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Rosarichnoides sudeticus igen. et isp. nov. and associated fossils from the Coniacian of the North Sudetic Synclinorium (SW Poland)

Chrząstek A., Muszer J., Solecki A., Sroka A. M.

Geological Quarterly

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2018

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Vol. 62, No. 1

181--196

EN

A new ichnogenus and ichnospecies Rosarichnoides sudeticus is proposed for a large, exceptionally well-preserved crustacean burrow, which has been found in the Upper Cretaceous (Coniacian) Quadersandstein of the North Sudetic Synclinorium (Czaple quarry). Some of its specimens have been assigned to Thalassinoides saxonicus (Geinitz, 1842). It is unbranched, a characteristic rosary-shaped trace fossil, which consists of alternating chambers (swellings) and constrictions. The burrow is without any wall and usually lack ornamentation and has a passive fill. It should be included in ophiomorphid group sensu Bromley (1996). This unique finding resembles modern crustacean burrows produced by shrimps or crabs. Additionally, Thalassinoides paradoxicus (Woodward, 1830), the starfish Astropecten scupini Andert, 1934, the inoceramids Inoceramus kleini Müller, 1888 and Inoceramus sp. were found in the same sandstones. The trace fossils are indicative of the archetypal Skolithos ichnofacies that is typical of foreshore to middle shoreface settings.

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Patterns of occurrence and distribution of crustacean ichnofossils in the Lower Jurassic-Upper Cretaceous of Atlantic occidental margin basins, Portugal

Carvalho C., Baucon A., Rodrigues N., Santos V., Viegas P.

Acta Geologica Polonica

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2010

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Vol. 60, no. 1

19-28

EN

Crustacean ichnofossils are most abundant in the stratigraphic record of Portugal. In this paper is presented a study on crustacean ichnoassemblages from the Sinemurian to middle Cenomanian, during the opening and subsequent filling of Atlantic occidental margin basins (Lusitanian Basin and western part of Algarve Basin). Thalassinoides dominates the lagoonal and inner shelf facies from the late Sinemurian at least to the Turonian, generally defining all of the carbonate sequence with its dense, "nodular" ichnofabric since the Late Jurassic. Asequence is described in the lower Barremian of Cabo Espichel in which burrow mazes of Thalassinoides suevicus occur, containing hundreds of Mecochirus rapax as an obrution lagerstatte. The Cretaceous of the Lusitanian Basin is rich in marly limestones mottled with Thalassinoides but almost devoid of Rhizocorallium. Fairly common in dark marls and biomicrites from the Jurassic, Rhizocorallium irregulare locally occurs in dense monospecific fabrics. Slipper-shaped and oblique forms (Rhizocorallium jenense) as well as spiral and lobate forms are rhizocoralliid foraging modifications usually developed in deeper tiers than Thalassinoides and sometimes evidencing bioimprints in Glossifungites preservation. Siliciclastic facies related to rifting subsidence along major fault scarps and fan deltas/braided river depositional systems show pervasive bioturbation with Psilonichnus tubiformis.Another crab-style behaviour ascribed to Macanopsis plataniformis is described for the first time in Portugal, associated with a coarse-grained sandstone episode in a tidal flat setting from the Kimmeridgian, where monospecific brachyuran burrows were developed in a firmground.

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Crustacean Burrows from Upper Maastrichtian Deposits of South-Central Cuba

Pszczółkowski A.

Bulletin of the Polish Academy of Sciences. Earth Sciences

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2002

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Vol. 50, nr 2

147-163

EN

In south-central Cuba, the shallow-water limestones of the Late Maastrichtian Cantabria Formation underlie the Late Maastrichtian to Early Eocene Vaqueria Formation. The crustacean burrows (Thalassinoides isp.) occur in Late Maastrichtian marl of the lowermost part of the latter formation. Horizontal tunnels are the most common components of the reported low density burrow system produced in this shelfal deposit. Occurrence of Gansserina gansseri (Bolli), 1951, constrains the age of the burrow-filling biomicrite between 68 (probably 67) and 65.45 Ma. The submergence of the Cantabria shallow-water limestones and sedimentation of the burrow-filling biomicrite coincide with the high sea-level during Late Maastrichtian. The Late Maastrichtian deposits were partly truncated by pre-Palaeocene (K-T boundary?) erosion. However, in comparison with the successions of western Cuba, the Cienfuegos sedimentary basin occupied a more remote position in respect to the Chicxulub impact crater in Yucatan, thought to be the K-T event source.