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Cathrin Pfaff - One of the best experts on this subject based on the ideXlab platform.
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Tooth sections of an orthodont (Carcharhinus leucas), pseudoosteodont (†Hemipristis serra) and osteodont shark (Isurus oxyrinchus).
2018Co-Authors: Patrick L. Jambura, Cathrin Pfaff, Charlie J. Underwood, David J. Ward, Jürgen KriwetAbstract:The white line indicates the plane of the section. (A), (B), (C) Carcharhinus leucas (EMRG-Chond-T-15) has a hollow pulp cavity surrounded by tightly packed orthodentine; (D, E, F) fully mineralized tooth of †Hemipristis serra (EMRG-Chond-T-11) with a thick layer of orthodentine, surrounding the osteodentine core; (G, H, I) the crown of Isurus oxyrinchus (EMRG-Chond-T-14) is fully filled by osteodentine. Orthodentine is absent in this species. en, enameloid; mc, Meckel’s cartilage; or, orthodentine; os, osteodentine; pc, pulp cavity; pq, Palatoquadrate.
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Terminology used to describe the position of teeth within the jaw and tooth files.
2018Co-Authors: Patrick L. Jambura, Cathrin Pfaff, Charlie J. Underwood, David J. Ward, Jürgen KriwetAbstract:(A) Jaw of Hemipristis elongata in anterior view, (B) anterior part of the lower jaw of Hemipristis elongata, (C) Tooth series LPC6 of Hemipristis elongata. F, functional tooth; LMC, left Meckel’s cartilage; LPC, left Palatoquadrate cartilage; MC, Meckel’s cartilage (lower jaw); PQ, Palatoquadrate cartilage (upper jaw); R, replacement tooth; RMC, right Meckel’s cartilage, RPC, right Palatoquadrate cartilage.
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Micro-CT images of tooth series of the sphyrnid shark Sphyrna zygaena.
2018Co-Authors: Patrick L. Jambura, Cathrin Pfaff, Charlie J. Underwood, David J. Ward, Jürgen KriwetAbstract:Tooth files showing the number of teeth, tooth stages and mineralization. (A) LMC3 (lower jaw), (B) LPC3 (upper jaw) of Sphyrna zygaena (EMRG-Chond-J-8). Scalebar = 0.5cm. en, enameloid; mc, Meckel’s cartilage; or, orthodentine; pc, pulp cavity; pq, Palatoquadrate.
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Micro-CT images of tooth series of Hemipristis elongata.
2018Co-Authors: Patrick L. Jambura, Cathrin Pfaff, Charlie J. Underwood, David J. Ward, Jürgen KriwetAbstract:Tooth files showing the number of teeth, tooth stages and mineralization in (A), (B) LMC3 (lower jaw), (C), (D) LPC6 (upper jaw) of Hemipristis elongata EMRG-Chond-J-1. Scalebar = 0.5cm. en, enameloid; mc, Meckel’s cartilage; or, orthodentine; os, osteodentine; pc, pulp cavity; pq, Palatoquadrate.
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Micro-CT images of tooth sections of different developmental stages in †Hemipristis serra in frontal, sagittal and axial view.
2018Co-Authors: Patrick L. Jambura, Cathrin Pfaff, Charlie J. Underwood, David J. Ward, Jürgen KriwetAbstract:(A), (B), (C) EMRG-Chond-T-9, Pulp cavity hollow with little intrusion of osteodentine; (D), (E), (F) EMRG-Chond-T-12, Pulp cavity hollow, half filled with osteodentine; (G), (H), (I) EMRG-Chond-T-10, pulp cavity filled, tooth fully mineralized; scalebar = 1cm; en, enameloid; mc, Meckel’s cartilage; or, orthodentine; os, osteodentine; pc, pulp cavity; pq, Palatoquadrate.
Moya Meredith Smith - One of the best experts on this subject based on the ideXlab platform.
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Questioning hagfish affinities of the enigmatic Devonian vertebrate Palaeospondylus
Royal Society Open Science, 2017Co-Authors: Moya Meredith Smith, Kate Trinajstic, Sophie Sanchez, Timothy Senden, Cathrin PfaffAbstract:Palaeospondylus gunni Traquair, 1890 is an enigmatic Devonian vertebrate whose taxonomic affinities have been debated since it was first described. Most recently, Palaeospondylus has been identified as a stem-group hagfish (Myxinoidea). However, one character questioning this assignment is the presence of three semicircular canals in the otic region of the cartilaginous skull, a feature of jawed vertebrates. Additionally, new tomographic data reveal that the following characters of crown-group gnathostomes (chondrichthyans + osteichthyans) are present in Palaeospondylus : a longer telencephalic region of the braincase, separation of otic and occipital regions by the otico-occipital fissure, and vertebral centra. As well, a precerebral fontanelle and postorbital articulation of the Palatoquadrate are characteristic of certain chondrichthyans. Similarities in the structure of the postorbital process to taxa such as Pucapampella , and possible presence of the ventral cranial fissure, both support a resolution of Pa. gunni as a stem chondrichthyan. The internally mineralized cartilaginous skeleton in Palaeospondylus may represent a stage in the loss of bone characteristic of the Chondrichthyes.
