Custom Search
Protected by Copyscape Duplicate Content Tool

Tuesday, December 18, 2007

BROWN RECLUSE

The Brown Recluse Spider, (Loxosceles reclusa), is a well-known member of the family Sicariidae (formerly placed in a family "Loxoscelidae"). It is usually between 6–20 mm (¼ in and ¾ in) but may grow larger. It is brown and sometimes an almost deep yellow color and usually has markings on the dorsal side of its cephalothorax, with a black line coming from it that looks like a violin with the neck of the violin pointing to the rear of the spider, resulting in the nickname "fiddleback spider" or "violin spider". Coloring varies from light tan to brown and the violin marking may not be visible.

According to wikipedia, this spider is not aggressive and usually bites only when pressed against human skin, such as when tangled up within clothes, bath towels, or in bedding. In fact, many wounds that are necrotic and diagnosed as brown recluse bites can actually be Methicillin-resistant Staphylococcus aureus (MRSA). Actual brown recluse bites are rare. Brown recluse bites may produce a range of symptoms known as loxoscelism. There are two types of loxoscelism: cutaneous (skin) and systemic (viscerocutaneous).

Most bites are minor with no necrosis. However, a small number of bites produce severe dermonecrotic lesions, and, sometimes, severe systemic symptoms, including organ damage. Rarely, the bite may also produce a systemic condition with occasional fatalities. Most fatalities are in children under 7 or those with a weaker than normal immune system.

A minority of bites form a necrotizing ulcer that destroys soft tissue and may take months and possibly (very rarely) years to heal, leaving deep scars. There have been no known cases of actual brown recluse bite sites taking years to heal; those that do can usually be attributed to a systemic infection or disease such as diabetes. The damaged tissue will become gangrenous and eventually slough away. The initial bite frequently cannot be felt and there may be no pain, but over time the wound may grow to as large as 10 inches (25 cm) in extreme cases. Bites usually become painful and itchy within 2 to 8 hours, pain and other local effects worsen 12 to 36 hours after the bite with the necrosis developing over the next few days.

Picture and Information courtesy of www.wikipedia.com
Picture: Brown Recluse on a Quarter (Photo courtesy of the University of Nebraska)

Monday, December 17, 2007

A WOLF SPIDER BITE

On a personal note, I believe that the large spiders we commonly see crawling in houses in the Philippines belong to a specie of Wolf Spiders. For one, they don't build intricate webs to capture their prey. They hunt them down like wolves. They set up ambush to catch them and feed on them.

I really have not seen any one gets bitten by a Wolf Spider but in one of my surfs, I have chanced upon this particular picture about an alleged wolf spider bite. I would like to share it with you. Here below:

It looks very painful. If you can observe, the redness around the bite wound shows that there is a swelling. It is still dangerous to touch this particular arachnid.

Saturday, December 15, 2007

WOLF SPIDERS

Wolf Spiders are members of the family Lycosidae, so named because their method of hunting is to run down their prey. They are robust and agile hunters that rely on good eyesight to hunt, typically at night.

There are several genera of wolf spider, ranging in size from 1 cm to 8 cm. They have eight eyes arranged in three rows. The bottom row consists of four small eyes, the middle row has two very large eyes (which distinguishes them from the Pisauridae), and the top row has two medium-sized eyes. They depend on their eyesight, which is quite good, to hunt. Their sense of touch is also acute. They are mostly harmless to humans; a bite may cause some itching, but is itself nothing deadly or major.
Hogna is the genus with the largest of the wolf spiders. Among the Hogna species in the U.S., the nearly solid dark brown H. carolinensis is the largest, with a body that can be more than one inch long. It is sometimes confused with H. helluo which is somewhat smaller and entirely different in coloration.


The Carolina Wolf Spider in particular make deep tubular burrows in and around which they lurk much of the time. Others, seek shelter under convenient rocks and other such shelters as nature may provide. They may wander from place to place, and are therefore more likely to be the ones attracted into human habitation when the weather starts to turn colder in autumn.
There are many smaller wolf spiders. They patrol our pastures and fields and are an important natural control on harmful insects.

The wolf spiders bite in defense. Some South American species may give bites that are medically significant. However, in general their presence works much more in favor of humans wherever they are found.

