askook

Articles: Sherbrooke, W. C., & Mason, J. R., 2005. Sensory modality used by coyotes in responding to antipredator compounds in the blood of Texas horned lizards.The Southwestern Naturalist, 50(2): 216-222. http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1507&context=icwdm_usdanwrc Sherbrooke, W. C., & Middendorf III, G. A., 2001. Blood-squirting variability in horned lizards (Phrynosoma). Copeia,4: 1114-1122. http://yubawatershedinstitute.org/wp-content/uploads/2015/04/Blood-squirting.pdf

https://www.futura-sciences.com/planete/actualites/zoologie-serpents-ne-sont-pas-si-sourds-ca-35539/

https://www.futura-sciences.com/planete/actualites/zoologie-serpents-ne-sont-pas-si-sourds-ca-35539/

Un des 8 nouveaux arrivants

Haemotoxic snake venoms: their functional activity, impact on snakebite victims and pharmaceutical promise British Journal of Haematology DOI: 10.1111/bjh.14591 Julien Slagboom, Jeroen Kool, Robert A. Harrison and Nicholas R. Casewell http://onlinelibrary.wiley.com/doi/10.1111/bjh.14591/full

Inbreeding avoidance in Cunningham’s skinks (Egernia cunninghami) in natural and fragmented habitat Molecular Ecology (2004) 13, 443– 447 A. J. Stow and P. Sunnucks https://www.researchgate.net/profile/Adam_Stow/publication/8923163_Inbreeding_avoidance_in_Cunningham%27s_skink_Egernia_cunningamii_in_natural_and_fragmented_habitat/links/0c96053277fdb9c3fd000000/Inbreeding-avoidance-in-Cunninghams-skink-Egernia-cunningamii-in-natural-and-fragmented-habitat.pdf

Vasotocin receptor blockade disrupts maternal care of offspring in a viviparous snake, Sistrurus miliarius http://bio.biologists.org/content/biolopen/early/2017/01/07/bio.022616.full.pdf

Late bloomers and baby boomers:ecological drivers of longevity in squamates and the tuatara Global Ecology and Biogeography, (2015) 24, 396–405 Inon Scharf, Anat Feldman, Maria Novosolov, Daniel Pincheira-Donoso, Indraneil Das, Monika Böhm, Peter Uetz, Omar Torres-Carvajal, Aaron Bauer,UriRoll and Shai Meiri http://theherpetofaunalbiologygroup.weebly.com/uploads/1/4/1/5/14155652/442-_scharf_et_al.__late_bloomers___baby_boomers_.pdf

Length–mass allometry in snakes Biological Journal of the Linnean Society, 2013, 108, 161–172 Anat Feldman and Shai Meiri https://www.researchgate.net/publication/262872508_Length-mass_allometry_in_snakes

Evaluation of sperm quality snakes Erythrolamprus poecilogyrus sublineatus (Cope, 1860) (Serpentes, Dipsadidae) Braz. J. Biol., ahead of print Epub Jan 12, 2017 A. C. Silvaa , A. S. Varela Juniorb, T. F. Cardosob, E. F. Silvab, D. Loebmannb & C. D. Corcinia http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1519-69842017005101106&lng=en&nrm=iso&tlng=en

Pheromone Communication in Amphibians and Reptiles Annu. Rev. Physiol. 2009. 71:161–176 Lynne D. Houck https://pdfs.semanticscholar.org/d1b8/dc8b43f606b0d49a3e5beb33f0f823a68bee.pdf

The brain and behavior of the tentacled snake Annals of the New York Academy of Sciences Kenneth C. Catania http://www.fbmc.fcen.uba.ar/materias/fca/seminarios/Compound%20eyes%20and%20retinal%20PNAS%202010%20SUPLEMENTARIO.pdf

Phylogenetics of Kingsnakes, Lampropeltis getula Complex (Serpentes: Colubridae), in Eastern North America The American Genetic Association. Journal of Heredity, 2017, 1–13 Kenneth L. Krysko, Leroy P. Nuñez, Catherine E. Newman & Brian W. Bowen http://www.cnah.org/pdf/88589.pdf

Off the scale: a new species of fish-scale gecko (Squamata: Gekkonidae: Geckolepis) with exceptionally large scales PeerJ 5:e2955. doi.org/10.7717/peerj.2955 Mark D. Scherz​, Juan D. Daza, Jörn Köhler, Miguel Vences & Frank Glaw https://peerj.com/articles/2955/

Article: Off the scale: a new species of fish-scale gecko (Squamata: Gekkonidae: Geckolepis) with exceptionally large scales https://peerj.com/articles/2955/

