|Copyright: Francisco Sales (FranciscoSales)
|Date Taken: 2006-03-14|
|Camera: Nikon Coolpix 5600|
|More Photo Info: [view]|
|Photo Version: Original Version|
|Date Submitted: 2006-03-14 19:13|
|[Note Guidelines] Photographer's Note [Portuguese]|
|THE GENUS PHONEUTRIA, PERTY 1833, wandering spiders. |
These spiders belong to the family Ctenidae where Phoneutria is one of around 40 genus and the only one knowned that have a venom potent enough to be a danger to humans.
The genus Phoneutria can be found over large parts of South America and some parts of Central America, and 5 species are described so far after a revision of the genus in 2001
Phoneutria differs from other genus in the family Ctenidae by a thick comb of hairs on the lateral edge and ventral part of the pedipalps. Phoneutria also differs from other ctenids by its unique warning display - the body and the two first legpair are kept vertical and then the spider rock from side to side horizontally.
The most famous species is Phoneutria fera that in popular literature been dubbed as the most venomous spider in the world. Its open for debate if that is truly the case but fact is they got a very potent neurotoxin, just as nigriventer have. Most people that are bitten by a member of this family is bitten by a nigriventer, mostly because the species appear in heavily populated areas like Sao Paolo and Rio de Janiero while P. fera are found for most part in the Amazon region where the poulation is less dense.
The research on Phoneutria venom is done on nigriventer and some believe that bites that been refered as fera bites most likely are in reality misidentified nigriventer bites and envenomations (pers. corr. Rogerio Bertani, Butantan Inst.)
So how dangerous are nigriventer? Deaths have occured and during the years 1926-1996 14 fatalities happened. Nowadays there are a good working serum available in Brazil that are produced on Butantan Institute in Sao Paulo.
The imidiate effects after a bite is intense local pain and swelling in the bite area, followed by serious systematic effects like irregular heart rythm, stoppage of the coagulare effects in the blood, priapism, lung edema and vomiting.
One should never take a bite lightly despite the statistics that show that the risk of dying after a bite is quite small. If you are unlucky unpleasant effects and even death can be the result and one should be extra careful if serum is not regulary available.
To give some idea of the potency of the venom the LD50 for nigriventer has shown to be 0.3 mg and for comparison in the same test showed 5.5 mg for black widow, Latrodectus mactans. Note that all LD50 results should be taken with a grain of salty so to speak.
Phoneutria are nice and interesting spiders to keep in captivity, if you have a long experience in keeping fast and aggressive spiders. If not its better to stay away from these genus because of the dangerous venom. They are easy to care for and demand not much except a big dose of common sence and much respect.
pgmoni, eruyanik, SkyF, dew77, RII has marked this note useful
Only registered TrekNature members may rate photo notes.
|You must be logged in to start a discussion.|
- [2006-03-14 20:01]
Good Macro photo,Francisco. Parabéens!
Excellent focus, colors and lighting.
Good Macro photo!!
The composition and DOF is excellent
So crisp and clear shot... Focusing and dov are perfect. I prefer keep phoneutria away from me.
See you soon...
- [2006-03-15 7:44]
hola francisco, excelente toma. que suerte encontrar esta araña en color blanco. resalta muy bien con ese fondo verde oscuro. buena exposicion. tfs, gabriel
- [2006-03-15 9:23]
Bela foto Francisco.
Vc é um cara de sorte por encontrar esses bichos diferentes.
O contraste e as cores estão muito boas.
Parabéns pela foto!!!
- [2006-03-15 11:15]
Excellent POV and sharpness on this spider, Francisco.
I can see every hair on him. Interesting pale color.
Does not seem it would camouflage him well.
TFS. : )
- [2006-03-15 13:20]
Never this spider saw, only in the directory. I know, that poisonous. A successful photo.
- [2006-03-15 16:24]
oh this one is huge, well captured. Great sharp details and excellent color. Well composed photo. TFS...Sky
- [2006-03-15 22:33]
Bonne photo macro,les détails sont excellent et l,éclairage parfait.
Félicitation et merci pour l'envoie!
- [2006-03-16 4:23]
Wonderful close up.Details,sharpness,POV,lighting and
framing are excellent.Very well done!
Recién hoy con tiempo de criticar esta foto. muy buen macro y detalles, también la composición y colores.
Esta foto la publicaste un día después que leyera en el jornal, que en Misiones murió un niño de 6 años porque el antídoto estaba vencido, y como en Argentina los casos son escasos, no hay fábricas y se tuvieron que pedir a Brasil, por lo que no llegaron a tiempo.
tu nota es excelente y me ayudó a saber más sobre esta araña.
- [2006-06-20 15:26]
Excelente composion, magnificos colores, buenos detalles, es una muy buena foto.
Gracias y espero mas fotos consejos criticas y comentarios.