Kiisortoqia
- Greenland
Kiisortoqia soperi is an extinct Arthropodenart from the early Cambrian Sirius - Passet - Faunengemeinschaft. The large antennas are very similar to those of the Anomalocaridida.
Features
The body of Kiisortoqia soperi consisted of a simple head shield, 16 trunk segments ( tergites ) and a tail shield. The type reached a length 234-534 mm and was approximately elliptical, about twice as long as wide in its external appearance, with the widest point in the front third of the body during 3rd to 5th tergite.
The head plate was simple, convex in shape, wider than long, and made about 20 % of the total body length of. The tergites were short, about five times as wide as long, and the rear edge of each Tergits superimposed the following by about one-fifth of its length. The tergites 1-5 all had about the same width, the following tergites were always narrower backwards coming. In the middle of an axis was clearly to identify which accounted for about half the width of a Tergits and gave him a three-lobed shape. At the lateral ends of each Tergits backwards towards longer and longer spines were present. The small tail sign was semicircular, about half as long as wide and the front half to two-thirds of the tail shield also had a three-lobed shape.
At the head shield ventral sat a pair of large limbs, the so-called antennule, which is about half to two thirds were so long as the body. They consisted of a handle and 15 cylindrical members, wherein the pedicle was twice as long as the following elements. The limbs showed a flat outside and two widely spaced spines towards the center.
The other limbs, three pairs on the head shield and 16 more on each body segment, consisted of two branches (made up as a gap leg in crustaceans ) and took until the 5th tergite in their size and were then smaller again. The Basipodit was long, trapezoidal, and had two rows with different number of thorns. The endopodite consisted of nine cylindrical Poditen. The eighth Podit had two lateral spines, which flanked the ninth long Podit. The exopodite was a paddle -like lobes, which was fringed with bristles. The length Con t just over two -thirds of the length of the Endopodits.
Way of life
An accurate way of life can not be determined because of the lack of direct evidence, but it can draw conclusions on the basis of morphology are drawn.
It is believed that Kiisortoqia soperi was a predatory wild swimmers. The large paddle-like Exopodite were probably suitable for swimming. With the robust antennule K. soperi could probably capture its prey and attack with the spiky Basipoditen its prey and lead to the mouth.
Etymology
The name of the genus comes from the Greenlandic word for kiisortoq predators or hunters from. The specific epithet was chosen in honor of Norman John ( "Jack" ) Soper, who gathered together with AK Higgins, the discoverer of the Sirius Passet - Faunengemeinschaft, the first fossils there.
Locations
More than 170 specimens of the species were during various expeditions 1985-2006 found in the Cambrian Konservatlagerstätte Sirius Passet on Pearyland in North Greenland. The specimens are preserved mostly more or less completely, fragmented fossils were not discovered.
Systematic position
Kiisortoqia soperi fulfills three basic characteristics of arthropods in the strict sense ( Euarthropoda ): A head shield with antenna or antennule and three pairs of other extremities, postantennulare zweiästige limbs and a skirted with bristles exopodite. A precise position within the arthropods can not be determined, however, due to the possible lack of eyes and the shape of the tail shield. A possible synapomorphy of antennule with the jaw -mouth media ( Chelicerata ) is purely speculative.