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FIGURE 6 in Historical and fossil evidence of an extinct endemic species of Leiocephalus (Squamata: Leiocephalidae) from the Guadeloupe Islands
No full textFIGURE 6. Pterygoid, squamosal and quadrate bones of Leiocephalus roquetus sp. nov. A: 3D Model of the right pterygoid of the holotype (MHNBx 2002.1871); B: Paratype left pterygoid bone "PGR6. square C11d. décapage 14.X" collected PGR6 deposit; C: 3D Model of the right squamosal of the holotype (MHNBx 2002.1871); D: Paratype left squamosal bone "PGR6. square B9b. décapage 22.IX" collected in PGR6 deposit; E: 3D Model of the left quadrate of the holotype (MHNBx 2002.1871); F: Paratype left quadrate bone "PGR6. square C11c. décapage 15.XI" collected in PGR6 deposit. Abbreviations: a.-d. d.: antero dorsal depression, a. e.: articular surface with the ectopterygoid bone, a. p.: articular surface with the palatine bone, a. r.: anterior ramus, c.: conch, d. p.: dorsal process, p. c.: posterior crest, p. e.: pit for the insertion of the epipterygoid, p. l.: pterygoid lamina, p. t.: pterygoid teeth?, pa. p.: palatine process, po. p.: posterior process, t. c.: tympanic crest, t. p.: transverse process, t. s.: tooth socket, v. p.: ventral process. Scale bars= 2mm.Published as part of Bochaton, Corentin, Charles, Laurent & Lenoble, Arnaud, 2021, Historical and fossil evidence of an extinct endemic species of Leiocephalus (Squamata: Leiocephalidae) from the Guadeloupe Islands, pp. 383-409 in Zootaxa 4927 (3) on page 394, DOI: 10.11646/zootaxa.4927.3.4, http://zenodo.org/record/454233
Alsophis sp. Fitzinger 1843
No full textAlsophis sp. EXAMINED MATERIAL. — 1049 bone elements corresponding to broken trunk vertebrae, cervical vertebrae, and post-cloacal vertebrae are attributed to the genus Alsophis on the basis of their size and overall morphology. REMARKS The morphology of cervical and post-cloacal vertebrae was not deeply studied in the framework of this study which precludes a specific identification. These elements were associated to Alsophis mainly on the basis that it was possible to confidently assume they belong to a colubrid snake larger than Erythrolamprus and presenting no strong difference with our modern specimens of Alsophis.Published as part of Bochaton, Corentin, Boistel, Renaud, Grouard, Sandrine, Ineich, Ivan, Tresset, Anne & Bailon, Salvador, 2019, Fossil dipsadid snakes from the Guadeloupe Islands (French West-Indies) and their interactions with past human populations, pp. 501-523 in Geodiversitas 41 (12) on page 512, DOI: 10.5252/geodiversitas2019v41a12, http://zenodo.org/record/369982
Measurement data of modern and archaeological Indotestudo tortoises
No full textThese data are measurements collected on modern and archaeological tortoises that have been used in the following publication:
Bochaton C., S. Chantasri, M. Maneechote, J. Claude, C. Griggo, W. Naksri, H. Forestier, H. Sophady, P. Auertrakulvit, J. Bowonsachoti and V. Zeitoun., 2023. Zooarchaeological investigation of the prehistoric exploitation of reptiles and amphibians in Thailand and Cambodia with a focus on the Yellow-Headed tortoise (Indotestudo elongata (Blyth, 1854)). PCI Archaeolog
Leiocephalus roquetus Bochaton & Charles & Lenoble 2021, sp. nov.
