Field photographs of platform-top bed in the Seguilí Formation (upper part of SF-2) in the Sierra de Seguilí (see Fig. 13 for section details): a: panoramic view of vertical section of bed, with crest of Mathesia cluster outlined by dotted line; b: detail of autochthonous Mathesia cluster (= white rectangle in (a)); c: close-up view of mutually attached right valves of Mathesia darderi (Astre, 1933) preserved in life position (arrow indicates eroded section of diagnostic fine canals at inner margin of outer shell layer; see Fenerci-Masse et al., 2011); d: detail of wackestone at top part of bed (under man’s hand at top right in (a)), with scattered large requieniids and burrows secondarily filled from above by orange-stained sediment. Scale bars: c: 10 mm; d: 100 mm.