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A Late Devonian to (?)Early Mississippian section at Hushoot Shiveetiin gol in the Baruunhuurai Terrane of the Central Asian Orogenic Belt (CAOB) exposes large parts of cyclic Famennian shallow-water siliciclastic shelf deposits composed of siltstones, sandstones, shales, volcaniclastics, and intercalated autochthonous carbonates. The youngest part of the section, possibly Early Mississippian, is represented by arkosic sandstones with large plant remains. The facies reflects a range from shallow-intertidal to outer ramp settings. In terms of conodont stratigraphy, the Hushoot Shiveetiin gol section ranges from the Palmatolepis minuta minuta Biozone to at least the Palmatolepis rugosa trachytera Biozone. Hiatuses of several conodont biozones occur due to the facies setting (erosion and reworked sediments which are recognized by reworked conodonts) rather than thrusting or folding. The environmental setting was characterized by coeval subaerial volcanism resulting in numerous pyroclastic deposits. The depositional environments and intense volcanic activity at the Hushoot Shiveetiin gol section limited the stratigraphic distribution, abundance, and diversity of many elements of the fauna such as brachiopods. Ostracods were very abundant and diverse through many parts of the section. Although limited in stratigraphic distribution, the crinoid fauna is the most diverse Palaeozoic fauna collected from Mongolia to date and supports the hypothesis that the CAOB was a biodiversity hotspot in the aftermath of the Frasnian–Famennian extinction event.

Crinoids have the ability to regenerate their crowns when arms are autotomized or bitten off by predators. The evidence of predation is visible in many populations of crinoids, including the deep water stalked crinoid Democrinus off the coast of Roatán, Honduras. Throughout the videos taken in a submersible, many individuals displayed arms that are significantly shorter relative to their stalk lengths than the full‐grown adults in the area, indicating arm regeneration. Some individuals were missing crowns completely, strongly suggesting predation by fishes. Our calculated predation rate of 17.25% including individuals missing a crown or regenerating their arms in situ is significantly greater than that rates determined in previous studies of predation on Democrinus. Copyright © 2016 John Wiley & Sons, Ltd.

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