86,603 research outputs found
Rieppelophis Scanferla & Smith & Schaal 2016, GEN. NOV.
No full textGENUS RIEPPELOPHIS GEN. NOV. Etymology In honour of Olivier Rieppel, who contributed extensively to our understanding of the evolution of snakes.Published as part of Scanferla, Agustín, Smith, Krister T. & Schaal, Stephan F. K., 2016, Revision of the cranial anatomy and phylogenetic relationships of the Eocene minute boas Messelophis variatus and Messelophis ermannorum (Serpentes, Booidea), pp. 182-206 in Zoological Journal of the Linnean Society 176 (1) on page 203, DOI: 10.1111/zoj.12300, http://zenodo.org/record/545878
Rieppelophis Scanferla & Smith & Schaal 2016
No full textRIEPPELOPHIS ERMANNORUM (SCHAAL & BASZIO, 2004) COMB. NOV. Holotype SMF ME 1812, five trunk vertebrae. Locality and horizon Middle Messel Formation, Messel Pit near Darmstadt (Germany), middle Eocene (MP 11). Diagnosis A very small booid snake that can be distinguished from all other members of Serpentes by the following combination of characters: edentulous premaxilla with ascending process; nasal articulates with the medial frontal pillar; lacrimal duct opens ventrally; large fingerlike medial foot process; postorbital applied to parietal and frontal; parietal with parietal table and a pointed posterior process in sagittal crest; maxilla with two maxillary foramina, and 22 tooth positions and teeth diminishing in size posteriorly; ectopterygoid with forked maxillary process; contact with the pterygoid via a concave surface in the lateral surface of the pterygoid; parietal table present; supraorbital process of parietal well developed; supratemporal short with a conspicuous lip in its contact region with the quadrate; ∼ 183 precloacal and ∼ 36 cloacal–postcloacal vertebrae; neural spine of precloacal vertebrae robust, occupying almost half the length of the neural arch; paracotylar foramina absent; prezygapophyseal process very weakly developed; haemal keel well developed; and paired haemapophyses in postcloacal vertebrae absent and replaced by barely defined paired protuberances located below of the condyle.Published as part of Scanferla, Agustín, Smith, Krister T. & Schaal, Stephan F. K., 2016, Revision of the cranial anatomy and phylogenetic relationships of the Eocene minute boas Messelophis variatus and Messelophis ermannorum (Serpentes, Booidea), pp. 182-206 in Zoological Journal of the Linnean Society 176 (1) on page 203, DOI: 10.1111/zoj.12300, http://zenodo.org/record/545878
Lizards and snakes Warmth-loving sunbathers
No full textThis chapter includes the most recent advances about the study of lizards and snakes recovered in the Messel Pit (Middle Eocene), Germany.Fil: Smith, Krister T.. Senckenberg Research Institute and Natural History Museum Frankfurt. Department of Messel Research and Mammalogy. Section Palaeoherpetology; AlemaniaFil: Cernansky, Andrej. Comenius University in Bratislava. Department of Ecology; EslovaquiaFil: Scanferla, Carlos Agustín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Bio y Geociencias del Noroeste Argentino. Universidad Nacional de Salta. Facultad de Ciencias Naturales. Instituto de Bio y Geociencias del Noroeste Argentino; ArgentinaFil: Schaal, Stephan F. K.. Senckenberg Research Institute and Natural History Museum Frankfurt. Department of Messel Research and Mammalogy; Alemani
Figure 1 in The skull of the Upper Cretaceous snake Dinilysia patagonica Smith-Woodward, 1901, and its phylogenetic position revisited
No full textFigure 1. Holotype of Dinilysia patagonica (MLP 26–410). Skull in dorsal (A), ventral (B), right lateral (C), and posterior (D) views; fragmentary right dentary in lingual (E) and medial (F) views; right compound bone in dorsal view (G) and left compound bone in dorsolateral view (H).Published as part of Zaher, Hussam & Scanferla, Carlos Agustín, 2012, The skull of the Upper Cretaceous snake Dinilysia patagonica Smith-Woodward, 1901, and its phylogenetic position revisited, pp. 194-238 in Zoological Journal of the Linnean Society 164 (1) on page 196, DOI: 10.1111/j.1096-3642.2011.00755.x, http://zenodo.org/record/540555
Bacterial melanin production by heterologous expression of 4 hydroxyphenylpyruvate dioxygenase from Pseudomonas aeruginosa
