Dave Lovelace
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paleobadger.bsky.social
Dave Lovelace
@paleobadger.bsky.social
460 followers 180 following 92 posts
A Late Triassic vertebrate paleontologist in stratigraphers clothing (he/him), dad, partner, neurodivergent, with a love for woodworking and bluegrass. And cats. I also like cats.
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paleobadger.bsky.social
This kind of reconstruction would take a bit of time, and I am not sure if others have encountered this or not - any advice or thoughts on cost/benefit of 'rebuilding' these elements?

Just looking to croudsource some thoughts/experiences of others!
(2 of 2)
August 28, 2025 at 2:45 PM
paleobadger.bsky.social
Conclusion: Trace fossil evidence supports a global distribution of dinosauromorphs prior to the Carnian Pluvial Episode (234-232 Ma) and the oldest saurischian body fossils show a global distribution by ca 230 Ma. (fin)
Blue sky above an outcrop of mudstone that is purple in color. A tent-like structure is seen in the foreground and several people working on the outcrop are seen in distance. Two people prospecting for fossils on a purple and red mudstone outcrop
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
…are shared with the Popo Agie which adds a sauropodomorph and at least 2 rhynchosaurs (doi.org/10.3390/d150...) to a fauna that mirrors dinosaur-bearing faunas from Gondwana suggesting a more cosmopolitan distribution of these clades than previously recognized. (17/x)
Figure 10. Paleogeography of 12 Pangaean basins with Carnian-aged vertebrate assemblages (A) and the relative distribution of 11 clades (B) across north and south latitudes. Areal representation of Triassic strata exposed at Earth’s surface (macrostrat.org) (C) coincides with the total metazoan record for the entire Triassic (D), only the Carnian (E), and the Carnian amniote record (F). (PaleobioDB.org; accessed Feb, 2024; Supporting Information, Data S1). Four palaeobiogeographic maps demonstrate the spatial distribution of amniote clades that are: largely water bound (G), small bodied (H), or large bodied forms (I, J). Circles = present, blank = unknown, ? = uncertainties exist (age control, taxonomic status, etc.). Silhouettes from Phylopic.org; credits provided in Supporting Information, Text S1.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Recent work (doi.org/10.1130/B368...) supports a Carnian to Carnian-Norian boundary age for classic lower Dockum Group Otis Chalk quarries whose fauna includes the theropod dinosaur *Lepidus*, aetosaurs, and allokotosaurs. Silesaurs, *Buettnererpeton bakeri*, and *Parasuchus*...(16/x)
From Lovelace et al., 2024: https://doi.org/10.1130/B36807.1 Figure 8. Hypothesized chronostratigraphic relations of Late Triassic rocks in the Mountain West and High Plains, USA. Blue asterisklaser ablation–inductively coupled plasma–mass spectrometry; red asterisk—chemical abrasion–thermal ionization mass spectrometry. Cnty—County; Mb.—Member; PEFO—Petrified Forest National Park; Fm.—Formation; SS—sandstone.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
As part of this study we scanned the type specimen of *Lepidus* in order to digitally separate the astragalus from the distal tibia/fibula to observe previously hidden morphology which is now coded in our matrix. Resultant scan data and reconstructions are hosted on Morphosource,org, (15/x)
Fig. S5. 3D model from μCT scan (segmented in Dragonfly 2022.2) of the left astragalocalcaneum of Lepidus praecisio (TxVP41936-1; Loc. 41936, Dockum Site 7 general; Dockum Group; Triassic; collected by Works Progress). Orthographic views in (a) proximal (dorsal), (b) distal (ventral), (c) posterior, and (d) medial views.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
The presence of a silesaurid is not unexpected considering traces of *Atriepus*, commonly considered to represent dinosaur-like trace makers such as silesaurids, are known from early-mid Late Triassic strata around the globe, and now known from the Jelm FM a few m below the Popo Agie FM. (14/x)
Figure 5. UWGM 7435 (left) is an isolated slab containing a single tridactyl pes and possible manus impression attributed to an AtreipusGrallator plexus tracemaker from the upper Jelm Formation, Natrona County, WY, USA. A digital surface-depth map (right) produced in METASHAPE (v.2.0.3; Agisoft) from surface light-scans demonstrates the depth and toe pad delineations of pes (p) digits II–IV. The manus impression may be present (m?); other than a very slight depression there are no morphological features to confidently identify it as such. Scale bar is in 1-cm increments. Data reposited on Morphosource.org, ID: 000607578.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
