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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About Ted C. MacRae

Ted C. MacRae is a research entomologist by vocation and beetle taxonomist by avocation. Areas of expertise in the latter include worldwide jewel beetles (Buprestidae) and North American longhorned beetles (Cerambycidae). More recent work has focused on North American tiger beetles (Cicindelidae) and their distribution, ecology, and conservation.
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32 Responses to Tuesday Tarantula

  1. Great pictures, particularly that ‘furry’-faced portrait. It’s at times like this that we can appreciate shooting digital and not film–we can shoot away merrily without having to worry about what ends up being tossed in the trash.

    • Thanks, Adrian. I can’t imagine trying to go through the learning curve I’ve been on using film! I delete almost half of what I shoot right there on the spot and half of what remains once I see things on the computer.

  2. jason says:

    Wow. He’s gorgeous. That face shot really is fantastic. These guys are just so impressive. Definitely looks like a great find on a day when the weather conspired against you. And how lucky that there’s only one species in Oklahoma. I guess that made the ID easy (which is the kind I like!).

    • Hi Jason – thanks! What is it about arachnid face shots that make them so compelling?

      I was astounded to find, while trying to ID the species, that there exists no publication called “Tarantulas of the U.S.” Unthinkable to me for a group with such popular appeal.

  3. TGIQ says:

    Very pretty critter. (Yes, pretty. I may not *heart* spiders, but tarantualas don’t count…those I like). The terrain is lovely too…all those crystals!
    I’ve got my fingers crossed that your slumbering larvae yield great rewards this spring…

  4. MObugs41 says:

    Gorgeous spider Ted, your pictures of him are beautiful. As you know I purchased an “Oklahoma Brown” (hentzi) from a breeder out of Nebraska. I’ve had her for a couple of months and finally this past week worked up enough nerve to hold her. I find that she has a tendency to move about a lot too. After a few minutes of traveling from hand-to-hand she will finally sit still. She is an amazing creature. I can’t wait to use her for upcoming school programs this year. Not to mention she is fun to scare the bejesus outta co-workers…LOL

    • Hi Shelly – you’ve made it further than I would be able to. While I’m fascinated with tarantulas from a natural history perspective, I just can’t get myself to hold one. You will be a hit at the classrooms! I’ll have to stick with my tried and true hissing cockroaches.

  5. randomtruth says:

    Great photos and story Ted. I think we definitely need to put a stanza about critters that ‘just won’t sit still’ in the nature photographer’s blues. It’s the song you sing in your head while you’re trying to get those pics – you know – in between shouting at the beast: “if you’ll just sit still for a moment and let me get a good shot I’ll leave ya alone!” :)

    -Ken

    • Thanks, Ken. I really don’t like to harrass my subjects too much, but I tried stopping him with a stick several times – he would pause just long enough for me to get in position and then start moving right when I was ready to push the shutter. Aaack!

  6. Pete Yeeles says:

    Beautiful spider Ted. Think my wife would freak if I brought one into the house though!!

  7. Eric Eaton says:

    Wonderful images of a beautiful specimen! The text was very informative as well. Best wishes for finishing rearing the tiger beetle larvae.

  8. Marvin says:

    I’m glad you did end up with some great shots — and wrote an interesting post.

    I too find arachnid face shots compelling and wonder why. Maybe because even thought they have multiple eyes, they do not have the large compound eyes that immediately announce “Bug!” in our brains. Just guessing.

    • Thank you, Marvin. Your guess sounds as good as any to me. Arachnid faces are just so otherworldly-looking – I bet you like a good ‘alien’ movie every now and then.

  9. One thing I’ve noticed about entomologists in general, is that they usually collect specimens from the field. When I looked through my new Peterson’s guide to beetles – I noticed that it included an illustration of a “killing jar.” I gotta tell you, I wouldn’t-couldn’t-ever just kill a spider, beetle, other insect, animal, etc. I just can’t do it. And I would worry that removing a male tarantula from the wild might rob a female of her chance at procreating.

    Is it because of the vast number of insects, relative to other species, that we shouldn’t worry about collecting them? I guess I could understand that point of view. Is collecting a vital part of our overall education about these species? And as such, a necessary step on the path to greater appreciation and protection?

    While typing just now, I reflexively smacked a flying…something…that was fluttering around in my “personal space.” Ok, I guess I CAN kill and insect.

