Papers by wolfgang stinnesbeck
Palaeogeography, Palaeoclimatology, Palaeoecology, Feb 1, 2022
Supplement to "Subaqueous speleothems (Hells Bells) formed by the interplay of pelagic redoxcline... more Supplement to "Subaqueous speleothems (Hells Bells) formed by the interplay of pelagic redoxcline biogeochemistry and specific hydraulic conditions in the El Zapote sinkhole, Yucatán Peninsula, Mexico". Fig. S1: pH-logs of EXO-1 probe deployed at a dive down to 45 m water depth. The probe was attached to the gas bottle of a technical diver and pH was logged every second. The pH-electrode reacted on elevated sulfide concentrations below 36 m water depth resulting in higher pH readings. This is evident in the pH readings on the way up that are elevated compared the readings on the way down. However, the probe seems to regenerate itself in some time after the exposure to sulfide.
Late Campanian through Maastrichtian sea-level changes are examined based on lithology, macrofoss... more Late Campanian through Maastrichtian sea-level changes are examined based on lithology, macrofossils and benthic foraminifera at the Elles and El Kef sections in Tunisia. Six major sea-level regressions are identified during the late Campanian (74.4-74.2 Ma, 74.0-72.5 Ma), the Campanian-Maastrichtian transition (72.2-70.3 Ma), early Maastrichtian (69.6-69.3 Ma, 68.9-68.3 Ma), and late Maastrichtian (~65.5 Ma). Correlation of the Maastrichtian sea-level regressions with the oxygen isotope record of DSDP Site 525 in the middle latitude South Atlantic reveals that they coincide with episodes of high latitude cooling and appear to be of eustatic origin.
Palaeogeography, Palaeoclimatology, Palaeoecology, Sep 1, 2016
Here we present evidence for a semi-sessile early juvenile stage of ammonites. Our hypothesis is ... more Here we present evidence for a semi-sessile early juvenile stage of ammonites. Our hypothesis is based on fossil evidence in early diagenetic limestone concretions discovered in platy limestone deposits of Cenomanian age in the northern state of Coahuila, Mexico. In these locations densely packed post-embryonic shell assemblages were attached to fossilized algal or bacterial mats and preserved in sediments deposited under permanently anoxic bottom conditions. Tiny ammonites, as well as gastropods and byssate pectinid bivalves are abundant and restricted to these mats. They do not occur elsewhere in the sediment. The ammonite hatchlings were apparently unable to escape from mats sinking to the hostile sea floor and must thus have been semi-sessile, similar to the associated gastropods and bivalves.
Journal of Vertebrate Paleontology, 2014
This paper describes a new species of elasmosaurid plesiosaur, Aristonectes quiriquinensis, sp. n... more This paper describes a new species of elasmosaurid plesiosaur, Aristonectes quiriquinensis, sp. nov., based on a partial skeleton recovered from upper Maastrichtian beds of the Quiriquina Formation of central Chile. The material described here consists of two skeletons, one collected near the village of Cocholgue, and a second juvenile specimen from Quiriquina Island. Prior to these finds, Aristonectes was viewed as a monospecific genus, including only the enigmatic Aristonectes parvidens, the holotype of which consists of an incomplete skull and incomplete postcranium. Other material referred to the genus includes an incomplete juvenile skull and other postcranial material from the upper Maastrichtian of Antarctica, as well as a partial skull from the Quiriquina Formation of central Chile. The relationships of Aristonectes have been controversial, with competing theories assigning the genus to Cryptoclididae, Elasmosauridae, and Aristonectidae; however, there is a developing consensus that Aristonectes is a derived elasmosaurid, and this paper gives strong evidence for this view. Comparison of the specimen here studied with the holotype of A. parvidens demonstrates that A. quiriquinensis is a distinct species. The completeness of the adult skeleton allows the first confident size estimates for adult Aristonectes. It is a large plesiosaurian with a relatively large skull with numerous homodont teeth, a moderately long and laterally compressed neck, and relatively narrow trunk, with slender and elongate forelimbs. The two specimens are restricted to the upper Maastrichtian of central Chile, posing questions concerning the austral circumpolar distribution of different elasmosaurids towards the end of the Cretaceous.
Cretaceous Research, Nov 1, 2021
Abstract The Turonian plattenkalk of Vallecillo (Mexico) yielded two large-sized gladiuses of oct... more Abstract The Turonian plattenkalk of Vallecillo (Mexico) yielded two large-sized gladiuses of octobrachian coleoids. The specimens determined as Boreopeltis ifrimae sp. nov. are both classified as members of the suborder Prototeuthina and represent the first coleoids from the Turonian of Mexico. Belemnoid coleoids are still unknown from Upper Cretaceous localities in Mexico. Boreopeltis ifrimae sp. nov. is the youngest representative of its genus. The occurrence of Boreopeltis in the northwestern Gulf of Mexico suggests a worldwide distribution in cold to warm temperate waters. The gladius (mantle) length of both specimens is remarkable and measures 470 mm, respectively. A general trend towards large and very large-sized coleoids is identified during the Late Cretaceous and began in the Turonian, as indicated by taxa from the southern Western Interior and the northern Gulf of Mexico. This gradual increase in octobrachian body sizes may reflect a commencing escalation in the arms race between coleoids, fishes, and marine reptilians.