We also report an indeterminate sulcimentasaurian silesaurid from the same site which is another first for the Popo Agie Fm (and possibly tied for oldest dinosaur in NA if you believe our phylogeny 😉). (13/x)
Figure 4. Photographs of sulcimentisaurian silesaurid elements from the Garrett’s Surprise locality. Distal end of a left humerus UWGM 7550 (A–E) in (A) anterior, (B) posterior, (C) medial, (D) lateral, (E) and distal views. Proximal end of a right femur UWGM 7407 (F–J) in (F) proximal, (G) anterolateral, (H) posteromedial, (I) posterolateral, and ( J) anteromedial views. Abbreviations: alt, anterolateral tuber; amt, anteromedial tuber; at, anterior trochanter; dlt, dorsolateral trochanter; ect, ectepicondyle; ent, entepicondyle; g, groove; gt, ‘greater trochanter;’ ipmt, incipient posteromedial tuber; n, notch; rc, radial condyle; uc, ulnar condyle. Arrows point in the anterior direction. Scale bar equals 1 cm.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Our character matrix is derived from work by Garcia and colleagues doi.org/10.1002/ar.2... which was selected for its wide taxonomic sample of early avemetatarsalians. Plus - we added some sauropodomorphs. Although silesaurids come out as early ornithischians, we remain agnostic. (11/x)
Figure 8. Strict consensus tree of avemetatarsalians and Euparkeria capensis using the combined OTU of Ahvaytum bahndooiveche obtained through maximum parsimony implemented in TNT v.1.5. The shaded interval (left) is the approximate duration of the Carnian Pluvial Episode (CPE), and the shaded interval (right) is the ‘Norian gap’ in the dinosaur record. Branches with filled in dots indicate northern hemisphere taxa and branches with hollow dots indicate southern hemisphere taxa. Dots at the end of branches are the approximate earliest occurrences of each taxon. For any higher taxon labels with two names, the latter name represents a widely used taxon that in the current analyses would be a junior synonym of the former. Statistical support values at nodes are: Bremer support decay indices/bootstrap resampling/jackknife resampling. All nodes with resampling values less than 15 indicate low support. Ahvaytum bahndooiveche and UWGM 7407+7550 are indicated in bold text. Figure 9. Consensus tree of avemetatarsalians and Euparkeria capensis using the combined OTU of Ahvaytum bahndooiveche obtained through Bayesian inference implemented in MrBayes v.3.2.6. The shaded interval (left) is the approximate duration of the Carnian Pluvial Episode (CPE), and the shaded interval (right) is the ‘Norian gap’ in the dinosaur record. Branches with filled in dots indicate northern hemisphere taxa and branches with hollow dots indicate southern hemisphere taxa. Dots at the end of branches are the approximate earliest occurrences of each taxon. For any higher taxon labels with two names, the latter name represents a widely used taxon that in the current analyses would be a junior synonym of the former. Statistical support values at nodes are posterior probabilities. All nodes with posterior probability < 0.5 were considered poorly supported and thus collapsed. The fully bifurcated tree can be found in Supporting Information, Fig. S3 in Text S1. Ahvaytum bahndooiveche and UWGM 7407+7550 are indicated in bold text.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Side note: Simms and Drost (2024) present data that shows karst deposits in the UK that produce *Thecodontosaurus, Pantydraco*, and *Pendraig* are dominantly Carnian in age, but precise age control on these specimens remains elusive doi.org/10.1016/j.pa... (10/x)
From the original paper: https://doi.org/10.1016/j.palaeo.2024.112041 Fig. 7. Triassic chronostratigraphy and radiometric dates (with 2σ errors) from Triassic caves at Cromhall and Garwa quarries. The coloured boxes represent the mean and 2σ errors for the flowstone samples. The approximate positions of the Carnian Pluvial Episode (CPE) and Penarth Group are indicated.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Our age constraint of ca. 230 Ma is supported by CA-ID-TIMS ages from youngest zircons recovered from 3 successive stratigraphic levels from the upper Popo Agie, well above the dinosaur site. An age model predicts *Ahvaytum* to be ca. 230 Ma, and the base of the Popo Agie to be ~ 231 Ma. (9/x)