One strange thing about female Wolf Spiders is that they carry their eggs along with them in spherical, silk egg sacs attached to their spinnerets. After the eggs hatch, the multitude of tiny spiders climb onto their mother's abdomen, where she carries them for about one month. This high degree of parental care is unusual in spiders. That is more like a mammal.

Pictures and Information courtesy of http://www.wikipedia.com/


In the Philippines, we also have a Wolf Spider. It’s Tagalog name is Gagambang Lobo.
Identifying marks: The abdomen is oval. The legs are long and tapered. The colors are usually dull, with gray, brown, and black predominating. They do not build webs but catch their prey directly. They enclose their eggs in a silken sac attached on the females’ posterior end of their abdomen. After hatching, the young (spider lings) cling to the abdomen of the female.Food: An aggressive hunter, it searches plant and water surface for prey such as plant hoppers, leafhoppers, caseworms, leaf folders, whorl maggots, newly hatched larvae, and moths of stem borers. It consumes 7-45 hoppers per day. It is the major predator of plant hoppers and leafhoppers. Spider lings also attack plant hopper and leafhopper nymphs.

Friday, December 14, 2007

BLACK WIDOW


The Black Widow Spider (Latrodectus spp.) is a spider notorious for its neurotoxic venom. It is a large widow spider found throughout the world and commonly associated with urban habitats or agricultural areas. Although the name 'black widow spider' is most commonly used to refer to the three North American species best known for their dark coloration, black hair and red hourglass pattern, occasionally it is applied to several other members of a the Latrodectus (widow spider) genus in which there are 31 recognized species including the Australian red-back, brown widow spider (sometimes called the gray widow), and the red widow spider. In South Africa, widow spiders are also known as the button spiders.

Currently, there are three recognized species of black widow found in North America: The southern black widow (L. mactans), the northern black widow (L. variolus), and the western black widow (L. hesperus).



The spider Latrodectus tredecimguttatus, commonly known as the European or Mediterranean black widow, malmignatte spider, or karakurt (Russian: каракурт, or steppe spider), is one of the widow spiders in the genus Latrodectus. This species is commonly found throughout the Mediterranean region, ranging from Spain to southwest and central Asia.


The Red-Back Spider (Latrodectus hasselti) is a potentially dangerous spider native to Australia. It resembles a Black widow spider. It is a member of the genus Latrodectus or the widow family of spiders, which are found throughout the world. It is easily recognisable by its black body with prominent red stripe on its abdomen. Females measure about a centimetre in length while the male is smaller being only 3 to 4 milimetres long. The redback spider is one of few animals which display sexual cannibalism while mating.

Redbacks, along with Australasian funnel-web spiders (a category of spider which includes the notorious Atrax robustus, or Sydney funnel-web spider), are the most dangerous spiders in Australia. The redback spider has a neurotoxic venom which is toxic to humans with bites causing severe pain. There is an antivenom for redback bites commercially available.


The Brown Widow spider (Latrodectus geometricus), is one of the widow spiders in the genus Latrodectus. It is a "cousin" to the more famous black widow spider. The brown widow is found in parts of the southern United States (including Florida, Alabama, California, Louisiana, Mississippi, Georgia, Tennessee, and Texas); as well as in parts of Australia, northeast USA and South Africa. The origin of this species is uncertain, as specimens were independently discovered in both Africa and in the Americas. They are usually found around building in tropical areas.

The Brown Widow has a medically significant neurotoxic venom. Dr. G.B. Edwards, a University of Florida arachnologist claims that brown widow venom is twice as potent as the black widow venom but is usually confined to the bite area and surrounding tissue, as opposed to the Black Widow. Other sources say that the brown widow is less venomous. Regardless, people who have been bitten typically describe the experience as very painful and extreme care should be taken when working or playing in the areas they inhabit.

Pictures and Information courtesy of http://www.wikipedia.com/

Thursday, December 13, 2007

FUNNEL-WEB SPIDERS


Australasian funnel-web spiders are venomous spiders of the family Hexathelidae. These spiders are found in two genera of the family: Hadronyche (which is not associated with any known human fatalities) and Atrax (which probably have killed 13 people). They are notorious for the inclusion of the Sydney funnel-web spider (Atrax robustus), native to eastern Australia. There are other genera in family Hexathelidae, but these do not have the notorious reputation of the Australasian funnel-webs.

