Deep Water Polymastiidae (Porifera, Polymastiida) from the South West Pacific Author Ekins, Merrick Queensland Museum, PO Box 3300, South Brisbane 4101, Brisbane, Queensland, Australia & School of Biological Sciences, University of Queensland, St Lucia, Queensland, 4072 Australia & Griffith Institute for Drug Discovery, Griffith University, Brisbane 4111, Queensland, Australia Author Erpenbeck, Dirk GeoBio-Center, Ludwig-Maximilians-Universität M ¸ nchen, Richard-Wagner-Strasse 10, 80333 Munich, Germany & Dept. of Earth and Environmental Sciences Ludwig-Maximilians-Universität M ¸ nchen, Richard-Wagner-Strasse 10, 80333 Munich, Germany Author Wörheide, Gert 0000-0002-6380-7421 GeoBio-Center, Ludwig-Maximilians-Universität M ¸ nchen, Richard-Wagner-Strasse 10, 80333 Munich, Germany & Dept. of Earth and Environmental Sciences Ludwig-Maximilians-Universität M ¸ nchen, Richard-Wagner-Strasse 10, 80333 Munich, Germany & SNSB - Bayerische Staatssammlung f ¸ r Paläontologie und Geologie, Richard-Wagner-Str. 10, 80333 M ¸ nchen, Germany woerheide @ lmu. de; https: // orcid. org / 0000 - 0002 - 6380 - 7421 woerheide@lmu.de Author Hooper, John N. A. Queensland Museum, PO Box 3300, South Brisbane 4101, Brisbane, Queensland, Australia & Griffith Institute for Drug Discovery, Griffith University, Brisbane 4111, Queensland, Australia text Zootaxa 2023 2023-11-08 5369 1 57 88 https://www.mapress.com/zt/article/download/zootaxa.5369.1.3/52229 journal article 10.11646/zootaxa.5369.1.3 1175-5326 10146837 F906AFDC-DA4E-4ADB-9835-BC4B7692F1FD Tentorium Vosmaer, 1887 Diagnosis: Polymastiidae with columnar or globular growth form protected by a dense cylindrical sheath of longitudinally placed spicules which form a solid imperforate layer. The ectosomal skeleton contains bundles of smaller spicules arranged in a palisade and is limited to the upper surface of the cylinder. Ostia are present on the upper surface. The oscule at the top of a small papilla is on centre of the upper surface. Megascleres are subtylostyles and tylostyles ( Boury-Esnault 2002 ).