No full text<i>Leiocephalus roquetus</i> sp. nov. <p>Fig. 2, 3, 4, 5, 6, 7</p> <p> <b>Diagnosis.</b> <i>Leiocephalus roquetus</i> differs from all other congeners by the morphology of its parietal bone that bears adductor crests fused into a single crest in the posterior area of the bone in large specimens. In addition of this character, <i>L. roquetus</i> presents a unique combination of characters: absence of enlarged snout scales, and occurrence of five scales in contact with the first pair of enlarged frontal scales (pattern of type I of Pregill (1992)), the occurrence of three internasal scales, a prominent dorsal body crest, absence of keeled ventral scales, frontal bone exposed dorsally between the nasal and prefrontal bones, skull rugosities on the frontal bone, premaxillary spine constricted just above the dentigerous process, a well-developed posterior process of the septomaxilla, a distinct dorsal process of the squamosal, a well-developed angular process of the dentary, and transition from bicuspid to tricuspid teeth occurs between the height and sixth most anterior dental position of the dentary. This new taxon also presents several differences with other known Lesser Antillean <i>Leiocephalus</i> specimens (see below).</p> <p> <b>Derivatio nominis</b>: The species is named in reference to the first common name “roquet” attributed by Du Tertre (1654) and de Rochefort (1658) to the leiocephalid lizards of Guadeloupe. As pointed out by Breuil (2002), this name was latter erroneously attributed to <i>Anolis</i> lizards and, as the Amerindian name of <i>Leiocephalus</i> is unknown, we choose to retain the original name given to these squamates. The English name of this lizard would be “Curlytail roquet” and the French name “Léiocéphale roquet”.</p> <p> <b>Type locality</b>: Guadeloupe,? La Désirade Island, Lesser Antilles.</p> <p> <b>General description of the holotype.</b> The holotype is a complete, dry taxidermy specimen (labeled MHNBx 2002.1871) preserved in the Natural History Museum of Bordeaux (France). This specimen has a snout-vent length (SVL) of 10.8 cm and measures 26.5 cm in total length (Fig. 2). Microtomography reveals the skull to be fully preserved (Fig. 3). The key morphological features of the holotype are as follows: enlarged nasal bones, the narrow nasal process of the premaxilla is triangular, the dorsal part of the premaxilla is fully enclosed by the nasal bones, the premaxilla lacks lateral spines and bears 7 tooth positions, the nasal-maxillary suture is arched toward the midline of the snout, the nasal process of the frontal bone is dorsally exposed between the nasal and prefrontal bones, the pterygoid bears teeth but palatine teeth are absent, lacrimal and postfrontal bones are present, the septomaxilla bears a quadrangular lateral wing with a thin posteriorly oriented process, the frontal is narrow with dermal ornamentation, the parietal foramen is on the fronto-parietal suture, the adductor crests of the parietal table converge but do not touch and are posteriorly separated by a depressed area, the anterior part of the parietal table presents a dermal ornamentation, the supratemporal bone is on the lateral side of the supratemporal process of the parietal, the supratemporal process of the squamosal is distinct, splenial and angular bones are present, the angular process of the dentary is well-developed, most of the teeth are tricuspid and distinctively flared, the transition from monocuspid/bicuspid to tricuspid teeth occurs at the seventh dental position on the dentary and at the fourth dental position on the maxilla. Head scales are large, the specimen presents four rows of snout scales of sub-equal size between the internasal and the anterior pair of frontal scales, there are four moderately-sized parietal scales and the most lateral scales are smaller than the median scales, two rows of post parietal scales are present, there is no enlarged lateral post-parietal scale, there are three internasal scales, there are four lorilabial scales anterior to the first lorilabial contacting the elongated sub-ocular scale, the cephalic scales lack ridges, the temporal scales are of sub-equal size and no elongated temporal scales are present, the lateral nuchal scales are smaller than surrounding body scales, the lateral body scales are the same size as dorsal and ventral scales, a prominent middorsal body crest formed by overlapping scales is present, the dorsal crest (occiput to vent) is composed of 53 scales, the tricarnate scales at the base of the first and second toes grow into comb-like fringes but are not prominent, the venter is dull and patternless, there is no scapular patch, no suprascapular blotches, no facial band, and the base of tail is laterally compressed.</p> <p> <b>Description of paratype fossil bones and corresponding bones of the holotype.</b> In addition to the holotype dry specimen, we associate, as paratypes, several fossil bones collected from the Pointe Gros Rempart 6 deposit to the type series of <i>L. roquetus</i>. These bones are described below in association with corresponding bones of the holotype specimen in order to demonstrate that both modern and fossil materials correspond to the same taxon.</p>Published as part of <i>Bochaton, Corentin, Charles, Laurent & Lenoble, Arnaud, 2021, Historical and fossil evidence of an extinct endemic species of Leiocephalus (Squamata: Leiocephalidae) from the Guadeloupe Islands, pp. 383-409 in Zootaxa 4927 (3)</i> on pages 386-389, DOI: 10.11646/zootaxa.4927.3.4, <a href="http://zenodo.org/record/4542332">http://zenodo.org/record/4542332</a>
Squamate of the Late Pleistocene and Holocene of the Guadeloupe archipelago : evolution of biodiversity and interactions with human populations