Figure 6. U–Pb radioisotopic analyses of detrital zircons are represented as probability density plots (A) comparing tandem LA-ICP-MS and CA-ID-TIMS maximum depositional age results, kernel density estimates (B) with the youngest population highlighted (shaded bar), and concordia plots (C) for three samples (LA-ICPMS). Stratigraphic profile of Garrett’s Surprise (D) tied to an age-depth model using the R package ‘modifiedBchron’ (Methods) with predicted boundary ages (underlined) and maximum depositional ages for the Popo Agie Formation. Additional modeled ages incorporated an age-controlled Alcova LS as an anchor without (E) and with (F) a hiatal bound Jelm Formation. AL: Alcova Limestone, BS: Bell Springs Formation, NG: Nugget Formation.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
It is the oldest known North American dinosaur, and the oldest (with radioisotopic age-control) from the northern hemisphere. However, as reported in the article, we suggest there are several other contenders from the US & UK that are, at minimum, among the northern hemisphere’s oldest. (8/x)
(B) shows the relative stratigraphic positions for first occurrences of dinosaurian body and trace fossils tied to a generalized stratigraphic section (C) of the upper Chugwater Group [after Lovelace et al. (2024)]. The shaded box highlights the stratigraphic position of UWGM 1975 and UWGM 7407 within the Popo Agie Formation. Localities: 1, Argentina; 2, Brazil; 3, Zimbabwe; 4, India; 5, Germany; 6, Britain; 7, Morocco; 8, Texas, USA (Dockum Group); 9, south-western USA (Chinle/Moenkopi formations); 10, Wyoming, USA (Chugwater Group). Silhouettes (not to scale) on outcrop demonstrate faunal distribution within the Popo Agie and Jelm formations. At, Atreipus sp.; At–Gr, Atreipus–Grallator plexus; An, Anaschisma browni; Be, Beesiiwo cooowuse; Bu, Buettnererpeton bakeri; Br, Brachychirotherium sp.; Eu, Eubrachiosaurus browni; He, Heptasuchus clarki; Pa, Parasuchus bransoni; Po, Poposaurus gracilis; Ni, Ninumbeehan dookoodukah. Artist credits for silhouettes from Phylopic.org and abbreviated formation names provided in the Supporting Information, Text S1. Previously published dinosaur-bearing localities recovered from PBDB (PaleobioDB.org; accessed Feb, 2024; Supporting Information, Data S1).
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
We suggest the femur shows signs of osteological maturity implying this animal is near maximum body size which is fairly small. Not larger than Eoraptor. Thin section + images by Dr. K. Curry Rogers. (7/x)
Figure 7. Femoral histology of Ahvaytum bahndooiveche UWGM 1975 General view of femoral histology in (A) plane polarized light (PPL) and (B) cross-polarized light with a lambda compensator (XPL). Letters in (A) indicate positions of higher magnification photomicrographs (C–F). Anterior is toward the top in (A–B). Scale bar = 1 mm. C, PPL image of a thin, highly vascularized cortex (left) that surrounds an open medullary space (right) surrounded by thin bony trabeculae. Fibrolamellar primary cortical bone tissue is vascularized by irregular reticular and longitudinal primary osteons with occasional radial anastomoses. Scale bar = 500 microns. Rectangle indications position of image (D). D, XPL image highlighting secondary bone remodeling in the deep cortex indicated by the Internal Fundamental System (IFS). The IFS consists of layers of centripetally deposited, avascular lamellar fibered bone (LFB) lining the open medullary cavity. Scale bar = 300 microns. E, XPL image documenting the external primary cortex. Most of the preserved primary cortex is well vascularized fibrolamellar bone, dominated by longitudinal primary osteons with occasional circular anastomoses. A transition to more poorly vascularized lamellar fibered characterizes the most external cortex. Black rectangle indicates position of image (F) Scale bar = 500 microns. F, XPL image of the most superficial cortex. In this image the woven bone component of the fibrolamellar complex is indicated by pinker regions, while more organized LFB surrounds primary osteons, is layered at the periosteal surface, and is indicated by turquoise and orange regions. Scale bar = 150 microns.
