[Paleontology • 2024] Terastiodontosaurus marcelosanchezi • The World’s Largest Worm Lizard: A New giant trogonophid (Squamata: Amphisbaenia) with extreme Dental Adaptations from the Eocene of Chambi, Tunisia

 

Terastiodontosaurus marcelosanchezi Georgalis & Smith, 

in Georgalis, Smith, Marivaux, Herrel, Essid, Ammar, Marzougui, Temani et Tabuce, 2024.

DOI: doi.org/10.1093/zoolinnean/zlae133

Artwork by Jaime Chirinos.

Abstract

We here describe Terastiodontosaurus marcelosanchezi, a new amphisbaenian genus and species from the Eocene of Chambi, Tunisia. Using micro-computed tomography (μCT), we document the peculiar anatomy of the new taxon, which is characterized by extreme dental morphology, including one massive tooth on the maxilla and dentary, flat cheek teeth, and an array of other diagnostic features that readily differentiate it from all other amphisbaenians. We also redescribe the oldest named African amphisbaenian, Todrasaurus gheerbranti, from the late Palaeocene of Morocco, using μCT. Phylogenetic analysis recovers Terastiodontosaurus and Todrasaurus as sister taxa and provides strong support for a sister-group relationship of those two large-toothed amphisbaenians with extant Trogonophis. Accordingly, Todrasaurus shows that the divergence of crown Trogonophidae occurred much earlier than currently thought. Our survey of μCT scans reveals that Terastiodontosaurus, Todrasaurus, and Trogonophis are characterized by a great enamel thickness on their teeth, a feature that is absent in other examined amphisbaenians. Size estimates show that Terastiodontosaurus was the largest known amphisbaenian ever to have lived, with an estimated skull length of >5 cm. Based on new muscle data of Trogonophis, we estimate very high bite forces for Terastiodontosaurus, which would allow it to crush a wide variety of snails.

new genus and species, Palaeogene, North Africa, phylogenetic analysis, bite force, size, autecology

Systematic palaeontology

Squamata Oppel 1811,

Amphisbaenia Gray, 1844,

Trogonophidae Bonaparte, 1838

Figure 2.Holotype right maxilla (ONM CBI-1-645) of Terastiodontosaurus marcelosanchezi. Photographs of the specimen in labial (A), medial (B), dorsal (C), and ventral (D) views.

Terastiodontosaurus Georgalis & Smith gen. nov.

 

Etymology: The genus name derives from the Greek words ‘τεράστιος’ (‘terastios’), meaning ‘huge’/‘enormous’, ‘ὀδούς’ [in genitive: ‘ὀδόντος’ (‘odontos’)], meaning ‘tooth’, and ‘σαύρα’ (‘saura’), meaning ‘lizard’. The gender of the new genus name is masculine.

 Terastiodontosaurus marcelosanchezi Georgalis & Smith gen. et sp. nov.

Etymology: The species epithet is named after Professor Marcelo Sánchez-Villagra, director of the Palaeontological Institute of the University of Zurich, as an honour for his major contributions to palaeontology, zoology, and evolutionary biology, in addition to the kind friendship and his great support to the first author (G.L.G.) for many years.

Diagnosis:

Terastiodontosaurus marcelosanchezi can be referred to Amphisbaenia based on the prominent and enlarged median premaxillary tooth, the large anterior premaxillary foramina, the low tooth count on the maxilla and dentary, the ventral extension of the mandibular symphysis below Meckel’s groove, the broad insertion fossa for mandibular adductor muscles on the posterolateral surface of the dentary, and the strong and elevated coronoid process of the dentary. Terastiodontosaurus marcelosanchezi can be referred to Trogonophidae based on the presence of acrodont dentition, closely appressed (‘fused’) teeth, the interdigitating suture between the frontal and the facial process of the maxilla, and ectopterygoid abutting the posteromedial corner of the maxilla.

Terastiodontosaurus marcelosanchezi is united with Trogonophis wiegmanni by: thick enamel on marginal teeth, and ‘twinning’ of paired premaxillary teeth, with median tooth separated by a diastema from paired teeth. Terastiodontosaurus marcelosanchezi is united with Todrasaurus gheerbranti by: thick enamel on marginal teeth, extremely enlarged (>60% longer than ...

 

Type locality and horizon: Chambi 1 (CBI-1), Djebel Chambi, Kassérine region, western part of Central Tunisia, Tunisia; late early to early middle Eocene (late Ypresian to early Lutetian).

 

Life reconstruction of Terastiodontosaurus marcelosanchezi ready to prey on a large snail of the family Bulimulidae.

Artwork by Jaime Chirinos.

