Wrong lens

During the past couple of years, as I’ve transitioned from strictly a net-wielding entomologist to one that also carries a camera, I’ve had to start making choices about whether to keep the camera in the backpack or hold it at the ready, and if the latter which lens to keep on it. They are situational decisions, influenced largely by what I’m focused on (heh!) at the time—keeping the camera in the bag facilitates collecting, but it also tends to reduce the number of subjects I deem worthy of the setup effort required to photograph them. Conversely, carrying the camera out of the bag greatly impedes collecting but results in much more photographs having been taken. Even when I do decide to carry the camera at the ready, which lens should I have on it—the 100mm for tiger beetle-sized and larger, or the 65mm for tiger beetle-sized and lower? (Annoyingly, most tiger beetles are right at that life-sized threshold, and neither lens alone allows me to float above and below 1:1 for the full range of photos I like for them. As a result, I sometimes end up with extension tubes stacked under the 100mm lens to give me some extra range above its normal 1:1 limit.) I wish there was some way to have the camera with either lens at the ready (and not impeding net swings would be even better), but that just isn’t possible. As a result, I sometimes find myself with the wrong lens on the camera when I see something I want to photograph. If it’s important, I’ll go through the trouble to switch out lenses—hopefully quickly enough to avoid losing the photographic opportunity; other times I might just decide I don’t really need the photo that badly.  Then there are times when I feel a little adventurous and will just go ahead and take the photo anyway without switching lenses.

The following is an example of the latter—an eastern fence lizard (Sceloporus undulatus) photographed with the 65mm lens (minimum magnification 1:1). Not only is this the first time that I have succeeded in approaching one of these lizards closely enough to take a good photograph, but the short working distance of the 65mm required that I get extraordinarily close. He was on the side of a fallen log, and I approached from the other side crouching low, then slowly (slowly!!!) peered over the edge of the log until I had his head in focus. I got off just this one shot, as the flash caused the lizard to bolt for good. The angle could have been better, but I got the eye focused spot-on so it’s a keeper.

Sceloporus undulatus (eastern fence lizard) | Shaw Nature Reserve, Franklin Co., Missouri

I wonder if anybody else has ever photographed a 6-inch long lizard with a 65mm lens…

Copyright © Ted C. MacRae 2011

Brazil Bugs #5 – Lagartixa

On my third night here in Campinas last week, I went out to check the building lights around the hotel grounds.  Surely a fantastical assortment of gaudy, tropical insects would be awaiting me on this hot, humid, summer night in southern Brazil.  Alas, virtually no insects were to be found anywhere – on the walls, in the window sills, under the street lights, or crawling on the sidewalks.  A disappointment, although I’m loathe to complain too much considering the number of insects I’ve encountered during the daylight hours.  I did find a gecko on the hotel wall, however, and although it is not a “bug” the lack of insects at the lights made a photography subject by default.

I’m not at all an expert on reptiles, and certainly those in South America, but I can’t help wondering if this is Hemidactylus mabouia – the tropical house gecko, or lagartixa-doméstica-tropical – an African species introduced to the New World and now widespread from the southern U.S. through much of South America and the Caribbean.

Copyright © Ted C. MacRae 2011

House of Herps #2

House of HerpsWelcome to the 2nd issue of House of Herps, the monthly blog carnival devoted exclusively to reptiles and amphibians.  The brainchild of Amber Coakley, (Birder’s Lounge), and Jason Hogle (xenogere), this new blog carnival had an auspicious start with the inaugural issue and its 21 contributions – an impressive level of participation for a new carnival.  This month the carnival moves off-site, and I am honored to serve as the first off-site host.  The enthusiasm continues with issue #2, for which I received 22 submissions from 18 contributors.  Ever the taxonomist, I present them to you below grouped by traditional classification¹.