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
We also refer a proximal femur from the site to *Ahvaytum* due to clear saurischian dinosaur affinities, but it does look a lot like *Chindesaurus*. Symplesiomorphies? Another taxon? We need more data! (6/x)
Figure 3. Proximal end of a left femur UWGM 7549 (A–E) referred to Ahvaytum bahndooiveche gen. et sp. nov.). 3D model in (A) anteromedial, (B) posterolateral, (C) proximal, (D) anterolateral, and (E) posteromedial orthographic views. Abbreviations: alt, anterolateral tuber; amt, anteromedial tuber; ce, concave emargination; dlt, dorsolateral trochanter; ft, fossa trochanterica (= facies articularis antitrochanterica); gt, ‘greater trochanter’; pmt, posteromedial tuber; ve, ventral emargination. Arrows indicate anterior direction. Scale bar = 1 cm. STL models archived online (morphosource.org ID: 000607572).
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
UWGM 1975: It’s not much to look at, but it’s arguably the most important ankle bone in the UW Geology Museum and is the holotype of *Ahvaytum bahndooiveche*’s. Cataloged and accessioned by @carriethecurator.bsky.social (5/x)
Figure 2. Holotype left astragalus of Ahvaytum bahndooiveche gen. et sp. nov. (UWGM 1975). 3D model in (A) medial, (B) lateral, (C) lateral transparent, (D) posterior transparent, (E) distal, (F) proximal, (I) anterior, and ( J) posterior orthographic views. Photographs in (G) proximal and (H) distal views. Abbreviations: amc, anteromedial corner; ap, ascending process of the astragalus; g, groove; f, foramen; ff, fibular facet; ldn, laterodistal notch (= lateroventral depression); mf, medial fossa; nf, non-articular fossa (= dorsal basin, = semi-elliptical fossa); p, platform; plp, posterolateral process; plr, posterolateral ridge; tf, tibial facet. Diagonal lines indicate broken surfaces. Arrows indicate anterior direction. Scale bar = 1 cm. STL models archived online (morphosource.org ID: 000607569).
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Our paper, “Rethinking dinosaur origins” was co-led by myself and @akufner.bsky.social, and co-authored by @adamfitch.bsky.social, Kristi Curry Rogers, Mark Schmitz, Darin Schwartz, @aleclairdiaz.bsky.social, Lynette St.Clair, Josh Mann, and Reba Teran. (2/x)
The title 'Rethinking dinosaur origins' is shown with authors and their institutional information
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
I am incredibly excited to share our new Open Access publication in the @zoojlinnsoc.bsky.social that was released today. Please welcome *Ahvaytum bahndooiveche*, a new species of sauropodomorph(?) dinosaur from the Popo Agie Formation, WY, USA. tinyurl.com/3zx7s3mx (1/x)
Image contains a small theropod dinosaur checking out a dead amphibian in a wetland forested ecosystem
January 8, 2025 at 3:38 AM
paleobadger.bsky.social
Post a picture you took (no description) to bring some zen to the timeline.
November 17, 2024 at 3:06 AM
paleobadger.bsky.social
I wanted to share this image of the type specimen of *Ninumbeehan dookoodukah* @calamanderso.bsky.social (bit.ly/3YTFep4) Prep was done by myself, and lab volunteer Brandon Price (a co-author on the paper). Note the tiny arm (posterior and ventral of the mandible)! #paleontology #geology #fossils
Fossil of the type specimen of Ninumbeehan dookoodukah from the upper Jelm Formation, WY. This fossil was named in Shoshone by the 2022 7th grade class from Fort Washakie School and Tribal Elders. The fossil shows a cone shaped amphibian skull ~ 6 cm in length, along with parts of the post crania still embedded in the burrow matrix it was preserved in.
November 15, 2024 at 4:04 PM
paleobadger.bsky.social
I wanted to share our paper describing a new estivating latiscopid amphibian species from the Late Triassic (mid-Carnian) of WY. *Ninumberhan* was named by 7th graders and tribal Elders from the Wind River Reservation. Art by @serpenillus.bsky.social

royalsocietypublishing.org/doi/10.1098/...
reconstruction of small 230+ million year old fossil sleep coming out of estivation burrow. one did not. 6 cm skull of fossil amphibian. burrows in situ.
November 10, 2024 at 4:13 PM