Gromphadorina portentosa

I found myself with a few spare moments this weekend, so I decided to finally put together a white box and see what I could do with it.  And what better subject for a white box maiden voyage than Gromphadorina portentosa, the Madagascan hissing cockroach.  Grotesquely beautiful, it also presents a challenging subject for flash-based macrophotography because of its hard, shiny exoskeleton that produces strong specular highlights with all but the most highly diffuse of light sources.  It was also the only live subject I had on hand at the moment, other than a few larval noctuids – not nearly as impressive as these behemoths!  There were some early glitches – the enormous size of these insects made for long working distances, with the result that my box was almost too small!  However, placing the subjects at the back of the box allowed the camera lens and flash units to sneak just inside the front drape, and the closer shots went more smoothly.  I’m quite happy with the results – at least as a first attempt, and I think the method shows even more promise for some preserved specimen photographs that I am planning.

The males, of course, have “horns” on the pronotum, but one thing I had never noticed before is the well-developed lip at its anterior edge.  This is certainly an adaptation to the “shoving” matches that males engage in with each other frequently.  This face-on shot shows him for the formidible opponent that he is!

Sexual dimorphism is fairly evident in this species, as least compared to your average cockroach.  Like most insects, females tend to be a little larger, especially when they are gravid as the one below appears to be.  In my colony I note that they also tend to be more uniformly dark in color than the males, although that is not quite so evident with this particular female.

The big difference is, of course, the weakly developed pronotal protuberances.  Females don’t engage in the shoving matches that males do, so there is no need for the heavily armed pronotum.  Nevertheless, small pronotal humps are still found in the adult females.  Note also the lack of a well-developed lip on the anterior edge of the female pronotum.

Photo Details: Canon 100mm macro lens on Canon 50D, ISO 100, 1/200 sec, f/8-11, indirect MT-24EX flash in white box.

Copyright © Ted C. MacRae 2010

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Up the Glacial Staircase

During last year’s visit to Lake Tahoe, we attempted to hike Eagle Falls Trail, one of Lake Tahoe’s most scenic and popular trails.  Beginning at the Hwy 89 trailhead above Emerald Bay, this trail climbs a dramatic ‘glacial staircase’ with steep, narrow gorges connecting a series of deep lakes and meadows.  Each of these lakes, and indeed Emerald Bay itself, was formed as a result of glaciers that carved Lake Tahoe’s granite shores until as recently as 10,000 years ago – leaving behind scars of incomparable beauty.  Eagle Lake perches atop one of these steps – only a short, one-mile hike up the trail but rising nearly 2,000 feet above the trailhead.  Summer hikers have trouble enough dealing with this elevation gain, but winter hikers – as we learned last year –  find it impossible without the assistance of snowshoes.  The first steep section just short of Upper Eagle Falls would prevent any further progress, leaving me with only a teasing view up the gorge and a commitment to try again on our next visit.

There was even more snow this year than last – a good 4-6′ it appeared, but our rented snowshoes made this irrelevant (even desirable), and the four of us began the arduous task of climbing the snow-laden slopes all the way up to Eagle Lake.  It was a family affair, so the pace was dictated by 10-yr old Madison, who got us to Eagle Lake – serenely beautiful and frozen solid – in a leisurely 1 hour 45 minutes.  The hike back down the gorge passed more quickly (almost too quickly) but provided spectacular views of Emerald Bay and Lake Tahoe below. Those of you with an interest in the geological history of Lake Tahoe may refer to my earlier posts, Lake Tahoe, California (Mar 2008) and Born of Glaciers (Mar 2009).  The rest of you may just enjoy these pretty pictures.

View of Upper Eagle Falls - it was here where our hike last year would end.

View back down the gorge from bridge over Upper Eagle Falls.

Looking back down at Emerald Bay from Eagle Falls Trail.

Further up the trail, one looks back upon this spectacular view of Jake's Peak.

Eagle lake lies at 8,500' elevation (frozen lake surface visible through trees left).

