Schinderhannes Bartelsi

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Schinderhannes Bartelsi
Schinderhannes Bartelsi

Schinderhannes Bartelsi

Temporal occurrence
Lower Devonian
407.6 to 393.3 million years
Locations
Systematics
Primordial mouths (protostomia)
Dinocarida
Radiodonta
Anomalocarididae
Schinderhannes
Schinderhannes Bartelsi
Scientific name of the  genus
Schinderhannes
Kühl , Briggs & Rust , 2009
Scientific name of the  species
Schinderhannes Bartelsi
Kühl , Briggs & Rust , 2009

Schinderhannes bartelsi is a distant relative of the Anomalocarididae (Anomalocarida or more correctly: Anomalocaridida), which has so far only been passed down through a single find from the Lower Devonian (about 400 million years ago) of the Hunsrück slate . His discovery was unexpected, because previously similar fossils were only known from Cambrian fossil deposits that are about 100 million years older than the Hunsrück schist.

Anomalocarids are organisms like anomalocaris that are believed to be distantly related to the arthropods . However, they differ significantly from all known fossil and recent organisms - they had lateral praises for swimming and large compound eyes . Most noticeable are a pair of claw-like "large appendages" that are believed to have put the food in the mouth. These grippers are segmented and have a high degree of mobility.

discovery

The only known fossil specimen so far was found in the Eschenbach-Bocksberg quarry in Bundenbach and is named after the robber "Schinderhannes" who once made this area unsafe. The epithet bartelsi honors Christoph Bartels , an expert on fossils from the Hunsrück slate. The specimen is now in the Natural History Museum in Mainz.

morphology

Schinderhannes bartelsi is about 10 cm long and has a pair of “large appendages”, very similar to those of Hurdia , a radial Peytoia-like “pineapple ring” as a mouth and large stalked eyes. Its body is divided into 12 segments, large fin-like structures for swimming protrude from the 11th segment and from a region just behind the head.

ecology

Its intestines are preserved in a manner typically found in predators, and this way of life is aided by the predator-like nature of the spiky "large appendages" and the size of the eyes.

The organism could swim with certainty by moving with the "fins" on its head and steering with the wing-like lobes on the 11th segment. These lobes are believed to have originated from the lateral lobes of the Cambrian anomalocarids; Ancestors who used the rags on their sides for swimming and who did not yet have the specialization of Schinderhannes .

meaning

The organism could, to a certain extent, enable the classification of the early arthropods. He would then be counted among the real arthropods and would be closer to this group than anomalocaris . Schinderhannes could thus be understood as a kind of "uncle" of the arthropods, whereas Anomalocaris could be understood as a "great-aunt". This suggests that the anomalocarids form a paraphyletic group - meaning that the arthropods are descended from the anomalocarids. In particular, the anomalocarids would not have become extinct without offspring, as Stephen Jay Gould had assumed, which would have considerable consequences for the "growth form" of the family tree of living things. It also seems that the two-part appendages (antennae, mouthparts and legs, English: 'biramous limbs') of the arthropods were formed by the fusion of the lateral lobes with the gills of the anomalocarids. The existence of the fossil has other implications - it turns out that the group of early arthropods with short "large appendages" is not a natural grouping.

The discovery of this fossil is of great importance because of the strong extension of the geological lifespan of the anomalocarids: The group was previously only known from deposits in the lower to middle Cambrian, i.e. from a time 100 million years before Schinderhannes . This circumstance underlines the importance of the deposits of Hunsrück schist because of the fossils that are exceptionally well-preserved for the time they were formed and that may not be found anywhere else.

Individual evidence

  1. ↑ a b c d e f g Gabriele Kühl, Derek EG Briggs, Jes Rust: A Great-Appendage Arthropod with a Radial Mouth from the Lower Devonian Hunsrück Slate, Germany . In: Science . No. 323 , 2009, ISSN  0036-8075 , p. 771-773 , doi : 10.1126 / science.1166586 .
  2. ↑ a b Stephen Jay Gould : Chance Man. The miracle of life as a game of nature . WW Norton & Company / Hanser , Munich 1993, ISBN 3-446-15951-7 (English: Wonderful Life: The Burgess Shale and the Nature of History .).
  3. ↑ a b Alison C.Daley, Graham E. Budd, Jean-Bernard Caron, Gregory D. Edgecombe, Desmond Collins: The Burgess Shale Anomalocaridid Hurdia and its Significance for Early Euarthropod evolution . In: Science . No. 323 , 2009, pp. 1597–1600 , doi : 10.1126 / science.1169514 .
  4. ^ Nicholas J. Butterfield: Leanchoilia guts and the interpretation of three-dimensional structures in Burgess Shale-type fossils . In: Paleobiology . No. 28 , 2002, pp. 155 , doi : 10.1666 / 0094-8373 (2002) 028 <0155: LGATIO> 2.0.CO; 2 ( abstract [accessed on April 15, 2018]).
  5. ↑ Nicholas J. Butterfield: Secular distribution of Burgess-Shale-type preservation . In: Lethaia . 1st edition. No. 28 , 1995, doi : 10.1111 / j.1502-3931.1995.tb01587.x .

Remarks

  1. ↑ Wikipedia has an article on Peytoia

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