1
|
Ledesma DT, Scarpetta SG, Jacisin JJ, Meza A, Kemp ME. Identification of Late Pleistocene and Holocene fossil lizards from Hall's Cave (Kerr County, Texas) and a primer on morphological variation in North American lizard skulls. PLoS One 2024; 19:e0308714. [PMID: 39146299 PMCID: PMC11326655 DOI: 10.1371/journal.pone.0308714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2023] [Accepted: 07/29/2024] [Indexed: 08/17/2024] Open
Abstract
Fossil identification practices have a profound effect on our interpretation of the past because these identifications form the basis for downstream analyses. Therefore, well-supported fossil identifications are necessary for examining the impact of past environmental changes on populations and communities. Here we apply an apomorphic identification framework in a case study identifying fossil lizard remains from Hall's Cave, a late Quaternary fossil site located in Central Texas, USA. We present images and descriptions of a broad comparative sample of North American lizard cranial elements and compile new and previously reported apomorphic characters for identifying fossil lizards. Our fossil identifications from Hall's Cave resulted in a minimum of 11 lizard taxa, including five lizard taxa previously unknown from the site. Most of the identified fossil lizard taxa inhabit the area around Hall's Cave today, but we reinforce the presence of an extirpated species complex of horned lizard. A main goal of this work is to establish a procedure for making well-supported fossil lizard identifications across North America. The data from this study will assist researchers endeavoring to identify fossil lizards, increasing the potential for novel discoveries related to North American lizards and facilitating more holistic views of ancient faunal assemblages.
Collapse
Affiliation(s)
- David T Ledesma
- Department of Integrative Biology, The University of Texas, Austin, Texas, United States of America
| | - Simon G Scarpetta
- Department of Integrative Biology, Museum of Vertebrate Zoology, University of California Berkeley, Berkeley, California, United States of America
| | - John J Jacisin
- Department of Integrative Biology, The University of Texas, Austin, Texas, United States of America
| | - Antonio Meza
- Department of Integrative Biology, The University of Texas, Austin, Texas, United States of America
| | - Melissa E Kemp
- Department of Integrative Biology, The University of Texas, Austin, Texas, United States of America
| |
Collapse
|
2
|
Brownstein CD, Simões TR, Caldwell MW, Lee MSY, Meyer DL, Scarpetta SG. The affinities of the Late Triassic Cryptovaranoides and the age of crown squamates. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230968. [PMID: 37830017 PMCID: PMC10565374 DOI: 10.1098/rsos.230968] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Accepted: 09/18/2023] [Indexed: 10/14/2023]
Abstract
Most living reptile diversity is concentrated in Squamata (lizards, including snakes), which have poorly known origins in space and time. Recently, †Cryptovaranoides microlanius from the Late Triassic of the United Kingdom was described as the oldest crown squamate. If true, this result would push back the origin of all major lizard clades by 30-65 Myr and suggest that divergence times for reptile clades estimated using genomic and morphological data are grossly inaccurate. Here, we use computed tomography scans and expanded phylogenetic datasets to re-evaluate the phylogenetic affinities of †Cryptovaranoides and other putative early squamates. We robustly reject the crown squamate affinities of †Cryptovaranoides, and instead resolve †Cryptovaranoides as a potential member of the bird and crocodylian total clade, Archosauromorpha. Bayesian total evidence dating supports a Jurassic origin of crown squamates, not Triassic as recently suggested. We highlight how features traditionally linked to lepidosaurs are in fact widespread across Triassic reptiles. Our study reaffirms the importance of critically choosing and constructing morphological datasets and appropriate taxon sampling to test the phylogenetic affinities of problematic fossils and calibrate the Tree of Life.