EGS - AGU - EUG Joint Assembly, Apr 1, 2003
GSA Annual Meeting in Indianapolis, Indiana, USA - 2018, 2018
Revista Mexicana De Ciencias Geologicas, Aug 1, 2008
Historical Biology, May 12, 2020
ABSTRACT Recent palaeontological research in submerged caves of the north-eastern Yucatán Peninsu... more ABSTRACT Recent palaeontological research in submerged caves of the north-eastern Yucatán Peninsula (YP) in Mexico has resulted in the identification of a diverse megafaunal assemblage in the area, among them Late Pleistocene ground sloths assigned to the family Megalonychidae (Xenarthra). Here we report on a new species of Megalonychidae, Xibalbaonyx exinferis n. sp., from a new fossil locality named cenote Tortugas, located west of Puerto Morelos in the federal state of Quintana Roo. The taxon is based on a fragmentary left mandibular ramus, an atlas, and a left humerus. The new taxon is diagnosed by the presence of two mental foramina on the short symphyseal spout, a caniniform being the smallest mandibular tooth, and the anterolaterally directed aperture of the mandibular foramen on the lateral surface of the mandible. Xibalbaonyx exinferis is the third endemic megalonychid documented for the north-eastern Yucatán Peninsula and thus provides increasing evidence for an ecological isolation of the area from the rest of Mexico during the Pleistocene.
Journal of South American Earth Sciences, Aug 1, 2016
A coral-rich Berriasian unit locally known as the San Juan Lentil conforms the basal Taraises For... more A coral-rich Berriasian unit locally known as the San Juan Lentil conforms the basal Taraises Formation in the San Juan canyon located half distance between the cities of Saltillo and Monterrey in northeastern Mexico. Here we document the environmental conditions and discuss its regional distribution of this biostrome unit. Calpionellids are intermittently present and indicate a middle to late Berriasian age for the coral-bearing unit that was deposited during an interval of increased oligotrophic conditions.
Boletín de la Sociedad Geológica Mexicana, 2016
Five taxa of Kimmeridgian to Tithonian (Upper Jurassic) aptychi are here described from the La Ca... more Five taxa of Kimmeridgian to Tithonian (Upper Jurassic) aptychi are here described from the La Caja Formation of northeastern Mexico. Laevaptychus (Latuslaevaptychus) latus meyrati Trauth, 1931, L. (Hoplisuslaevaptychus) mexicanus (Castillo and Aguilera, 1895), L. (Autharislaevaptychus) favrei Trauth, 1931, Lamellaptychus lamellosus (Parkinson, 1811) and Lam. murocostatus Trauth, 1929 were previously known from the Tethyan Realm. In northeastern Mexico, records of Lamellaptychus are restricted to the upper lower Kimmeridgianlower upper Tithonian, while Laevaptychus is presently restricted to the uppermost Kimmeridgianuppermost Tithonian.
American Association of Petroleum Geologists eBooks, 2003
The Cretaceous sedimentary sequence at Punta Gorda in southern Belize corresponds only partially ... more The Cretaceous sedimentary sequence at Punta Gorda in southern Belize corresponds only partially to the known stratigraphic column of the Maya Block. In addition to dolomites and anhydrites of the Coban Formation (Aptian-Santonian), rudist-bearing shallow-water carbonates of the Campur Formation (Campanian-Maastrichtian), and the siliciclastic flysch sequence of the Sepur Formation (Maastrichtian-Eocene), pelagic limestones and limestones of debris-flow origin are present at Punta Gorda. They are of Berriasian-Valanginian and Aptian-Albian ages. Today, they are thrust onto dolomites of the Coban Formation and shales of the Sepur Formation. The pelagic limestones are similar in age and lithology to the sedimentary sequence of southwestern Cuba and suggest a common depositional area on the eastern margin of the Maya Block in the Proto-Caribbean Basin.
Journal of South American Earth Sciences, Aug 1, 2018
Here we describe the skull of a new species of Megaloychidae (Xenarthra) Xibalbaonyx microcaninus... more Here we describe the skull of a new species of Megaloychidae (Xenarthra) Xibalbaonyx microcaninus from the federal state of Jalisco in west-central Mexico based on a complete skull exhibited in the Museo Regional de Guadalajara (MRG). The specimen was originally collected in the Upper Pleistocene sediment of the Zacoalco paleolake (Jalisco) and is here assigned to the recently established genus Xibalbaonyx from the Late Pleistocene of Quintana Roo in southeastern Mexico. The genus Xibalbaonyx thus had a wider geographic distribution than previously considered and ranges from central to southern Mexico.
Palaeovertebrata, Jul 16, 2019
Boletín de la Sociedad Geológica Mexicana, 2017
Geodiversitas, Dec 15, 2022
couverture / cover : Réalisée à partir des Figures de l'article/Made from the Figures of the arti... more couverture / cover : Réalisée à partir des Figures de l'article/Made from the Figures of the article.
Palaeovertebrata, Jul 21, 2020
Uploads
Papers by wolfgang stinnesbeck