No full textPyomelanin is a reddish-brown pigment produced by bacteria of different genera and plays a variety of physiological roles. Proposals have been regarding the use of pyomelanin in various environmental, industrial and, more recently, cosmetic applications. In Pseudomonas aeruginosa, the enzyme 4‐hydroxyphenylpiruvate dioxygenase (Hpd) converts 4-hydroxyphenylpiruvate into homogentisic acid, which represents the key intermediate for melanin biosynthesis. This work aimed to obtain Escherichia coli cells overexpressing hpd gene from the PAO1 strain to produce large amounts of pyomelanin for biotechnological purposes. The recombinant dioxygenase expression gave E. coli JM109 the ability to produce pyomelanin. A series of biotransformations led us to choose the best experimental conditions for pyomelanin production. Cells were grown at the mid-exponential phase in a mineral medium with added glucose 10 mM as carbon and energy sources and casamino acid 0.2% w/v as an amino acid source. The administration of tyrosine 1 mM after 30 min of exposure to arabinose 1% w/v made it possible to purify 213 mg/L of pyomelanin after 6 days of biotransformation. In addition to the interesting biotechnological outcomes, the resulting expression system supports the correlation between the hpd gene from P. aeruginosa PAO1 and pyomelanin synthesis
Rageryx schmidi Smith & Scanferla 2021, n. gen., n. sp.
No full textRageryx schmidi n. gen., n. sp. (Figs 1; 2 A-C; 3A-E; 4A-D; 5A-C; 6A-C; 7A, B; 8A-D; 9A-D; 10A-D; 11B-E; Appendix 1: Figs S1-S 8) urn:lsid:zoobank.org:act: AEB68284-BF3F-4980-8CD3-960415C732E0 HOLOTYPE AND ONLY KNOWN SPECIMEN. — HLMD-Me 9723, nearly complete skeleton. TYPE LOCALITY. — Early or middle Eocene (MP 11, Ypresian or Lutetian) of the Middle Messel Formation, Germany. Known only from type locality. ETYMOLOGY. — After Dietmar Schmid, past president of the Senckenberg Gesellschaft für Naturforschung, in recognition of his estimable service to the society. DIAGNOSIS. — Small boid snake with the following unique combination of characters: skull with short snout and moderately extensive braincase; orbits located in front of longitudinal midpoint of skull; anterior margin of premaxilla in line with arch defined by maxillae; nasal process of premaxilla small but distinct, with flat anterior face; maxillary tooth count around 16; maxilla with small posteromedial flange for ectopterygoid; prefrontal with anterolateral lamina and medial and lateral footprocesses; frontal table trapezoidal; parietal with low mid-sagittal ridge on posterior third; parasphenoid rostrum triangular with very broad base and weak, posterior ventral midline ridge; right Vidian canal larger than left; shelf bounding groove for posterior opening of Vidian canal obscures foramen for palatine branch of cranial nerve VII; supraoccipital significantly exposed externally; free end of supratemporal short; quadrate ramus of pterygoid with longitudinal, dorsally open groove; palatine ramus of pterygoid long; ectopterygoid straight with simple anterior end; coronoid present but reduced, lacking a distinct anteromedial process; compound bone with gradual decay of coronoid eminence anteriorly, and low, straight prearticular crest; about 220 precloacal and 38 caudal vertebrae; mid-trunk vertebrae with low and short neural spine; posterior trunk vertebrae without depressed neural arch; caudal neural spines relatively thick but not bifurcated; neural arch in middle of tail vaulted with flat, vertical posterior surface; distal caudal vertebrae short and tall (much taller than long); supernumerary process of caudal vertebrae present at least in rudimentary form, viz., pterapophyses present on majority of caudals, small postzygapophyseal wings and posterior extensions of the prezygapophysis present; and zygosphene-zygantral articulations present on distal caudal vertebrae. REMARKS Three erycine taxa have been named from the Eocene of Europe, Calamagras gallicus Rage, 1977, Cadurceryx filholi Hoffstetter & Rage, 1972 and Cadurceryx pearchi Holman, Harrison & Ward, 2006. The first is known from much of the Ypresian (early Eocene), from MP 8+9 to MP 10 (Rage 1977, 2012). The second is known possibly as early as MP 13 and certainly from MP 16 to MP 19+20 (Hoffstetter & Rage 1972; Rage 1984, 2012, 2013). The third is described only from the late Eocene Headon Hill Formation of England. The Middle Messel Formation, considered to be MP 11 (Franzen 2005), falls in-between and straddles the Ypresian-Lutetian