Figure 7. (1) Holocystites scutellatus (SUI 48183). Theca squat, globular with numerous tumid plates with moderately impressed sutures. Distal end tapers considerably into holdfast. (2) Trematocystis magniporatus (SUI 48198). Theca squat, with large and flat plates, without impressed sutures. Theca narrows slightly into holdfast. (3) Paulicystis sparsus (SUI 48164). Theca squat, globular with numerous small, tumid plates with deeply impressed sutures. Theca widens distally into holdfast. (4) Pentacystis gibsoni (SUI 46316). Theca elongate to globular with relatively large, flat plates without impressed sutures. Theca narrows moderately into holdfast. (5) Osgoodicystis bissetti (SUI 48166) is highly morphologically similar to Pentacystis; theca elongate with relatively large, flat plates without impressed sutures. Theca narrows moderately into holdfast. Note that circular depressions on theca are attributed to parasitic embedment structures, Oichnus Bromley (Tremichnus sensu Brett, 1985b). (6) Holocystites sp. (YPM 34764). Theca is relatively large and narrows considerably distally. Plates are highly disorganized and of multiple generations. (7) H. cylindricus (YPM 19175). Theca is elongated and cylindrical without distal constriction. Plates are organized and of one generation. (8) Holocystites sp. (YPM 519465). Theca is squat and globular and narrows distally into holdfast. Plates are disorganized and of multiple generations. Scale bar = 1 cm.
facetal plate (Fig. 6.1, 6.2). Oral plate series slightly rotated clockwise with respect to ambulacra. Thecal plates tumid with sunken sutures (Fig. 7.1).
Remarks.—This diagnosis is based on preserved oral areas of multiple Holocystites species. Holocystites bears the stereo- typical peristomial plate arrangement of holocystitids. All five
