Reyes Montoya, Dulce RaquelCuen Romero, Francisco JavierNavas-Parejo, PilarGámez Meza, NohemíPalafox Reyes, Juan José2023-09-252023-09-2520231736-472810.3176/earth.2023.68https://hdl.handle.net/20.500.14352/87938Graptolites from the early Tremadocian Anisograptus matanensis Biozone are identified from east-central Sonora, northwestern Mexico, within a carbonate-shelf succession deposited on the southwestern continental shelf margin of Laurentia. This is the second occurrence of typical anisograptid graptolites in Mexico, after its original record in the Oaxaca area, which belongs to a Gondwana-related paleogeographical realm. The graptolites from Sonora represent the second global occurrence of any member of the Rhabdinopora flabelliformis group in the Ordovician equatorial shelf region.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/journal article1736-7557https://doi.org/10.3176/earth.2023.68open access563.719“6132”(721.5)OrdovicianTremadociangraptolite biostratigraphyLaurentiapaleoequatorial shelfMexicoPaleontología2416.02 Paleontología de Los Invertebrados