I recently received an e-mail from a resident that went as follows: I have a humongous spider in my backyard in Galveston. It has constructed a huge web which is anchored between a palm tree and a wood fence. Do you know what kind of spider it is? It is big and scary looking!
The above inquiry was sent to me by e-mail and contained not one but two very high-quality photos. Case solved: The photo was that of a female Banana Spider (Nephila clavipes), one of the largest species that occur in our area. The Banana Spider is a brightly colored species of the orb-web spider family.
Nephila comes from Ancient Greek, meaning “fond of spinning.” Most people call them Banana or Golden Silk spiders but other common names are Calico Spider, Giant Wood Spider, Golden Silk Orb Weaver and Writing Spiders. The ‘golden’ refers to the color of the silk, not the color of the spider, for the web of a mature female has yellow threads which look like rich gold in the sunshine.
The Banana Spider occurs in warm regions, from North Carolina and across the Gulf States through Central America, as far south as Argentina, and in the West Indies and extensively throughout Puerto Rico. Banana Spiders like high humidity and relatively open space. They inhabit forest areas along trails and clearing edges including city and county parks.
Banana Spider females are about 3 inches long (including legs) and their color pattern consists of a silvery carapace (outer body wall) with yellow spots on a muted orange to tan cylindrical body. Her long legs are banded brown and orange with feathery tufts or gaiters on the lower segment, making this spider one of the most easily recognized.
The slender males, on the other hand, are a rather inconspicuous dark brown averaging less than a ½ inch in length and would often go unnoticed if not for the fact that they are often found in the webs of females.
The striking difference between the sexes is known as sexual dimorphism. Sexual dimorphism is when the male and female of the same spider species have physical characteristics so different that they appear not to be the same species. Sexual dimorphism is most obvious when the spiders are mature.
The strong web of the Banana Siders is complex. It is a fine-meshed orb suspended in a maze of non-sticky “barrier webs.” They make big webs, about 3 feet wide, spun in a place best-suited to take advantage of the flight paths of other insects.
The banana spider preys on a wide variety of small to medium sized flying insects, which include mosquitoes, grasshoppers, stinkbugs, leaf-footed bugs, bees, flies, small moths and wasps. Banana spiders have even been seen feeding on beetles and dragonflies.
Because of its size, people sometimes assume that the banana spider is dangerous to people. In reality, it is a shy spider (as nearly all spiders are). Just know this species is considered medically harmless to humans.
There is little danger to a healthy adult from an encounter with the banana spider. It will only bite if held or pinched and the bite itself will produce a localized pain with a slight redness, which quickly goes away.
Yes, it may require time for most humans to take a liking to spiders—or at least to reduce their level of disgust or fear. However, if you ever have an occasion to witness some of their beneficial works—especially when you come across one of their large webs filled with the carcasses of Texas-sized mosquitoes and other small flyers that bite—you’re likely to develop a new found admiration and appreciation of the Banana Spider!
Upcoming Programs
WHAT: T-bud Grafting of Citrus & Fruit Trees
WHEN: 9:00 – 11:00 a.m. on Saturday, September 21
WHO: Galveston County Master Gardener Nancy Langston-Noh will present a hands-on workshop on T-bud grafting. This method is used on smaller peach, plum, pear, apple and other trees as well as roses. This hands-on workshop is limited to 20 participants; others are welcome to observe. You must pre-register to participate.
WHAT: Turning Dirt into Soil . . . creating an ideal garden
WHEN: 1:00 – 3:00 p.m. on Saturday, September 21
WHO: Galveston County Master Gardener Jim Gilliam will discuss the difference between dirt and soil, soil structure and characteristics, pH, nutrients, sources and strategies for soil amendment, soil testing and cultural practices. He will emphasize how to improve your existing soil.
WHERE: Both programs will be conducted at the Galveston County AgriLife Extension Office located in Carbide Park (4102-B Main Street) in La Marque. Preregister by e-mail (galvcountymgs@gmail.com) or by phone (281-309-5065).
NOTE: Attached also is a file (IMG03973) in JPEG format.
A fully-grown garden spider can be an intimidating sight. Despite their menacing appearance, banana spiders (pictured) help control many types of insect pests including mosquitoes.
PHOTO CREDIT: Margie Jenke
Thanks,
William
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Dr. William Johnson is a horticulturist with the Galveston County Office of Texas A&M AgriLife Extension Service. Visit his Web site at http://aggie-horticulture.tamu.edu/galveston