Le lézard pro du strip-tease pour échapper à ses prédateurs Des chercheurs ont identifié une nouvelle espèce d'un gecko malgache, expert pour abandonner ses écailles et mieux se glisser hors les griffes de ses prédateurs. Un «défi taxonomique»: Geckolepis, un gecko nocturne endémique de Madagascar et des Comores, est pour le moins difficile à attraper et à décrire fidèlement. Et pour cause: il a la capacité, lorsqu'on tente de le capturer, de se «dénuder» pour échapper à l'ennemi. Vous connaissiez les lézards capables de sacrifier leur queue pour sauver leur peau. Geckolepis peut quitter son manteau minéral et se carapater tout nu, pendant que le gourmand prédateur se retrouve avec... des écailles pour tout repas. Nettement moins savoureux que la juteuse chair d'un lézard frais. Dans la revue en open access PeerJ, des zoologistes allemands, américains et colombiens décrivent une nouvelle espèce de la famille, Geckolepis megalepis. Sa différenciation génétique est «forte», insistent les zoologistes, avec environ 10% de divergence par rapport à ses cousins strip-teaseurs. Mais il est surtout beaucoup plus performant dans l'art de l'effeuillage que ses cousins. Déniché dans le massif d'Ankarana, au nord de Madagascar, l'animal arbore, le long des quelque 70 mm de son corps et des 80 mm de sa queue, «les plus grandes écailles connues chez les geckos» et celles-ci «peuvent s'en aller avec une exceptionnelle facilité», admirent les auteurs. La bestiole est aussi capable de former de nouvelles écailles en quelques semaines. Chez les lézards, c'est rapide pour renouveler sa garde-robe. Source: http://www.lefigaro.fr/sciences/2017/02/07/01008-20170207ARTFIG00206-le-lezard-pro-du-strip-tease-pour-echapper-a-ses-predateurs.php

Is Hybridization a Source of Adaptive Venom Variation in Rattlesnakes? A Test, Using a Crotalus scutulatus × viridis Hybrid Zone in Southwestern New Mexico Toxins (Basel)v.8(6); 2016 G. Zancolli, T.G. Baker, A. Barlow, R.K. Bradley, J. J. Calvete, K. C. Carter, K. de Jager, J.B Owens, J. Forrester Price, L. Sanz, A. Scholes-Higham, L. Shier, L. Wood, C. E. Wüster & W. Wüster https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4926154/

Phenotypic differences in a cryptic predator: Factors influencingmorphological variation in the terciopelo Bothrops asper (Garman, 1884; Serpentes: Viperidae) Toxicon 54 (2009) 923–937 Monica Marıa Saldarriaga-Cordoba, Mahmood Sasa, Rodrigo Pardo & Marco Antonio Mendez https://www.academia.edu/22861641/Phenotypic_differences_in_a_cryptic_predator_Factors_influencing_morphological_variation_in_the_terciopelo_Bothrops_asper_Garman_1884_Serpentes_Viperidae_?auto=bookmark&campaign=weekly_digest

Alai! Alai! – a new species of the Gloydius halys (Pallas, 1776) complex (Viperidae, Crotalinae), including a brief review of the complex Amphibia-Reptilia (2016) DOI:10.1163/15685381-00003026 Philipp Wagner, Arthur Tiutenko, Glib Mazepa, Leo J. Borkin & Evgeniy Simonov https://www.academia.edu/22232902/Alai_Alai_a_new_species_of_the_Gloydius_halys_Pallas_1776_complex_Viperidae_Crotalinae_including_a_brief_review_of_the_complex

Back from the dead! Resurrection and revalidation of the Indian endemic snake genus WallophisWerner, 1929 (Squamata: Colubridae) insights from molecular data Mitochondrial DNA Part A doi:10.1080/24701394.2016.1278536 Zeeshan A. Mirza & Harshil Patel https://www.dropbox.com/s/z2debhp9frhtmyu/wallophis_Mirza_Patel_2017.pdf?dl=0

Endless forms most beautiful: the evolution of ophidian oral glands, including the venom system, and the use of appropriate terminology for homologous structures ZoomorphologyDOI 10.1007/s00435-016-0332-9 T. N. W. Jackson, B. Young, G. Underwood, C.J. McCarthy, E. Kochva, N. Vidal, L. van der Weerd, R. Nabuurs, J. Dobson, D. Whitehead, F.J. Vonk, I. Hendrikx, C. Hay & B. G. Fry https://www.academia.edu/30456256/Endless_forms_most_beautiful_the_evolution_of_ophidian_oral_glands_including_the_venom_system_and_the_use_of_appropriate_terminology_for_homologous_structures