De Carvalho, Marcelo R. - One of the best experts on this subject based on the ideXlab platform.
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FIGURE 26 in Taxonomic review of catsharks of the Scyliorhinus haeckelii group, with the description of a new species (Chondrichthyes: Carcharhiniformes: Scyliorhinidae)
2016Co-Authors: Soares, Karla D. A., Gomes, Ulisses L., De Carvalho, Marcelo R.Abstract:FIGURE 26. Cranial, mandibular and hypobranchial muscles in Scyliorhinus haeckelii (UERJ 2233.10, female, 432 mm TL). A: ventral view; B: lateral view. Abbreviations: V, trigeminal nerve; MAM, m. adductor mandibulae; MEP, m. epaxialis; MHC, m. constrictor hyoideus; MIN, m. intermandibularis; MLH, m. levator hyomandibulae; MLN, m. levator palpebrae nictitantis; MLP, m. levator palatoquadrati; MLS, m. levator labii superioris; MRP, m. retractor palpebrae superioris. Scale bar = 1 cm
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FIGURE 5 in A new subfamily, Styracurinae, and new genus, Styracura, for Himantura schmardae (Werner, 1904) and Himantura pacifica (Beebe & Tee-Van, 1941) (Chondrichthyes: Myliobatiformes)
2016Co-Authors: De Carvalho, Marcelo R., Loboda, Thiago S., Da Silva, João Paulo C. B.Abstract:FIGURE 5. Head skeleton of Styracura schmardae (MZUSP uncat. 508 mm DW, Belize). Note small calcified (angular) elements between hyomandibulae and lower jaws, which are slightly variable between both sides; asterisk denotes terminal portion of hyomandibula. Abbreviations: ac, angular cartilage; aoc, antorbital cartilage; fpf, frontoparietal fontenelle; hyo, hyomandibula; Mc, Meckel's cartilage; na, nasal aperture; pcf, precerebral fontenelle; pq, Palatoquadrate; prp, preorbital process; psc, prespiracular cartilage
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FIGURE 13 in Potamotrygon rex, a new species of Neotropical freshwater stingray (Chondrichthyes: Potamotrygonidae) from the middle and upper rio Tocantins, Brazil, closely allied to Potamotrygon henlei (Castelnau, 1855)
2016Co-Authors: De Carvalho, Marcelo R.Abstract:FIGURE 13. Skeletal features of Potamotrygon rex, sp. nov., from radiographs, in dorsoventral view. A) Head region of MZUSP 120354; B) Head region of MZUSP 120353; C) Close-up of specimen in A; D) Base of tail region, showing distribution and development of dermal denticles and thorns (paratype, MZUSP 120369). Abbreviations: aac, anterior angular cartilage; ao, antorbital cartilage; apr, anterior segment of propterygium; fpf, frontoparietal fontanelle; hyo, hyomandibula; Mc, Meckel's cartilage; no, nasal opening (nasal aperture); pac, posterior angular cartilage; pop, postorbital process; pq, Palatoquadrate; pro, propterygium; prp, preorbital process; psc, prespiracular cartilage; sp, supraorbital process
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FIGURE 12 in Potamotrygon limai, sp. nov., a new species of freshwater stingray from the upper Madeira River system, Amazon basin (Chondrichthyes: Potamotrygonidae)
2014Co-Authors: Fontenelle, João Pedro, Da Silva, João Paulo C. B., De Carvalho, Marcelo R.Abstract:FIGURE 12. Ventral (A), frontal (B) and detailed ventral (C) views of hyomandibular arch of Potamotrygon limai, sp. nov. (MZUSP 104033, adult male, 359 mm DW). Abbreviations: AAC: anterior angular cartilage; HYO: hyomandibula; LAC: lateral angular cartilage; MC: Meckel's cartilage; PAC: posterior angular cartilage; PQ: Palatoquadrate; PTP: posterior triangular projection; VLP: ventrolateral process. Scale bar = 20 mm.
