According toUbaghs (1978), syzygies are brachial articulations in which radiating ridges and furrows on the two joint faces oppose each other rather than interlock as in symplexies. Cryptosyzygies differ from syzygies by having very short ridges that may be replaced by rows of tubercles or granules, with a tendency toward irregular arrangement and disappearance. Among Triassic crinoids, only representatives of the orders Isocrinida Sieverts-Doreck, 1952 and Comatulida Clark, 1908 had cryptosyzygial or syzygial brachial articulation, respectively. According to Rasmussen (1978), among Isocrinidae the articulations of primibrachial 1 and 2 and secundibrachial 1 and 2 were cryptosyzygial or...

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