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New taxa of spiriferids are described, highlighting their unique valve anatomy and fossil microorganisms.
New taxa of spiriferids are described from the Late Emsian of North-East Eurasia (Ulahan-Sis Ridge). These are the genus Trushelevia gen. nov. with the type species T. yania sp. nov. from the subfamily Delthyridinae Phillips, 1841 and the genus Kirichkovia gen. nov. with the type species K. sibirica sp. nov. from the subfamily Howellellinae Johnson et Hou, 1994. The valves of this species consist of three layers: primary, secondary and prismatic. The secondary layer is permeated with pores, with fossil microorganisms found within them.
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Baranov et al. (2025) studied this question.
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