Copyright © Ted C. MacRae 2010

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Friday Flower – Ozark Witch Hazel

Spring is beginning its “march” across the nation, and in typical fashion the month started out with the promise of pleasant weather but is throwing a few tantrums before giving way to April. For most folks in the lower Midwest, spring began a week or so ago when daffodils began popping up from nowhere and dotting the suburban and semirural landscapes with their yellow smiles. Forsythia are also set to burst forth, their appearance temporarily put on hold by this latest cold/wet snap, but when they do most people here will be satisfied that spring has finally come. For me, spring comes much earlier, and it’s not planted ornamentals that mark its beginning, but native trees.  Silver maples (Acer saccharinum) and American elms (Ulmus americana) are first, bursting open in the very first warm days of early March.  These are followed by the sugar maples (A. saccharum) and red maples (A. rubrum) that are in full bloom now, which will themselves give way to the redbuds (Cercis canadensis) and serviceberrys (Amelanchier arborea) that will close out the month before flowering dogwood (Cornus florida) dominates the area’s understories in April.

There is one tree in this part of the country, however, that shows its amazing blooms in January and February while winter’s grip is still strong.  Ozark witch hazel (Hamamelis vernalis) is restricted to the Ozark Highlands of Missouri and Arkansas, where it grows along the rocky creeks and streams that dissect this ancient landscape.  I have long wanted to see its striking blooms, but despite my many wintertime hikes throughout the Ozarks, I have never found myself in the right place at the right time – until a few weeks ago when I hiked the Mina Sauk Trail at Taum Sauk Mountain State Park.  I found these plants growing below Mina Sauk Falls and along Taum Sauk Creek below, and even though it was the first weekend of March (and the very first warm day of the season), many of the plants had already passed their peak bloom.  Fortunately, I was able to find these several plants with flowers still in good shape.

There is only one other species in the genus – eastern witch hazel (Hamamelis virginiana).  Although distributed widely across eastern North America, it is restricted in Missouri to these same St. Francois Mountains where I saw H. vernalis.  The two species are very similar by the characteristics of their foliage but can be easily distinguished by floral characters.  Hamamelis virginiana blooms in fall rather than winter, and its flowers, while nearly twice the size, rarely show the amount of red on the inner calyx that is seen in this species.  Hamamelis vernalis flowers are also quite fragrant, having what has been described as a “vanilla” scent.  The photographs here show the rather unusual color range of the flowers of this species, which can vary from orange to deep red to deep yellow.  I suspect that flower color also changes with age, in that petals are initially deep red and later fade to yellow, as in the photo below.  It’s difficult to explain why H . vernalis is restricted to the Ozark Highlands while H. virginiana occurs so broadly, but the Ozarks are a well-known refugium for a number of other plants and animals, especially Ice Age relicts.

Sitting on a rhyolite ledge overlooking Taum Sauk Creek as I ate lunch, I wondered about the pollination biology of a plant that flowers during winter.  It was a warm day – certainly an unusual occurrence during the period in which this plant flowers – and even still it was too early in the season for a lot of insect activity.  I watched one of the nearby plants as I ate to see what insects came to the flowers, and for a time all I saw were a couple of European honey bees.  Clearly, the plant did not evolve in association with this now ubiquitous insect.  I continued watching, and at last I saw a native insect visiting the flowers – a large species of hover fly (family Syrphidae), perhaps something in the genus Helophilus.  After taking a few more photographs (unfortunately, none of the fly), another of the same species visited the plant.  Flies in general are famous for appearing during warm days in winter, and I wonder if the unusually extended bloom period of this species is intended to take advantage of those few, unpredictable days during winter when temperatures are sufficient for flies to become active.