Collapse
Affiliation(s)
- Chase D. Brownstein
- Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06511, USA
- Stamford Museum and Nature Center, Stamford, CT 06903, USA
| | - Tiago R. Simões
- Department of Organismic and Evolutionary Biology & Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA
- Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA
| | - Michael W. Caldwell
- Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada
- Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada
| | - Michael S. Y. Lee
- College of Science and Engineering, Flinders University, Adelaide 5001, Australia
- Earth Sciences Section, South Australian Museum, North Terrace, Adelaide 5000, Australia
| | - Dalton L. Meyer
- Department of Earth and Planetary Sciences, Yale University, New Haven, CT 06511, USA
| | - Simon G. Scarpetta
- Museum of Vertebrate Zoology, Department of Integrative Biology, University of California, Berkeley, CA 94720, USA
- Department of Environmental Science, University of San Francisco, San Francisco, CA 94117, USA
| |
Collapse
|
3
|
Pauwels OSG, DAS S, Camara LB, Chirio L, Doumbia J, D'Acoz CD, Dufour S, Margraf N, Sonet G. Rediscovery, range extension, phylogenetic relationships and updated diagnosis of the Ornate Long-tailed Lizard Latastia ornata Monard, 1940 (Squamata: Lacertidae). Zootaxa 2023; 5296:501-524. [PMID: 37518430 DOI: 10.11646/zootaxa.5296.4.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Indexed: 08/01/2023]
Abstract
The lacertid Latastia ornata was known to date only by its holotype collected in 1938 in Bafatá, central Guinea-Bissau. We report new specimens and localities from Guinea-Conakry, a new country record and major range extension of 700 km SE of the type-locality. We provide an updated diagnosis of the species, including the first genetic and osteological data, and confirm that Latastia ornata is closely related to, but distinct from, L. longicaudata based on external morphology, cranial osteology, DNA data and zoogeography.
Collapse
Affiliation(s)
| | - Sunandan DAS
- Ecological Genetics Research Unit; Organismal and Evolutionary Biology Research Programme; Faculty of Biological and Environmental Sciences; FI-00014 University of Helsinki.
| | - Lewei Boyo Camara
- Sylvatrop Consulting; Immeuble PITA; Cité du Chemin de Fer; Conakry.
| | | | - Joseph Doumbia
- Sylvatrop Consulting; Immeuble PITA; Cité du Chemin de Fer; Conakry.
| | | | - Sylvain Dufour
- Sylvatrop Consulting; Immeuble PITA; Cité du Chemin de Fer; Conakry.
| | - Nicolas Margraf
- MUZOO; Musée d'histoire naturelle de La Chaux-de-Fonds; Neuchâtel.
| | - Gontran Sonet
- OD Taxonomy and Phylogeny; Royal Belgian Institute of Natural Sciences.
| |
Collapse
|
4
|
Brownstein CD, Meyer DL, Fabbri M, Bhullar BAS, Gauthier JA. Evolutionary origins of the prolonged extant squamate radiation. Nat Commun 2022; 13:7087. [PMID: 36446761 PMCID: PMC9708687 DOI: 10.1038/s41467-022-34217-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Accepted: 10/18/2022] [Indexed: 11/30/2022] Open
Abstract
Squamata is the most diverse clade of terrestrial vertebrates. Although the origin of pan-squamates lies in the Triassic, the oldest undisputed members of extant clades known from nearly complete, uncrushed material come from the Cretaceous. Here, we describe three-dimensionally preserved partial skulls of two new crown lizards from the Late Jurassic of North America. Both species are placed at the base of the skink, girdled, and night lizard clade Pan-Scincoidea, which consistently occupies a position deep inside the squamate crown in both morphological and molecular phylogenies. The new lizards show that several features uniting pan-scincoids with another major lizard clade, the pan-lacertoids, in trees using morphology were convergently acquired as predicted by molecular analyses. Further, the palate of one new lizard bears a handful of ancestral saurian characteristics lost in nearly all extant squamates, revealing an underappreciated degree of complex morphological evolution in the early squamate crown. We find strong evidence for close relationships between the two new species and Cretaceous taxa from Eurasia. Together, these results suggest that early crown squamates had a wide geographic distribution and experienced complicated morphological evolution even while the Rhynchocephalia, now solely represented by the tuatara, was the dominant clade of lepidosaurs.
