Dirk Stevenson
Bam-bam. Ba-bam-bam-bam. A soft rhythmic hammering carries across the turkey oak sandhill. The noise stops briefly, then sounds off again. It’s not the amorous notes of carpenter frogs from a nearby cypress dome or the resonate percussions made by a snag-banging woodpecker. The drumming is the sound of spider scholars clubbing vegetation in pursuit of poorly-known, beautiful spiders.
I am assisting with a jumping spider survey of sandhill/scrub habitats led by arachnologist Dr. G. B. Edwards. The former arachnid curator of the Florida State Collection of Arthropods (Gainesville), Edwards, along with co-author Dr. Wayne Maddison from the University of British Columbia, is currently conducting a taxonomic revision of two jumping spider genera native to the southeastern United States, Maevia and Tutelina. This project will result in the descriptions of several new spider species, including jumpers specific to gopher tortoise habitats.
Edwards arrives in southeastern Georgia in mid-May. He is excited, voluble. Our main quarry is Maevia intermedia, a sandhill species known in Georgia from only a couple of sites. On an enormous chunk of sandhill along the Canoochee River (south of Statesboro, GA), Edwards hands me a “beat-sheet” and demonstrates the finer points of salticid collecting. A beat-sheet is a 40 X 40 inch piece of nylon parachute fabric supported by a plus-shaped, cross-frame of light weight PVC tubing. The salticid surveyor carefully positions the sheet below vegetation likely to hold spiders, beats the vegetation above the sheet, then carefully scans the sheet for specimens.
Edwards wears a fishing shirt, the kind with dozens of pockets – all of his are packed with small plastic transparent vials; a loupe hangs from his neck. Focusing on the brown dead fronds of saw palmetto clumps, within minutes we capture our target. Maevia intermedia is related to the dimorphic jumpers – mature females are tan with mango-colored stripes on the abdomen; the bodies of males are an intense gun metal silver-to-bluish/black, the color of a newly shed indigo snake in the sun. I had been warned by Edwards that Maevia are the cricket frogs of jumping spiders, a spider bounds once, twice and by thrice is well off the sheet and back in the veg…
The next day, after a 6 am power breakfast rinsed down with chunky coffee at the Huddle King, we sojourn to the impressive Tillman Sand Ridge Heritage Preserve. Located along the north side of the Savannah River in Jasper County, South Carolina, the area is well-known to herp enthusiasts and supports the largest tortoise population in the state. Wading knee-deep wiregrass in a dreamy landscape of well-managed longleaf pine sandhill we find M. intermedia (by the dozens) as well as the sandhill/scrub endemic Workman’s jumping spider (Phidippus workmani). Edwards smiles at our success - both are state records.
On Day 4 Edwards trusts me to venture out solo. I decide to hit one of the “Ohoopee dune” sandhills, where clumps of rosemary pepper mountains of white sand. My confidence as a salticid finder rockets – I work my beater-sheet quickly and deftly, and package my captures efficiently. The spiders come fast and furious, and the generic names of many of the jumpers I find roll off my tongue like poetry − Marpissa, Metacyrba, Tutelina, Synemosyna. My favorite? Lusciously brilliant scales of metallic bronze and iridescent green color the dorsum of the sandhill Tutelina. The spider is an absolute stunner. I leave imbued with the deep satisfaction that comes with discovery.
Salticidae is the largest family of spiders − there are ca. 6,000 recognized species of jumping spiders, with ca. 350 species native to North America. Identifying a jumper as a jumper is easy enough – who hasn’t admired that curious countenance − courtesy of those two huge forward-facing eyes. As far as habitus (form), most are short and stout; abundant hairs lend them a pleasantly fuzzy appearance. Renowned for their intelligent behavior, these spiders show a great deal of interest in humans by cocking their cephalothoraces to look at us. Jumpers exhibit complex, learned behavior and have excellent color vision. When hunting (no web here, folks) they stalk then pounce on prey, just like a cat. The fellas engage in elaborate diurnal courtship displays that feature ritualized movements of decorated body parts. In some species, vibratory signals produced via stridulation or percussion are also used to stimulate the ladies. One astute arachnologist observed that the males with the best song and dance win the females.
By Day 5, the waitresses at Huddle King know us by name. Still more turkey oak stems, palmetto fronds and huckleberry shrubs are introduced to the beater-sheet. The by-catch one encounters via beating is riveting and informative – you will bump from their perches a wide breadth of spider diversity (including those macabre ogre-faced spiders), caterpillars, pseudoscorpions, mantis and walking sticks galore, strange hemipterans you haven’t seen before, hatchling anoles, squirrel treefrogs, and once even a rough greensnake.
Edwards schools me on a wonderful genus of jumpers which he has studied in detail. Phidippus are the big furry dogs of the salticid world, and our sandhill fauna includes some spectacular species. The green-fanged regal jumper (P. regius), mostly limited to Florida and southern Georgia, at close to an inch long (big females that is) is the largest jumper on the planet. I commonly find this species in the late winter (sometimes close to scorpions and scarlet kingsnakes), under the exfoliating bark of longleaf pine snags, where individuals nestle in cotton-white silken retreats called “nests”. Yes, you will find mention of the regal jumper in papers listing “arthropods that eat vertebrates” (prey includes tiny lizards and hylid frogs)!
In the deep south, the Apache jumper is characteristic of open-canopied sandhill and sand pine scrub communities. Edwards published an article describing how individuals of this bright red-and-black spider mimic females of the large velvet ant, Dasymutilla occidentalis. Complementing their similarity in color, these jumpers, when on the ground, adopt the peculiar, jerky gait typical of this potent-stinging mutillid wasp.
On Day 6 we captured four species (of 3 different genera) of jumping spiders that mimic ants, including the first state records (for Georgia) for Synemosyna petrunkevitchi and Peckhamia scorpionia! These bizarre little beasts will have you shaking your head in amazement. Characteristics of ant-mimic jumpers include a groove/depression in the cephalothorax (making it look like the head and thorax of an ant) and especially elongate, constricted abdomens (just like ants in the genus Pseudomyrmex). Depending on the genus, some species wave their 1st or 2nd pair of legs as they walk, mimicking ant antennae.
I sit out Day 7. During the late afternoon I visit Edwards at his motel room, located in the same medium-sized, south Georgia town where I reside. I had stopped by to deliver a fat box of pet shop pinhead crickets, supper for his hungry eight-legged charges. He got the weekly rate, and the accommodations here are indeed modest (but it’s located within walking distance of the H King). The air conditioner alternately coughs and hiccups as I examine some of the many dozens of spiders, all packaged individually in carefully labeled vials, that we have collected. The vials cover the surface of every piece of furniture, including the bathroom vanity, and are also strewn about on the bed. Southern Georgia is an under-studied region, arachnologically-speaking, and ultimately the specimens we collected will be deposited in one of the best spider collections in the country (the Florida State Collection of Arthropods).
When it comes to spider taxonomy, key characters used in separating/describing species include features of the pedipalps, chelicerae, and genitalia, as well as color/pattern. Mature adults are needed for such efforts. Most jumping spiders are univoltine (i.e., 1 generation per year) and have 5-11 instars. A number of spiders we collected were penultimate, or antepenultimate, specimens (meaning with 1-2 additional molts, respectively, they would become adults). Edwards would have a lot more work to do raising the immature specimens he had collected, but he considers it worthwhile to have additional adult specimens of such rare and unusual species for study.
A wealth of information and many hundreds of awesome photographs of the jumping spider fauna of the southeastern U.S. may be found on Giff Beaton’s webpage: Jumping Spiders: North America (giffbeaton.com)