Georgios L Georgalis, Krister T Smith, Laurent Marivaux, Anthony Herrel, El Mabrouk Essid, Hayet Khayati Ammar, Wissem Marzougui, Rim Temani and Rodolphe Tabuce. 2024. The World’s Largest Worm Lizard: A New giant trogonophid (Squamata: Amphisbaenia) with extreme Dental Adaptations from the Eocene of Chambi, Tunisia. Zoological Journal of the Linnean Society. 202(3), zlae133. DOI: doi.org/10.1093/zoolinnean/zlae133

  x.com/DrGeorgalis/status/1859636240070373793

[Botany • 2020] Limonium steppicum (Plumbaginaceae) • A New Species of Limonium from Tunisia

Limonium steppicum Sefi, Ghrabi-Gammar & Brullo

in Sefi, Ghrabi-Gammar, Jilani, Daoud-Bouattour & Brullo, 2020. 

DOI: 10.11646/phytotaxa.446.5.1 

Researchgate.net/publication/341881120 

Abstract

Limonium steppicum, a new species is described and illustrated from the Island of Djerba in Tunisia, where it is localized at the edges of salt marshes in very dry environmental conditions. Morphologically, it is closely related to L. rubescens, widespread in southern Tunisia, from which it is differentiated in many morphological features and also for its ecological requirements.

Keywords: Djerba, Endemic, Mediterranean flora, sea lavender, Eudicots

FIGURE 1. Diagnostic features of Limonium steppicum Sefi, Ghrabi-Gammar & Brullo.
A. Habit. B. Inflorescence. C. Spikelet. D. Inner bract, lateral view. E. Inner

Limonium steppicum Sefi, Ghrabi-Gammar & Brullo sp. nov. 

A Limonio rubescentis foliis 3–5 nervis, evidenter mucronatis, scapo max. 60 cm alto, ramulis inflorescentiae paucis, spicis brevioribus, densis, spiculis 4,5–5 mm longis, 5–8 floris, ad 9–10 in 1 cm dispositis, bractea inferiori 1,8–2 mm longa, ovata, bractea media rotundata, bractea interiori 3–3,5 mm longa, ovata, acumine 0,8–1 mm longo, calyce 3,1–3,4 mm longo, tubo sparsim puberulo, lobis ovatis, 0,5–0,6 mm longis, costis superantibus basi loborum differt.  

Ons Sefi, Zeineb Ghrabi-Gammar, Imtinen Ben Haj Jilani, Amina Daoud-Bouattour and Salvatore Brullo. 2020. A New Species of Limonium from Tunisia. Phytotaxa. 446(5); 281–290. DOI: 10.11646/phytotaxa.446.5.1 

Researchgate.net/publication/341881120_A_new_species_of_Limonium_from_Tunisia

[Paleontology • 2016] Machimosaurus rex • The Largest Thalattosuchian (Crocodylomorpha) supports Teleosaurid Survival Across the Jurassic-Cretaceous Boundary

Machimosaurus rex Fanti, Miyashita, Cantelli, Mnasri, Dridi, Contessi & Cau, 2016

Life reconstruction: Davide Bonadonna theropoda.blogspot.com
 DOI: 10.1016/j.cretres.2015.11.011 

Fig. 8. Comparison among skulls of Machimosaurus.
 (A) holotype of M. buffetauti, (B) neotype of M. mosae, (C) estimated size of the ‘Leira specimen’ of M. hugii,
 (D) holotype of Machimosaurus rex. Dashed areas in (A) and (B) indicate size of largest known individuals of those species.
(E) Reconstruction of Machimosaurus rex body based on preserved elements.

Figures (A)–(C) modified from Young et al. (2014b).  DOI: 10.1016/j.cretres.2015.11.011  

Highlights

• Machimosaurus rex is a new teleosaurid crocodylomorph from Tunisia.

• It is the largest known thalattosuchian, up to 10 m in length.

• M. rex, the first Cretaceous teleosauroid found, was the last-surviving of its group.

Abstract

A new teleosaurid from the Lower Cretaceous of Tataouine (Tunisia), Machimosaurus rex sp. nov., definitively falsifies that these crocodylomorphs faced extinction at the end of the Jurassic. Phylogenetic analysis supports its placement closer to M. hugii and M. mosae than M. buffetauti. With the skull length up to 160 cm and an estimated body length of 10 m, M. rex results the largest known thalattosuchian, and the largest known crocodylomorph at its time. This giant thallatosuchian probably was an ambush predator in the lagoonal environments that characterized the Tethyan margin of Africa during the earliest Cretaceous. Whether the Jurassic-Cretaceous mass extinction was real or artefact is debated. The discovery of M. rex supports that the end-Jurassic crisis affected primarily Laurasian biota and its purported magnitude is most likely biased by the incomplete Gondwanan fossil record. The faunal turnovers during the J-K transition are likely interpreted as local extinction events, triggered by regional ecological factors, and survival of widely-distributed and eurytypic forms by means of habitat tracking.