boundary (Lenz et al. 2015). Smith (2013) found that Calamagras weigeli from the late Eocene of North America is closely related to Ungaliophiinae, a result confirmed here. He also found that the type species of Calamagras Cope, 1873, Cal. murivorus Cope, 1873 from the early Oligocene, shows similarity of proportions to Cal. weigeli, and even if a lack of referred material with diagnostic characters (absence of hemapophyses on all caudal vertebrae; see Smith 2013) currently prevents a critical appraisal of its relationships, it is not unlikely that Cal. murivorus will also turn out to be related to Ungaliophiinae. Thus, the genus name Calamagras cannot be used for HLMD-Me 9723. Cadurceryx filholi, in contrast, is a highly derived species in which the accessory processes are not only more highly developed but also extend far into the trunk. This unusual morphology is not seen in any living erycine. Furthermore, Cad. filholi shows a very depressed neural arch on posterior trunk vertebrae, a derived character that it shares with extant Eryx (and also Charininae) and that distinguishes it from the vaulted neural arch of HLMD- Me 9723. Whatever its precise phylogenetic relations, Cad. filholi is clearly not closely related to HLMD-Me 9723, and the name Cadurceryx cannot be applied to the specimen. Cadurceryx pearchi, finally, is known exclusively from caudal vertebrae (Holman et al. 2006). The two diagnostic features of Cad. pearchi with respect to Cad. filholi, according to the authors, were the size of the cotyle (larger than neural canal) and the presence of a ‘tubercle’ on the anterior end of the prezygapophysis. The tubercle was not labelled, but if we understand it correctly, it is absent in Rageryx schmidi n. gen., n. sp. The size of the cotyle with respect to the neural canal appears to be variable in the type series of Cad. pearchi (Holman et al. 2006: figs. 2a, d and 3a, e), potentially as a result of vertebral position or intraspecific variation, calling into question the validity of this diagnostic feature. There are additional differences between Cad. pearchi and R. schmidi n. gen., n.sp, such as caudal vertebrae being taller than wide and having a more vaulted neural arch. Thus, there is no reason to consider that these two species are closely related. The question now arises whether Rageryx n. gen. is the appropriate generic name for “ Calamagras ” gallicus. Rage (1977) stated that small pterapophyses are present in the holotype caudal vertebra, MNHN GR 7896, but other accessory processes are absent. It is remarkable, therefore, to find more of them present in Rageryx schmidi n. gen., n. sp., a younger European taxon. However, as noted in the description, it is the pterapophyses that occur most proximally in HLMD-Me 9723. Therefore, MNHN GR 7896 might derive from a more proximal part of the tail where the other processes do not occur. On the other hand, its proportions speak for a more distal position in the caudal series. MNHN GR 7896 also appears to have more bulbous processes than HLMD-Me 9723. With regard to the shape of the neural spine, HLMD-Me 9723 and referred trunk vertebrae of “ Cal. ” gallicus appear to be fully comparable. A clear resolution of this taxonomic problem will have to await the discovery and description of further caudal material from the Ypresian of France, preferably from the type locality, i.e., Grauves in the Paris Basin. Given the distinctiveness and relatively early occurrence of Cadurceryx in Europe (Rage 2012), one hypothesis is to derive it from “ Calamagras ” gallicus or Rageryx schmidi n. gen., n. sp. (or a closely related form). A second hypothesis is that it represents an early dispersal of a taxon more closely related to Eryx into Europe. Cranial remains of these fossils apart from Messel are meager, and there are no fossils, at present, from MP 12 (Rage 2012). Consequently the data are insufficient to determine the relationships of Cad. filholi. DESCRIPTION HLMD-Me 9723 is a nearly complete skeleton, highly contorted and missing four sections of the axial skeleton (Fig. 1A). It is preserved on three plates that had been broken during excavation and rejoined. Because of the missing sections, the total length of the animal can only be given as c. 52 cm. A counterpart is not present in the HLMD collections. The orbits are located in front of the longitudinal midpoint of