Systematics and spicule evolution in dictyonal sponges (Hexactinellida: Sceptrulophora) with description of two new species Author Dohrmann, Martin Author Göcke, Christian Author Janussen, Dorte Author Reitner, Joachim Author Lüter, Carsten Author Wörheide, Gert text Zoological Journal of the Linnean Society 2011 2011-11-25 163 4 1003 1025 http://dx.doi.org/10.1111/j.1096-3642.2011.00753.x journal article 10.1111/j.1096-3642.2011.00753.x 0024-4082 5442435 EURETIDAE ZITTEL, 1877 Revised diagnosis (emended from Reiswig & Wheeler, 2002 , for inclusion of Sarostegia ; addition highlighted in bold): Body form either of branching and/or anastomosing tubes, or cup-funnel formed of a ring of tubes, or of a single tube, or of a single-wall funnel with or without lateral oscula extended on marginal tubes, or blade form; dictyonal meshes mainly rectangular or triangular or irregular; meshes usually equal-sided but elongate prismatic mesh series with transverse lamellae developed in some species; dictyonal strands, if developed, orientated longitudinally; with or without dictyonal cortices composed of primary or secondary dictyonalia; dermalia and atrialia are commonly pentactins or pinular hexactins with rays of approximately equal length, or both forms lacking; scopules, which might also be represented by sarules , and uncinates are usually present but are lacking in two genera; microscleres occur as oxyhexasters and/or discohexasters. Remarks: Euretidae , being the most species-rich family of Hexactinosida ( Reiswig & Wheeler, 2002 ; Leys et al ., 2007 ), is morphologically highly diverse and taxonomically poorly defined (see above); in lack of potential autapomorphies, its validity remains to be tested with molecular data.