¹ It should be noted that modern classification has “evolved” substantially from this traditional classification due to the advent of DNA molecular analyses. For example, lizards are a paraphyletic grouping, and even the class Reptilia has been subsumed within a broader class containing dinosaurs and birds. I stick with the traditional classification here for reasons of familiarity and convenience.

Class AMPHIBIA (Amphibians)
-Order CAUDATA (Salamanders)

California Giant Salamander (Dicamptodon ensatus).  At the nature of a man, Ken talks about not one, but two close encounters last fall with this otherwordly-looking creature.  The first one he saw was a monster of a salamander, measururing a whopping 12 inches (30 cm) in length as it brazenly lounged on a mountain bike trail.  Remaining docile for photographs, imagine Ken’s surprise when the salamander started barking at him when he picked it up to move it to safer ground!  In his second encounter, he got to watch one chomp down on a banana slug – mmm tasty! 

-Order ANURA (Frogs)

Upland Chorus Frog (Pseudacris feriarum).  At Anybody Seen My Focus?, Joan normally only gets to hear the breeding season calls of the chorus frog and his friends who have taken up residence in the water-filled bathtub that serves as a planter in her greenhouse, usually bobbing under the water upon any approach.  But on this occasion, he agreed to photographs, even allowing a final closeup.

Gulf coast toad (Bufo nebulifer).  At Dolittle’s Domain, Dr. Doolittle marvels at one of the many toads that she has found parked under the outside light all night (along with the bats and armadillos) during the cold darkness of December.  Rather than fleeing the camera flash in the face, he simply hunkered down trying to make himself flatter, apparently thinking that would make him invisible and not realizing that he just looked fatter!

Northern Cricket Frog (Acris crepitans).  HoH‘s own Jason weaves artful writing with stunning photographs to distinguish one of the smallest land vertebrates in North America at xenogere.  Despite their ubiquity, these little frogs often go unnoticed due to the smallness of their size, their impressive leap, and their extreme variability.  Get a good look at one, however, and you might notice a key feature or two.

American Bullfrog (Rana catesbeiana).  At Willow House Chronicles, barefootheart looks at frogs on the opposite end of the size spectrum, in fact North America’s largest frog living in an increasingly naturalized man-made pond in eastern Ontario.  These behemoths are more frequently heard than seen by their distinctive “yelp” and splash in response to being approached.  If you are lucky enough to get as good a look as barefootheart did, you might be able to distinguish male from female by looking at its eyes, ears, and throat.

Class REPTILIA (Reptiles)
-Order TESTUDINES (Turtles)

Common Snapping Turtle (Chelydra serpentina).  We have three contributions dealing with these grizzled, ancient, grotesquely beautiful reptiles.  The first one comes from Michelle at Rambling Woods, who shows us how it is possible to tame your pet common snapper (but only to a certain degree).  If her story isn’t enough, she also presents a short video clip on the common snapping turtle (Baby snapping turtleREMEMBER – don’t ever try to catch or hold a snapping turtle with your bare hands!).  In another post, HoH‘s own Amber talks about her attempts to rescue a snapping turtle at Birder’s Lounge.  Fortunately for Amber, the little guy was just a tot – not nearly big enough to prune a digit and thwart Amber’s display of compassion.  It’s amazing how a creature so dinosaurian at maturity can still be so cute as a youngster.  In the third contribution about these fascinating creatures, Marge at Space Coast Beach Buzz talks about her snap (get it?) decision to adopt one of these animals, only to change her mind after discovering its true identity (and before losing any fingers).

Green Sea Turtle (Chelonia mydas).  David at Living Alongside Wildlife notes that while green iguanas falling from trees were a popular news report from the unusual cold snap experienced in the southeatern U.S. last month, they were not the only reptiles so adversely affected.  Sea turtles, populations of which have already been compromised by loss of nesting sites, fishing practices, and trash pollution, also found the coastal waters too cold for normal function.  While natural hardships may be nature’s way, he argues (quite effectively) that it is our responsibility to help mitigate their effects considering the perilous position in which we’ve placed these majestic animals to begin with.