Collapse
Affiliation(s)
- Chase D. Brownstein
- grid.47100.320000000419368710Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT USA ,Stamford Museum and Nature Center, Stamford, CT USA
| | - Dalton L. Meyer
- grid.47100.320000000419368710Department of Earth and Planetary Sciences, Yale University, New Haven, CT USA
| | - Matteo Fabbri
- grid.47100.320000000419368710Department of Earth and Planetary Sciences, Yale University, New Haven, CT USA ,grid.299784.90000 0001 0476 8496Negaunee Integrative Research Center, Field Museum of Natural History, Chicago, IL USA
| | - Bhart-Anjan S. Bhullar
- grid.47100.320000000419368710Department of Earth and Planetary Sciences, Yale University, New Haven, CT USA ,grid.47100.320000000419368710Yale Peabody Museum, Yale University, New Haven, CT USA
| | - Jacques A. Gauthier
- grid.47100.320000000419368710Department of Earth and Planetary Sciences, Yale University, New Haven, CT USA ,grid.47100.320000000419368710Yale Peabody Museum, Yale University, New Haven, CT USA
| |
Collapse
|
5
|
Scarpetta SG, Ledesma DT, Bell CJ. A new extinct species of alligator lizard (Squamata: Elgaria) and an expanded perspective on the osteology and phylogeny of Gerrhonotinae. BMC Ecol Evol 2021; 21:184. [PMID: 34587907 PMCID: PMC8482661 DOI: 10.1186/s12862-021-01912-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2021] [Accepted: 09/15/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alligator lizards (Gerrhonotinae) are a well-known group of extant North American lizard. Although many fossils were previously referred to Gerrhonotinae, most of those fossils are isolated and fragmentary cranial elements that could not be placed in a precise phylogenetic context, and only a handful of known fossils are articulated skulls. The fossil record has provided limited information on the biogeography and phylogeny of Gerrhonotinae. RESULTS We redescribe a nearly complete articulated fossil skull from the Pliocene sediments of the Anza-Borrego Desert in southern California, and refer the specimen to the alligator lizard genus Elgaria. The fossil is a representative of a newly described species, Elgaria peludoverde. We created a morphological matrix to assess the phylogeny of alligator lizards and facilitate identifications of fossil gerrhonotines. The matrix contains a considerably expanded taxonomic sample relative to previous morphological studies of gerrhonotines, and we sampled two specimens for many species to partially account for intraspecific variation. Specimen-based phylogenetic analyses of our dataset using Bayesian inference and parsimony inferred that Elgaria peludoverde is part of crown Elgaria. The new species is potentially related to the extant species Elgaria kingii and Elgaria paucicarinata, but that relationship was not strongly supported, probably because of extensive variation among Elgaria. We explored several alternative biogeographic scenarios implied by the geographic and temporal occurrence of the new species and its potential phylogenetic placements. CONCLUSIONS Elgaria peludoverde is the first described extinct species of Elgaria and provides new information on the biogeographic history and diversification of Elgaria. Our research expands the understanding of phylogenetic relationships and biogeography of alligator lizards and strengthens the foundation of future investigations. The osteological data and phylogenetic matrix that we provided will be critical for future efforts to place fossil gerrhonotines. Despite limited intraspecific sampled sizes, we encountered substantial variation among gerrhonotines, demonstrating the value of exploring patterns of variation for morphological phylogenetics and for the phylogenetic placement of fossils. Future osteological investigations on the species we examined and on species we did not examine will continue to augment our knowledge of patterns of variation in alligator lizards and aid in phylogenetics and fossil placement.
Collapse
Affiliation(s)
- Simon G Scarpetta
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, USA.