Photo Details: Canon 100mm macro lens on Canon EOS 50D
Photo 1: ISO 100, 1/200 sec, f/11, MT-24EX flash w/ Sto-Fen-Puffer diffusers.
Photo 2: ISO 200, 1/200 sec, f/5.6, ambient light.
Photo 3: ISO 100, 1/60 sec, f/9, flash w/o diffusers.
Photo 4: ISO 200, 1/250 sec, f/5.6, ambient light.

Copyright © Ted C. MacRae 2010

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Pismire Puzzle

I returned home from a much-needed vacation late last night, and even though it was a family trip I have much to share from the past 10 days. However, I must remain coy about where I was for the time being so that I may present this little quiz:

Who am I?

I had planned to post this yesterday, but the best title I could come up with – “Monday Myrmecine Mystery” – was just too similar to a Monday tradition on another blog that we’ve all grown to love.  (Also, I just couldn’t get to it.)  No longer constrained by an M-themed title, I came up with this alternative¹ that I hope will make the 12-year old boy in each of us giggle aloud.

¹ Pismire (from pissemire) is an archaic name of Scandinavian origin for ant. Derived from pisse urine (referring to the smell of formic acid) + mire ant.

What am I doing?

I expect members of the Formicine Guild will jump all over this, so I should probably make this quiz about more than just the name of the ant (which I don’t know, so does that make this an illegal quiz?).  Maybe I should offer double points to non-myrmecologists for a proper ID (but then, I would need the consensus of the myrmecologists – perhaps a conflict of interest?).

Why do I do this?

I could also offer points for correctly guessing what the ant is carrying – which again I wasn’t able to figure out, so I guess points will have to be awarded for the most plausible explanation.  What I do know is the ant carried this carcass while meandering aimlessly over the same patch of ground – occasionally stopping very briefly to dig its jaws into it before resuming its wanderings.  I followed the ant for about 10 minutes, and it never left an area of about 1 square foot – no nest nearby that I could see, no direction to its travels, no apparent purpose to its labors.

This is where I live.

I most definitely know where I was, so firm points are on offer for correctly guessing the answer to that question – either on the basis of the ant ID or the above photograph of its habitat.  Yes, that is snow on the ground – lots of it!

Copyright © Ted C. MacRae 2010

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The Inexorable March of Spring!

Granted, the progress of spring seems to advance in halting baby steps with occasional falls onto its muddy bottom, rather than as a determined forward march, but spring is welcome, no matter how it arrives. When little green tips start poking up and there’s a bit of that “spring smell” in the air, I simply must get out and catch up on the status of Nature — the old-fashioned way (she doesn’t have a Facebook account). Over the last week, I’ve gone forth in search of signs that everything else living is about as tired of winter as I am, and wants to get this spring show on the road! There is already so much happening, I can’t recount it all here — A partial list of unphotographed notables: owls breeding; hawks nesting; woodcocks doing their silly, repetitive and almost invisible (because it’s nearly dark) courtship displays; wood ducks on forest ponds; year-round resident songbirds reestablishing territories; spring peepers, chorus frogs, wood frogs and southern leopard frogs singing, especially in the fishless ponds; winter crane flies and midges swarming in sun flecks in the woods; wild filberts, silver and red maples flowering, etc…

Formica pallidefulva sniffs the spring air


Of course, I look for the first ants out at this time of year, though with the exception of 10 March, when the temperature exceeded 70F, they haven’t been notably active. However, that afternoon I encountered, among others, a worker of Formica pallidefulva poking its head out cautiously to sniff the spring air. This is one of my favorite local ants — largish (5-6mm), abundant, active in daylight even when it’s hot, usually shiny bronzy red to red-brown, usually with a darker gaster (the apparent abdomen of ants) around here, but ranging from a beautiful reddish gold (in the deep South) to almost pure black-coffee brown (New England and southern Canada) across its wide geographic occurrence (Rocky Mountain foothills of Wyoming to New Mexico, all the way east to Québec and Florida). It has the added charm of being the host species to a wide range of social-parasitic and dulotic (“slave-making”) ants both in its own and in another closely related genus, with which it lives in temporary or permanent mixed colonies (as with the Polyergus illustrated in my last post). The image below of these ants bringing home a charred earthworm was taken almost one year ago, as one of Shaw Nature Reserve’s prairie areas was beginning to resprout after a prescribed burn a few weeks earlier. Ants will take their food raw or cooked!