No full textL’impact actuel de l’Homme sur la biosphère affecte l’ensemble des organismes vivants et des milieux. Il est souvent considéré comme étant à l’origine de la 6ème crise d’extinction de masse. La quantification des effets de ce phénomène est cependant complexe car certains ont débuté bien avant que les scientifiques ne s’intéressent à ces questions et ne produisent des données de référence. Ce problème est tout particulièrement manifeste dans les milieux les plus fragiles, telles que les îles, dont les écosystèmes ont pu être bouleversés par l’Homme de manière très rapide et cela avant que leur biodiversité n’ait été documentée. Dans ce cas, les ossements fossiles s’avèrent être les uniques vestiges témoignant de l’existence passée de faunes parfois éteintes. Ils deviennent donc l’unique fenêtre permettant d’entrevoir la biodiversité ancienne de ces milieux. Mon travail de thèse se questionne sur la biodiversité passée au sein de l’archipel de la Guadeloupe (Antilles françaises) à travers l’exemple des reptiles squamates (lézards et serpents). L’étude de près de 40 000 ossements issus de 31 sites archéologiques et paléontologiques datant de la fin du Pléistocène (30 000 B.P.) à nos jours, a permis de mettre en évidence l’évolution de la diversité de ces vertébrés dans le temps ainsi que de leurs relations avec les différentes populations humaines. Ces résultats ont été obtenus grâce à l’utilisation de diverses méthodes (anatomie comparée, morphométries traditionnelle et géométrique, paléohistologie et archéozoologie, récits des premiers voyageurs) et grâce au développement d’approches méthodologiques spécifiques aux squamates. Les données obtenues font état de l’impact limité sur les faunes par les populations humaines amérindiennes ayant occupé la Guadeloupe pendant plus de 4000 ans jusqu’au 17éme siècle. En effet, bien qu’ayant chassé certains squamates (iguanes et améives) et probablement participé à un enrichissement de la faune, les Amérindiens ne semblent pas avoir contribué à appauvrir la biodiversité des squamates guadeloupéens. En revanche, les données fossiles plus récentes démontrent un fort impact sur les faunes de squamates exercé par les populations européennes qui colonisent ces îles à partir du XVIIème siècle. L’effet de cette seconde vague de colonisation se manifeste par la transformation morphologique de certains taxons (réduction de taille, réduction de variabilité morphologique) et par une série d’extinctions totales ou partielles d’espèces (restriction d’aire géographique). Ainsi, le taux d’extinction des squamates de Guadeloupe est estimé entre 47 et 56% depuis 300 ans. Cette vague d’extinctions s’oppose à l’apparente stabilité de la faune des squamates que révèle le registre fossile du Pléistocène et de la première moitié de l’Holocène. Ces résultats démontrent l’intérêt de l’étude minutieuse des faunes fossiles récentes pour une meilleure compréhension de l’impact de l’Homme sur son milieu au cours du temps, un domaine encore relativement peu développé, tout particulièrement pour ce qui concerne les squamates.Current human impact on the biosphere affects all living organisms and environments. This global phenomenon is often considered as the origin of the 6th mass earth extinction crisis. Yet, the quantification of the effects of this crisis can be problematic because it started long before scientists started to investigate it and to produce reference data. This issue is especially obvious in fragile ecosystems, like islands, which environments could have been quickly modified in relation with anthropogenic phenomena before their biodiversity can have been described. In this case, fossil bones are often the sole remaining remains of past ecosystems and the only possibility to study them. My PhD work is interested in squamate (snakes and lizards) past biodiversity of the Guadeloupe Islands (French West Indies). I studied more than 40 000 fossil bones of squamates from 31 archaeological and paleontological deposits dated from Late Pleistocene (40 000 B. P.) to nowadays. My study reveals the evolution of the diversity of these reptiles along with their relations with past human populations. The results are obtained using several methods (comparative anatomy, traditional and geometric morphometrics, paleohistology and zooarchaeology) and thanks to new methodological tools I developed dedicated to the study of squamate bone remains. My results show the limited impact on squamate faunas of Amerindian human populations who inhabited Guadeloupe islands during more than 4 000 years. Indeed, although these populations seem to have hunted some squamates (iguanas and ameivas) and slightly contributed to enrich squamate diversity, they do not seem to be the cause of any extinction event. At the opposite, European populations who colonized Guadeloupe Islands since the XVIIth century strongly impacted the native squamate biodiversity. These effects take the forms of morphological modification of some taxa (size reduction, reduction of morphological variability) and partial (decrease of geographic distribution) or total extinction of many taxa. Indeed, the extinction rate of squamates species in Guadeloupe during the last 300 years is estimated between 47 and 56%. This recent mass extinction phenomenon strongly contrasts with the apparent stability of the squamate diversity between Pleistocene and the first half of Holocene revealed by fossil data. These results show the interest of studying late quaternary fossil faunas to better understand the impact of Human on its environment, a field of research still largely underdeveloped especially concerning squamates
Nouvelles données archéozoologiques sur l’oppidum de Corent: Résultats de la campagne de fouille 2010
No full textInternational audienc
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Le Robert – Grotte de l’Îlet Chancel
Full text linkLa grotte de l’îlet Chancel avait été identifiée comme présentant un potentiel intérêt archéologique et paléontologique dans le cadre d’une opération de prospection et d’inventaire du karst martiniquais conduite en 2013. Cette hypothèse s’appuyait sur la configuration de ce site qui s’avère être idéale : une grotte sèche à configuration de piège sédimentaire située à faible distance de la mer. Dans le but de tester cette hypothèse, une opération de sondage archéologique a été conduite en nove..
La Trinité – Morne Castagne
Full text linkL’objectif de cette opération était de tester le potentiel archéologique et paléontologique des abris du Morne Castagne via la conduite d’un sondage dans un de ces abris. Ce morne étant l’un des rares contextes calcaires de l’île de la Martinique, il représentait une opportunité unique de pouvoir découvrir des accumulations de restes de vertébrés anciens bien préservés dans un contexte naturel. Un sondage d’un mètre carré a été pratiqué, sous le grand abri du Morne Castagne. Ce sondage a pu ê..
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