Bite from the past: new study on boomslang venom provides insights into the death of renowned herpetologist Karl Schmidt The actual bite happened in less than a second. Dr. Karl Schmidt, an American herpetologist at the Field Museum in Chicago, had been sent a live snake to identify by his colleague, Richard Marlin Perkins (then the director of the Lincoln Park Zoo). The animal appeared to be a boomslang (Dispholidus typhus), a kind of rear-fanged African snake, but there was something a bit odd about its scales, so Schmidt and his colleagues discussed the matter as they examined the serpent. It didn’t take long for the agitated animal to decide it had had enough manhandling. “I took it from Dr. Inger without thinking of any precaution, and it promptly bit me on the fleshy lateral aspect of the first joint of the left thumb,” Schmidt wrote in his diary on September 25th, 1957. “The mouth was widely opened and the bite was made with the rear fangs only, only the right fang entering to its full length of about 3 mm.” A day later, he would be dead. Karl Schmidt, like most herpetologists and toxinologists at the time, didn’t believe that boomslang venom was anything to worry about, in spite of peer-reviewed studies that raised alarms. So rather than seek medical attention, Schmidt took to his journal, documenting his symptoms over the next 24 hours. “4:30-5:30 strong nausea, but without vomiting, during trip to Homewood on suburban train,” he wrote. “5:30-6:30 strong chill & shaking, followed by fever of 101.7°, which did not persist (blankets and heating pad). Bleeding of mucous membranes in the mouth began about 5:30, apparently mostly from gums. 8:30 PM ate 2 pieces milk toast.” By morning, after a fitful night filled with bloody urine and violent nausea and vomiting, Schmidt decided he was feeling better, and even called the museum to say he’d be at work that day. He stopped taking notes on his condition. But sadly, he took a sudden turn for the worse after lunch. He struggled to breathe as his wife frantically called their physician and emergency aid. Then his breathing stopped. Resuscitation attempts failed. Just before 3 PM on September 26th, 1957, when Schmidt arrived at the hospital, he was pronounced dead. “Schmidt was a hugely respected biologist and herpetologist,” said Nick Casewell, a senior lecturer and Wellcome Trust research fellow at the Alistair Reid Venom Research Unit at the Liverpool School of Tropical Medicine. So it’s not surprising that over the decades, many have debated whether Schmidt could have lived. If he’d only sought medical attention immediately, rather than nearly a day after the bite when symptoms were dire. But would that have even saved him? Though it’s hard to know for sure, in a new study, Casewell and his colleagues provide some answers. The researchers isolated and identified the components of boomslang venom and determined whether an antivenom similar to what would have been available to Schmidt at the time is capable of neutralizing the most devastating toxic components. Given that Schmidt described symptoms of impaired clotting throughout his ordeal, and his autopsy revealed extensive internal bleeding, it seems likely that he died from a condition physicians call consumptive coagulopathy. And not surprisingly, the scientists found deadly toxins in the venom that are also found other deadly snake venoms that kill by corrupting the blood. “Almost certainly, the toxic components responsible for the bleeding disturbances are the snake venom metalloproteinase toxins which completely dominate the venom proteome,” explained Casewell. While their presence wasn’t unexpected, the diversity of these toxins—nineteen different forms—and their overall contribution to the venom (more than 75% of the proteins in it) were a bit surprising. “Usually this kind of diversity and abundance is only found in certain vipers,” Casewell explained. Schmidt severely underestimated the potency of the young snake he was sent, and the hours he spent at home rather than in medical care almost certainly ensured his fate. But if he had sought a hospital immediately, could he have survived? The researchers did find that CroFab, a modern antivenom similar to what was available in the U.S. at the time, was able to bind much of the venom’s potent toxins even though it is made using venoms from a completely different lineage of snakes. Still, Casewell isn’t convinced. “It remains unclear whether this cross-reactivity would have translated into life-saving neutralization,” he said. But the better question is whether doctors would have even thought to use that antivenom, since it wasn’t made for snakebites from African snakes or rear-fanged ones. “Its also highly likely that Schmidt would have known that a rattlensnake antivenom was unlikely to be particularly effective against a bite by a completely distinct snake,” he noted, and therefore, he may not have instructed doctors to administer antivenom even if he had been in their care early enough for it to have possibly helped. Today, the boomslang is considered one of Africa’s most deadly snakes, and other rear-fanged species have become respected for their potent venoms. “Schmidt’s death raised the attention of the potential toxicity of non-viper and elapid snakes to the scientific community, which resulted in a number of studies in the 60s and 70s,” said Casewell. “Of course now, building on that early work, we know that colubrid snakes like the boomslang have a venom system homologous to those medically-important vipers and elapids and share a number of similar toxins, although the glands and fangs have some distinctions meaning that very few species are capable of killing people.” While the nature of Schmidt’s death has continued to draw fascination and speculation from venom community, his legacy extends far beyond the tale of his untimely end. As a herpetologist, he named more than 200 species and wrote more than 150 books. An avid reader, he built an impressive personal collection of scientific literature over his lifetime, and his library of over 15,000 titles lives on in the Karl P. Schmidt Memorial Herpetological Library at the Field Museum. He is a legend in the field, and continues to impact herpetology decades after his death. Source: http://blogs.discovermagazine.com/science-sushi/2017/01/30/karl-schmidt-boomslang-venom-study/# Article: What killed Karl Patterson Schmidt? Combined venom gland transcriptomic, venomic and antivenomic analysis of the South African green tree snake (the boomslang), Dispholidus typus http://www.sciencedirect.com/science/article/pii/S0304416517300284

