Fourth mandibular tooth from the left side of <i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), showing the serrations.

<p>A, labial surface; B, detail for apex carina; C, detail for middle carina; D, detail for basal carina. Scale bar in A: 10 mm; B, C and D: 1 mm.</p

<i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R) teeth measurements in mm.

<p><b>1std (d4 ?)</b>, first exposed dentary tooth of the right side; <b>1std (d4 ?) s</b>, first exposed replacement dentary tooth of the left side; <b>d</b>, dentary tooth; <b>fabl</b>, fore-after basal length; <b>lmt</b>, last exposed maxillary tooth; <b>m</b>, maxillary tooth; <b>tch</b>- tooth crown height; –, lack information; ∼, estimated measurement.</p

<i>Sahitysuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), in dorsal view.

<p>A, photo; B, illustration. <b>9–12th mlt</b>, eighth to eleven left maxillary teeth; <b>an</b>, angular; <b>anr</b>, angular ridge; <b>afo</b>, mandibular adductor fossa; <b>aof?</b>, antorbital fenestra?; <b>art</b>, articular; <b>bs</b>, basisphenoid; <b>bo</b>, basioccipital; <b>boc</b>, basioccipital middle crest; <b>bot</b>, basioccipital basal tubera; <b>chg</b>, choanal groove; <b>cq</b>, cranio-quadrate passage; <b>d</b>, dentary; <b>dhl</b>, left hypertrophied replacement tooth; <b>dhr</b>, right hypertrophied dentary tooth; <b>ec</b>, ectopterygoid; <b>expp</b>, exoccipital posterior process; <b>f</b>, frontal; <b>fä</b>, foramen aereum; <b>fcp</b>, foramen caroticum posterius; <b>fic</b>, foramen intermandibularis caudalis; <b>fme</b>, median Eustachian foramen; <b>fot</b>, upper temporal fossa; <b>fra</b>, fractured area; <b>fv</b>, foramen vagi; <b>int</b>, intercentrum; <b>j</b>, jugal; <b>jd</b>, jugal latero-ventral depression; <b>l</b>; lachrymal; <b>lptyp</b>, lateral pterygoidal process (flange); <b>ltf</b>, laterotemporal fenestra; <b>m</b>, maxilla; <b>m1l</b>, first left maxillary tooth; <b>m1r</b>, first right maxillary tooth; <b>m3l</b>, third left maxillary tooth; <b>m3r</b>, third right maxillary tooth; <b>m4l</b>, fourth left maxillary tooth; <b>m5l</b>, fifth left maxillary tooth ; <b>nc</b>, nuchal crest; <b>occ</b>, occipital condyle; <b>or</b>, orbit; <b>oti</b>, otic incisure; <b>oto</b>, otoccipital; <b>p</b>, parietal; <b>pl</b>, palatine; <b>pmt</b>, posterior maxillary teeth; <b>po</b>, postorbital; <b>pop</b>, para-occipital process; <b>pfr</b>, prefrontal; <b>pro</b>, proatlas; <b>pty</b>, pterygoid; <b>q</b>, quadrate; <b>qd</b>, quadrate depression; <b>qdc</b>, quadrate dorsal crest; <b>qj</b>, quadratojugal; <b>rap</b>, retroarticular process; <b>san</b>, surangular; <b>sanr</b>, surangular lateral ridge; <b>sf</b>, siphoneal foramen; <b>soc</b>, supraoccipital; <b>sof</b>, suborbital fenestra; <b>spl</b>, splenial; <b>sq</b>, squamosal; <b>sqp</b>, squamosal posterior process (squamosal prong); <b>utf</b>, upper temporal fenestra; <b>XII</b>, twelfth cranial nerve exit. Scale bar: 100 mm.</p

New Information on the osteology and a taxonomic revision of The genus <i>Thalassodromeus</i> (Pterodactyloidea, Tapejaridae, Thalassodrominae)