Formica pallidefulva with charred earthworm


Prenolepis imparis alate in the clutches of a gerrid

Another ant I mentioned last time I was with you, Prenolepis imparis, has the distinction of being the only ant in our fauna that has mating flights while there is still a good chance of frost in the forecast for the next few weeks. In this picture of a mating pair at  BugGuide, note the size difference that inspires their name “imparis”, Latin for disparate. Any time after mid-February when it is sunny and not too windy, and the temperature rises above 65F, the winged males and females reared the preceeding fall, fly out to partake of a grand insectan orgy. Typically, they have big flights on the first couple of appropriately warm days, then some smaller ones (i.e., fewer individuals participating) over the next few weeks. The flying males look like gnats, bobbing up and down in drifting swarms, a few feet off the ground over a shrub, near a woodland edge or in a sunny opening. (One of my co-workers got into the midst of a group of such swarms once when we were conducting a prescribed burn in a wooded area, and I recall her commenting she “felt like Pigpen with all the little bugs flying around”!) The much larger, golden-brown females lift slowly off the ground, fly ploddingly (or is it seductively?) through the male swarms, are there mobbed by the tiny fellows, and then glide away and slightly downward, mating in flight with the winner of the males’ tussling. Rather clumsy fliers, the females do not always land in a good spot, as occurred to this hapless one that ended up as a feast for a water strider. Those that survive break off their wings, dig a burrow, seal themselves in, and raise a small brood of workers on food produced in their own bodies (like say, milk in mammals or “cropmilk” in doves and some other birds.)

But lest you to think I only have eyes for ants, I feel indeed fortunate to have encountered a tarantula this week, of the same species as Ted recently posted and I didn’t even have to go to Oklahoma for it. This bedraggled individual was at the mouth of its completely flooded burrow in what is most often a very dry habitat — a dolomite glade. Stunned and muddy at the time, my guess is this creature, belonging to a resilient and ancient lineage, will dry off, clean up, and saunter away as soon as she warms up.

Aphonopelma hentzi in flooded burrow


And speaking of emerging from flooded burrows, how about this handsome fellow, a male three-toed box turtle, his sex revealed by his bright orange and red markings, coming up for a breather? In truth, it was perhaps only just warm enough to make him need air, but not really enough so for him to be up and about, so he just sat there, nearly immobile, looking pretty, notwithstanding mud and leaves glued onto his shell.

Male box turtle emerges


Copyright © James C. Trager 2010

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Clubmoss along the Ozark Trail

It has been a long, hard winter – one of the toughest I can remember during my years here in Missouri in terms of amount and frequency of precipitation and persistent cold temperatures. Tough winters, however, are no deterrent to my favorite wintertime activity – hiking. I’ve mentioned several times the goal of my friend Rich and I to hike all 350 miles of the Ozark Trail.  We’re at ~250 miles now (more than 2/3 done), thanks to the two 10-mile stretches of the Wappapello Section that we did on the days after Thanksgiving and New Year’s. 

Hiking these trails is an opportunity to imagine the Ozark Highlands in their wild, pre-settlement state – expansive hardwood forests covering miles and miles of rugged up-and-down terrain.  Of course, try as I might to pretend otherwise, the Ozarks have changed, and evidence of man’s pervasive presence are everywhere.  Some are overt, such as this mass grave of domestic cattle, dumped by their former owner for others to worry about when disease prevented them from realizing their economic potential.  Others are much more subtle, but to the discriminating naturalist they are everywhere – even in the most pristine-looking of areas.  A cedar-choked glade here, it’s rich, tawny, native warm-season grasses pushed the margins and interspaces; a monotonous, stunted black oak forest there, sprigs of herbaceous plants giving a hint of the diverse understory just waiting for a fire to bring back the more open woodland it needs to thrive.  Settlement has brought with it not only direct impacts to the land, but also changes in its ecology and vegetational character.  Once a fire-mediated landscape with shifting mosaics of bald ridges, grassy woodlands, and riparian forests, a century of logging, grazing, and fire suppression have turned much of the Ozark Highlands into homogenous stands of oak with depauperate mid- and understories.

