My Next Book

I must admit that I have had a hard time keeping this news under wraps, but now that the paperwork is complete I can officially announce that I will be authoring the Princeton Field Guide to Spiders (official title to be decided later). This will represent my first true solo effort, and with that comes a great deal of responsibility.

It is not lost on me that this may appear to be a redundant work in light of recent popular works on North American spiders. I intend for a fundamentally different publication, though. This will be a true field guide, one that is more portable than either a “manual” or other reference book. Emphasis will be on what can be observed in the field without killing a specimen (though confining one to a vial would allow for closer observation). The appearance of webs, burrows, retreats, and egg sacs, as well as the arachnid itself, will be included. Habitat, geographic range, and behaviors will also be highlighted.

My intuition and experience suggest that what a general audience most wants to know is whether any given spider poses a dangerously venomous threat to themselves, their family, pets, or co-workers. Few references of recent vintage have understood this, and so the resulting books have been overwhelming and of little relevance to what is mostly an urban and suburban audience. These books have also been pricey. Princeton understands that a product of this nature needs to be reasonably affordable.

The other side of the ledger means, naturally, that budgets for the author, and compensation for image usage, is a little less than perfect. Ideally, I would like to come in under budget, and before the April 1, 2016 deadline for delivery of the manuscript and graphics. Some of you will hear from me during this process, as I value your knowledge of arachnids, and/or admire your digital photographic skills.

There is no question that many, if not most, spiders can be reliably identified to species (sometimes even genus) only by examination of minute physical characters, including male and female genitalia. This book will freely admit as much, but the overall intent is for a novice to be able to at least tell what family a given specimen belongs to. We will include a “similar spiders” paragraph for each entry to help users compare to other potential candidates.

I can guarantee that my number one priority is accuracy. I have the utmost respect for arachnologists, especially those who have made an effort to share their expertise with the public; and involving citizen scientists in an effort to broaden our overall knowledge of spider diversity and distribution.

At the core, however, is the fact that I am a professional writer, and that is why the people at Princeton University Press selected me for this project. I appreciate an understanding of my role as a communicator, and forgiveness for whatever I may lack in academic and scientific credentials. The “acknowledgements” page is blank. I look forward to adding your name. Thank you.

Ground Spiders, Sergiolus

Few spiders are as colorful as those in the genus Sergiolus. Why they are so boldly marked is something of a mystery, though there is suspicion that they may be mimicking velvet ants, wingless wasps in the family Mutillidae that pack a potent sting. Sixteen species of Sergiolus are known north of Mexico.

Sergiolus sp. male from Indiana

These nomadic arachnids are very agile, at least when fleeing potential danger, and they often prowl through leaf litter, so you may only get a glimpse of one. Be patient, though, and it is likely to reappear. They are also good climbers, so don’t be surprised to find them on foliage, or walls, too.

Sergiolus are medium-sized members of the family Gnaphosidae, females ranging from 6-10 millimeters in body length, males 5.5 to 7 millimeters. They are mostly diurnal (day-active), so are even more conspicuous than the average spider. The obvious, cylindrical spinnerets at the tip of the abdomen are characteristic of all Gnaphosidae, but helps distinguish Sergiolus from colorful spiders in other families. There are other ornate gnaphosids, such as Callilepis, and separating the different genera hinges on subtle distinctions in the genitalia (epigynum of females, pedipalps of males).

Male Sergiolus sp. from Colorado

Since there are several species, I am reluctant to assign specific names to the images shown here. One of the more abundant species found from the Nebraska and Oklahoma eastward is S. capulatus, sometimes known as the Variegated Spider. It bears an uncanny resemblance to velvet ants in the genus Timulla, which frequent similar habitats: sun-dappled patches on the floor of deciduous forests. The spider is also found in gardens, meadows, even lawns.

Female Timulla sp. velvet ant

One common western species is S. montanus.

While Sergiolus does not spin webs to snare prey, they do construct retreats in which to molt, guard an egg sac in the case of females, and perhaps to overwinter. They probably live over a year, as adults can be found in almost any season. Obviously, they are most active during the warmer months.

Look for these and other spiders, as well as insects, in sunlit spots in wooded areas. You will be surprised at what shows up if you simply sit and watch. Sergiolus can also be found under stones and other objects in reasonably dry situations.

Male Sergiolus capulatus? from Indiana

You can keep gnaphosids in captivity with relative ease. Almost any container will do. Provide them with water, as they do not obtain water from prey. I furnish a small wad of cotton soaked in water at least once per week. A small insect can be fed to a spider every other week or so. Spiders are built to withstand surprisingly long periods without food. Remove the prey insect if it has not been consumed within two days. Spiders preparing to molt will not feed and are therefore vulnerable themselves to predation.

Note: Several members of the genus Sergiolus were once placed in the genus Poecilochroa, and older references treat them as such.

