Updated

As if the West Nile-toting mosquito isn't enough to worry Mississippians, add the poisonous Latrodectus geometricus to the state's list of creepy-crawly creatures.

Dr. Jerome Goddard, entomologist with the Mississippi Department of Health, said the poisonous Brown Widow spider that is a cousin to the well-known Black Widow, is now calling the Mississippi Gulf Coast home.

"The tropical Brown Widow spider .... has recently been captured in many locations along the Mississippi Gulf Coast," Goddard said in a news release Tuesday.

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He said his office has been receiving many phone calls reporting buildings and grounds heavily infested with this type of spider.

"This spider is in the same family as the Black Widow, and is poisonous to humans," Goddard said. "I first heard of a collection of this spider at Keesler Air Force Base in Biloxi in early 2005 and figured it was probably just an isolated incident."

The Health Department said the Brown Widow can grow to 1½ inches long. It is brown or grayish-brown instead of black and has an orange-to-yellow hourglass design on its underside, as opposed to the familiar red hourglass design on the Black Widow.

"That's a dead giveaway," Goddard said. "When the hourglass design is yellowish or orange, instead of deep red, you know it is a Brown Widow."

He said there is a positive note — the Brown Widow is not as aggressive as the Black Widow. And although some scientific reports claim the Brown Widow is twice as poisonous, Goddard said that was doubtful.

"One very good medical review of 45 cases of Black Widow and Brown Widow bites showed that the symptoms of Brown Widow bites were mild and tended to be restricted to the bite site and surrounding tissues (not the case with black widows)," Dr. Goddard said. "Brown Widows will not attack if they are not bothered or made to feel threatened."

Most spiders in Mississippi are unable to puncture human skin, and if they do, their venom is not generally harmful to humans.

There are three main spider species in Mississippi that health officials worry about — the Black Widow, Brown Recluse and now the Brown Widow.

Goddard said he was unaware of the new species existing anywhere else in Mississippi.

"I've gone down to the Gulf Coast several times and looked for myself," he said. "They are, indeed, in many places."

He said the spider probably made its way to Mississippi from Florida through commercial imports of plants, food, building materials, or furniture.