Cretaceous Research最新文献

Based on a well-preserved male specimen from mid-Cretaceous Kachin amber, we describe a new genus and its type species of earwig, Prodacnodes dupliforceps gen. et sp. nov. Prodacnodes has a unique combination of traits: large compound eyes, scape shorter than compound eye length, pronotum as broad as head, prosternum subtrapezoidal, wings present and fully developed, metatarsomere II not slanted apically, pygidium with short medioapical process, male external parameres with prominent subapical tooth mesally, and simple forceps. Our research contributes additional morphological features and information, enriching our comprehension of the lineages and diversity of Late Mesozoic earwigs.

The growth strategy of enantiornithine birds differs from other stem-group birds due to the slow and protracted growth phase that is usually recognized by the deposition of parallel-fibered bone, mostly avascular, and the appearance of resting line/s. In this study, we aimed to investigate the osteohistology of the miniature bohaiornithid-like enantiornithine bird Musivavis amabilis. The midshaft cortex of the left tibiotarsus of Musivavis consists of almost entirely avascular parallel-fibered bone; neither indicators of a faster growth period nor cessation growth marks are microscopically visible. To decipher the growth dynamics of this seemingly monotonous histostructure, made of relatively abundant osteocyte lacunae, we developed a new methodological algorithm in our laboratory and tested it. In principle, 2D-quantitative lacunar parameters were processed using statistical clustering methods to detect any transition between two different local densities of osteocyte lacunae. We found that the avascular cortical profiles of Musivavis exhibit a hidden pattern recording a short dynamic regime through a restricted transitional stage to gradually lowered dynamics in the distribution of the osteocyte lacunae. We conclude that novel mathematical tools are to be invented in studies of bone samples that look histologically simple as the substantial biological information can be overlooked by classic study approaches.

A new genus and species of Yuripopovinidae, Jinjupopovina eosahwae gen. et sp. nov. is described based on a piece of fragmentary fossil specimen from the lower Cretaceous Jinju Formation in Jinju City, South Korea. This species is the first record of Yuripopovinidae and the only heteropteran whose taxonomic status is reliably identified from the stratigraphic layer. Its antennal morphology provides a rare example of simultaneous enlargement in length and width among Heteroptera. Advantages and disadvantages of this antennal modification are discussed with references of other fossil and extant coreoids whose antennae are exaggerated. Our findings suggest that the antennae of Jinjupopovina facilitated visual signaling among infra-specific individuals or between reproductive partners. Evolutionary trends of the antennae in Yuripopovinidae are discussed with insights from Jinjupopovina.

Armadillosuchus arrudai, an extinct crocodyliform, has a complex pattern of tooth replacement. Replacement of functional teeth followed an alternating numerical and directional wave from posterior to anterior. Notably, the presence of an initial fossa in some teeth indicated root resorption and facilitated the development of tooth replacement. These aspects suggest a coordinated tooth replacement process, enabling the animal to maintain functional dentition. This study provides insights into the unique dental dynamics of Armadillosuchus arrudai, highlighting its lifelong polyphyodonty and the meaning of alternating replacement patterns. Microtomography allowed the comprehension of these intricate tooth replacement processes.

Docodonta are the most abundant and taxonomically diverse group of mammaliaforms in the high paleolatitude Lower Cretaceous Teete locality in Yakutia, Russia. Docodontans are represented by the tegotheriids Khorotherium yakutense and Ergetiis ichchi gen. et sp. nov., and possibly two more taxa known from fragmentary specimens (Docodonta indet.). Ergetiis ichchi gen. et sp. nov. shows a reduction and posterior shift of the angular process of the dentary which could indicate a reduction of the mandibular middle ear potentially in a way analogous to the transitional mammalian middle ear of Eutriconodonta. A revised phylogenetic analysis of Docodonta suggests a stemward position of Docodontidae and a sister group relationship for Simpsonodontidae and Tegotheriidae.