Sergiolus montanus? from Colorado

Sources: Bradley, Richard L. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.
Kaston, B.J. 1978. How to Know the Spiders (Third Edition). Dubuque, IA: Wm. C. Brown Company Publishers. 272 pp.
Ubick, D., P. Paquin, P.E. Cushing, and V. Roth (eds). 2003. Spiders of North America: an identification manual. American Arachnological Society. 377 pp.

Life in a Paper Palace

Back in the 1980s I began my writing career as a volunteer with the Audubon Society of Portland (Oregon). A group of us produced an award-winning publication called The Urban Naturalist. I thought it might be interesting to visit some of those old articles, like this one in the spring, 1987 issue.

It is a battle royal. Queen versus queen, locked in deadly combat with gnashing jaws and jabbing, venomous stingers. A scene from a science fiction soap opera? Alexis versus Crystal? No. At stake is a kingdom of social wasps and the beginning of an annual dynasty.

While most wasps are solitary, the yellowjackets, hornets, and paper wasps are colonial. No true hornets occur in Oregon, but six species of yellowjackets thrive in the Portland area. All belong to the family Vespidae. Three types of adult wasps are present in a mature colony: one reproductive female or queen, many subordinate females called workers, and males or drones. Each princess and prince begins life as an egg, laid in a single, hexagonal paper cell. The egg hatches into a hungry, white larva. Workers feed the grub protein in the form of chewed-up insects or pieces of carrion. The larva grows rapidly, eventually filling its confining cell. Soon, the larva weaves a silken dome over its cell and transforms into a pupa, the resting stage in which its organs are miraculously rearranged into those of an adult wasp. The full-fledged insect then chews off the cap on its cell and emerges.

The entire colony goes through a similar life cycle, beginning in early spring. Not every nest has a violent genesis, but real estate is hard to find and competition is keen. If fate leads a queen to a site already occupied by a nest, she may engage the resident queen in a duel to the death.

Once established, the royal family can grow and prosper through the summer, wrapped inside an architectural masterpiece. The marvelous combs of cells, where the offspring develop, are made wholly of wood fibers, chewed into a papery pulp and mixed with saliva. The combs are stacked, connected by sturdy paper pillars. A multi-layered paper envelope encloses the combs to insulate and complete the durable castle.

The workers expand and repair the elaborate structure, and also defend themselves and nestmates, using their needle-like stingers liberally. Some species can even spray their venom! Only the females possess a stinger which is evolved from the ovipositor, an egg-laying organ. If a battle between queens leaves a young colony orphaned, workers can even produce progeny themselves. Normally, the presence of the matriarch suppresses the reproductive potential of the workers. In her absence, they may lay unfertilized eggs which give rise to males!

The population of a typical colony peaks at a few hundred to several thousand royal subjects when new queens and males mature in the late summer and early fall. They are not accorded the pomp and circumstance granted a royal wedding, but the brief nuptial flights serve their purpose of procreation. Afterwards, the males soon perish.

Male Western Yellowjacket

With the departure of the queens, including the founding mother, the empire begins to crumble. The workers, normally passive, become highly agitated, attacking other creatures without provocation. They may cannibalize the larval wasps remaining in the nest, or simply throw them out.

The kingdom they created with such care, they now seem to destroy with ruthless determination, reminiscent of the deterioration of the Roman empire. For yellowjackets, though, there is a resurrection. After mating, the queens seek appropriate places to spend the winter in hibernation. Most often they hide under bark on stumps and logs, curling their legs and wings beneath them. They awake the following spring to initiate their own colonies.

Be on the lookout for yellowjacket nests overhead and underfoot. The baldfaced “hornet,” Dolichovespula maculata, builds its enormous nests among blackberry canes, low in trees, and shrubbery. Some of these structures are as big as basketballs! Thankfully, the occupants are gentle in nature. Most importantly, these large black and white wasps kill great numbers of flies to feed the larvae in the nest. Sometimes, they prey on other yellowjackets, too.

D. arenaria also builds above ground, often suspending its aerial palaces from human dwellings. The nests, and the wasps themselves, are usually small. These are yellowjackets in the truest sense, colored in alternating bands of black and yellow. They, too, prey on other insects to feed their younger siblings.

By far the most abundant and pesky species is the Western Yellowjacket, Vespula pensylvanica. Large colonies of this wasp live in subterranean nests, built in abandoned rodent burrows, rock walls, and similar cavities. What makes them a nuisance is their habit of scavenging for foodstuffs at picnics, in garbage cans, and other urban situations.. They are predators, too, sometimes killing honeybees to feed on the nectar stored in a bee’s gut. They also will swarm over ripe fruit to feed on the juices, and sip the honeydew secreted by aphids and scale insects.