Eastern Box Turtle (Terrapene carolina).  Two contributors submitted posts about these lovable oafs.  At A DC Birding Blog, John posted a photo of a box turtle seen at Brigantine Beach.  He wonders if their always disgruntled look is a result of him disturbing from their activities.  These turtles are easily identified by their bright markings – usually dark brown or olive-colored with bright orange or yellow patterns, dome-shaped carapace, and hinged plastron (bottom part).  Individual turtles have unique designs on their shells, making them identifiable in the field.  Turtles can get worms, believe it or not, and Celeste at Celestial Ramblings adds them to the growing list of animals that she has had to de-worm (including herself, ick!).  Step-by-step instructions and explicit photos combine to show that this is not an easy job, requiring no less than three people – “just another day at the office.”  Hmm – cats look easier!

Diamondback terrapin (Malaclemys terrapin).  The diamondback terrapin is the only species of turtle in North America that spends its life in brackish water (salty but less so than sea water).  At Kind of Curious, John describes efforts by The Wetlands Institute to prevent vehicle mortality caused by terrapins crossing roads in their attempt to reach higher ground for laying eggs.

-Order SQUAMATA
–Suborder LACERTILIA (Lizards)

Common collared lizardCommon Collared Lizard (Crotaphytus collaris).  From Jill at Count Your Chicken!  We’re Taking Over! comes this delightful encounter with one of North America’s most charismatic lizards.  I’ve had my own experiences with these guys, but I’ve never gotten one to crawl on my hat or – even better – gotten one to pose with me for a photograph!

Prairie Lizard (Sceloporus consobrinus).  Near my backyard, Marvin at Nature in the Ozarks presents a nice compendium of this species complimented with beautiful photographs.  Marvin not only discusses identification, distribution, life cycle, habitat, and food, but also comments on the recent DNA molecular analyses that have resulted in a reclassification of the former polytopic “fence lizard” and split up the many subspecies into full-fledged species – a man after my taxonomic heart!

“Culebrilla ciega” (Iberian Worm Lizard) (Blanus cinereus).  Javier at macroinstantes writes an artful blog focusing on natural history of the Iberian Peninsula (it is written in Spanish, but Google can easily translate to English for those who need it).  In this post, he presents extraordinary photographs of this subterranean reptile that is endemic to the Iberian Peninsula.  Traditionally classified in the family Amphisbaenidae, it is now considered to belong to its own family the Blanidae.

“Lagartija de Valverde” (The Spanish Algyroides) (Algyroides marchi).  Javier (macroinstantes) also writes about this small lizard that was only discovered in 1958.  With a global range limited to a few mountain streams in a mountainous area of southern Spain covering less than 2,000 km², it is clasified as endangered on the IUCN Red List.  Like so many of the world’s reptiles, its severely fragmented population is suffering declines due to continuing habitat degradation.

–Suborder SERPENTES (Snakes)

Western Rattlesnake (Crotalus viridis).  On the Colorado front range, Sally at Foothills Fancies had three encounters with this aggressive species on her property.  Fortunately, Sally has a “nonagression treaty” with rattlesnakes and allows them to go about their business as much as possible.  Those that get too close for comfort are humanely relocated rather than simply dispatched.  Sadly, many of Sally’s neighbors are not quite so understanding.

Texas Indigo Snake (Drymarchon corais erebennus).  These snakes do not have any such nonaggression treaty, and David at Living Alongside Wildlife contributes another piece illustrating the rattlenake-eating capabilities for which Indigo snakes are famous.  The photographs in the post show a large individual consuming a Western Diamondback Rattlesnake. David explains how these snakes are often identified as blacksnakes and reveals the characters visible on predator and prey that allow their correct identification.

