Fig. 6 in New reticulosan sponges from the middle Cambrian of Sonora, Mexico

Fig. 6. Isolated spicules and associated fossils from the middle Cambrian El Mogallón Formation at Cerro El Mogallón, Sonora, Mexico. A, B, D. Spicules exhibiting 90° angles between four coplanar rays, and a vestigial fifth perpendicular ray, preserved as a central boss (arrows), indicating a geometry of three orthogonal axes. C. Assemblage of diverse disarticulated spicules. E. Stauractine with three smooth equal long rays and the forth longer. F, G. Fragments of possibly semi-articulated skeleton composed of stauractines and monaxons, with traces of a sub-regular, perhaps quadruled array. H. Fine monaxial spicules. I. Unidentified agnostoid trilobite and a typical cruciform stauractine. J. Possible anchoring spicule with two strongly recurved rays. K. Ptychagnostus atavus (Tullberg, 1880). L. Isolated, partial, presumed root tuft with two long parallel monaxons. M. USDG 001, triactine Kiwotinokia) and a long isolated monaxon; the arrow points to a possible ovoid sponge.