the skull (Fig. 1B; Appendix 1: Fig. S1). The skull on the whole shows a short snout and moderately extensive braincase. Thus the general proportions of the skull are similar to ungaliophiine boids, especially Ungaliophis Müller, 1880, and to Tropidophis Bibron in Ramon de la Sagra, 1840 (Cundall & Irish 2008: fig. 2.62 and 2.65). They differ both from the primitive alethinophidian pattern, in which the elongate braincase is narrow anteriorly but widened at the otic capsule, and from most erycines, in which the braincase behind the orbit is shortened (Cundall & Irish 2008). Like those of several adult boid skulls examined, the posterior region of the parietal bone of HLMD-Me 9723 is clearly projected posteriorly, especially the supratemporal processes. This posterior projection overlaps the anterodorsal edge of the supraoccipital, like in adult individuals of large and small boids and macrostomatans in general (e.g., Smith & Scanferla 2016). Also, the well-preserved tips of the neural spines of the trunk vertebrae show well-finished caps of bone.Taken together, these anatomical traits present in the parietal bone, and the advanced state of ossification observed in skull and trunk vertebrae, evidence that HLMD-Me 9723 represents an adult postnatal ontogenetic stage. Thus, the species it represents was apparently smaller than typical adult Rosy Boas (Lichanura trivirgata, length 43-112 cm), and many adult Rubber Boas (Charina bottae, length 35-84 cm) (Stebbins 2003). HLMD-Me 9723 is also smaller than many Eryx. Er. johnii and Er. tataricus are the largest of the genus, with total length in large individuals> 1 m, but all other species are smaller (Seufer 2001). Premaxilla The premaxilla is only partially preserved, yet there is every indication that its anterior margin was in line with the curvature of the arch defined by the maxillae (Fig. 1B, C). Thus, it was not produced far forward, unlike in extant erycines, Loxocemus bicolor Cope, 1861 and Calabaria reinhardtii. A small, ovate nasal process is present that projects posterodorsally and has a flat anterior surface that would have been visible externally between the nasal bones. It is similar to that of many boids and totally unlike the low crest completely hidden between the nasal bones in Eryx (Cundall & Irish 2008). Maxilla (Fig. 2; Appendix 1: Fig. S2) The maxilla is elongate, slightly dorsally arched element (Fig. 2 A-C). Its anterior end is most notable for a large dorsal foramen (superior alveolar foramen, s.a.f.) continued anteriorly by a deep groove. This foramen is most comparable to that in Charina bottae, which, however, is disposed more laterally. It presumably transmits the subnarial artery and superior alveolar nerve onto the snout, but the reasons for its large dimensions are unknown. A weak ascending process begins to rise adjacent to the groove and terminates at the level of the superior alveolar foramen and palatine process (pl.pr.); it is more strongly developed than in Lichanura trivirgata (Fig. 2H, I), but not as strong as in Ch. bottae. The lateral surface of the bone is pierced by a single, elongate labial foramen (l.f.), which transmits branches of the maxillary artery and superior alveolar nerve. A small facet, probably for the prefrontal, is present medial to the ascending process. The dorsal surface of the posterior end of the maxilla appears to show several fine, longitudinal striae (Fig. 2A), whose origin may lie with the ectopterygoid articulation. The palatine process is poorly preserved, and little can be said of its size, orientation, and morphology; however, it appears to have been asymmetrical, with a steep posterior margin and a probably more gradual anterior margin. Presumably the palatine process was pierced by a foramen, as in other boids. A single foramen is visible on the dorsal surface at the level of the posterior margin of the palatine process, as in other boids (Fig. 2D, G). Nasals (Fig. 3; Appendix 1: Fig. S3) The elongate nasals are gently dorsally convex in sagittal and transverse planes (Fig. 3 C-E). They contact one another on the midline for most of their length. Each comprises a plate posteriorly over the nasal capsule (the horizontal lamina) and a long, slightly thickened anteromedial process (Fig. 3A, B). All examined Eryx also have a strong horizontal expansion of the anterior end of the horizontal lamina (Fig. 