Black Rat Snake (Elaphe obsoleta).  Right here in my home state, Shelly at Natural Missouri characterizes black rat snakes as one of the most commonly encountered snakes in Missouri.  Large snakes reaching up to 6 feet in length, they often end up in basements and cellars in the fall in search of a place to spend the winter – just in time for Halloween!  These snakes are often needlessly killed because of their resemblance to the venomous cottonmouth or water moccasin that they superficially resemble.  However, Shelly has the same nonaggression treaty with these snakes that Sally has with rattlesnakes (although her husband is not quite so sympathetic). 

-Order CROCODILIA (Crocodilians)

American Alligator (Alligator mississippiensis).  David at Living Alongside Wildlife also contributed two pieces on North America’s largest reptile.  In his post Gatorzilla, he examines commonly e-mailed pictures and text about so-called “giant” alligators, debunking myths about 25 foot long monsters, clarifying the identity of misidentified Nile crocodiles, and exposing cases of camera trickery.  In his post Mommy Dearest, he recounts his nervewracking experience when he stumbled upon an alligator nest while knee deep in a south Georgia swamp at night.  Worse, the babies had hatched!  Read the post to see if David got out of there with both of his legs.

GENERAL HERPETOLOGY

Sometimes simply the act of looking for herps is as enjoyable as the herps that are found.  However, it has been a tough January for Bernard at Philly Herping.  A particularly cold snap in the first half of what is already the coldest month of the year made herping at his favorite cemetary a lesson in futility.   I hope you notice the irony – cemetary?, no sign of life?, cold-bloodedness (okay, okay – ectothermic)?

I hope you’ve enjoyed this issue of House of Herps.  The February issue moves over to xenogere, where Jason’s considerable carnival hosting talents are sure to be on full display.  Submit your slimy, scaley, cold-blooded contributions by Febrary 15, and look for the issue to appear by February 18.

Copyright © Ted C. MacRae 2010

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Florida Scrub Lizard

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The Florida scrub lizard (Sceloporus woodi) is restricted to isolated sand scrub habitats in peninsular Florida.

Tiger beetles were not the only rare endemic species that I encountered during my visit to the Lake Wales Ridge in central Florida last August.  I didn’t know what this small lizard was as I watched it bolt from the trail and scamper for cover during my approach; however, having already found two endemic tiger beetles, I had a feeling that this lizard might also be a good one.  The photo shown here is admittedly not one of my best, but it was the only one I managed to get before the lizard ducked into the brush for good.  Horribly overexposed, I did what I could with it in Photoshop to make it halfway presentable, but there is no question that its subject represents a Florida scrub lizard, Sceloporus woodi¹.  This small, diurnal, ground-dwelling lizard belongs to the family Phrynosomatidae (same family as the Texas horned lizard that I featured in this post) and is restricted to Florida’s rare sand scrub and sandhill habitats.  Like the recently featured Highlands Tiger Beetle, this species is threatened by the isolated, disjunct nature of its required habitat—a threat made worse by the ever increasing pressures of agricultural conversion and urban development.

¹ Sceloporus is derived from the Greek word scelos meaning “leg” and the Latin word porus meaning “hole”, referring to the pronounced femoral pores found in this genus of lizards. The species epithet honors Nelson R. Wood, a taxidermist at the U.S. National Museum who collected the type specimen in 1912.

Distribution of the Florida scrub lizard (from Branch et al. 2003).