<p><i>Thalassodromeus sethi</i> (Pterodactyloidea, Tapejaridae, Thalassodrominae) is a unique pterosaur from the Romualdo Formation, Araripe Basin (Early Cretaceous, Albian). A large sagittal cranial crest (the largest known ossified crest of any pterosaur) and unusual toothless bladed jaws constitute some of its outstanding anatomical features. Its holotype (DGM 1476-R, almost complete skull and mandible in three dimensions) represents one of the largest pterosaur skulls ever found. Here, we provide a detailed osteological redescription of the holotype, which has only been preliminarily described. We also describe and depict for the first time some skeletal regions of <i>Th. sethi</i>, including the occiput, the palatal openings, and a dentary fragment. Finally, in the light of new information concerning this species, we revisited the specimen NMSG SAO 251093 (an incomplete mandible), also from the Romualdo Formation and originally referred to <i>Th. sethi</i> but recently redescribed as a new species of dsungaripterid pterosaur named <i>Banguela oberlii</i>. Here, the analysis of a cast (MN 4703-V) and its inclusion in a phylogenetic analysis recovered NMSG SAO 251093 within the Thalassodrominae, as a sister taxon of <i>Th. sethi</i> and indeed different from it at the species level. We hereby rename it <i>Thalassodromeus oberlii</i>, comb. nov. These considerations provide new data for discussions concerning the morphology of the Tapejaridae, the diversity of the Araripe pterosaur fauna, and the complex evolution of the pterodactyloid palatal region, as well as data for future morphofunctional studies of <i>Thalassodromeus</i>.</p> <p>SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at <a href="http://www.tandfonline.com/UJVP" target="_blank">www.tandfonline.com/UJVP</a></p> <p>Citation for this article: Pêgas, R. V., F. R. Costa, and A. W. A. Kellner. 2018. New information on the osteology and a taxonomic revision of the genus <i>Thalassodromeus</i> (Pterodactyloidea, Tapejaridae, Thalassodrominae). Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2018.1443273.</p

Biochronology of the Crocodylomorpha based on the strict consensus tree obtained by the phylogenetic analysis (see text for details) and recorded temporal range.

<p>Biochronology of the Crocodylomorpha based on the strict consensus tree obtained by the phylogenetic analysis (see text for details) and recorded temporal range.</p

Measurements in mm of <i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), adapted from [25] ∼, estimated measurement.

<p>Measurements in mm of <i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), adapted from <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0081386#pone.0081386-Langston1" target="_blank">[25]</a> ∼, estimated measurement.</p

<i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), in left lateral view.

<p>A, photo; B, illustration. For abbreviations see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0081386#pone-0081386-g001" target="_blank">Figure 1</a>. Scale bar: 100 mm.</p

<i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R) cervical vertebrae.

<p>A, right lateral view of axis and third cervical vertebra; B, anterior view, showing the odontoid process. <b>cvt cv3</b>, centrum of third cervical vertebra; <b>di ax</b>, axis diapophysis; <b>di cv3</b>, diapophysis of third cervical vertebra; <b>lpsop cv3</b>, postspinal lamina of third cervical vertebra; <b>na ax</b>, axis neural arch; <b>na cv3</b>, neural arch of third cervical vertebra; <b>ncs</b>, neuro-central suture; <b>ns ax</b>, axis neural spine; <b>ns cv3</b>, neural spine of third cervical vertebra; <b>od</b>, odontoid process; <b>pa ax</b>, axis parapophysis; <b>pa cv3</b>, parapophysis of third cervical vertebra; <b>poz ax</b>, axis postzygapophysis; <b>poz cv3</b>, postzygapophysis of third cervical vertebra; <b>prz cv3</b>, prezygapophysis of third cervical vertebra. Scale bar: 10 mm.</p

<i>Sahitisuchus fluminensis</i> gen. et sp. nov. (MCT 1730-R), in occipital view.

<p>A, photo; B, illustration. For abbreviations see <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0081386#pone-0081386-g001" target="_blank">Figure 1</a>. Scale bar: 100 mm.</p