3 F-H), which is lacking in Lichanura trivirgata (Fig. 3 K-N) and other boids. The anteromedial processes curve ventrally to contact the nasal process of the premaxilla, which slightly separates them at their distal end. An anterolateral process, as in Boa Linnaeus, 1758, is lacking. Posterolaterally the nasal is overlapped by the prefrontal, as in Li. trivirgata and Charina bottae but unlike in Eryx (Rieppel 1978a; Cundall & Irish 2008). The posterolateral end of the nasal is squared off, but posteromedially there appears to be a posterior expansion; due to the tightly apposition of the frontal in this region, the true morphology is uncertain. A triangular, posteromedial prong extending posteriorly between the frontals was present in all examined Eryx but is lacking in Li. trivirgata and Ch. bottae. (In Boa and Candoia carinata, the nasals taper posteriorly and so they necessarily form a triangular point, but there is no anteromedian notch in the frontal; rather the space is occupied by the prefrontal. Thus, such a prong can be regarded as absent in these taxa.) There is no evidence of a vertical buttress that would have articulated with the lateral (subolfactory process) or medial pillars of the frontal at the prokinetic joint, unlike in extant erycines (Fig. 3I, J, N, O) as well as some other fossorial forms (Rieppel 1978a; b; pers. obs.), but it is likely that the nasal contacted the frontal beneath the olfactory tracts, as in most constrictors. All examined Eryx have one or two foramina through the posterolateral corner of the nasal, although it is uncertain what structures pass through it; these foramina are lacking in HLMD-Me 9723 and other boids. Prefrontal (Appendix 1: Fig. S4) On the whole, both elements are poorly preserved. A large anterolateral lamina is present (Fig. 1B), unlike in Eryx. The triangular dorsomedial projection of this lamina that extends medially behind the nasals toward the contralateral element is comparable in extent to Charininae; the prefrontals do not meet one another on the midline. The orbital lamina forms the anterior wall of the orbit. The medial foot-process is well developed and curves slightly laterally. The prefrontal is complete enough to deduce that the lateral foot-process was less well developed, more like Boa constrictor than the larger process of Eryx, Charininae and Calabaria reinhardtii. A small foramen of unknown significance pierces the ventral margin of the bone in the embayment between the two foot-processes. Frontal (Fig. 4; Appendix 1: Fig. S5) The smooth frontal table is trapezoidal, with a long medial, shorter and slightly concave lateral, and oblique anterior and posterior margins (Fig. 4A). Consequently there is no deep median notch between the frontals for reception of the nasals. In this it differs from the parallelgram-shaped table of Eryx (Fig. 4E). It appears that a small foramen exits dorsally through the posterolateral corner. The anterolateral margin is smooth and lacks a distinct notch for the prefrontal, unlike in Lichanura trivirgata (Fig. 4I). A prominent supraorbital shelf, as in Boinae, is absent (Fig. 4B, C). The posterolateral corner has a postolateral projection for accomodating the anterolateral corners of the parietal dorsally (Fig. 4A, D), like in Eryx (Fig. E, H) but unlike in Boinae and Li. trivirgata (Fig. I, L). A small facet for articulation of the postorbital may be present. The ventral portion of the frontals is almost certainly present but could not be distinguished due to crushing. Thus, the extent and morphology of the medial and lateral frontal pillars and the posteroventral projection bounding the optic foramen cannot be ascertained. Postorbital (Appendix 1: Fig. S6) The dorsal portion shows an elongate facet where it articulated along the parietal and, anteriorly, a small part of the frontal (Fig. 1B). It tapers strongly ventrally, so that the postorbital process is thin, unlike in Boinae and some Eryx (e.g., Er. colubrinus). The process is broken, so that its ventral extent is uncertain, but comparison of the left and right elements suggests that it was less extensive than in most booids. The preserved portion shows no evidence of a posterior deflection, as is present in Candoia carinata and many Eryx (e.g., Er. colubrinus, Er. conicus, Er. jayakari and Er. tataricus, but not Er. jaculus). Parietal The parietal bone is