The Florida scrub lizard is related to and closely resembles the much more common and widely distributed southern fence lizard (Sceloporus undatus), which co-occurs with the scrub lizard in northern Florida.  Fence lizards, however, lack the dark brown lateral stripe that is clearly visible in the above photo, a feature seen in juveniles and adults of both sexes of the scrub lizard.  Juvenile and adult female scrub lizards also exhibit a dorsal zigzag pattern; however, this fades in males as they reach adulthood and develop the characteristic bright blue belly patches that are seen in both this species and in the fence lizard (Branch and Hokit 2000).  Since light blue patches are just visible on the belly and throat of the individual in the photograph, I haven’t been able to determine whether it represents a mature female or a still-juvenile male—any help from a knowledgeable reader would be greatly appreciated.  Unlike the fence lizard, the scrub lizard displays a high degree of habitat specificity, occurring as disjunct populations in strict association with the major sand scrub ridges of Florida.  The healthiest populations are found on the Mt. Dora Ridge in northern peninsular Florida, on which significant remnants of scrub habitat are preserved in the Ocala National Forest.  Populations also occur on the Lake Wales Ridge of central Florida and the Atlantic Coastal Ridge, but the status of these populations is less secure.  Populations also once occurred along the southwestern coast on the Gulf Coast Ridge, but these populations are now believed extirpated as a result of urban development (Jackson 1973, Enge et al. 1986).  While the Florida scrub lizard is not listed as a threatened or endangered species at the state or federal level, its high specificity to an increasingly isolated and fragmented habitat and its apparently low dispersal capabilities are clear causes for concern over its long-term prospects. As remnant habitats continue to shrink and become more isolated, the threat of localized extinction becomes an increasing concern for the lizard populations that they support.

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Scrub lizard habitat is threatened by development, fragmentation and increased vegetation.

The precarious status of scrub lizards and their occurrence in several disjunct, isolated populations makes them interesting subjects for genetic studies. Mitochondrial DNA analyses suggest that scrub lizard populations exhibit a high degree of phylogeographical structure, with populations diverging significantly not only between major scrub ridges, but also within them (Branch et al. 2003).  The findings support the notion of long-term isolation of scrub lizard populations on the major scrub ridges and confirm their low dispersal rates among adjacent scrub habitats within ridges (as little as a few hundred yards of “hostile” habitat may be sufficient to prevent movement to adjacent habitats).  More significantly, the results support the concept of two distinct morphotypes on the Mt. Dora and Lake Wales Ridges and also raise the possibility that Atlantic Coastal Ridge populations represent a distinct evolutionary entity as well.  These findings are consistent with the hypothesis that scrub lizards evolved in central Florida, where they were isolated when surrounding lands were inundated by rising sea levels during the late Pliocene and subsequent interglacial periods during the Pleistocene.  During periods of low sea level they dispersed to the younger Atlantic and Gulf Coastal Ridges, where they were isolated from parent populations when more mesic conditions returned during the Holocene (12 kya to present).  The genetic distinctiveness of these different ridge populations may justify qualifying each of them for protection as “significant evolutionary units” under the U.S. Endangered Species Act, since it raises concerns about the use of translocations, a common strategy for establishing new populations in restored habitat or augmenting existing populations, as a conservation strategy for the species as a whole.  Since lizards located on different ridges are more divergent than lizards from populations located on the same ridge, movement of lizards between ridges could compromise the integrity of the genetic differences that have accumulated over millions of years and result in loss of genetic diversity.  As a result, augmenting populations on the Lake Wales and Atlantic Coast Ridges with lizards from robust populations on the Mt. Dora Ridge may not be desirable.  Instead, it may be necessary to protect individual scrub lizard populations on each of the major scrub ridges in order to preserve as much of their genetic diversity as possible.

REFERENCES:

Branch, L. C. and D. G. Hokit. 2000. Florida scrub lizard (Sceloporus woodi). University of Florida, IFAS Extension Service Publication #WEC 139, 3 pp.

Branch, L. C., A.-M. Clark, P. E. Moler and B. W. Bowen.  2003. Fragmented landscapes, habitat specificity, and conservation genetics of three lizards in Florida scrub.  Conservation Genetics 4:199

Enge, K. M., M. M. Bentzien, and H. F. Percival. 1986. Florida scrub lizard status survey. Technical Report No. 26, U.S. Fish and Wildlife Service, Jacksonville, Florida, U.S.A.

