Monday, June 21, 2010

Dimorphic Jumping Spider (Maevia inclemens)

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Maevia inclemens is a relatively common and colorful jumping spider of North America. Sometimes it is referred to as the Dimorphic Jumping Spider or Blackbodied Jumping Spider.

The species' common name refers to the two different male forms that occur: One is black with yellowish small tufts of black hair on the cephalothorax. The second form, which is grayish with red, white and black markings, resembles the female, which has faint V-shaped markings and a paler abdomen. I really like the yellow palps and zebra striped legs on this little male.

This species is common in the USA. It ranges from New England south to Georgia and west to Nebraska and Oklahoma. It is also found in parts of Canada, for example in southern Quebec.

M. inclemens is the type species for the genus Maevia. The species name is derived from Latin inclemens "cruel, harsh".

Raynox DCR-150 and Raynox DCR-250 stacked and mounted on my Panasonic Lumix FZ8.

Saturday, June 19, 2010

Wolf Spider (Hogna helluo)

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This is Hogna helluo. It is the second largest species of wolf spider in the United States. I've been looking for one of these for the longest time, and today while I was out fossil hunting, I found one. This gal was about the size of a half dollar, about an inch and a half in diameter, including legs. Definitely the largest wolf spider I have ever seen.

The carapace of Hogna helluo is characterized by a clearly defined medial stripe from a point between the middle pair of eyes nearly to the point at which the carapace joins the abdomen. The abdomen has a broader light stripe with a darker narrow and tapering form like the head of a lance or a stone arrow point. The underside of the cephalothorax is solid black, but the underside of the abdomen may be spotted with lighter colored patches.

This species does not dig tunnels but may create shelters under rocks and similar natural features. H. helluo frequently enters houses with the arrival of lower temperatures in autumn. They are inside only in search of warmer temperatures and make every possible effort to stay away from people.

Raynox DCR-150 mounted on my Panasonic FZ8.

Friday, June 18, 2010

Barn Funnel Weaver (Tegenaria domestica)

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Generally I have to go out looking for the spiders I photograph, but this one was an exception. As I was doing some laundry, this one ran right over my foot. It was pretty large, about the size of a quarter, and very fast.

These spiders are often found in darker areas, such as flower beds, wood piles, and areas where they can weave a funnel-web. When it is found in homes, it often is found in the basement, in the darker recesses such as closets and corners. It is a nocturnal spider, so generally it is discovered when the lights are turned on and the spider darts for cover. These spiders are not seasonal, but rather, can be found year round, if in a survivable environment.

This species was imported from Europe into the shipping ports when large numbers of settlers immigrated from Europe (starting around the 1600s), and it has steadily spread throughout the United States and Canada.

This spider is not dangerous to people, but is often confused with the Hobo Spider of the same genus, (Tegenaria agrestis), which may or may not be dangerous to humans. Unless you live in the northwest US, it's probably not a Hobo Spider. Look here for the Hobo Spider's natural range. If you are unsure of the exact species, just be mindful of this confusion, and use caution when dealing with the spider.

Raynox DCR-250 mounted on my Panasonic Lumix FZ8.

Thursday, June 17, 2010

Cobweb Spider (Steatoda borealis)

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The spider genus Steatoda, in the family Theridiidae, includes over 120 recognized species, distributed around the world including many cosmopolitan species which are found among human populations worldwide.

Many spiders of the genus Steatoda are often mistaken for widow spiders (Latrodectus), and are known as false black widows; however Steatoda are significantly less harmful to humans. Steatoda are shaped similarly to widow spiders, with round, bulbous abdomens. However, not all Steatoda species resemble widows – many have distinct coloring, and are significantly smaller than Latrodectus specimens. Some species of Steatoda actually will prey on widows, as well as other spiders which are considered hazardous to humans.

Some members of this genus do have bites which are medically significant in humans (such as S. grossa and S. nobilis), however bites by Steatoda species generally do not have any long-lasting effects. The symptoms associated with the bite of several Steatoda species are known in the medical profession as steatodism; and have been described as a less-severe form of latrodectism (the symptoms associated with a widow spider bite).

In common with other members of the Theridiidae family, the Steatoda spiders construct a cobweb, i.e., an irregular tangle of sticky silken fibers. As with other web-weavers, these spiders have very poor eyesight and depend mostly on vibrations reaching them through their webs to orient themselves to prey or warn them of larger animals that could injure or kill them. They are not aggressive, and most injuries to humans are due to defensive bites delivered when a spider gets unintentionally squeezed or pinched somehow. It is possible that some bites may result when a spider mistakes a finger thrust into its web for its normal prey, but ordinarily intrusion by any large creature will cause these spiders to flee.

Raynox DCR-150 and Raynox DCR-250, stacked and mounted on my Panasonic Lumix FZ8.

Friday, June 11, 2010

Male Jumping Spider (Naphrys pulex)

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This is a male Naphrys pulex jumping spider. This spider comes from a tribe named Euophryini, which is spread out all over the world. North America has four described species. In fact its genus name "Naphrys" is actually a contraction for "North American Euophrys".

This is the most widely-distributed Naphrys in eastern North America, found from the East Coast to wooded areas in the tall grass prairies west of the Mississippi River. N. pulex can be very common in mesic hardwood forests, at or near the ground in leaf litter, on rocky outcrops, on bark, or on buildings.

Raynox DCR-150 and Raynox DCR-250, stacked and mounted on my Panasonic Lumix FZ8.