| | - David T Ledesma
- Department of Integrative Biology, The University of Texas at Austin, Austin, USA
| | - Christopher J Bell
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, USA
| |
Collapse
|
6
|
Ledesma DT, Scarpetta SG, Bell CJ. Variation in the skulls of Elgaria and Gerrhonotus (Anguidae, Gerrhonotinae) and implications for phylogenetics and fossil identification. PeerJ 2021; 9:e11602. [PMID: 34327052 PMCID: PMC8310624 DOI: 10.7717/peerj.11602] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Accepted: 05/21/2021] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND There are limited data on intra- and interspecific osteological variation for many squamate clades. Those data are relevant for phylogenetic analyses that use osteological characters and for apomorphic identifications of fossils. We investigate whether morphological features in the skulls of extant gerrhonotine lizards can be used to distinguish taxa at the species- and genus-level and assess whether newly discovered intra- and interspecific osteological variation alters the utility of previously reported apomorphic features. We examined skulls of species belonging to the gerrhonotine genera Elgaria and Gerrhonotus. These genera contain 17 extant species, but the cranial osteology of only a few species was previously examined. As a result, intra- and interspecific osteological variation of these gerrhonotines is poorly understood. METHODS We employed high-resolution x-ray computed tomography (CT) to scan 25 alcohol-preserved specimens. We provide data on the skulls of all eight species of Elgaria, four for the first time, and five species of Gerrhonotus, three for the first time. We examined 3-D reconstructed skulls of the scanned specimens as well as dry, traditionally prepared skeletons (when they were available). RESULTS We found that the purported diagnostic utility of many previously described morphological features is impacted because of substantial morphological variation between and within species. We present an assessment of osteological differences that may be useful to differentiate species of Elgaria and Gerrhonotus, many of which are present on isolated cranial elements commonly recovered as fossils, including the premaxilla, maxilla, parietal, pterygoid, prootic, dentary, and surangular. We demonstrate the importance of documenting patterns of osteological variation using large sample sizes, and the utility of examining disarticulated cranial elements of the squamate skull to identify diagnostic morphology. This study adds to a growing body of literature suggesting that extensive documentation of morphological variation is needed to further our understanding of the phylogenetic and diagnostic utility of morphological features across vertebrate clades. Efforts in that direction likely will benefit from examination of disarticulated skeletal elements.
Collapse
Affiliation(s)
- David T. Ledesma
- Department of Integrative Biology, The University of Texas at Austin, Austin, Texas, United States
| | - Simon G. Scarpetta
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas, United States
| | - Christopher J. Bell
- Department of Geological Sciences, Jackson School of Geosciences, The University of Texas at Austin, Austin, Texas, United States
| |
Collapse
|
7
|
Ősi A, Magyar J, Rosta K, Vickaryous M. Cranial ornamentation in the Late Cretaceous nodosaurid ankylosaur Hungarosaurus. PeerJ 2021; 9:e11010. [PMID: 33717709 PMCID: PMC7936564 DOI: 10.7717/peerj.11010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Accepted: 02/04/2021] [Indexed: 11/20/2022] Open
Abstract
Bony cranial ornamentation is developed by many groups of vertebrates, including ankylosaur dinosaurs. To date, the morphology and ontogenetic origin of ankylosaurian cranial ornamentation has primarily focused on a limited number of species from only one of the two major lineages, Ankylosauridae. For members of the sister group Nodosauridae, less is known. Here, we provide new details of the cranial anatomy of the nodosaurid Hungarosaurus from the Santonian of Europe. Based on a number of previously described and newly identified fragmentary skulls and skull elements, we recognize three different size classes of Hungarosaurus. We interpret these size classes as representing different stages of ontogeny. Cranial ornamentation is already well-developed in the earliest ontogenetic stage represented herein, suggesting that the presence of outgrowths may have played a role in intra- and interspecific recognition. We find no evidence that cranial ornamentation in Hungarosaurus involves the contribution of coossified osteoderms. Instead, available evidence indicates that cranial ornamentation forms as a result of the elaboration of individual elements. Although individual differences and sexual dimorphism cannot be excluded, the observed variation in Hungarosaurus cranial ornamentation appears to be associated with ontogeny.
Collapse
Affiliation(s)
- Attila Ősi
- Department of Paleontology, Eötvös Loránd University, Budapest, Hungary.,Hungarian Natural History Museum, Budapest, Hungary
| | - János Magyar
- Department of Paleontology, Eötvös Loránd University, Budapest, Hungary
| | - Károly Rosta
- Department of Paleontology, Eötvös Loránd University, Budapest, Hungary
| | | |
Collapse
|