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Exceptional soft-tissue preservation in boring ctenostome bryozoans and associated “fungal” borings from the Early Devonian of Podolia, Ukraine

100%
Olempska E.
Acta Palaeontologica Polonica
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2012
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tom 57
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nr 4
Colonies of boring ctenostome bryozoans and microborings of “fungi” that occur in the Early Devonian (Lochkovian, ~416 Ma) of Podolia, western Ukraine, have soft−tissue preserved by phosphatization. These comprise exceptional three−dimensional body walls of feeding zooids with probable parietal muscles inserted on the cystid wall, and setigerous collars twisted within the vestibulum. The presence of collars in this Early Devonian ctenostomes proves the existence of this feature for more than 416 Ma of ctenostome evolution. Phosphatized remains of the zooid walls are interpreted as relicts of the originally chitinous cystid walls. This is the first record of soft−tissue fossilization in a boring bryozoan. The presence of cavities (specialized heterozooids), empty or filled with laminated calcium phosphate, is also documented in bryozoans for the first time. These cavities are interpreted as “store−rooms” in which the bryozoans accumulated nutrients. The new taxon, Podoliapora doroshevi gen. et sp. nov. is described. In additional, phosphatised fungi−like endoliths co−occur with bryozoans.
2
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Pyritized tube feet in a protasterid ophiuroid from the Upper Ordovician of Kentucky, U.S.A.

100%
Glass A.
Acta Palaeontologica Polonica
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2006
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tom 51
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nr 1
A single specimen of the protasterid ophiuroid Protasterina flexuosa from the Kope Formation (Cincinnatian, Upper Ordovician) of Kentucky exhibits three−dimensionally pyritized tube feet. This represents the first report of soft−tissue preservation in an echinoderm from the type−Cincinnatian series. The tube feet are solid and lack all internal structure. They consist of aggregated masses of small euhedral to subhedral pyrite crystals suggesting that pyritization, although decay−induced and mediated, did not necessarily replicate soft−tissues but might instead have formed inside the void−spaces left behind during the decay process. The discovery of pyritized soft−tissue as delicate as ophiuroid tube feet suggests that similar forms of soft−tissue preservation might be found in other taxa in the Kope Formation. Perhaps much more importantly, this unexpected occurrence demonstrates the incompleteness of our knowledge of permissible conditions for the preservation of soft−tissues and it thereby indicates promise for discovery of other such occurrences in diverse organisms in unexpected settings. Systematics of Paleozoic ophiuroids remains problematic in spite of many years of study by capable paleontologists. The incomplete but well−preserved specimens treated here include the types of Protasterina flexuosa and Protasterina fimbriata as well as previously undescribed specimens. Together they permit a revised diagnosis and detailed description of the genus Protasterina. Protasterina fimbriata is the type species of the genus but is a subjective junior synonym of Protaster flexuosus (= Protasterina flexuosa). The genus is clearly differentiated from the only other known protasterid ophiuroid from the Cincinnatian series, Taeniaster spinosus, and from all other protasterid genera.
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Soft-tissue preservation in the Lower Cambrian linguloid brachiopod from South China

100%
Zhang Z., Han J., Zhang X., Liu J., Shu D.
Acta Palaeontologica Polonica
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2004
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tom 49
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nr 2
The organization of the lophophore and the digestive system are recognized as two of the diagnostic characters in the definition of higher brachiopod taxa, and hence play a major role in their phylogenetic analysis, their structure, however, is very rarely fossilized. Here we describe and interpret specimens of the brachiopod Lingulellotreta malongensis, from the Lower Cambrian Chengjiang Lagerstätte (South China), one of the earliest known taxa of the Lingulellotretidae, in which lophophores and intact, U−shaped digestive tracts are extraordinarily well−preserved. The lophophore, with clearly preserved tentacles, corresponds to an early spirolophe developmental stage. The digestive tract consists of a mouth, esophagus, distended stomach, intestine and an anterior anus, and differs from that of the Chengjiang obolid Lingulella chengjiangensis by the presence of the dilated stomach and by the absence of a looped intestine as in Lingula. In addition, the relative sizes of the mantle and visceral cavities of Lingulellotreta malongensis also are described. These fossils demonstrate that by the Atdabanian brachiopods had already possessed advanced features, and suggest that a lophophore and a U−shaped intestine with an anterior anus are brachiopod plesiomorphies.
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