RT Journal Article
T1 Cephalopods of the San José Formation of Peru (Floian, Early Ordovician) and their paleogeographic significance
A1 Kröger, Björn
A1 Chacaltana, César
A1 Gutiérrez Marco, Juan Carlos
AB The existence of Ordovician Peruvian cephalopods has been known since at least the 1910s. However, they have not been effectively documented previously with only a few described taxa listed in open nomenclature. Here, we describe a cephalopod assemblage at the finest taxonomic level possible. The specimens were collected from the Floian section (Baltograptus minutus graptolite Zone) of the San José Formation from the Kimbiri area, northwest of Cuzco (= Cusco), and from a section along the Inambari River, southeastern Peru. The dark mudstone-siltstone of the San José Formation was deposited within the Central Andean Basin. The assemblage contains five species of small orthoceracones belonging to four families and three orders, consisting of one indeterminate dissidocerid, one bathmoceratid (Saloceras sp.), one rioceratid (Rioceras? sp.), and two baltoceratids belonging to Annbactroceras grecicostatum (Kobayashi, 1937), and Bactroceras cocafolium new species. The dominance of small orthoceracones is typical for early Paleozoic pelagic cephalopod assemblages. One species, A. grecicostatum, is known from elsewhere in the Central Andean Basin. The other taxa indicate a peri-Gondwana-Avalonia paleogeographical relationship of the cephalopod fauna, which is consistent with previously published data from brachiopods and trilobites.
PB Cambridge University Press
SN 0022-3360
YR 2024
FD 2024-09
LK https://hdl.handle.net/20.500.14352/119877
UL https://hdl.handle.net/20.500.14352/119877
LA eng
NO Kröger, B., Chacaltana, C. A., & Gutiérrez-Marco, J. C. (2024). Cephalopods of the san josé formation of peru (Floian, early ordovician) and their paleogeographic significance. Journal of Paleontology, 98(5), 795-807. https://doi.org/10.1017/jpa.2024.46
NO Ministerio de Ciencia, Innovación y Universidades
NO IUGS-UNESCO
DS Docta Complutense
RD 24 dic 2025