    I’m thinking out loud here, and am able to do so comfortably because you’ve become one of my blog-buddies, and I know that you’ll help me understand why the collecting of insects from the wild is not worrisome to those who love them as you do.

    Ted, you always teach me something…please know that I really do want to understand and am not speaking out in criticism.

    • Hi Amber,

      Your question is valid, reasonable, and thoughtfully presented. I appreciate that you feel comfortable in asking for my thoughts on this.

      There are those who unconditionally oppose collecting as a relictual practice – akin to the days when ornithologists shot and stuffed the subjects of their study rather than observing them through the glass. I think such a position fails to consider the enormous difficulties involved in identifying and classifying the most diverse class of animals on earth. Well-curated insect collections – and the recorded data contained within them – represent an invaluable resource for taxonomic research that allows not only the acquisition of basic knowledge but also benefits applied sciences (including conservation efforts). Accurate identification of species is an essential component of such research, and this is often possible only through examination of dead specimens.

      That is not to say that I don’t have a code of ethics regarding how collecting should be done. However, available evidence indicates that for the vast majority of insect species, populations are not impacted by the collection of specimens. Exceptions do occur – primarily species occurring at low densities in restricted habitats and with low dispersal capabilities (examples include the Salt Creek Tiger Beetle, the now-extinct Karner’s Blue butterfly, and a handful of other species currently listed or proposed for listing). These well-studied examples should most definitely not be collected; however, they are the exception rather than the rule. The fact is that we still lack much basic information about the vast majority of insect species. New species continue to be described at the rate of several thousand per year – I have discovered and described several myself, and it would have been impossible to do this without careful comparison of my collected specimens to the already existing accumulated material – both in my collection and in other private and public collections as well. Even for known species, the incompleteness of our knowledge about their distribution, biology, and variation precludes adequate understanding of species limits and ecological relationships. The collective accumulation of material from across their ranges of distribution, well-curated and made available to the scientific community (both during the lifetime of the collector and beyond), helps fill these knowledge gaps and ultimately benefits resource managers by allowing them to make more effective habitat conservation decisions – if we understand what is there and what they are doing, we can better figure out how to give them what they need to keep them there. I’ve done a few posts recently that give an idea of the considerable effort that is often involved in trying to determine the identity of a single specimen – and that is by a specialist with the specimen in hand and full access to primary literature and a good reference collection. For the same specialist in the field, or anyone who is not among this handful of people, the task can be impossible.

      The more real threat confronting insects is habitat loss and alteration. For example, tiger beetles that rely on saline flats in the Great Plains have only one-tenth of their formerly available habitat as a result of human activities, and the habitats that do remain are mostly small and highly fragmented parcels – “islands” in a sea of inhospitality. In addition to their greatly reduced size, these isolated remnants have also been degraded by freshwater runoff and sediment from urban areas, agricultural and landscape chemical runoff, overgrazing, etc. Because these specialized habitat remnants are so reduced in size and quality, the species that rely on them are even more vulnerable to sudden extirpation from flooding or other catastrophic events, and the disjunct nature of the remnants hampers recolonization from other remnants. It is rarely the collecting of specimens that has put these species in their now more precarious situation.

      Regarding the tarantula, scooping an incidental male from the wild late in the season is not going to impact the population (as opposed to systematic removal of females during peak breeding season). It does, however, provide a great educational opportunity for the several dozen school children who see them during my regular ‘outreach’ activities at area schools (including my two daughters). For many of these children, it may be their only chance to ever see a living tarantula or realize that they are a part of the native fauna. For them to see one in the context of a professional entomologist – demonstrating excitement and passion about insects and natural history – hopefully plays at least a small part in creating a new generation that is respectful of nature and more likely to participate in its conservation.

  10. Ted, thank you for sharing your thoughts. I think that if everyone who collects insects shares your code of ethics and purpose, then we are entering into a great era for insects and science. Other species, perhaps more popular in the pet or “medicinal” trades are probably many times more susceptible to serious species peril as a result of take from the wild. (Texas allows the collection of some turtle species, and permits importation and ownership of wild animals from other continents. And this is just info I know off-hand)

    I just ran a quick search at the IUCN Red List website for Coleoptera listed as Endangered, and came up with a total of 33 species (worldwide) – including the (North American) Puritan Tiger Beetle, Cicindela puritana. When I looked at the species account, it had very sparse information, and included the words, “indeterminate,” and “needs updating.” This makes me think that despite the considerable resources of the IUCN, they cannot offer much information beyond the Endangered status. I’m willing to bet you know more about the Puritan Tiger Beetle than is available at the IUCN website!