Jackson, J. F. 1973. Distribution and population phenetics of the Florida scrub lizard, Sceloporus woodi. Copeia 1973:746–761.

Copyright © Ted C. MacRae 2009

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North America’s most bizarre lizard

Hmm, something funny going on here.  This is a bug blog – specifically a beetle blog, yet it’s a post about a lizard that generates a flurry of comments.  I don’t know if lightning will strike twice so quickly, but I did have this second ‘lizard’ post already lined up in the queue.

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The day after seeing a couple of male eastern collared lizards at Four Canyon Preserve in northwestern Oklahoma, I got my second saurian treat with this horned lizard (genus Phrynosoma).  There are actually some dozen species of horned lizards in North America, but the majority are found further west in the U.S. and down into Mexico and Central America.  Of the two that occur in Oklahoma, this particular individual can be identified as a Texas horned lizard (P. cornutum) by the two occipital (back of the head) spines, presence of lateral abdominal finge scales, and dorsal white stripe.  Oklahoma’s other horned lizard (round-tailed horned lizard, P. modestum) is restricted to the northwestern corner of the panhandle and differs from the Texas horned lizard by having four occipital spines, lacking lateral abdominal fringe scales, and more solid pale coloration.

IMG_0392_1200x800Again, my claim of “most bizarre” might be open to debate, as there are certainly many bizarre lizards in North America.  The gila monster once more comes to mind, but I think grotesque is a better descriptor for that animal, and the fan-shaped toe pads of geckos might also get them some votes.  Nevertheless, do a Google search on the phrase “bizarre North American lizard” and the results will be overwhelmingly dominated by references to horned lizards.  It’s no surprise – their squat body form is more suggestive of toads than lizards¹, for which they are commonly called “horned toads” or “horny toads,” and their covering of “horns” (actually modified scales) gives them an otherworldly, almost dinosaurian appearance.  Who among my generation wasn’t terrorized by the sight of these lizards, cheaply magnified, as they threatened the scientists that encountered them in the 60’s sci-fi classic The Lost World?

¹ Even the genus name, derived from the Greek words phrynos (toad) and soma (body), alludes to its toad-like appearance.

IMG_0397_1200x800In reality, these lizards are anything but terrifying.  Instead they employ multiple strategies to avoid being eaten themselves. These adaptations were all on display as I initially passed this individual without even noticing it lying motionless in the middle of the road. Once I had passed I noted movement out of the corner of my eye and turned to see it scurrying towards the vegetation along the side of the road. It’s mottled coloration, blending well with its background, and spine-broken silhouette made it almost invisible. Feeling threatened by my too-close approach, it made a rapid burst for cover, but I cut it off at the pass and blocked its erratic scampers towards the roadside to keep it out in the open so I could take some photographs. Once cornered in the open, it resorted to a third strategy – puffing of the body to make it appear larger. Had I been a true predator, it would’ve had two more strategies up its sleeve that it could have employed as a last resort – bleeding from the eyes (which apparently has a foul taste and will cause a predator to drop the lizard from its mouth) along with the mechanical defense of its hard, spiny scales. Since I didn’t actually try to eat this little guy, I didn’t have a chance to experience these final lines of defense.

The photos here actually represent two individuals – the middle picture is a second lizard that suddenly appeared while I was photographing the first.  The second individual was somewhat smaller than the first and not as boldy marked (note the lack of a distinct dark stripe behind the eye).  Whether these were male and female is difficult to say – horned lizards lack outward sexual characters allow them to be easily distinguished in the field (females do tend to grow a little bit larger). While not threatened or endangered, Texas horned lizards, like many other horned lizard species, have experienced dramatic reductions in its range. Oklahoma has a year-round closed season for both species that makes it illegal to kill or capture horned lizards without written permission. I would see a few more of these fascinating little lizards during my three days at Four Canyon Preserve, suggesting that, at least in this part of the state, horned lizards are doing just fine.