relatively broad, only slightly longer than wide (Fig. 1B). Its widest point is found anterior to midlength, well in front of the otic capsules. The anterior margin is shallowly concave except at the midline, where a small process projects between the frontals. The dorsal surface of the anterior part of the parietal is flat, and a low mid-sagittal ridge is developed only in about the posterior one-third of the bone. In this respect it is similar to Lichanura, Charina and Ungaliophiinae and differs from Eryx and Boinae, in which the sagittal crest is sharper and far more extensive (Cundall & Irish 2008). The ventral extent of the parietal forming the lateral wall of the braincase is almost certainly present, but could not be distinguished due to crushing. Parabasisphenoid (“sphenoid” of Cundall & Irish 2008) (Fig. 5; Appendix 1: Fig. S7) This is a triangular element with a broad, regularly tapering rostrum (Fig. 5A, B). The rostrum is broader relative to the width of the basisphenoid portion of the bone than in any examined constrictor. Its dorsal surface is weakly concave in transverse section (Fig. 5A). Its ventral surface is nearly flat proximally, but distally there is a ventral keel formed beyond the terminus of the cristae trabecularis. On the main body of the basisphenoid portion there is a weak, midline ridge, similar to that seen in some constrictors, like Loxocemus bicolor, Lichanura trivirgata, and Candoia carinata, but no indication that the ridge bifurcates anteriorly, as it does in Lo. bicolor (Smith 2013) and Li. trivirgata (Fig. 5H). In dorsal view the sella turcica – dorsal margin of the dorsum sella or pituitary fossa – is approximately in line with the greatest lateral extent of the bone, but crushing has nearly obliterated the fossa.It appears that the badly crushed parasphenoid wings are strong with a well-developed articulation for the parietal articulation, but their exact extent cannot be determined.If our interpretation is correct, these project more strongly than any observed in extant constrictors, except Candoia carinata, where they are also anteroposteriorly longer. Neurovascular foramina are difficult to distinguish in the CT scan. The right egress for cranial nerve VI, however,appears to be present at approximately the level of the lateral margin of the pituitary fossa. Assuming mirror symmetry for the left egress, the foramina would be widely spaced, like in Lichanura trivirgata (Fig. 5G) and most examined snakes but unlike in Loxocemus bicolor (Smith 2013), some Eryx [e.g., Er. johnii (Fig. 5D), Er. tataricus] and Candoia carinata. The right Vidian canal is distinctly larger than the left one, as in Boidae (Underwood 1976). Prootic (Fig. 6) The opening for the maxillary ramus of the trigeminal nerve (V2) is presumably situated between the prootic and the parietal, with the prootic deeply notched for the nerve, but the notch is not distinct on either side (Fig. 6A). The opening for the mandibular ramus (V3) is located posteriorly. In most boids (Fig. 6D, G) these foramina are separated by an ophidiosphenoid (sensuGauthier et al. 2012), but it is lacking in Eryx colubrinus, Er. jaculus, Er. muelleri, and Er. tataricus (among examined Eryx); the region is too damaged to be certain in HLMD-Me 9723. The hyomandibular branch of the facial nerve (VIIh) opens within the trigeminofacialis chamber, and well within the margins of the lateral opening of V3. Dorsally the prootic evinces an elongate groove for the reception of the supratemporal. In ventral view the prootic exhibits an ophidiosphenoid foramen anteriorly (Fig. 6C), like in many boids but unlike in Ungaliophis continentalis Müller, 1880. There is an anteromedially trending groove that would have continued into the posterior opening of the Vidian canal on the basisphenoid. At the base of the groove is a relatively large foramen for the palatine ramus of cranial nerve VII, and the dorsolateral margin of the groove is expanded as a shelf that obscures said foramen in lateral view. A groove as such has a capricious phylogenetic distribution. Lichanura trivirgata (Fig. 6I) and Charina bottae, but not Ungaliophiinae or Eryx (Fig. 6F), share with HLMD-Me 9723 the shelf that obscures the foramen for the palatine branch of the facial nerve (VIIp). The ventral edge of the prootic in HLMD-Me 9723 is wedge-shaped, fitting into the broad notch between