggregate of genetically identical modules [1, 4].
To date, approximately 6,000 extant and over 15,000 fossil species of Bryozoa are recognized, categorized across three primary clades: Phylactolaemata, Stenolaemata, and Gymnolaemata [1, 5]. While the Phylactolaemata are confined to freshwater environments and defined by a distinctive horseshoe-shaped lophophore, both Stenolaemata and Gymnolaemata exhibit circular lophophores and predominantly inhabit marine ecosystems [1]. Ctenostomata, a minor subclade of gymnolaemates, represents the only group distributed across all aquatic regimes. However, the majority of extant bryozoan diversity is concentrated within Cheilostomata, another gymnolaemate order. Cheilostomes are distinguished by extensively calcified body walls and pronounced zooidal polymorphism [6].
If these intriguing animals caught your interest, check out the references below for further reading:
[1] Schwaha, T. (2020). 1 General introduction. In Phylum Bryozoa (pp. 1–10). De Gruyter. https://doi.org/10.1515/9783110586312-001
[2] Mukai, H., Terakado, K., & Reed, C. G. (1997). Bryozoa. In F. W. Harrison & R. M. Woollacott (Eds.), Microscopic anatomy of invertebrates (Vol. 13, pp. 45–206). Wiley-Liss.
[3] Ryland, J. S. (1970). Bryozoans. Hutchinson University Library.
[4] Ostrovsky, A. N. (2020). Sexual reproduction in Bryozoa. In T. Schwaha (Ed.), Handbook of Zoology. Bryozoa (pp. 101–122). de Gruyter.
[5] Bock, P., & Gordon, D. P. (2013). Phylum Bryozoa Ehrenberg, 1831. Zootaxa, 3703, 67–74.
[6] Schwaha, T. (2020). 9 Gymnolaemata. In Phylum Bryozoa (pp. 265–268). De Gruyter. https://doi.org/10.1515/9783110586312-009