Esmeraldacaris richardsonae
| Esmeraldacaris richardsonae | ||||||||
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| Temporal occurrence | ||||||||
| Lower Ordovician | ||||||||
| 485.4 to 470 million years | ||||||||
| Locations | ||||||||
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| Systematics | ||||||||
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| Scientific name of the genus | ||||||||
| Esmeraldacaris | ||||||||
| Wagoner , 2003 | ||||||||
| Scientific name of the species | ||||||||
| Esmeraldacaris richardsonae | ||||||||
| Wagoner , 2003 | ||||||||
Esmeraldacaris richardsonae is an extinct species with an uncertain position within the arthropod (Arthropoda).
features
Esmeraldacaris richardsonae was a medium-sized, egg-shaped arthropod about 3 times as long as it was wide (maximum length 33.0 mm, maximum width 9.5 mm). The head shield was roughly triangular with a short blunt front edge and a pair of short spines. The thorax consisted of a maximum of 7 tergites , all of which ran perpendicular to the longitudinal axis without deflection and ended without lateral spines. The last tergite in front of the blunt, trapezoidal tail shield, about the size of a head shield, was about half as long as the others.
etymology
The genus name is made up of Esmeralda , the name of the county in which the species was found, and the Latin word caris for shrimp. The specific epithet was chosen in honor of Sara Richardson, who found a specimen in the summer of 2000.
Location
The species was found between the Emigrant and Palmetto Formations in the northern part of the Silver Peak Range in Esmeralda County , Nevada . The holotype (USNM 520698) as well as another complete (USNM 520699) and two partially preserved copies (USNM 520700 and 520701) are now in the National Museum of Natural History in Washington, DC
Systematics
The systematic position within the arthropods could not yet be determined. Esmeraldacaris resembles some isopods (Isopoda) with large telson such as Idotea , Sphaeroma and related forms. There is no resemblance to most of the trilobites , but some can be found with Kleptothule , from the suborder Olenellina .
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literature
- Ben Wagoner: Non-trilobite arthropods from the Silver Peak Range, Nevada . Journal of Paleontology 77 (4), 2003: 706-720. HTML
Individual evidence
- ^ RR Hessler: Peracarida . In: RC Moore (Ed.): Treatise on Invertebrate Paleontology, Part R, Arthropoda 4 . Geological Society of America and University of Kansas Press, Lawrence, 1969: Figs. 193-194.