Keywords: Lower Cretaceous; Machimosaurus; Teleosauridae; Thalattosuchia; Tunisia

Systematic paleontology

Crocodylomorpha Hay, 1930

Thalattosuchia Fraas, 1901

Teleosauridae Saint-Hilaire, 1831

Machimosaurus von Meyer, 1837

Machimosaurus rex sp. nov.

(ZooBank code: LSID urn:lsid:zoobank.org:act:1A11E9B9-0B1C-4557-92B7-165168658C17)

Etymology. The species name rex, Latin for “king”, refers to its majestic size among known Machimosaurus and all thalattosuchians.

Holotype. ONM NG NG 1–25, 80, 81, and 83–87

( Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6 and Fig. 7D; Table 1).

Fig. 4. Machimosaurus rex type skull,
(A) in situ photograph showing dorsally exposed preserved bones, (B) prepared ventral surface.

Abbreviations: fr, frontal; lj, left jugal; la, lacrimal; ld, left dentary; lmx, left maxilla; lna, left nasal; lpd, left postdentary elements; lposq, left postorbitalsquamosal bar; os, osteoderm; pa, palatal element; rd, right dentary; rmx, right maxilla; rna, right nasal; rpd, right postdentary elements; rposq, right postorbital-squamosal bar; stfo, floor of supratemporal fossa; tp, turtle plastron element. Scale bar = 50 cm.

  DOI: 10.1016/j.cretres.2015.11.011 

Locality and horizon. Touil el Mhahir, Tataouine Governorate, Tunisia; Douiret Sand Member, Douiret Formation, Hauterivian, Lower Cretaceous.

Fig. 1. (A) Geographic location and type locality of Machimosaurus rex. (B) Simplified geological map of the Tataouine basin of southern Tunisia showing the Touil el Mhahir locality.

DOI: 10.1016/j.cretres.2015.11.011 

Diagnosis. Teleosaurid differing from other species by unique combination of: adult basicranial length >155 cm ( Fig. 5); rostrum ornamented by densely arranged, parallel longitudinal ridges; orbit elliptical; interorbital space narrow (one fifth length of skull posterior to orbit); anteromedial margin of supratemporal fossae round; frontal not extended anteriorly to orbit and with reduced orbital margin; relatively large maxillary alveoli; anterior dorsal neural spine height less than centrum height; dorsal osteoderms with tightly packed pits that are round centrally and ellipsoid peripherally.

Fig. 8. Comparison among skulls of Machimosaurus
(A) holotype of M. buffetauti, (B) neotype of M. mosae, (C) estimated size of the ‘Leira specimen’ of M. hugii, (D) holotype of Machimosaurus rex. Dashed areas in (A) and (B) indicate size of largest known individuals of those species. (E) Reconstruction of Machimosaurus rex body based on preserved elements.

Figures (A)–(C) modified from Young et al. (2014b).  DOI: 10.1016/j.cretres.2015.11.011 

Machimosaurus rex Fanti, Miyashita, Cantelli, Mnasri, Dridi, Contessi & Cau, 2016

Artwork by Davide Bonadonna theropoda.blogspot.com
DOI: 10.1016/j.cretres.2015.11.011

Conclusion: 

Machimosaurus rex sp. nov. is based on the articulated skeleton of a giant crocodylomorph from the Hauterivian of Tunisia. This taxon represents the first indisputable Cretaceous teleosauroid, and the first member of this clade from Africa based on well preserved remains. With a basicranial length approaching 160 cm (and a partial skeleton indicating a total body length around 10 m), M. rex is the largest known thalattosuchian. Both paleoecological data and morphological features suggest that this species was an ambush generalist predator with an ecology comparable to extant semi-aquatic crocodilians. The discovery of M. rex falsifies a global mass extinction event at the J-K transition (i.e., teleosauroid extinction), thereby highlighting the problem of sampling bias in the reconstruction of large-scale patterns in the geological record. The new Tunisian teleosaurid points to a conservative interpretation of faunal turnovers during the J-K transition: local extinction events triggered by regional ecological factors and survival of widely-distributed and eurytypic forms by means of habitat tracking.