Un venin de serpent très dangereux pour l’homme pourrait servir à traiter la leucémie Des scientifiques en neurosciences de la Corporation de sciences biomédicales de base de l’Unité d’Antioquia ont conclu la première phase de recherches menées pour lutter contre la leucémie en utilisant le venin de Porthidium nasutum, un serpent appartenant à une famille de reptile trouvant refuge au sein des forêts tropicales d’Amérique latine y compris en Colombie (mais aussi au Mexique, en Amérique centrale et en Équateur), où il est connu sous le nom de « Patoco », « nariz de cerdo », « veinticuatro », ou encore « patoquilla ». Sebastian Estrada, directeur du Serpentarium de l’Université d’Antioquia, a précisé que ce serpent est surtout connu de façon populaire sous le nom de Patoco et il est présent dans les zones d’Urabá, Bajo Cauca et de la région andine. Ils mangent des lézards et les femelles adultes mesurent entre 60 et 70 centimètres. Les mâles sont plus minces et plus petits. Les recherches scientifiques ont été réalisées par des spécialistes qui sont parvenus à une caractérisation moléculaire et biochimique et ont ainsi isolé le poison pour obtenir une toxine qui a été baptisée Nasolysina-1. Avec des techniques in vitro, l’équipe a réussi à injecter la particule dans des cultures de cellules et les corps cellulaires aqueux de la leucémie lymphoïde chronique et myéloïde. La procédure a permis de découvrir que la toxine induit une mort cellulaire et une nécrose (dégénérescence du tissu cellulaire) de manière sélective, affectant seulement la mort des cellules cancéreuses, dans le cas de la leucémie, sans endommager les lymphocytes ou les cellules saines. Le professeur, biologiste et docteur en neurosciences, Carlos Velez Pardo a affirmé que le projet est né d’une discussion qu’il a eue avec un autre collègue étudiant l’ophidisme et les effets du venin de scorpion sur certaines pathologies. « Nous nous sommes assis pour parler et et comme j’avais une l’expérience dans les neurotoxines, nous avons réclamer auprès du vivarium de l’Université du venin de Porthidium nasutum afin d’évaluer son activité antileucémique. Ensuite, au cours du premier test que nous avons fait, nous avons réalisé qu’il induit un type de mort cellulaire et avec la façon dont nous avons l’avons utilisé, on a fait une proposition pour un projet qui permettrait d’analyser laquelle de ces molécules produit un poison permettant d’avoir une activité spécifique pouvant induire la mort de ces cellules ». Marlene Jimenez, biologiste moléculaire doté d’un doctorat en neurosciences a également participé à la recherche, elle a affirmé que, pour le moment, l’étude se trouve au stade in vitro, lors d’une deuxième étape, des tests auront lieu avec des souris de laboratoire, elle a affirmé que l’équipe s’attendait à une réaction similaire avec les molécules extraites de cette toxine ne nuisant pas aux cellules normales, mais uniquement à celles malades contribuant ainsi à la lutte contre ce cancer. Le chef de projet et professeur à l’Université d’Antioquia, Carlos Velez Pardo, a déclaré que le poison a été extrait manuellement à partir de 45 espèces de serpents de l’institution. Par la suite, par des techniques in vitro, les chercheurs ont injecté la toxine dans les cellules cancéreuses de la leucémie causant leur mort sans endommager les cellules saines. « En utilisant un modèle de cellules de leucémie aiguë, on a permis d’établir que ce venin de serpent induit une mort cérébrale dans les cellules cancéreuses », a déclaré le chercheur. Après avoir extrait le poison et l’avoir purifié avec une caractérisation biochimique, la toxine a été baptisée Nasulysina 1. Cette substance devient alors porteur d »un important espoir thérapeutique pour les malades atteints de leucémie. Source: http://www.actulatino.com