Surface Microornamentation of Demosponge Sterraster Spicules, Phylogenetic and Paleontological Implications

ACKNOWLEDGEMENTS I am very grateful to Ana Riesgo and Vasiliki Koutsouveli (NHM London) for sharing SEM pictures from a cryofractured G. barretti and to A. Riesgo for help with fishing the 28S sequences of G. atlantica and G. phlegraei in transcriptomes. I would like to thank Consuelo Sandino for giving access to the NHM paleontology collections. Thanks to Fayez Ahmad (The Hashemite University, Zarqa, Jordan) for sharing two Geoditesia jordanensis specimens; thanks to Christian Marshall (Station Marine d'Endoume, Marseille, France) for his help with the preparation of this specimen. Thanks to Marzia Bo (Università degli Studi di Genova, Italy), Sadie Mills, and Michelle Kelly (NIWA, New Zealand), Nicole de Voogd (Naturalis, Leiden, The Netherlands), Shirley Pomponi (HBOI, Fort Pierce, FL, U.S.A.), and Pilar Ríos (IEO, Gijón, Spain) for collecting and/or sharing the material. Thanks to Klaus Rützler, Sophie Carteron, Jean Vacelet, Pilar Ríos, Rob van Soest, Patricia Gómez/Diana Ugalde for sharing SEM pictures of Geodia, Erylus or Placospongia species which were used for the plates or Table 3. Thanks to all the Institutes where I was able to do SEM images throughout these last 12 years: University of Bergen (Norway), MNHN (Paris, France), IMBE (Station Marine d'Endoume, Marseille, France), and Uppsala University (Sweden). Thanks to David Rees (University of Bergen, BIO) for help sequencing the COI of some of these species. Thanks to Andrzej Pisera (Institute of Paleobiology, Polish Academy of Sciences, Warsawa, Poland) for discussions on sponge fossils and paleontology literature. Thanks to Karin Steffen (Uppsala University) for helping with the translation of paleontology articles in German. Caminus sp. (MNHN-IP-2015-1144) in Figure 4 originates from the deep-sea cruise BIOMAGLO conducted jointly by French National Museum of Natural History (MNHN) as part of the Tropical Deep-Sea Benthos program, the French Research Institute for Exploitation of the Sea (IFREMER), the French Southern and Antarctic Lands (TAAF), the Departmental Council of Mayotte and the French Development Agency (AFD), with the financial support of the European Union. I am grateful to the crew of R/V Antèa, especially C. Debitus in charge of collecting and documenting sponge specimens, as well as the cruise leaders of BIOMAGLO: L. Corbari, K. Olu-Le Roy, and S. Samadi. Geodia vaubani (MNHN-IP-2015-1667) in Figure 2 originates from the deep-sea cruise KANACONO expedition in New Caledonia (convention MNHN-Province Sud, APA_N_2016_012; PI: N. Puillandre and S. Samadi). KANACONO and KANADEEP2 expeditions operated under the regulations then in force in the country in question and satisfies the conditions set by the Nagoya Protocol for access to genetic resources. NIWA material was provided by the NIWA Invertebrate Collection, Wellington, New Zealand collected on the research programme: "Seamounts: their importance to fisheries and marine ecosystems," undertaken by NIWA and funded by the former New Zealand Foundation for Research, Science and Technology with additional funding from the former NZ Ministry of Fisheries and NOAA Satellite Operations Facility. Research was co-funded under Coasts and Oceans Research Programme 2 Marine Biological Resources: Discovery and definition of the marine biota of New Zealand (2019/2020 SCI). I am grateful to the Porifera Tree of Life (PorToL) project (Dr. Bob Thacker) and Dr. David Newman for providing permission to access the U.S. National Cancer Institute's (NCI) collection of sponges, housed at the U.S. National Museum of Natural History, Smithsonian Institution. These specimens were originally collected under contract to NCI by Dr. Pat Colin and Lori Bell Colin of the Coral Reef Research Foundation (CRRF), Koror, Palau; I thank CRRF for providing access to metadata for these specimens. DATA AVAILABILITY STATEMENT The datasets presented in this study can be found in online repositories. The names of the repository/repositories and accession number(s) can be found in the article/Supplementary Material. AUTHOR CONTRIBUTIONS PC conceived and designed the study, performed the observations, and the data analyses and literature surveys. PC wrote the manuscript. FUNDING PC received support by the European Union's Horizon 2020 Research and Innovation Program under Grant Agreement No. 679849 (the SponGES project). This document reflects only the authors' view and the Executive Agency for Small and Medium-sized Enterprises (EASME) is not responsible for any use that may be made of the information it contains. Visits to the NHM and the HBOI collections were funded by "Inez Johanssons" travel grants to PC (Uppsala University, HT2012, and HT2014). SUPPLEMENTARY METERIAL The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmars.2020.613610/full#supplementary-material Supplementary Figure 1 | Astrophorina 28S (C1–D2) maximum likelihood (ML) tree reconstructed with RAxML. ML bootstrap supports (1,000 bootstrap replicates) > 70 are indicated. Genbank accession numbers are given after each taxon. In bold are new sequences produced in this study. Geodiidae species have purple branches, Calthropellidae have brown branches. Red branches indicate Geodiidae species which secondarily lost sterrasters (species previously considered to belong to the Ancorinidae). Colored dots indicate sequenced species/specimens for which previous authors or this study have observed the surface of sterrasters with SEM (see Table 3 for references); round shapes represent sterrasters, flattened shapes represent aspidasters. Supplementary Table 1 | List of paleontological records of ball-shaped spicules (sterrasters, aspidasters, selenasters, rhaxes). Whenever the term "rhax" is used in publications it entails that it is a reniform-shaped spicule. "?" means missing data. Colors stand for periods: blue for Jurassic, green for Cretaceous and yellow/orange for Paleogene. In purple, comments on the identifications given in the papers. Supplementary Dataset 1 | Astrophorina COI alignment in FASTA format. Supplementary Dataset 2 | Astrophorina 28S (C1–D2) alignment in FASTA format.