Trilobites from the Crepicephalus Zone (upper Guzhangian Stage, Miaolingian Series, Cambrian) from northern Sonora, Mexico, and its correlation to Arizona and Texas, USA

• Published in: Journal of South American earth sciences 2021-06, Vol.108, p.103185, Article 103185
• Main Authors: Sundberg, Frederick A., Cuen-Romero, Francisco Javier
• Format: Article
• Language: English
• Subjects: Cambrian; Mexico; Sonora; Trilobite
• ISSN: 0895-9811; 1873-0647
• DOI: 10.1016/j.jsames.2021.103185

In the Cananea region, northeastern Sonora, there is a sedimentary sequence of the lower Paleozoic outcrops that includes the Cambrian Bolsa Quartzite and Abrigo Formation. This work describes and illustrates the upper middle Cambrian ptychopariid trilobite fauna from the Abrigo Formation for the first time for Mexico. Trilobites from the inner shelf deposits of the El Tule and Mesteña hills include Crepicephalus sp., Tricrepicephalus texanus, Llanoaspis modesta?, Coosella perplexa, Coosia ariston, and Coosia sp., which represent the Crepicephalus Zone (upper Guzhangian Stage, Miaolingian Series). The distribution of these species denotes a strong affinity with North American fauna, specifically with Arizona and Texas. •The first taxonomic work on upper Cambrian trilobites of northwestern Mexico is carried out.•Trilobite fauna consists of Crepicephalus sp., Coosia ariston, Coosella perplexa, Coosia sp., Tricrepicephalus texanus, and Llanoaspis modesta?•Biostratigraphic position represents the Crepicephalus Zone (upper Guzhangian Stage, Miaolingian Series).•The paleogeographic relationship of the Cambrian rocks of Sonora with the North American craton is confirmed.