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FIGURE 17. X in Potamotrygon limai, sp. nov., a new species of freshwater stingray from the upper Madeira River system, Amazon basin (Chondrichthyes: Potamotrygonidae)
2014Co-Authors: Fontenelle, João Pedro, Da Silva, João Paulo C. B., De Carvalho, Marcelo R.Abstract:FIGURE 17. X-ray radiographs of Potamotrygon limai, sp. nov. (A) Entire skeleton (MZUSP 104068, juvenile male, 219 mm DW; scale bar = 40 mm); (B) Detail of jaw region (MZUSP 103031, adult male, 498 mm DW; scale bar = 35 mm); (C) Detail of angular cartilages (MZUSP 103031, adult male, 498 mm DW; scale bar = 25 mm); (D) Detail of pectoral girdle (MZUSP 103031, adult male, 498 mm DW; scale bar = 25 mm); (E) Detail of pelvic girdle (MZUSP 103031, adult male, 498 mm DW; scale bar = 25 mm). Abbreviations: AAC: Anterior angular cartilage; B1: Basal segment 1; B2: Basal segment 2: BP: Basipterigium; COB: Coracoid bar; HYO: Hyomandibular cartilage; LAC: Lateral angular cartilage; MC: Meckel's Cartilage; MES: Mesopterigium; MET: Metapterigium; MSC: Mesocondyle; MTC: Metacondyle; PAC: Posterior angular cartilage; PC: Procondyle; PIB: Puboisquiadic bar; PRO: Propterigium; PQ: Palatoquadrate cartilage
Kaya Uğur - One of the best experts on this subject based on the ideXlab platform.
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Chondrocranial differences in Bufotes variabilis (Anura: Bufonidae): geometric morphometric comparison with two anuran species
2017Co-Authors: Yıldırım Elif, Kaya UğurAbstract:Few studies have focused on a detailed morphological description of the chondrocranium of bufonids. This study examines Bufotes variabilis , which is one of the widespread clades of neobatrachian anurans. We used geometric morphometrics to analyze variations of the chondrocranial shape in B. variabilis and a comparison was made with Rana macrocnemis and Hyla orientalis . Results indicated that B. variabilis is clearly different from the other species based on the presence of a bigger otic process, a more anterior position of the muscular process of the Palatoquadrate, and a narrower articular process of the Palatoquadrate. H. orientalis and R. macrocnemis are similar to each other by a wider articular process of the Palatoquadrate, a more posterior position of the muscular process of the Palatoquadrate, and a smaller and anterolateral position of the otic capsule
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Chondrocranial differences in Bufotes variabilis (Anura: Bufonidae): geometric morphometric comparison with two anuran species
'The Scientific and Technological Research Council of Turkey', 2017Co-Authors: Yıldırım Elif, Kaya UğurAbstract:WOS: 000460682100001Few studies have focused on a detailed morphological description of the chondrocranium of bufonids. This study examines Bufotes variabilis, which is one of the widespread clades of neobatrachian anurans. We used geometric morphometrics to analyze variations of the chondrocranial shape in B. variabilis and a comparison was made with Rana macrocnemis and Hyla orientalis. Results indicated that B. variabilis is clearly different from the other species based on the presence of a bigger otic process, a more anterior position of the muscular process of the Palatoquadrate, and a narrower articular process of the Palatoquadrate. H. orientalis and R. macrocnemis are similar to each other by a wider articular process of the Palatoquadrate, a more posterior position of the muscular process of the Palatoquadrate, and a smaller and anterolateral position of the otic capsule.Ege University (BAP)Ege University [2011-FEN-009]The study was a part of the first author's PhD thesis. This study was supported by Ege University (BAP, Project No. 2011-FEN-009)
Marcelo Rodrigues De ,carvalho - One of the best experts on this subject based on the ideXlab platform.
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FIGURE46 in Taxonomic and morphological revision of butterfly rays of the Gymnura micrura (Bloch & Schneider 1801) species complex, with the description of two new species (Myliobatiformes: Gymnuridae)
2017Co-Authors: Marcelo Rodrigues De ,carvalhoAbstract:FIGURE46.Radiograph of head region(dorsoventral view) showingthe arching of propterygiumand shape of the innerspace between propterygia (black line). A) Gymnura micrura (USNM 222622, 323 mm DW); B) Gymnura lessae, sp. nov. (CSIRO H7511.01, 363 mm DW); C) Gymnura sereti, sp. nov. (holotype, USNM 193741, 383 mm DW). Abbreviations: anto, antorbital cartilage; f, fontanelle; mc, Meckel's cartilage; mes, mesopterygium; nc, nasal capsule; pq, Palatoquadrate; pro, propterygium; rad, radials; scp, scapulocoracoid; S, synarcual
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FIGURE 38 in Taxonomic and morphological revision of butterfly rays of the Gymnura micrura (Bloch & Schneider 1801) species complex, with the description of two new species (Myliobatiformes: Gymnuridae)
2017Co-Authors: Marcelo Rodrigues De ,carvalhoAbstract:FIGURE 38. Mandibular arches, radiograph, dorsoventral view. A) Gymnura micrura (USNM 222622, 323 mm DW); B) Gymnuralessae, sp. nov. (USNM 25452, 390 mm DW) C) Gymnura sereti, sp. nov. (holotype, USNM 193741, 383 mm DW). Abbreviations: ap, anterior process; hyo, hyomandibula; mc, Meckel's cartilage; pq, Palatoquadrate; tb, tooth band. Black arrows indicate the most convex dorsal portion of the Palatoquadrate; white arrow indicates the furrow at the ventral border of Palatoquadrate of G.lessae