Cryptovenator

• Germany, Rhineland -Palatinate

• Cryptovenator hirschbergeri Fröbisch et al. 2011

Cryptovenator (Greek kryptos, "hidden", "secret " and Latin venator, " Hunter") refers to a genus of basal sphenacodontider " Pelycosaurier " ( Synapsida ) from the late Upper Carboniferous of Germany. The type and only species Cryptovenator hirschbergeri was first described in 2011 based on the anterior part of the mandible from the Saar -Nahe Basin ( Rhineland -Palatinate ), derived from a sandstone of the middle Remigiusberg lineup. This fossil represents the oldest remains of amniotes in Germany.

With an estimated total length of approximately one meter Cryptovenator is one of the smaller members of the Sphenacodontiden.

Locality

The type and only known specimen of Cryptovenator hirschbergeri originates from the western edge of the Remigiusberg - quarry near Haschbach in the southern Rhineland- Palatinate. The quarry is the type locality of 300 million years ( late Gzhelium ) dated Remigiusberg Formation, the basal formation of the Permian of the Saar -Nahe Basin. The Fund layer belongs to a mixed carbonate - siliciclastic succession of deposits of the so-called Theisbergstegen Lake ( Lower Theisbergstegen bank).

The Remigiusberg quarry has produced many well-preserved fossils of fish and amphibians and is also rich in fossil kick seals purely terrestrial land vertebrates, probably dating from Diadectiden, para reptiles, Diapsiden and synapsids. Body fossils of amniotes were not known from there to the discovery of Cryptovenator.

Description

Of the holotype Cryptovenator hirschbergeri is the front half of the lower jaw, which consists mainly of the dental and whose length is about 5 centimeters. It is equipped with 11 teeth, of which the front three are significantly larger than the remaining teeth - so-called caniniforme ( fang -like ) teeth ( see also → Heterodontie ). Of these three caniniformen teeth is again the second most. All teeth have a roughly teardrop-shaped outline. Striking is the large amount of the entire anterior portion of the dentary, including the symphysis. In addition, lower, rear portion of the dentary is distinctly curved upwards. All these are typical characteristics of Sphenacodontiden who find themselves in a similar manner in the genera Sphenacodon and Dimetrodon.

Haptodus

Palaeohatteria

Pantelosaurus

Ianthodon

Cutleria

Secodontosaurus

Cryptovenator

Sphenacodon

Ctenospondylus

Dimetrodon

Therapsida

System

The drop-shaped contour of the teeth, the caniniformen front teeth, the high pubic symphysis and the pronounced upward curvature of the rear part of the traditional jaw bone have undoubtedly Cryptovenator than Sphenacodontiden. The squat training of the jaw and the only moderately pronounced Heterodontie shall be regarded as autapomorphies of Cryptovenator. When teeth geologically younger representatives of the Sphenacodontiden how Sphenacodon, Ctenospondylus or Dimetrodon from the Early Permian, the Heterodontie is much more pronounced - and Others, the first tooth of the lower jaw is in these forms significantly reduced in size. Therefore Cryptovenator is a relatively original Sphenacodontide. But because he more features with the most derived genera Dimetrodon or Sphenacodon divides as with Secodontosaurus, Cryptovenator is not quite at the base of Sphenacodontidae.

Importance

The traditional permokarbone fauna of the Saar-Nahe Basin in general and the Remigiusberg formation in particular is dominated by aquatic vertebrates. On the other hand come in the fossil record of other Rotliegendbecken, as in the Thuringian Forest ( Bromacker ) or Upper Silesia ( Nowa Ruda ), basal synapsids ( " Pelycosaurier " ) relatively frequently.

Cryptovenator is the first find of amniotes in the Saar -Nahe Basin, and especially the first find of a representative sphenacodontider " Pelycosaurier " who were there represented until then only indirectly through the ichnotaxon Dimetropus. After Macromerion schwarzenbergii from Kounová in the Czech Republic is at Cryptovenator also the second- oldest find of a Sphenacodontiden in Europe.

The direct detection of Sphenacodontiden, the most derived forms of " Pelycosaurier ", in the late Carboniferous supports the assumption that the diversification of the early amniotes took place long before the transition from the Carboniferous to Permian. Due to the sparse Carboniferous fossil record of amniotes, however, it remains unclear whether this process relatively quickly took place within a few million years at the end of the Carboniferous or reaches far back into the early Carboniferous.