Thursday, January 25, 2018

Argiope Trifasciata Spider--Final Bug Spotting of 2017

The spider that I spotted in the morning of December 31, 2017 is in the same spider family and genus as argiope aurantia spider, which I wrote about in "Argiope Aurantia Spider--Part 1, Friday 13th Visitor" and "Argiope Aurantia Spider--Part 2, Post-Friday 13th Observations". The pixstrip images show the palm plant that this article’s spider was in, a peer into the plant, and larger views of the spider and inside of the plant. Click for a really close look of the spider and its spinnerets.

In my excitement over the spider’s striking looks facing me, I overlooked going around the palm plant for photographing or recording the spider's opposite side. In my quest for finding the spider's ID, I spotted various images that matched my best picture, which turned out to be the ventral view of an argiope trifasciata spider. Fortunately, I found some websites that show both ventral AND dorsal views. What a contrast!

In InsectIdentification’s “North American Spiders List”, I picked options at the bugfinder section at the bottom for general bug characteristics. The hits helped narrow down candidate bugs of various creepy crawly types.

I finally found the banded garden spider to be my model spider, but it was a roundabout way of finding the prospect. A helpful site was dPestSupply’s information section and picture for “Banded Garden Spider” (argiope trifasciata). (Coincidentally, just below the banded spider section was information and picture of a black-and-yellow garden spider (argiope aurantia), the one I wrote about in October.)

I found my way to InsectIdentification’s “Banded Garden Spider” page. Click the fourth and fifth thumbnails for viewing fill-the-screen closeups. The latter image very closely resembles my closeup near the top of this article.

As I dug deeper into the spider’s information, I found more corroborating information about the dorsal and ventral views.

BugwoodWiki’s “Banded Garden Spider” website provides basic information and images.
The banded garden spider (Figure 1 and 2) is a large species, with a generally ovoid form and bright markings. Mature females may be 13-14.5 mm when fully extended and the carapace of the body typically between 5-6.5 mm in length.

The banded argiope is an orbweaver spider that produces its large concentrically patterned web in areas of tall grass and shrubby vegetation. The web is sticky and strong, capable of holding fairly large and active insects such as wasps and grasshoppers.

Mating occurs in the latter half of the summer and females produce egg sacs, which have a general shape of a kettle drum. Freezing temperatures kill off all remaining spiders at the end of the season and they have a one year life cycle.
Fletcher Wildlife Garden (FWG) gallery at "Orb Weaver spiders (Araneidae)" shows a gallery of spiders in the family of orb weavers, including the argiope trifasciata spider (this article) and previous month's article about argiope aurantia spider.

View "Banded argiope (Argiope trifasciata), top side" (dorsal) and "Banded argiope (Argiope trifasciata), underside" (ventral). Another ventral view image shows an oval outline and arrow that identify the spinnerets.

A YouTube video "Argiope trifasciata (Banded Garden Spider) - catching a grasshopper" shows the spider in action, rotating itself several times, displaying its dorsal and ventral sides. Note the dorsal side's horizontal bands (invoking thoughts of Jupiter's cloud bands), and the ventral side's two prominent vertical bands with the red spinneret section as the spider maneuvers, wrapping its prey for later consumption.

Curious about the argiope garden spider for similarities and differences? Visit Bugguide's "Genus Argiope" taxonomy page. Also click Info and Images tabs.

2 comments:

Woody Lemcke said...

Thanks for another great arachnid blog and the identification link. I've always been fascinated by their beauty and intelligence.

whilldtkwriter said...

YW! Will be interesting to see if 2018 brings more spiders to my attention. Had never seen argiope aurantia or trifaciata spiders in my life until 2017.