While loss of diversity has been the overwhelming trend in response to settlement, additions to the state’s flora are also being seen.  The Wappapello Section is the southeasternmost of all the Ozark Trail sections, lying almost entirely in Wayne County, and as we traversed the rugged terrain north to Sam A. Baker State Park, we encountered this most unusual of plants – a clubmoss.  Since they are vascular plants, clubmosses are not really moss (which are non-vascular).  Clubmosses are not flowering plants either, nor do they even produce seeds, reproducing instead by spores – just like ferns, horsetails, and other ‘primitive’ (sorry, Alex!) vascular plants.  Practicing botanists include them in a group known as “fern allies”, meaning that they are not ferns (ferns have multiple branching veins in their delicate fronds, while clubmosses have a single vein in their small, scale-like leaves), but they are somewhat like them.

This particular clubmoss belongs to the genus Lycopodium, or ground cedars – the name obviously derived from the resemblance of their foliage to various gymnospermous plants known as cedars (though completely unrelated) but growing very low to the ground. There are three species of Lycopodium in Missouri (Yatskievych 1999), all confined to the Ozark Highlands and all considered species of conservation concern due to their rarity in the state (Missouri Natural Heritage Program 2010).  Two of these species are highly restricted (designated S1 for “critically imperiled”), boreal species occurring only on moist sandstone bluffs in Ste. Genevieve County as Pleistocene relicts – holdovers from a time when glaciers advanced to within about 50 miles to the north and cool, wet conditions prevailed throughout the rest of the state.  The third species, shown here, is Lycopodium digitatum.  Although more widespread in the cool forests of the northeastern U.S. and Canada, it is apparently expanding its range and was first found in Missouri in 1993.  While still considered uncommon (and accordingly designated S2, or “imperiled”), its range has since expanded to a core of several southeastern Missouri Ozark counties that include Carter, Iron, Madison, Reynolds, and Wayne Counties (Doolen and Doolen 2008).  We found this colony at the base of a moist wooded slope amongst an invading stand of Juniperus virginiana (ironically, called “cedars” by local residents).

“Running ground cedar” has been used as a common name for L. digitatum, most likely due to its habit of spreading by rhizomes – or “runners” – along the soil surface.  From a distance, the spore-producing strobili stood out in bright yellow contrast to the dark glossy green foliage that carpeted the ground – itself in stark contrast with the surrounding brown leaf litter.  It is these club-like strobili from which the common name “clubmoss” is derived, and from a distance of 20 m away I knew instantly that this was something unusual and worthy of investigation.  Despite the gray November skies and cool temperatures, the strobili were actively shedding spores – clouds of yellow dust swirling briefly with each knock of the finger before dissapating into the air.

Hundreds of millions of years ago, the Carboniferous earth was covered with vast forests of giant clubmosses – extinct relatives of this species that soared to heights of one hundred feet. These giants eventually gave way to new kinds of plants – first the seed-bearing conifers, and later the flowering angiosperms. The giant clubmosses are gone, but their descendents have survived the vastness of time, represented today by these humble, diminutive forms – extant members of an ancient group hiding in the nooks and crannies of the modern flora. I don’t know whether the recent appearance of L. digitatum in the Ozark Highlands is a result of the anthropogenic changes brought upon the area in recent years, but given its ancient, relictual qualities, it is one change in the flora of Missouri that I do not mind.

REFERENCES:

Doolen, W. and C. Doolen.  2008.  Clubmoss wonders in southeast Missouri.  Perennis, Newsletter of the S.E. Missouri Native Plant Society 1(4):1–2.

