Pennsylvanian trilobites from the Sangre de Cristo and Jemez Mountains, north-central New Mexico
— B. S. Kues

Trilobites are rare in marine Pennsylvanian strata of New Mexico. More than 100 specimens from Morrowan to Virgilian strata in the Sangre de Cristo and Jemez Mountains, belonging to five species, are described here. These are: aff. Paladin sp. (Morrowan), Sevillia trinucleata (Herrick) (upper Atokan-lower Desmoinesian), Sevillia sevillensis Weller (lower Desmoinesian), Ditomopyge scitula (Meek and Worthen) (Desmoinesian-middle Virgilian), and Ameura missouriensis (Shumard) (Atokan-middle Virgilian). These trilobites represent a depauperate but geographically widely distributed North American Pennsylvanian trilobite fauna. The taxa aff. Paladin sp., Ditomopyge scitula, and Ameura missouriensis appear to have preferred shallow, carbonate-shelf environments in which they occur with stenohaline groups such as brachiopods, bryozoans, and crinoids. Less commonly, the latter two species also occur in limestone assemblages dominated by bivalves and gastropods. The two species of Sevillia, on the other hand, are most common in dark-gray shales of the Flechado Formation, representing prodelta to interdistributary bay environments, where they occur with large numbers of gastropods and bivalves.