the parabasisphenoid anteriorly and basioccipital posteriorly. In medial view two foramina, a larger anterior opening for cranial nerve V and a smaller posterior opening for cranial nerve VII, pierce the cranial vault to enter the trigeminofacialis chamber (Fig. 6B). The impression of the vestibulum and parts of the relatively large anterior and lateral semicircular canals can be seen. In contrast to Eryx, in particular (Fig. 6E), the vestibulum is relatively small. The anterior semicircular canal extends to the anterior margin of the bone and well away from the vestibulum. Supraoccipital The supraoccipital achieves significant exposure between the parietal and otoccipitals (Fig. 1B), comparable to Loxocemus bicolor, Lichanura trivirgata and Charina bottae, but unlike in Eryx (Cundall & Irish 2008). Anteriorly on the midline a small prong projects into a corresponding notch in the posterior margin of the parietal. Otooccipital ( sensu Maisano & Rieppel 2007) This paired element is poorly exposed, and segmentation was dee
Special-needs patients in pediatric dentistry: Progeroid syndrome. A case of dental management and oral rehabilitation
No full textThis report presents a case of an eight-year-old girl affected by a progeroid syndrome of unclear genetic origins. The patient’s dental history included oligodontia, premature deciduous exfoliation and roots abnormalities. She was treated with comprehensive oral rehabilitation using dentures. Oral health instructions were given during the whole treatment and follow-up period. The goal of improving the masticatory function and the esthetic was achieved, allowing the patient to increase her social abilities and self-confidence
Figure 2 in Ontogeny of the skull of the blind snake Amerotyphlops brongersmianus (Serpentes: Typhlopidae) brings new insights on snake cranial evolution
No full textFigure 2. Dorsal view of the skull of Amerotyphlops brongersmianus throughout embryonic and postnatal ontogeny: A, embryo at Stage 33; B, embryo at Stage 34; C, embryo at Stage 36; D, hatchling; E, juvenile; F, adult. Abbreviations: bo, basioccipital; fr, frontal; mx, maxilla; n, nasal; ot, otooccipital; p, parietal; pa, palatine; pbs; parabasisphenoid; pmx; premaxilla; po, prootic; pp, postorbital process; prf, prefrontal; q, quadrate; so, supraoccipital. Scale bars equal to 1 mm.Published as part of Chuliver, Mariana, Scanferla, Agustín & Koch, Claudia, 2023, Ontogeny of the skull of the blind snake Amerotyphlops brongersmianus (Serpentes: Typhlopidae) brings new insights on snake cranial evolution, pp. 698-718 in Zoological Journal of the Linnean Society 197 (3) on page 703, DOI: 10.1093/zoolinnean/zlac050, http://zenodo.org/record/769092
Variations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
A digital workflow for computer-guided implant surgery integrating CBCT, model scanning, and CAD/CAM for a complete edentulism implant-supported prosthesis: A technique procedure
No full textThe utilization of digital 3D surface images (STL format) for planning cases of computer-guided implant surgery is very useful in partially edentulous cases. In fully edentulous cases, however, the absence of teeth makes it necessary to add reference markers. The proposed protocol demonstrates a simple procedure that allows for the superimposition of STL and radiologic data (DICOM format). In the presented patient case, the tissue-bearing area of the prosthesis was relined with a polysulfide impression material and sent to the laboratory. A master cast was produced. The prosthesis was relined to improve intraoral stability and was provided with at least three radiopaque 3D markers. An STL copy of the prosthesis and the model was generated through a laboratory scanner. The patient wore the prosthesis with the attached markers during the 3D radiologic examination. In the planning software (CoDiagnostiX; Dental Wings), the prosthesis markers on the STL were matched to the corresponding markers visible on the DICOM data. Then, the STL of the model was matched to that of the prosthesis. Once the STL of the mucosa and the prosthesis were imported into the software, new possibilities arose, ie, the option to add other digital or traditional tooth setups to the same radiologic data or to design a surgical guide based on the actual mucosa of the patient
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