The fossil spider family Lagonomegopidae is widespread in the Cretaceous period, and mainly reported from mid-Cretaceous Kachin amber, northern Myanmar. Here, two new lagonomegopid species, belonging to the genus Lineaburmops, are described from Kachin amber: Lineaburmops longiantepes sp. nov. and Lineaburmops rhombus sp. nov., which showing similar contrasting body coloration as other Lineaburmops species. The compositional element of these special color patterns and their potential functions are discussed.

The Olmos Formation in Coahuila, Mexico has crucial information about the Cretaceous floras in northern Mexico. Its plant diversity is high and represents one of the most studied paleofloras for this region; angiosperm leaves are the main plant organs that can be found and serve as the primary source to reconstruct this paleoflora. Since a large part of the foliar diversity of this Formation has yet to be described, its documentation is essential to discuss further the history of plant establishment in southern North America. Through a detailed description and statistical comparison of its foliar architecture with other fossil and extant leaves, the new trilobate leaf is assigned to the fossil genus Pabiania Upchurch and Dilcher, a group found so far exclusively in the Cretaceous of the United States and now, for the first time in Mexico. Its leaf architecture suggests it is closely related to the Order Laurales and probably an extinct group within Lauraceae.

Here we report the associated and semi-articulated partial wing of a mid-sized pterosaur from an exposure of the Pierre Shale, in east central Wyoming. All elements suffer from compaction but are identified as those of a pteranodontid based on the warped deltopectoral crest. Most probably, the wing is that of Pteranodon longiceps, although the length of the ulna and of the metacarpal IV relative to that of the humerus slightly exceeds that reported from any previously documented Pteranodon specimen. The surfaces of all wing elements are littered with circular indentations, ranging from 1.1 to 6.8 mm in diameter. These indentations formed postmortem and appear to be borings left by invertebrate scavengers.

We wish to point out an obvious error made by one of us (J.F. Deconinck), and kindly reported by J.G. Bréhéret, the reason why we have jointly decided to publish this correction. The error affects at varying degrees the scientific quality and partly invalidates the conclusions of the following articles: Corentin et al. (2020) « Environmental and climatic controls of the clay mineralogy of Albian deposits in the Paris and Vocontian basins (France) » (Cretaceous Research, 108). and Ait-Itto et al. (2023) « Astronomical calibration of the OAE1b from the Col de Pré-Guittard section (Aptian–Albian) Vocontian Basin » (Cretaceous Research, 150).

Indeed, for the Vocontian basin, the analytical work, whatever its quality, was carried out on a stratigraphic interval which does not correspond to the presentation made. The two articles in question did not take into account the detailed lithostratigraphy and biostratigraphy earlier published, notably by Bréhéret (1997) and Bréhéret & Brumsack (2000) mentioning known marker beds as presented in these works. Thus, for one of the two sections, the displayed time window assumed to be the lower Albian, actually corresponds to a small part of the middle Albian and a part of the upper Albian. This invalidates many of the proposed results and conclusions.

Upper Tithonian to lower Berriasian carbonate sequence of the Getic Nappe System was studied near Golubac using an integrated biostratigraphy approach based on calpionellid, calcareous dinoflagellate, nannofossil, foraminifer, and palynomorph record. Calpionellids allowed subdivision of the section to standard calpionellid zones including the Colomi and Alpina subzones on the Tithonian–Berriasian transition. Nannofossil Nannoconus wintereri proves the presence of the NC0 Zone. Foraminifer fauna on the Tithonian–Berriasian transition contain zonal marker Globospirillina neocomiana and some other potential stratigraphic markers, whose range and taxonomy have to be fixed yet. Poor palynomorph spectra consist of long-ranging Lower-Cretaceous spores and pollen, and a few dinoflagellate cysts known from the Berriasian. Integrated biostratigraphy of the Tithonian–Berriasian oligotrophic open-marine carbonate facies of the Dedina section contributes to the stratigraphic framework necessary for the definition of the Berriasian Global Boundary Stratotype Section and Point.