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Preservation of soft tissues in an Ordovician linguloid brachiopod from China

100%

Balinski A., Sun Y.

Acta Palaeontologica Polonica

2013

tom 58

nr 1

The findings of preserved soft body parts including pedicle in the linguloid brachiopods are extremely rare in the fossil record of which the early Cambrian Chengjiang (southern China) and Burgess Shale (British Columbia) faunas are the most important. However, these characteristic Cambrian soft−bodied faunas largely disappeared from the fossil re− cord well before the end of the Cambrian. Here we describe the first record of the pedicle in a linguloid brachiopod from the post−Cambrian strata, preserved with remarkable fidel− ity. Contrary to the Chengjiang and Burgess Shale−type fau− nas which are commonly preserved as essentially two−di− mensional aluminosilicate or degraded organic carbon films or pyritized compressed fossils, the specimens now recov− ered from the Ordovician of China show a three−dimen− sional, pyritized pedicle with preserved external morphol− ogy, in detail. The presence of streamlined shell shape and burrowing shell sculpture in our specimens supports an as− sumption for infaunal mode of life of the genus. Since all linguloid brachiopods of the early Cambrian are inter− preted as epifaunal or semi−infaunal, it seems that the here described Ordovician linguloid is the oldest representative of fully infaunal brachiopods. Apparently, the long vermi− form and flexible linguloid pedicle has appeared as a func− tionally optimized construction.

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

2004

tom 49

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.

Ograniczanie wyników

2 Acta Palaeontologica Polonica

1 Balinski A.

1 Han J.

1 Liu J.

1 Shu D.

1 Sun Y.

1 Zhang X.

1 Zhang Z.

1 2013

1 2004

Wyniki wyszukiwania

Preservation of soft tissues in an Ordovician linguloid brachiopod from China

Soft-tissue preservation in the Lower Cambrian linguloid brachiopod from South China