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2 Acta Geologica Polonica

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Dobrogeria aegyssensis, a new early Spathian (Early Triassic) coelacanth from North Dobrogea (Romania)

Cavin L., Grădinaru E.

Acta Geologica Polonica

2014

Vol. 64, no. 2

161--187

The Early Triassic witnessed the highest taxic diversity of coelacanths (or Actinistia), a clade with a single living genus today. This peak of diversity is accentuated here with the description of a new coelacanth discovered in the lower Spathian (Upper Olenekian, Lower Triassic) cropping out in the Tulcea Veche (Old Tulcea) promontory, in the city of Tulcea, in North Dobrogea, Romania. The bone remains were preserved in a block of limestone, which was chemically dissolved. The resulting 3D and matrix-free ossifications correspond mostly to elements of the skull and branchial apparatus. Posterior parietals, postparietal with associated prootic and basisphenoid allow a precise description of the neurocranium. Ossifications of the lower jaw, together with branchial and pectoral elements, complete the description of this coelacanth and support the coining of a new generic and specific name, Dobrogeria aegyssensis. A phylogenetic analysis of actinistians with the new species recovers clades which were found in most recent analyses, i.e. the Sasseniidae, the Laugiidae, the Coelacanthiformes, the Latimerioidei, the Mawsoniidae and the Latimeriidae, and identifies the new taxon as a non-latimerioid coelacanthiform.

Coelacanths (Actinistia, Sarcopterygii) from the Famennian (Upper Devonian) of the Holy Cross Mountains, Poland

Szrek P.

Acta Geologica Polonica

2007

Vol. 57, no. 4

403-413

Coelacanth fishes from the Upper Devonian of the Holy Cross Mountains, Poland, are described. The material consists of isolated incomplete lower jaws, gular plates, an entopterygoid and urohyal. The isolated lower jaws belong to Diplocercides kayseri (VON KOENEN, 1895). The other coelacanth remains are referred to Diplocercides sp. indet. All specimens are Famennian in age (Early Palmatolepis rhomboidea conodont Zone), representing a time when almost all of the Holy Cross Mountains carbonate platform was drowned. Because of the shallow-water living conditions preferred by the group it is assumed that these coelacanths were restricted to isolated, small submarine swells, which still existed in that region in the latest Devonian, and that their carcasses were then subjected to post-mortem transport into the deeper areas.