    I also agree that habitat loss always seems to be among the known or suspected causes of the decline of most species at risk.

    Finally, I am willing to admit my own hypersensitivity to the idea of directly or indirectly harming a living being. I have no business collecting insects, but I wholeheartedly believe that you DO.

    Thanks again, my friend.

    • Yes, that’s the big problem with listing insects – most of them we just don’t know enough about them to really say whether they are truly threatened or just good at avoiding us. Puritan tiger beetle and Salt Creek tiger beetles are valid cases – but so are the Coral Pink Sand Dunes and Highlands tiger beetles, which for some reason can’t make this list despite having among the most restricted ranges of any U.S. tiger beetles. Vastly more beetles are known by few specimens (in many cases just the single holotype), yet it is difficult to nominate them for listing since we just don’t know where they are and what they do. I prefer to take more of a systems approach – protect critical habitats in all their diversity, and the insect/invertebrate/vertebrate associates largely follow. Single-species managment is a much less efficient way of conserving species until you start talking about larger mammals, California condor, etc.

      Anyway, I’m glad you think I do have business collecting insects – it bothers me when people think I’m just in it for the sport.

  11. Allison says:

    Great post, Ted, and like the rest of your readers, mucho impressed with the photos…
    You’re so very good at what you do.

  12. WOW! We have never seen a tarantula in the wild. The golden color of this guy is dazzling! Also, to both Amber and Ted, thanks for openly sharing your feelings and views on a sensitive subject — it’s so nice to see that good, trusting, and caring communication is alive and well on the web.

    • HI K&R – tarantulas, scorpions, and scolopendrid centipedes are but a few of the southwestern delights that just make it into Missouri. We’re not the south, but we’ve got some of the flavor.

      Amber is one of my favorite bloggers. The candor and respect that she showed towards me was deserving of the same in return.

  13. Cindy says:

    Interesting to learn that the tibial hooks don’t appear until the last molt of the male. I found that the tarantulas I photographed on a very hot day last summer would stop if I got low in front of them with the camera (after I scooted them off the road). Only later did I learn that they might have been preparing to spike me with itchy hairs. I spent several subsequent weeks checking out the many webbed holes around the barn waiting for more visitors. I’ve linked your excellent posting from my California adventures:
    http://dipperanch.blogspot.com/2009/09/tarantula-hairs.html

    • Hi Cindy – thanks for visiting, and I enjoyed your account of this beastie in California. I think they must be more common out there than they are here, as I don’t often see their nest entrances.

  14. Joy K. says:

    Wonderful post. I love spiders, and this one is beautiful! The final shot looks rather like Bugs Bunny’s friend, the Big Orange Monster.

  15. Joan says:

    Thanks for sharing these great photos. I love spiders but I’m a little apprehensive around them. Not always sure which ones will bite. And the big ones are just intimidating. Not sure I could look through the viewfinder and not want to be looking around the camera to see where this one was headed. Glad that you could.

    • Hi Joan. Tarantulas, at least our US species, are not at all aggressive – you’d have to try to handle it directly before it would bite, and even then only if you weren’t all that gentle with it. The pictures kind of exaggerate how close I was – I probably had about 10-12″ of working distance with the 100mm lens that I was using, not nearly close enough to alarm it at all. Just remember, all spiders can bite but few actually do, and except for black widows and brown recluses the worst it can be is like bee sting. I’ve never come anywhere close to being bitten by a spider that I was photographing or observing. It can be hard to overcome fears such as this, but they are such magnificently fascinating creatures that making an effort to do so will be well worth it.

      • Joan says:

        Thanks for the reassurance Ted. I do have to relate a story that confirms what you say. I was photographing wildflowers last year and picked a sprig of Gamochaeta purpurea (Spoon-leaf purple everlasting) to get a close-up of the flower. I’m glad I looked below the flower. A male black widow spider was minding his own business. Although I had disturbed his perch, he totally ignored me. I posted the photo here. I was delighted to find him but regretted that I had probably destroyed his chosen real estate.

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