Missouri Natural Heritage Program.  2010.  Missouri Species and Communities of Conservation Concern Checklist.  Missouri Department of Conservation, Jefferson City, Missouri, 53 pp.

Yatskievych, G. 1999. Steyermark’s Flora of Missouri, Volume 1. Missouri Department of Conservation, Jefferson City, 991 pp.

Copyright © Ted C. MacRae 2010

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North America’s largest jewel beetle

Euchroma gigantea in Jamaica. Photo © Steve Meyer


In recent weeks I’ve featured a few jewel beetles that I have encountered amongst specimens sent to me for identification (see “Aaack!-maeodera” and “Acmaeodera carlota in northern Arizona“).  While the new distributions and even unknown species that they represent are fascinating from a scientific perspective, their diminutive size (~6 mm in length) probably makes them less than spectacular to the non-specialist.  The family Buprestidae does, however, contain some very large species, including a few that qualify as bona fide giants.  One such species, Euchroma gigantea (Giant Metallic Ceiba Borer Beetle), occurs from Mexico through Central America, the West Indies, and most of South America.  At a maximum of 65mm in length, it is not only North America’s largest jewel beetle, but also the largest jewel beetle in the entire Western Hemisphere.

My colleague Steve Meyer encountered and photographed this individual in Negril, Jamaica.  Although its scientific name translates to “colorful giant”, the beetle in the photo is especially so due to the delicate, waxy bloom covering its elytra. This bloom is secreted by the adult after transforming from the pupa and prior to emerging from its larval host, giving it a bright yellow-green appearance.  After the beetle emerges and becomes active, the bloom is quickly rubbed off and the beetle takes on the shiny, iridescent purple-green color by which it is more familiar.  The presence of bloom on this individual suggests that it had just emerged from the trunk of the kapok tree (Ceiba pentandra) on which it was sitting.  Kapok and other large trees in the family Bombacaceae serve as hosts for larval development for this species (Hespenheide 1983).

Indigenous peoples in Central and South America have long utilized the dazzlingly colored elytra of these beetles to create beautiful natural jewelry and adorn their clothes and textiles.  The species is also eaten in both the larval and adult stages – Tzeltal-Mayans in southern Mexico (Chiapas) roast the adults when available, and the Tukanoans (northwestern Amazon) also eat the larvae (Dufour 1987). I have eaten a few insects in my day, but none as thick and massively juicy as the grub of this species must be. Holometabolous larvae typically contain a rather high percentage of fat (up to 66% dry weight) to meet the demands of pupal development and adult reproduction, and I suspect this makes the larvae quite tasty (especially when roasted). If there is any insect in the world that I really, really, really want to eat – it is the larva of this one!

REFERENCES:

Dufour, D. L.  1987.  Insects as food:  A case study from the northwest Amazon.  American Anthropologist 89(2):383–397.

Hespenheide, H. A.  1983.  Euchroma gigantea (Eucroma, giant metallic ceiba borer), p. 719.  In: D. H. Janzen [ed.], Costa Rican Natural History, University of Chicago Press, Chicago.

Copyright © Ted C. MacRae 2010

Tuesday Tarantula


One of my destinations on my annual fall tiger beetle collecting trip last October was The Glass Mountains in northwestern Oklahoma. Rising from the red Permian beds of the central Great Plains, the Glass Mountains are a series of mesas and buttes capped by thick layers of the sparkling, glass-like crystal selenite. It is still common to see them referred to as the “Gloss” Mountains, the result of a transcription error by a mapmaker back in the late 1800s, and although the soils that comprise the formations are very old (laid down as sedimentary deposits during the Permian Era some 250 million years ago), the landscape itself is relatively young – a result of erosion by glacial outwash from the Rocky Mountains during the past 1 million years.

