This is Mazon Monday post #141. What's your favorite Mazon Creek fossil? Tell us at email:[email protected]. Thanks!
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Kottixerxes gloriosus is a very rare animal in the Essex biota of Mazon Creek. Out of 229,979 from Pit 11, only two were found! That leaves it tied with centipedes are the rarest animals. Even amphibians were more common, with three total in the sampling of 229,979. Those statistics come from the "Richardson's Guide to the Fossil Fauna of Mazon Creek".
K. gloriosus was described in the paper "A strange arthropod from the Mazon Creek of Illinois and the Trans Permo-Triassic Merostomoidea (Trilobitoidea)" by Frederick Schram in 1971. Dr. Schram described many of the shrimp found in the Mazon Creek fossil biota. The holotype was donated to the Field Museum by A. W. Kott of Summitt, Illinois. Scham's paper lists a few more specimens. Some of which, now reside in the Field Museum. You will recognize some of those names as some made other significant contributions to the study of Mazon Creek fossils.
Mr. A. W. Kott of Summitt, Illinois
Mr. Jerry Herdina, Berwyn, Illinois
Mr. and Mrs. Levi Sherman, Des Plaines, Illinois
Mr. Francis Tully, Lockport, Illinois
Mr. and Mrs. Ted Piecko, Chicago, Illinois
Mr. and Mrs. Fran Wolff of Park Forest, Illinois
Fig. 6. Holotype of Kottixerxes gloriosus, PE11010.
K. gloriosus appears on page 46 of Jack Wittry's "The Fossil Fauna of Mazon Creek".
Euthycarcinoids are a group of arthropods considered to be marine cousins of insects and myriapods. A primitive head bears lobed eyes and antennae. Little is known of their mouth parts. The thorax of these articulated animals is covered by wide tergites (back plates). The number of tergites serves as a means to separate the three genera found in the Essex Fauna. This book features the two more common genera.
Kottixerxes gloriosus, the most often found, has six smooth tergites; Smithixerxes juliarum has five crested tergites and is known from dorsal views only. In both, a long, narrow, segmented abdomen is found behind the thorax, ending in a elongated, tapered telson (tail), which gives each of these unusual animals a strange appearance. The third genus, Pieckoxerxes [= Scottyxerxes] pieckoae, is very rare.
Specimens
From the "Richardson's Guide to the Fossil Fauna of Mazon Creek".
From Wittry's "The Fossil Fauna of Mazon Creek".