The Common Yellowjacket, V. vulgaris [Edit: now V. alascensis], is very similar to the Western Yellowjacket in size, color, and habits. It, too, often feeds on carrion and human foodstuffs and becomes a pest.

Prairie Yellowjacket queen (center) with "xanthic" (yellow) and "melanic" (black) workers

V. consobrina, the Blackjacket, resembles a smaller version of the Baldfaced Hornet, being black with sparse white lines. These scarce insects live in small colonies underground and are strictly predatory.

The Prairie Yellowjacket, V. atropilosa, is also an uncommon predator.

Yet another species will likely invade Portland this year. The German Yellowjacket, V. germanica, was originally introduced to the eastern U.S. from Europe. Besides being slightly more aggressive than native species, it has a tendency to nest in houses, between the walls! Isolated colonies have been discovered in California and western Washington, especially along the I-5 corridor. Traffic to Expo ’86 is probably responsible, at least in part, for ferrying this unwelcome immigrant to the Northwest.

Should it be necessary to remove a nest, one can do so with constructive consequences. At least one lady, Betty Pope of Rivergrove, Oregon, will rid you of problem colonies by freezing their female tenants. Their bodies can then be processed into extracts used in the treatment of stings in hypersensitive victims.

On the whole, yellowjackets are beneficial organisms. They dispose of large numbers of pest insects, and also help pollinate flowers. Studying their social behavior may shed some light on human relationships. We may learn that their mysterious population booms and busts are a metaphor for man, a disturbing thought tempered only by the reminder that yellowjackets have learned to cope successfully in an ever-changing world.

I see I had a flair for the dramatic back then. What else has changed? Entomologists were not as easily accessible back then, before personal computers and the internet. I had to use a typewriter and the telephone, and the library.

Comb-tailed Spiders

Chances are you have never seen one of the “comb-tailed spiders,” also known as “dwarf sheet spiders,” in the family Hahniidae. Me, neither, until I started sorting pitfall trap samples at the University of Massachusetts, Amherst, for six months in 2009. Maybe you have never even heard of them before. Forgive yourself, these spiders are, while common, very seldom encountered.

Neoantistea radula male

The overwhelming majority of haniids are under four millimeters in body length….as adults. A few in the subfamily Crypheocinae can reach nearly eight millimeters. So, they are easily overlooked anyway. The images shown here are of preserved specimens under the magnification of a binocular dissecting microscope. Considering their cryptic habits, it is no wonder these escape attention.

Members of the subfamily Hahniinae, save for the genus Neoantistea, don’t even build webs (here in North America at least). The webs of Neoantistea are very thin, sheet-like, and small. They are only visible when heavily laden with dew. They are frequently stretched across the footprints of mammals, and other small depressions in the soil. The spider sequesters itself amid mosses or soil particles at the edge of the web, traveling on the underside of the web to secure prey.

Spinnerets of Hahnia sp.

The most conspicuous feature of hahniids in the subfamily Hahniinae is the arrangement of their spinnerets. All six are aligned in a single row across the back of the abdomen, presumably resembling the teeth of a comb (hence “comb-tailed spiders”). Members of the subfamily Cryphoecinae have a more “normal” arrangement, the spinnerets in two, staggered rows.

Identification of the different genera of hahniids hinges on such characters as the placement of the tracheal spiracle on the underside of the abdomen, relative size of the anterior median eyes, length of segments on the lateral spinnerets, and shape of spurs on the palps of mature male specimens. That’s just for Hahniinae. Cryphoecinae genera are distinguished mostly by features of the male and female genitalia, and dentition of the cheliceral fang furrow (groove in the jaw that receives the folded fang).

Male Antistea sp., underside of male palp showing curved spur on tibial segment

Don’t let the complexity of taxonomy discourage you from looking for these spiders and appreciating their subtle beauty. The genera Neoantistea and Hahnia, with 11 and 7 species respectively, occur throughout most of North America. Antistea brunnea ranges in British Columbia, southeast Canada, and the northeast U.S. Most of the Chryphoecinae are restricted to North America west of the Rocky Mountains, and principally in Canada and northern states, or at least in chronically rainy forest habitats.

Cryphoeca montana

Cryphoeca Montana is a nocturnal spider that has been collected from under bark on dead trees, in leaf litter, moss, and under stones.

The family Hahniidae was once lumped within the family Agelenidae, the funnel-web weavers, at least as recently as 1957, but is now recognized as a stand-alone family.

Sources: Bradley, Richard A. 2013. Common Spiders of North America. Berkeley: University of California Press. 271 pp.
Levi, Herbert W. and Lorna R. 1968. Spiders and their kin. New York: Golden Press. 160 pp.
Ubick, D., P. Paquin, P.E. Cushing, and V. Roth (eds). 2005. Spiders of North America: an identification manual. American Arachnological Society. 377 pp.