Of course, I was not here to study crystals or geology, but to look for tiger beetles! It was at this spot that earlier in the year (June) I had discovered a new population of Cylindera celeripes (Swift Tiger Beetle), a rarely-collected flightless species that has declined worrisomely during the past century, and another seldom-collected flightless species, Dromochorus pruinina (Frosted Dromo Tiger Beetle), was also a good find. Neither of these species were my reason for being here in October, however, since by then adults of both have long disappeared. Instead, I was hoping that the large, unidentified larvae that I had seen in their burrows at this site back in June would be out as adults. Their great size suggested two possibilities – Cicindela obsoleta (Large Grassland Tiger Beetle) or C. pulchra (Beautiful Tiger Beetle), either of which would be a great find. Alas, overcast skies and a cold, biting wind made whatever tiger beetles were there – lovers of sun and warmth that they are – remain secreted within their protected haunts. I still have a shot at finding out what they are – I successfully extracted two larvae from their burrows and fed them well in the laboratory with fat fall armyworm larvae before putting them to sleep for the winter in a 10°C (50°F) incubator.  If all goes well, I’ll wake them up this spring and finish them out to adulthood this year.

There were a few consolation prizes on the day, one of which was this large, lumbering male tarantula seen slowly making its way down the red clay slopes. For all their charisma and noteriety, it’s interesting to note that the taxonomy of U.S. tarantulas (almost all of which belong to the genus Aphonopelma) is rather poorly known – some 50 species have been described, but many of the descriptions are inadequately based on limited material (or even single specimens) and often rely upon variable, highly artificial characters (Prentice 1997). Brown or black species with no distinctive coloration (such as this one) seem to present the greatest challenge; however, the internet seems to have concluded that the only tarantula present in Oklahoma is Aphonopelma hentzi.


This spider can be distinguished as a mature male by way of the tibial hooks that can be seen on the undersides of the front pair of walking legs in the first photo.  Female and immature tarantulas normally stay in their burrows during the day and come out at night to hunt, but wanderlust strikes the adult males during late summer and fall, during which time they’ve been documented traveling as far as 1.3 km over a period of 2-3 weeks (Janowski-Bell and Horner 1999) – presumably in search of females with which to mate.  It is only after the male’s final molt that wanderlust sets in and the tibial hooks appear, which are said to function in holding the female (and her fangs!) at a safe distance during copulation.


It may seem hard to believe, given its large size and slow movement, but I found this spider exceedinly difficult to photograph compared to the tiger beetles that I have spent much more time with. I’m not used to photographing subjects with a 4-5 inch leg spread, which made it difficult for me to judge working distance and get a handle on proper settings and positions for the flash units. Once I did get that under control, I found the tarantula’s incessant desire to keep moving maddeningly frustrating. Tiger beetles, as active and flighty as they are, nevertheless eventually sit still long enough to allow at least a shot or two before bolting, but this tarantula… just… never… stopped… moving! I can’t tell you how many shots I discarded because it’s legs were splayed awkwardly in multiple directions. Eventually, however, I got enough shots that I felt there should be at least a few good ones among them, and those are the ones I share here.


Most male tarantulas will die within a few weeks or months of their final molt. Still, that doesn’t deter me from scooping them up whenever I find them and bringing them home to enjoy as pets for whatever time they have left. My daughters probably like tarantulas best of any of the critters that I bring home – I never have to ask “Has anybody fed ‘Hairy’?” (and props to awesome wife for enduring something most ‘normal’ wives couldn’t even begin to contemplate).

REFERENCE:

Janowski-Bell, M. E. and N. V. Horner.  1999.  Movement of the male brown tarantula, Aphonopelma Hentzi (Araneae, Theraphosidae), using radio telemetry.  The Journal of Arachnology 27:503–512.

Prentice, T. R. 1997. Theraphosidae of the Mojave Desert west and north of the Colorado River (Araneae, Mygalomorphae, Theraphosidae). The Journal of Arachnology 25:137–176.

Copyright © Ted C. MacRae 2010

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