Palaeohistology of Macrospondylus bollensis (Crocodylomorpha: Thalattosuchia: Teleosauroidea) from the Posidonienschiefer Formation (Toarcian) of Germany, with insights into life history and ecology DOI Creative Commons
Michela M. Johnson, Torsten M. Scheyer, Aurore Canoville

et al.

The Anatomical Record, Journal Year: 2024, Volume and Issue: 308(2), P. 342 - 368

Published: Sept. 28, 2024

Abstract The Posidonienschiefer Formation of southern Germany has yielded an array incredible fossil vertebrates. One the best represented clades therein is Teleosauroidea, a successful thalattosuchian crocodylomorph group that dominated coastlines. most abundant teleosauroid, Macrospondylus bollensis , known from wide range body sizes, making it ideal taxon for histological and ontogenetic investigations. Previous studies examining histology provide basic understanding bone microstructure in teleosauroids, but lack taxonomic, stratigraphic, control required to understand growth palaeobiology within species. Here, we examine three femora one tibia different‐sized M. individuals. We also perform compactness analyses evaluate ecological variation. Our results suggests (1) smallest specimen was young, skeletally immature individual with well‐vascularized‐parallel‐fibered limited remodeling midshaft periosteal cortex; (2) intermediate at death, vascularized parallel‐fibered tissue interrupted by least 10 LAGs, no clear external fundamental system (EFS), rather extensive inner cortical remodeling; (3) largest mature, numerous well‐developed EFS, deep cortex. grew relatively regularly until reaching adult size, global values fall reported modern crocodylians. lifestyle inference models used suggest well adapted aquatic environment retained some ability move on land. Finally, both larger specimens display peculiar, localized area disorganized interpreted as pathological.

Language: Английский

A review of the non‐semiaquatic adaptations of extinct crocodylomorphs throughout their fossil record DOI Open Access
Yohan Pochat‐Cottilloux

The Anatomical Record, Journal Year: 2024, Volume and Issue: 308(2), P. 266 - 314

Published: Nov. 25, 2024

Abstract Crocodylomorphs constitute a clade of archosaurs that have thrived since the Mesozoic until today and survived numerous major biological crises. Contrary to historic belief, their semiaquatic extant representatives (crocodylians) are not living fossils, and, during evolutionary history, crocodylomorphs evolved live in variety environments. This review aims summarize non‐semiaquatic adaptations (i.e., either terrestrial or fully aquatic) different groups from periods, highlighting how exactly those lifestyles inferred for animals, with regard geographic temporal distribution phylogenetic relationships. The ancestral condition Crocodylomorpha seems been lifestyle, linked several morphological such as an altirostral skull, long limbs allowing erect posture specialized dentition diets based on land. However, some members this clade, thalattosuchians dyrosaurids display opposite, aquatic interestingly same type observations. Finally, new techniques inferring paleobiology extinct animals put forward last decade, appearing complementary approach traditional descriptions comparisons. Such is case paleoneuroanatomical (CT scan data), histological, geochemical studies.

Language: Английский

Citations

4
Life history and growth dynamics of a peirosaurid crocodylomorph (Mesoeucrocodylia; Notosuchia) from the Late Cretaceous of Argentina inferred from its bone histology DOI Open Access
Tamara G. Navarro, Ignacio A. Cerda, Leonardo Filippi

et al.

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 23, 2025

Abstract Notosuchia were a successful lineage of Crocodyliformes that achieved remarkable diversity during the Cretaceous Gondwana, particularly in South America. Although paleohistology has expanded our knowledge paleobiology notosuchians, several clades this remain poorly understood aspect. Here we help to address gap by conducting first histological analysis appendicular bones peirosaurid. To increase about growth dynamics and examine intraeskeletal interspecific variation, analyze microstructure tibia, fibula, phalanx, fragment ornamented element (possible osteoderm or skull bone) possible long bone an individual assigned Peirosauridae indet. (MAU‐Pv‐437). The peirosaurid studied here appears have reached sexual but not somatic maturity minimum age inferred from results lower estimated than osteoderms previous study on same individual. cortical MAU‐Pv 437 is formed vascularized parallel fibered bone/lamellar which indicates experienced moderate rate. This different what been observed for other notosuchians specimens, suggesting lack uniform pattern clade.

Language: Английский

Citations

0
Palaeohistology of Macrospondylus bollensis (Crocodylomorpha: Thalattosuchia: Teleosauroidea) from the Posidonienschiefer Formation (Toarcian) of Germany, with insights into life history and ecology DOI Creative Commons
Michela M. Johnson, Torsten M. Scheyer, Aurore Canoville

et al.

The Anatomical Record, Journal Year: 2024, Volume and Issue: 308(2), P. 342 - 368

Published: Sept. 28, 2024

Abstract The Posidonienschiefer Formation of southern Germany has yielded an array incredible fossil vertebrates. One the best represented clades therein is Teleosauroidea, a successful thalattosuchian crocodylomorph group that dominated coastlines. most abundant teleosauroid, Macrospondylus bollensis , known from wide range body sizes, making it ideal taxon for histological and ontogenetic investigations. Previous studies examining histology provide basic understanding bone microstructure in teleosauroids, but lack taxonomic, stratigraphic, control required to understand growth palaeobiology within species. Here, we examine three femora one tibia different‐sized M. individuals. We also perform compactness analyses evaluate ecological variation. Our results suggests (1) smallest specimen was young, skeletally immature individual with well‐vascularized‐parallel‐fibered limited remodeling midshaft periosteal cortex; (2) intermediate at death, vascularized parallel‐fibered tissue interrupted by least 10 LAGs, no clear external fundamental system (EFS), rather extensive inner cortical remodeling; (3) largest mature, numerous well‐developed EFS, deep cortex. grew relatively regularly until reaching adult size, global values fall reported modern crocodylians. lifestyle inference models used suggest well adapted aquatic environment retained some ability move on land. Finally, both larger specimens display peculiar, localized area disorganized interpreted as pathological.

Language: Английский

Citations

2