These spiders are medium-to-large in size, with body lengths ranging from 1 cm to 5 cm (0.4" to 2"). They are darkly coloured, ranging from black to brown, with a glossy carapace covering the front part of the body. Some of these spiders greatly resemble tarantulas. Like the related diplurid spiders, the hexathelids generally have long spinnerets; this is especially true of A. robustus.

Like other Mygalomorphae, (also called the Orthognatha an infraorder of spiders that includes the true tarantulas), these spiders have fangs which point straight down and do not cross each other. They have ample venom glands that lie entirely within their chelicerae. Their chelicerae and fangs are large and powerful. Although they are rather small compared to the true tarantulas, they should not be handled without taking substantial precautions, because their fangs have been known to penetrate fingernails and soft shoes, resulting in dangerous bites.
Funnel-webs are probably one of the three most dangerous spiders in the world and are regarded by some to be the most dangerous.

There have been 26 recorded deaths in Australia in the last 100 years from spider bites. Bites from funnel web spiders have caused 13 deaths (seven in children). In all cases where the sex of the biting spider could be determined, it was found to be the male of the species. Most victims were young, ill or infirm.

Pictures and Information courtesy of http://www.wikipedia.com/

Wednesday, December 12, 2007

BRAZILIAN WANDERING SPIDER


The Brazilian Wandering Spider (Phoneutria spp.) or Armadeira (as it is known in Portuguese) is an aggressive and highly venomous spider named as such because it was first discovered in Pantanal, Brazil though this genus is known to exist elsewhere in South and Central America. This spider is a member of the Ctenidae family of wandering spiders. The Brazilian wandering spider appeared in the Guinness Book of World Records 2007 for the most venomous animal.

These spiders are notorious both due to their toxic venom, and because they are not reluctant to attack people who appear threatening. Bites from these spiders may result in only a couple of painful pinpricks to full-blown envenomation. In either case, people bitten by a Phoneutria or any Ctenid should seek immediate emergency treatment as the venom is possibly life threatening. The Phoneutria fera and nigriventer are the two most commonly implicated as the most virulent of the Phoneutria spiders. The Phoneutria not only has a potent neurotoxin, but is reported to have one of the most excruciatingly painful envenomations of all spiders due to its high concentration of serotonin.

The wandering spider is so-called because it wanders the jungle floor, rather than residing in a lair or maintaining a web. This attribute is another reason it is considered so dangerous. In densely populated areas, Phoneutria species usually search for cover and dark places to hide during daytime, leading it to hide within houses, clothes, cars, boots, boxes and log piles; thus generating accidents when people disturb it. Regionally in the Mid-Atlantic US, this spider is sometimes known as the "Jerry's blue-fanged spider" because of the blue hair covering its lethal fangs. Its other common name - the "banana spider" - as attributed because it is occasionally found as a 'stowaway' within shipments of bananas.

I have encountered a lot of huge banana spiders too here in our garden since we have banana trees around. Perhaps those are similar species.

Picture and Information courtesy of http://www.wikipedia.com/

Monday, December 10, 2007

THE UNTAME DANGEROUS CRAWLERS

On the left, a spider in an attack position:
Contrary to popular belief, the most venomous spiders are not tarantulas although are frequently confused with them. According to wikipedia, there is an urban legend that deadly varieties of tarantulas exist somewhere in South America. Tale-tellers make this claims, however, without identifying the particular spider.

A probable specie they are reffering to is the dangerous Brazilian Wandering Spider (Phoneutria nigriventer), as it is sometimes found hiding in clusters of bananas and is one of several spiders called the "banana spider." It is not a tarantula but it is fairly large (4-5 inches long), somewhat hairy, highly venomous to humans, and is regarded as aggressive. Another dangerous type of spider confused with tarantulas are the venomous Funnel-Web Spiders, which despite their name are not theraphosids (true tarantulas). The best known of these is the Sydney Funnel-Web Spider (Atrax robustus), a spider which is aggressive, highly venomous, and prior to the development of antivenom in the 1980s, was responsible for numerous deaths in Australia. These spiders are members of the same suborder as the true tarantulas, but are not found in family Theraphosidae.

