Sunday, September 8, 2024

Spider Sunday: Red Velvet Jumper

Whenever I discover a species new to me, I am compelled to illuminate the known biology of the organism for anyone who will listen, or read. This happened recently, when I encountered a little jumping spider on a sidewalk during a late afternoon walk here in Leavenworth, Kansas, USA, on August 20.

I managed to capture the creature in a plastic vial, to take home for closer observation. At the time, I anticipated that it would be an immature male in the genus Phidippus, as they are common, especially along this pathway through lawn and wannabe prairie that parallels a major street on the north end of town.

I am prone to neglecting or procrastinating in taking photos of captive specimens, so it was August 25th before I finally sat down for a spider photo shoot in the white casserole dish we have dedicated as a “studio” for insects and arachnids. I was fortunate the spider was still alive, albeit perhaps a little more slender than when I first found it.

Throughout the process of capture and photography, the spider was surprisingly slow, which is not at all like most of the fast, bouncy jumpers that I am familiar with. Viewing my photos, it became apparent that whatever this spider was, it was a mature male (fully formed terminal segment on each pedipalp); and it lacked the iridescent chelicerae (jaws) of most Phidippus species.

Puzzled, I uploaded some of the photos to my Facebook page in hopes that some of my friends who are spider experts might be able to point me in the proper direction. It was after posting that I tried looking in some of my books to see if there was anything remotely similar to my specimen. The family Salticidae is highly diverse, and not every book about spiders will include every genus, let alone species. This time I got lucky.

I soon received replies to my social media post, the first of which was from Sarah Rose, author of Spiders of North America from Princeton University Press. That field guide does not include the species she suggested: Ghelna canadensis, but I reached the same conclusion in perusing Common Spiders of North America by Richard A. Bradley. Ian Wright also suggested the genus in his comment on the Facebook post, and Alicia Lips and Dani Marie agreed. Alicia included images of a female of the species that she found on her front porch in June of this year.

Ok, more about the actual spider. The community science platform iNaturalist gives a common name of Three-lined Ground Jumping Spider for Ghelna canadensis. Somewhere I recall reading the name “Red Velvet Jumper,” but that could apply to many other species, even though it is appropriate to the color and texture of this one. Most sources offer no common name. Mature males measure 4-5 millimeters in body length, females 4.6-6.4 mm. Females are darker, gray or brownish, with indistinct markings.

This is a ground-dwelling species, unusual compared to the arboreal species in its cohort, the subtribe Dendryphantina. It occurs over much of the eastern United States, except for the southernmost tier. Data points on iNaturalist have it as far west as Minnesota in the north, and near Dallas, Texas in the south. The "Checklist of Kansas Jumping Spiders" mentions records in Douglas and Jefferson counties, but not Leavenworth. Older references may use the former name, Metaphidippus canadensis. There are also three other species in the genus Ghelna, at least one of which, G. barrowsi, also occurs in my area.

After I finished the photo session, I provided the spider with some water from the tip of a soaked cotton swab. He was thirsty! Then I took him back to where I found him, releasing him well off the sidewalk this time.

Sources: Bradley, Richard A. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.
Guarisco, Hank, Bruce Ctuler, and Kenneth E. Kinman. 2001. “Checklist of Kansas Jumping Spiders,” The Kansas School Naturalist 47(1): 1-13.
World Spider Catalog
GBIF
Bugguide

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