Federico Fanti, Tetsuto Miyashita, Luigi Cantelli, Fawsi Mnasri, Jihed Dridi, Michela Contessi and Andrea Cau. 2016. The Largest Thalattosuchian (Crocodylomorpha) supports Teleosaurid Survival Across the Jurassic-Cretaceous Boundary. Cretaceous Research. In Press. DOI: 10.1016/j.cretres.2015.11.011 

http://theropoda.blogspot.com/2016/01/il-re-dei-sauri-battaglieri-morfologia.html

[PaleoEcology / Paleontology • 2014] Integrating Palaeoecology and Morphology in Theropod Diversity Estimation: A Case from the Aptian-Albian of Tunisia

Highlights

• Theropod diversity in the mid-Cretaceous of northern Africa is discussed.

• Detailed morphological, phylogenetic, and stratigraphic data are combined.

• Saharan theropod include Spinosauridae, Abelisauroidea, and Carcharodontosauridae.

• Environment-related partitioning of specific group of taxa are discussed.

Abstract

Current knowledge of theropod dinosaurs of northern Africa and their diversity during the Early Cretaceous is deceptively fragmentary and commonly associated with inadequate stratigraphic and palaeoecological data. Thereby, confused taxonomic affinities of theropod remains, represented primarily by isolated teeth and fragmentary skeletal remains, resulted in speculations on the number of genera and their stratigraphic, geographic and ecological distribution. In this study, we introduce a discussion on the theropod diversity in the Aptian–Albian of southern Tunisia based on a multidisciplinary approach that combines detailed sedimentological analyses with canonical morphological and phylogenetic analyses. This study indicates the presence of three theropod clades, Spinosauridae, Abelisauroidea, and Carcharodontosauridae. Relevant for the identification of isolated specimens from the Saharan regions, carcharodontosaurids are not represented in the Aptian-Albian teeth record and thus relatively less abundant than spinosaurids and abelisauroids. Five ziphodont tooth morphotypes are referred to ontogenetic and/or positional differences among a single abelisauroid taxon. The other three teeth morphotypes most likely represent two distinct spinosaurid taxa. Finally, the calibrated stratigraphic distribution of discussed elements indicates a clear ecological partition between theropod taxa. In particular, abelisauroids and carcharodontosaurids are commonly found in inland, fluvial deposits together with titanosauriform and rebbachisaurid sauropods, and rare crocodilians. Conversely, spinosaurids are limited to estuarine to coastal deposits dominated by a rich and diverse crocodilian fauna along with actinopterygians and sarcopterygians, including large-sized coelacanthiforms.

Keywords: Aptian-Albian; Morphology; Palaeoecology; theropod diversity; Tunisia

Fanti F., Cau A., Martinelli A., Contessi M. 2014. Integrating Palaeoecology and Morphology in Theropod Diversity Estimation: A Case from the Aptian-Albian of Tunisia. Palaeogeography, Palaeoclimatology, Palaeoecology doi: dx.doi.org/10.1016/j.palaeo.2014.05.033

Dinosauri, la convivenza pacifica (Dinosaurs, peaceful coexistence)

nationalgeographic.it/scienza/2014/06/08/foto/dinosauri_tunisia_teropodi-2174414 via @NatGeoItalia
http://theropoda.blogspot.com/2014/06/i-theropodi-dal-cretacico-inferiore.html

[Paleontology • 2013] Tataouinea hannibalis • A new sauropod dinosaur from the Early Cretaceous of Tunisia with an extreme avian-like pneumatization

Tataouinea hannibalis

Fanti, Cau, Hassine & Contessi 2013

Art by D. Bonadonna

Recent interpretations of the postcranial anatomy of sauropod dinosaurs differ about pneumatic features supporting an avian-like ventilatory system; the most conservative workers reject most postcranial pneumatizations as being unambiguous evidence of abdominal air sacs. Here we describe the first articulated dinosaur skeleton from Tunisia and refer it to a new rebbachisaurid sauropod, Tataouinea hannibalis gen. et sp. nov. The Tunisian specimen shows a complex pattern of caudosacral and pelvic pneumatization—including the first report of an ischial pneumatic foramen among Dinosauria—strongly supporting the presence of abdominal air sacs. Character optimization among Rebbachisauridae indicates that in the caudal vertebrae, pneumatization of the neural arches preceded that of the centra; in the pelvis, pneumatization of the bones adjacent to the sacrum preceded that of more distal elements. Tataouinea was more closely related to European nigersaurines than to otherwise Gondwanan rebbachisaurids; this supports an Afro-European route for rebbachisaurid dispersal.

Subject terms: Biological sciences, Evolution, Palaeontology

Fanti F., Cau A., Hassine M., Contessi M. 2013. A new sauropod dinosaur from the Early Cretaceous of Tunisia with an extreme avian-like pneumatization. Nature Communications. 4 (2080): 1–7. DOI: 10.1038/ncomms3080

http://theropoda.blogspot.it/2013/07/tataouinea-hannibalis-fanti-cau-hassine.html