Re: Assam: 2 people dead after swarms of venomous spiders invade Indian town
From; ‘Tarantulas’ invade Assam town, ‘kill’ two
Manimugdha S Sharma, TNN | Jun 3, 2012, 03.35AM IST
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Then on May 22, a team of life scientists from Dibrugarh University and Gauhati University arrived in Sadiya. Led by Dr L R Saikia, head, Department of Life Sciences, Dibrugarh University, the team camped in the trouble spot for two days and nights and collected specimens. "As of now, we cannot give a specific name.
It's similar to the tarantula, but it could be a whole new species. There aren't any arachnologists in the northeast, so it will take us a while to identify it. But whatever the species, it is a highly aggressive spider. It leaps at anything that comes close. Some of the victims claimed the spider latched onto them after biting. If that is so, it needs to be dealt with carefully. The chelicerae and fangs of this critter are quite powerful; but it's too early to declare it a killer spider. In fact, we are yet to test its venom and find out the toxicity," says Dr Saikia.
"We cannot say for sure that the fatalities were due to the venom; it could have been because of allergic reaction to the venom, which triggered cardiac arrest in both the victims. But all the bite patients first went to witch doctors, who cut open their wounds with razors, drained out blood and burnt it. That could have also made them sick. Also, we didn't administer any antivenin dose, as we were not sure if the spider was venomous," says Dr Anil Phatowali, superintendent, Sadiya Civil Hospital.
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Dr Ratul Rajkhowa of the zoology department of Cotton College, Guwahati, has seen the spider. In fact, one of the dead creatures has been preserved in the department laboratory.
He echoes Dr Saikia's views but says it's too early to call it a tarantula. "It could be the black wishbone or a species related to it. Or may be a species related to the funnel-web spider.
Whatever it is, it is definitely new to the area. Assam doesn't have venomous spiders, it never had any throughout history, or there would have been some document, text or art that depicted this spider. People wouldn't have panicked like this; they are scared because they have seen something like this for the first time and don't know how to deal with it. They are used to the common house spider, which runs away when you even snap your finger close to it. But this spider attacks if you try to scare it off. Those who were bitten have said that when they tried to shoo it off, it leapt at them and buried its fangs."
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On May 28, the spider allegedly appeared in Nalbari, Lower Assam—a good 600 km away from Sadiya—and bit a woman. The woman not only trapped the spider, she was also sane enough to come to a hospital instead of visiting a witch doctor. When TOI contacted the deputy commissioner, Lalit Gogoi, on May 31, he informed that the woman took the spider back home after treatment. It didn't occur to the babus that the specimen should have been retained and sent for lab testing.
One thing that is unexplained is how the black spider appeared in swarms. "A certain anomaly in conditions may provoke an unusual surge in breeding populations. Swarms of spiders are rare, although they have been reported, usually after flooding when the spiders search for dry and higher ground," says
British naturalist Dr Vejay K Singh, popularly known as Dr Venom. He has heard about the spider menace and says he would like to come down and check the spider himself.
TOI had showed him an image of the spider, to which he responded: "This is indeed a theraphosid spider or more commonly called tarantula. Most likely from the genus selenocosmia or lyrognathus, but more probably the former. The spiders are nocturnal, which explains why the attacks took place at night. The selenocosmia are aggressive spiders and will bite readily when provoked. However, they are not a social spider like the poecilotheria (tree spiders) which occur in south India and Sri Lanka. So a suggestion of swarms is puzzling. Perhaps, it is more likely to be a freak case of a population sprawl in the area. And although aggressive by nature, these spiders are not considered dangerous with regards to toxicity, and are unlikely to cause a fatal bite in a healthy individual."
Dibrugarh University has, meanwhile, sent spider specimens to Indian Society of Arachnology, Maharashtra, for identification. Their report pending and without any spider specialist visiting the region, the truth about the mysterious spider attacks in Assam continues to be covered by a cobweb.
manimugdha.sharma@timesgroup.com
http://timesofindia.indiatimes.com/...-Assam-town-kill-two/articleshow/13753398.cms
