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ugo02

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  1. ugo02

    canebreak rattle

    uncommonly beautiful specimen, from a friend : Crawford Hicks
  2. ugo02

    ASIAN PIT VIPERS UPDATE

    sorry, it was at His facebook page, anyway here what He wrote : Just when you thought you were getting used to the new (2004) names for the former Trimeresurus pitvipers, it is all change again –well not exactly, but there have been some important changes brought about my a recent paper (David, Vogel & ...Dubois 2011 On the need to follow rigorously the Rules of the Code for the subsequent designation of a nucleospecies (type species) for a nominal genus which lacked one- the case of the nominal genus Trimeresurus Lacépède, 1804. Zootaxa 2992:1-51.). I will summarize what folks interested in these pitvipers need to know but to make this bitter pill easier to swallow I have attached a photograph of the Lesser Sunda pitviper (Trimeresurus insularis, formerly Cryptelytrops insularis, the species at the root of the explanation that follows). Trimeresurus is a large genus of arboreal and terrestrial pitvipers (currently 48 species) distributed in Asia from Tibet to Timor. The type species has long been thought to be Trimeresurus gramineus (Shaw, 1802) the common green pitviper of India. The genus was split into seven genera (Malhotra & Thorpe 2004 A phylogeny of four mitochondrial gene regions suggests a revised taxonomy for Asian pitvipers (Trimeresurus and Ovophis). Molecular Phylogenetics and Evolution 32: 83 –100.] resulting in the resurrection of three genera: Cryptelytrops (Cope, 1860), Parias (Gray, 1849), and Peltopelor (Günther, 1864), and the description of three new genera: Himalayophis, Popeia and Viridovipera (Malhotra & Thorpe, 2004), to which was added another genus (Sinovipera, Guo & Wang, 2011). Since Trimeresurus gramineus was recognized as the type species the pitvipers most closely related to it remained in the genus Trimeresurus. Reptile keepers were probably just getting used to Cryptelytrops albolabris, Parias flavomaculatus, Popeia popeiorum and Vividovipera gumprechti. But this has all changed, in two ways, as a result of the David, Vogel & Dubois, 2011 paper. Firstly the authors determined that the type species of Trimeresurus is not T.gramineus from India, but T.viridis (Lacèpéde, 1804) from Timor. I won’t go into how they determined this, it takes around 35 pages, you will just have to trust me on this, or obtain a copy of the paper from the Zootaxa site for $12.60 [http://www.mapress.com/zootaxa/taxa/Reptilia.html]. Trimeresurus viridis is the species is the pitviper we currently call Cryptelytrops insularis, the name T. viridis has not been used since 1899 and the popularity of insularis means that it is likely to remain the valid name, even though T. viridis is much older (Law of Stability over-rides Law of Priority). This means it is the species in the Cryptelytrops group that should bear the name Trimeresurus, not the species in the T. gramineus group. Therefore the following species should be referred to as Trimeresurus rather than Cryptelytrops (albolabris, andersoni, cantori, cardamomensis, erythrurus, fasciatus, honsonensis, insularis, kanburiensis, labialis, macrops, purpureomaculatus, rubeus, sepentrionalis and venustus) while the species placed retained in Trimeresurus by Malhotra and Thorpe, or subsequently placed there by other authors, (gramineus, andalasensis, borneensis, brongersmai, malabaricus, puniceus, strigatus, trigonocephalus and wiroti) are in need of a new generic name. The oldest name available is Craspedocephalus (Kuhl, 1824). So what was Cryptelytrops is now Trimeresurus, and what was Trimeresurus is now Craspedocephalus. The species in the genera Himalayophis Parias, Peltopelor, Popeia, Sinovipera and Viridovipera were unaffected. Following so far, because they had not finished and so nor have I. The authors then began a discussion about genera and subgenera. Malhotra and Thorpe (+ Guo and Wang) had split Trimeresurus into eight different genera, eight genera more closely related to one another than any of them were to other Asian pitviper genera such as Ovophis or Tropidolaemus, or to American pitviper genera of course. This close relationship between these eight genera is invisible if they remain at the generic level. How can you spot the odd one out in a list of genera: Cryptelytrops, Trimeresurus, Ovophis, Viridovipera, the close relationships of three of these, to the exclusion of Ovophis, is invisible if they all have the same status as genera. But if these closely related taxa are demoted to subgenera within the all-encompassing genus Trimeresurus, then their close relationships become apparent once more, clearly taxa in Trimeresurus is more closely related to other taxa in Trimeresurus than to taxa outside Trimeresurus, ie. Ovophis, Protobothrops, Bothrops. This is what the authors did, the reduced Trimeresurus, Cryptelytrops, Parias, Peltopelor, Popeia, Sinovipera and Viridovipera to subgenera of Trimeresurus. The result of this change is that if you are writing a binomial name (genus-species) then all these species should once again become Trimeresurus spp., but now the inter-specific relationships are lost, it is not apparent that T. albolabris is more closely related to T. insularis than it is to T. trigonocephalus or T. popeiorum. The way around this is to include the subgeneric name in brackets ie. Trimeresurus (Trimeresurus) insularis, Trimeresurus (Craspedocephalus) trigonocephalus, Trimeresurus (Popeia) popeiorum, etc. Someone folks will respond to all this with derision aimed at the taxonomists concerned, but taxonomy is by its very nature in a continual state of flux, we have to live with that. Taxonomy deals with continually evolving organisms, organisms that have long evolutionary histories going back into the mists of time (vipers evolved over 54 MYA = million years ago, while we (Homo sapiens) appeared less than 0.5 MYA). What is more, taxonomy is now intended to be phylogenetic (based on closeness of relationships) rather than it was in the 18th & 19th Centuries when it much more phonetic (based on closeness of resemblance). Many snake groups are so recent (yes, 54 MYA is recent) that they have poor fossil records compared to say dinosaurs, but the even more recent advent of molecular techniques that enable us to look back into the past and determine, not only which species are closely related but also how far back their family-tree diverged, have opened up new horizons for taxonomists. These techniques have revolutionized what we know about the relationships of many groups of organisms and subsequently led to some pretty major changes in the taxonomic arrangement of those organisms. Within the reptiles the gecko family Phyllodactylidae was described based on molecular techniques, as was the recent blind snake family Gerrhopilidae. These techniques not only allow taxonomists to determine which organisms are most closely related, and how far back they diverged but they are also allowing scientists to determine the route by which modern species got to where they live today, riding on the back of chunks of Gondwanaland, but that is above and beyond what I am trying to explain here, back to the pitvipers of Trimeresurus. With with changes in taxonomy there will always be changed in nomenclature. The Rules that govern the composition and use of all names in zoology are laid down by the ICZN (International Commission of Zoological Nomenclature), but bear in mind scientists have been collecting and descripting species, including pitvipers, for over 250 years and some of the specimens, manuscripts and records from so long ago were less carefully compiled or curated than we like today and several major museum collections have been destroyed by fire or war. Sorting all this out, finding order in chaos, is often a labour of love, and a lot of what we call species today depends on people like David, Vogel & Dubois, and their colleagues, delving into detective work deep going into the past.
  3. ugo02

