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Olenoides pugio (Walcott, 1908)
Etymology-from Olenus, in Greek mythology a man who, along with his wife Lethaea, was turned to stone. Olenus was used for a trilobite genus name in 1827; the suffix -oides(“resembling”) was added later. Synonyms-Olenoides was formerly known as Neolenus. Species of Kootenia are no longer considered different enough from those in Olenoides to warrant placement in a separate genus. Olenoides is an average size trilobite (up to 9 cm long), broadly oval in outline. Its cephalon is semi-circular. The glabella is parallel-sided, rounded at its front and almost reaches the anterior border. Narrow occular ridges curve backwards from the front of the glabella to the small, outwardly-bowed eyes. The librigenae narrow backward into straight, slender genal spines that reach as far as the third thorax segment. Thorax consists of seven segments that end in needle-like spines. pygidium) has six axial rings that decrease in size backwards and four or five pairs of rearward pointing marginal spines. Cephalon, thorax and pygidium are of approximately equal length.
Marjum Formation Miaolingian USAywang21
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Burlingia halgedahlae (Robison and Babcock, 2011)
Diagnosis—Exoskeleton generally oval in outline, width greatest along anterior thorax, medial posterior margin weakly indented. Cephalon subtriangular, lacking dorsal furrows. Anterior sections of facial suture straight, moderately divergent; posterior sections weakly curved, diverging laterally and slightly forward. Site of effaced occipital ring having small median node. Thorax containing as many as 15 segments, axis widest along midlength. Anterior border of thoracic pleurae raised to form low, narrow ridge. Pygidium narrowly rectangular. Etymology.—After Professor Susan L. Halgedahl, University of Utah, for contributions to knowledge of Cambrian fossils, stratigraphy and depositional environments in Utah. Holotype.—Exoskeleton, UU 10051.55 Discussion.—Burlingia halgedahlae most closely resembles B. hectori Walcott, 1908, from the Stephen Formation of British Columbia. and B. jagoi Whittington, 1994, from the Alum Shale of Sweden and Norway. It is similar to B. hectori in general outlines of the exoskeleton and thoracic axis but has a more triangular cephalon, one more thoracic segment, and a shallower medial indentation of the rear skeletal margin. It is similar to B. jagoi in having a subtriangular cephalon but differs in outline of the raised axial lobe, in having one more thoracic segment, and a deeper and wider indentation of the rear skeletal margin. Burlingia halgedahlae appears to differ from all other species of Burlingia by its greater effacement of dorsal furrows, but that feature may have a taphonomic rather than genetic origin. Occurrence.—Burlingia halgedahlae is rare in the middle part of the Marjum Formation, mid-Bolaspidella Zone, at localities 347 and 716 in the House Range.
Marjum Formation Miaolingian USAywang21