Sceptrulophora (from Ancient Greek, σκῆπτρον, skêptron - "sceptre" and -φόρος, -phóros - "bearing") is an order of hexactinellid sponges (glass sponges). They are characterized by sceptrules, a type of microsclere (microscopic spicule) with a single straight rod terminating at a bundle of spines or knobs. An anchor- or nail-shaped sceptrule is called a clavule. A fork-shaped sceptrule, ending at a few large tines, is called a scopule. A broom-shaped sceptrule, ending at many small bristles, is called a sarule.
Unlike members of the order Lyssacinosida, sceptrulophorans have dictyonal strands, meaning that their macroscleres (larger spicules) are fully fused together into a 3D framework. They can likewise be differentiated from the order Lychniscosida by the absence of octahedral frames (lychniscs) at the nodes of their macroscleres. Glass sponges with these two traits (dictyonal strands and a lack of lychniscs) have historically been placed in the order Hexactinosida (sometimes spelled Hexactinosa).Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volume 3: Classes Demospongea, Hexactinellida, Heteractinida & Calcarea, xxxi + 872 p., 506 fig., 1 table, 2004, available here. .Treatise on Invertebrate Paleontology Part E, Revised. Porifera, Volume 2: Introduction to the Porifera, xxvii + 349 p., 135 fig., 10 tables, 2003, available here. .
Many species in "Hexactinosida" also qualify as members of Sceptrulophora, though these two proposed orders are not identical. Sponges in the family Dactylocalycidae have dictyonal strands and lack lychniscs, but also lack sceptrules. Genetic testing has argued that dactylocalycids are more closely related to Lyssacinosida, rather than sceptrule-bearing sponges. This renders Hexactinosida polyphyletic while maintaining the monophyly of Sceptrulophora.MARTIN DOHRMANN, CHRISTIAN GÖCKE, DORTE JANUSSEN, JOACHIM REITNER, CARSTEN LÜTER, GERT WÖRHEIDE, Systematics and spicule evolution in dictyonal sponges (Hexactinellida: Sceptrulophora) with description of two new species, Zoological Journal of the Linnean Society, Volume 163, Issue 4, December 2011, Pages 1003–1025, https://doi.org/10.1111/j.1096-3642.2011.00753.x
Species of the order Sceptrulophora have existed since the Jurassic period, and still flourish today.
Families Aphrocallistidae Gray, 1867Gray, J.E. (1867). Notes on the Arrangement of Sponges, with the Descriptions of some New Genera. Proceedings of the Zoological Society of London. 1867(2): 492-558, pls XXVII-XXVIII. Auloplacidae Schrammen, 1912Schrammen, A. 1912. Die Kieselspongien der oberen Kreide von Nordwestdeutschland. II. Teil. Triaxonia (Hexactinellida). Palaeontographica 5 (supplement): 177-385, pls XXV-XLV. Craticulariidae Rauff, 1893Rauff, H. (1893-1894). Palaeospongiologie. Palaeontographica. 40: i-vi, 1-346, pls I-XVII. Cribrospongiidae Roemer, 1864Roemer, F.A. 1864. Die Spongitarien des norddeutschen Kreidegebirges. Palaeontographica 8: i-iv, 1-64, pls I-XIX. Euretidae Zittel, 1877Zittel, K.A. (1877). Studien über fossile Spongien. I: Hexactinellidae. Abhandlungen der Mathematisch-Physikalischen Classe der Königlich-Bayerischen Akademie der Wisseneschaften. München 13(1): 1-63. Farreidae Gray, 1872Gray, J.E. (1872). Notes on the Classification of the Sponges. Annals and Magazine of Natural History. (4) 9(54): 442-461 Fieldingiidae Tabachnick & Janussen, 2004Tabachnick, K.R.; Janussen, D. (2004). Description of a new species and subspecies of Fieldingia, erection of a new family Fieldingidae and a new order Fieldingida (Porifera; Hexactinellida; Hexasterophora). In: Pansini M, Pronzato R, Bavestrello G, Manconi R, Sarà M (eds) Sponge Science in the New Millennium. Bollettino dei Musei e degli Istituti Biologici dell'Universitá di Genova. 68: 623-637. Tretodictyidae Schulze, 1886Schulze, F.E. (1886). Über den Bau und das System der Hexactinelliden. Abhandlungen der Königlichen Akademie der Wissenschaften zu Berlin (Physikalisch-Mathematisch Classe). 1-97. Uncinateridae Reiswig, 2002Reiswig, H.M. (2002). Family Uncinateridae fam. nov. pp. 1372-1376. In Hooper, J. .A. & van Soest, R.W.M. (ed.) Systema Porifera. A guide to the classification of sponges. Vol. 2 (Kluwer Academic/ Plenum Publishers: New York, Boston, Dordrecht, London, Moscow). incertae sedis Coronete Ijima, 1927 Cyrtaulon Schulze, 1886 Lefroyella Thomson, 1877 Verrucoeloidea Reid, 1969
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