    ASIAN PIT VIPERS UPDATE

    Grazie Marie-Laure ok
  4. Good morning Everybody, only 2 words about the Asian Pit Vipers : i don't remember the name of that Mate who commented here 1 of my pics, correcting the scientific name i posted . As I told Him, despite the 1.500 dollars of the book it purchased, that book is crap! and here it is : everything changed again in the classification of Asiatic Pit Vipers (for more infos, please go to the web page of Mark O'Shea) and read the new changments in the new book here : Hope U r experienced a sweet time. all my best Urs always ugo
  5. Chance, I feel free to speak with U only : it is a Forum for or against snakes?; for what all U post here it is unclear. The only posts all of U do about venomous are AGAINST. Please go around other Forums and give a sight, a Guest here could laugh to die. The only other thing i don't like is the habit of arguing for days, quotation by quotation, about.......fried air, giving own assuptions as 'scientific' truths. I was fully sincere as U wer3e with me. Now U can bann me, the important is U know and think about what i wrote. What are the infos the Reader can take, from the Forum, to improve? all my heart ugo
  6. Johannes : i was only naughty. anyway what Italians are is under everybody's eyes; surely I AM THE STUPID, but not as much as sensationalists. cheers ugo
  7. vous êtes vraiment distrait française: tout perdu, sauf un goût pour le sensationnalisme. euh, combien de bébés cette année en France en voiture ou oubliés au supermarché? Google est responsable de la mauvaise traduction, je passe en revue les mauvaises pensées et les mauvaises ciao, ugo
  8. ugo02

    few more pics for NINA

    Marie, Laura, comme toujours, vous avez raison. J'ai dit Misty qu'elle est droite, et franchement, j'admire son savoir et sa connaissance du produit, c'est juste que .... Je ne m'en fous! baisers
  9. ugo02

    few more pics for NINA

    Cosa c’è in un nome? Ciò che noi chiamiamo rosa, Chiamata con un altro nome, profumerebbe come dolce. Così Romeo, se non si chiamasse Romeo, Manterrebbe quella cara perfezione che possederebbe, Senza quel nome. Romeo butta via il tuo nome; Shakespeare, Juliet, balcony scene and read again Smith (1943) and Warrell (1992) Cheer
  10. ugo02

    few more pics for NINA

    MYSTY : yes Sir, U r right. it is if U trust the work by Grumpecht, Tillack, Orlow, Captain, Rayabow : "Asian Pit Vipers" considered the 'Bible' about Trimeresurus only i don't trust it The matter lies far long back, with Boulenger, Anderson and Theobald. when 'purpureomaculatus' meant what it means : red spots on the body. No needs to recall U about how many snakes changed name & assigniment recently,only to come back to their previous ones a few years later. cheers
  11. ugo02

    mon amethyste

    Congrats, very nice
  12. Marie-Laure : L'essentiel est qu'il n'y a aucun remède pour les gens comme moi qui sont nés stupide (je vais vous parler dès que possible avec mon Créateur), et je voudrais voir ce forum plus vivant, peut-être un rassemblement annuel pourrait aider. Ensuite, je suggère à tout le monde à «adopter» une paire de soi-disant «serpents moins importante» (Storer, Duberria, Farancia., Erpeton ..... sans fin), et il serait intéressant ..et. utile. Et enfin, qui Chance me rappelle Quelqu'Un tellement Spéciaux .........
  13. Congrats JAY : really wonderful lizards. it was the Bugs/Frogs/Varans year at Hamm . and, perhaps, something legged is behind the corner here, too........but not varans, i have not the right feeling, unfortunately as U know V. dumerili and V. flavescens are my preferred all my best
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