Spider Sunday: Scarlet Sheetweb Weaver

Exploring our modest property the other day I had the good fortune of encountering a small but striking spider on the exterior of our garage. It was a male Florinda coccinea, known as the Scarlet Sheetweb Weaver or Black-tailed Red Sheetweaver. At only 3-3.5 millimeters in body length, it is usually difficult to spot despite its bright red color, with black accents.

The males are generally more conspicuous than the females if only because they must travel to find one or more mates. They are shockingly agile for a species that is normally most at home in a silken snare. They appear acutely aware of motion, at least a large creature like myself, and I almost missed out on getting an image at all, as the spider dropped suddenly into foliage below.

Last fall, on October 8, 2021, my wife and I were on a morning neighborhood walk. A large group of bright orange mushrooms growing in a strip of lawn in a park caught our attention, which in turn led us to spot several small, dew-covered sheet webs in the grass. It is no wonder these spiders are so difficult to find. The silk of their webs is so fine that the sheets are nearly invisible unless coated in water droplets. We found both males and females in the webs, which makes me think this species may have more than one generation each year.

Curiously, most scientific references consider Florinda coccinea to be a mostly southeastern species, though it ranges north to at least Maryland and southern New Jersey, and west to Missouri and the eastern edge of Kansas. It might be expanding its range northward and westward, or simply be so inconspicuous to avoid detection by the few people out there seeking spiders. We collectively have much to learn about the actual geographic distributions of most arachnid species.

Florinda coccinea, a member of the family Linyphiidae, is identified by the black tubercle on the rear of the abdomen, a feature not seen in similarly-colored spiders. I also learned that they are exceptionally adept at feigning death when they perceive a threat. I was convinced my poor male was deceased or nearly so, but offered it a little water with the tip of an artist's paintbrush, and left the spider and the brush in a casserole dish overnight. The next morning the spider was much more lively, and after a quick photo session it was released outdoors.

Sources: Howell, W. Mike and Ronald L. Jenkins. 2004. Spiders of the Eastern United States: A Photographic Guide. Boston: Pearson Education. 363 pp.
Marshall, Sam, and G.B. Edwards. 2002.Florida's Fabulous Spiders. Tampa: World Publications. 65 pp.
Gaddy, L.L. 2009. Spiders of the Carolinas. Duluth, Minnesota: Kollath+Stensaas Publishing. 208 pp.
Kaston, B.J. 1972. How to Know the Spiders (Third Edition). Dubuque, Iowa: Wm. C. Brown Company Publishers. 272 pp.
Bradley, Richard A. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.

Wasp Wednesday: Southern Yellowjacket

Upon returning home last Thursday, I noticed the silhouette of what I thought was a paper wasp on the inside of one of the garage windows. It turned out to be something more exciting than that. Here in eastern Kansas, it is the time when female social wasps of all sorts are founding new colonies, or at least seeking a place to set up housekeeping. This individual is no exception, but she also has a devious alternative strategy she can use.

I gently captured the wasp in a plastic vial. In better light she was instantly recognizable as a queen of the Southern Yellowjacket, Vespula squamosa. This species is not quite as common as other species in eastern North America, so it was nice to have a chance to see one up close and finally get some respectable images of those muted ochre and yellow colors. As beautiful as these wasps are, their biology is even more fascinating and somewhat frightening.

Southern Yellowjacket is sometimes an "inquiline," a facultative social parasite of other yellowjacket species, namely the Eastern Yellowjacket, Vespula maculifrons, but also the Widow Yellowjacket, Vespula vidua. That is to say that while Southern Yellowjacket can exist like any normal, free-living yellowjacket species with a queen, worker caste, and males and new queens at the end of the colony life cycle, it can also hijack the colony of another species for its own benefit of free labor. Conversely, an obligate social parasite cannot exist on its own. It must successfully usurp a host nest. Obligate social parasites have no worker caste, only queens and males (in the case of yellowjackets).

Southern Yellowjacket worker from Ohio, USA

Competition for optimal, concealed nesting sites can be keen, so social parasitism may have evolved as one way to solve this problem. Eastern Yellowjackets typically nest in abandoned rodent burrows and similar cavities, but they can also nest in wall voids of human structures. It is telling that colonies of this species in disturbed habitats and urban and suburban locations appear to be the most vulnerable to being taken over by Southern Yellowjacket.

The Southern queen typically invades an embryonic nest of its host, dominating, evicting, or killing the resident queen. There may or may not be any host workers at the outset, but eventually the nest is converted entirely to Southern Yellowjacket workers. Evidence of the host remains in the differing architecture of the nest. Southern Yellowjacket is a significantly larger insect than Eastern Yellowjacket, so the cells in the paper combs of the nest differ accordingly.

Southern Yellowjacket male from Tennessee, USA

A mature nest of Southern Yellowjacket, persisting into late autumn, may contain an average of 5,000 cells. That is a lot of wasps! Southern Yellowjacket is not inherently more aggressive than most other yellowjacket species in defense of their nest, but more workers means a greater response to disturbance. You may want to inspect your yard carefully before using any powered tools that could cause vibrations and spark a yellowjacket offensive.

Southern Yellowjacket ranges from the Great Lakes to the Atlantic coast south of New England, to Florida, and west to Iowa, Kansas, and most of eastern Texas. It also occurs in southern Mexico and Guatemala, making it quite literally our southernmost species of yellowjacket.

Sources: Akre, R.D., A. Greene, J.F. MacDonald, P.J. Landolt, and H.G. Davis. 1980. Yellowjackets of America North of Mexico. U.S. Department of Agriculture, Agricultural Handbook No. 552, 102 pp.
Kratzer, Chris Alice. 2022. The Social Wasps of North America. Frenchtown, New Jersey: Owlfly Publishing, LLC. 417 pp.

Getting the Messages Out There

The greatest challenge for an author may come after the book is published, when you have to take an active part in marketing the finished product. Modesty must be set aside, and nervousness overcome, in making media appearances. This is when imposter syndrome attempts to assert itself, but then you remember all the research you did, and that science is changing all the time. Any anxiety is a small price to pay for the opportunity to broadcast positive messages about the natural world, and inspire the changes we need to make for enhanced biodiversity.

I was recently invited to be a guest on a major media platform, and a wonderful science podcast. Both were rewarding and humbling experiences.

AccuWeather, Inc. is a familiar media company that furnishes weather forecasting services globally, including watches and warnings for severe weather. They supplement this information with other scientific topics, and I was asked to talk about the relationship between insects and humanity, for about seven minutes:

Click here for the video

I’d like to thank host Adam Del Rosso for making me feel comfortable and explaining everything that would happen before, during, and after we made the recording. I would also like to compliment the AccuWeather graphics department for inserting some lovely video footage to complement our conversation.

Earlier in the month I interviewed with Michael Hawk, host of Nature’s Archive podcast, for episode #44.

Michael recognizes the complex landscape of environmental issues, and how they are intertwined, so our conversation covered many seemingly disparate topics. If any part of the episode strayed into “stream of consciousness” territory or went off the rails, that was no fault of Michael’s.

I have received much positive feedback for these two appearances, but please be assured I am not simply “saying all the right things” or being politically correct in asserting that the field of entomology needs to be more inclusive and diverse. Talking is easy, action is not. I am doing my best to actively promote the work of scientists and science communicators who are not from conventional demographic categories. I’ll have more to say about that as my behind-the-scenes activities on projects eventually reach the public.

Thank you for your continued investment in this blog, please know you are appreciated.