Of course, we cannot forget the Widow Spiders: the Southern Black Widow (L. mactans), the Northern Black Widow (L. variolus), and the Western Black Widow (L. hesperus) which experts consider as highly venomous types of spiders including the Mediterranean Black Widow. Another dangerous specie of spider is the Brown Recluse Spider. There have been reports of death due to its venomous necrotic bites. In the medical literature, numerous other spiders have been associated with necrotic bites like the Hobo Spider, the White-tailed Spider, and the Yellow Sac Spider and the Red-Back Spider.

Maybe many readers wonder why all of a sudden, I fill my blogs with all sorts of spiders and tarantulas. I must admit, I have arachnophobia. I just want to learn more about these creatures and share what I have learned with everyone who may be battling with the same fear. Maybe this fear is totally senseless after all. My next blogs may feature the not so tame species which are not suitable for pets.

Information courtesy of http://www.wikipedia.com/

Friday, December 7, 2007

THE GOLIATH BIRD-EATER

The largest known specie of tarantula is the Goliath Bird-Eating Tarantula. Experts say that it is harmless to humans just as most species of tarantulas although they still carry venom in their fangs and they bite humans when threatened but the venom just causes swelling and mild pain for a few hours just like a wasp sting. Tarantulas may bite usually in self-defense and do not always carry venom. Experts call it "dry bite".

The biggest Goliath Tarantula on record had a leg span measuring approximately one foot long with fangs measuring 1 inch long! That's huge! What is most dangerous about the Goliath Bird-Eater is its ability to flick urticating hair at any creature it perceives as a threat, including humans. Those tiny, almost invisible pieces of hair are extremely irritating to the skin and can cause serious problems if they got into delicate mucous membranes around the eyes and mouth. That is why experts do not advice this particular specie as pets not unless you are a professional tarantula handler.

Previously in my blogs, I have written that tarantulas are quiet apartment pets. Well, I have just discovered a fascinating ability of Goliath Bird-Eaters to make a loud noise. We do not normally associate spiders with noise, as we do with dogs. We see spiders silently, stealthily crawling across walls, ceilings and floors. However, when threatened, the Goliath Bird-Eater is capable of making a loud hissing noise by rubbing bristles on its legs together. Experts call it stridulation. A stridulating Goliath can produce a noise you can hear up to 15 feet away!


Tarantulas do not have a set of teeth for chewing their meals so they inject digestive juices onto their victim. These digestive juices break down the soft tissues so that it can swallow up its meal. When finished, they leave they prey with only bones, skin, fur or feathers.

The Goliath Bird-Eater has a reputation of taking young birds from their nests for its meal thus, the name "bird-eater". Like most tarantulas, It also feeds on frogs, small snakes, beetles, lizards, and even bats.

On National Geographic TV special, they illustrated the methods used by some Amazonian peoples to hunt and cook tarantulas. A tarantula was captured by holding it down with a stick and its legs were then bent upward and bound together. The creature was then roasted alive in a folded leaf. On that show, the American participant tasted the meat and commented that it reminded him of shrimp. The Goliath Bird-Eater tarantula (Theraphosa Blondi) is considered a delicacy by the indigenous Piaroa of Venezuela.

Picture and Information courtesy of http://www.extremescience.com/

Wednesday, December 5, 2007

COBALT BLUE

On the left is the Cobalt Blue Tarantula (Haplopelma lividum), which is a specie that is native to Myanmar and Thailand. It is quite aggressive and so experts recommend it only as a pet to experienced and well-informed tarantula enthusiasts.

This particular tarantula is also an obligate burrower and generally very shy. It does not possess urticating hairs so it relies more on biting for defense.

Typical care for this specie requires 6 to 8 inches of substrate and a pre-formed burrow near the glass if you ever want a chance to observe it. However, once it has become comfortable in its new home, it tends to spin a large amount of webbing to obscure vision. This specie is largely regarded as a "pet hole" since once it has established a burrow it will generally stay underground and not be seen.

It looks cool with its brilliant blue coloring but experts warn that this kind of tarantula must be treated more as a living art and never handled because it is extremely aggressive and possesses a painful bite.

I guess, if you need to hide something very important, you can hide it inside its burrow. I’m sure no one could steal it without getting a very painful bite first. Haha…

Information courtesy of http://www.wikipedia.com/
Pictures courtesy of: http://www.bighairyspiders.com/

For more exciting pictures of the Cobalt Blue Tarantula, you may click on the links below. They are cool. Promise!

Related Posts Plugin for WordPress, Blogger...