Photo details: Canon 100mm macro lens on Canon EOS 50D, ISO 100, 1/250 sec, f/11-13, MT-24EX flash 1/4 power through diffuser caps.

Copyright © Ted C. MacRae 2009

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North America’s most beautiful lizard

Whew! My fingers and keyboard are still smoking after that long series on Cylindera celeripes (parts 1, 2, and 3). Exciting as my celeripes finds were, there were other “tiger beetle moments” from the Oklahoma trip as well that I want to highlight in future posts. However, I thought I’d give everyone a break from tiger beetles (and my rambling prose) and remind everyone that I can not only talk about other insects, but even non-insects.

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Isn’t he a looker?!  I came upon this this male eastern collared lizard (Crotaphytus collaris collaris) during my first day at Four Canyon Preserve – fitting, since the species is Oklahoma’s state reptile (a fine choice, unlike their dreadfully pedestrian choice for state insect – the honey bee!  Huh?  It’s not even native!).  When I first saw this fellow he skirted under a branch, then across the trail, under a ledge, up and over to another rock…  By the time I got him accustomed to my persistent approaches (remember, I stalk tiger beetles!) he was posing nicely at chest level and with the sun behind my shoulder for a nice series of photographs.  I have never been able to approach a “mountain boomer” this closely before (encountering them only a few times previously on igneous glades in the the St. Francois Mountains of my beloved Ozark Highlands), and the first time I do I have a Canon 50D and 100mm macro lens in my backpack – que suerte!

IMG_0328_1200x800Perhaps my title is a little presumptuous – surely there are other gorgeous lizards in North America.  However, I can’t imagine anything more breathtaking than the vivid blues, greens, and yellows with sharply contrasting black stripes of male eastern collared lizards.  Perhaps the gila monster might get a vote, although its impressiveness is more grotesque than beautiful.  Horned lizards as well are quite impressive, but again more bizarre than beautiful.  Added to the collared lizard’s visual appeal is their comically dinosaurian ability to run swiftly on their hind legs with the fore legs and head held upright (this is how most of my previous attempts to approach them have ended).

IMG_0314_1200x800The name “mountain boomer” probably originated with the early pioneers, who erroneously believed that they emitted sounds that echoed through the canyons and valleys.  An oft-cited theory in field guides (and also the Oklahoma Department of Wildlife Conservation and the Missouri Department of Conservation websites) states that the pioneers may have associated the sunning lizards with the barking of frogs.  This seems unlikely; frogs that make barking noises are creatures of wetlands – far from the rocky outcroppings of the glades and pinyon-juniper, sagebrush, desertscrub, and desert grassland habitats of the central and west-central U.S. where collared lizards are encountered.  Regardless of the source of its nickname, collared lizards in reality make no vocalizations at all (although like most lizards they can hiss when they feel threatened).

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Copyright © Ted C. MacRae 2009

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Tyrant ground beetles

I return to my Afrikaans theme with a distinctive group of ground beetles (family Carabidae) called tyrant ground beetles or spotted ground beetles (tribe Anthiini). I think I prefer the former. This tribe is largely restricted to Africa and is especially diverse and abundant in the arid, sandy Karoo and Kalahari regions of southern Africa (Scholtz & Holm 1985). These beetles are large, powerful predators that rely on speed and agility for capturing prey, and since they are also flightless these characteristics come in handy for avoiding becoming prey themselves. Failing that, they employ chemical defense in the form of secretions from a pygidial gland located in the area of the ninth abdominal segment. The chemical cocktail within these secretions contains concentrated organic acids or quinone that can be squirted at potential predators in a strong jet. This is an effective deterrent to small mammalian and avian predators, and I suppose a careless beetle collector might also regret handling these beetles without due respect. These defensive spray capabilities give rise to another common name for the group, “oogpister” – an Afrikaner word that literally translates to (ahem) “eye pisser.”

Anthia (s. str.) thoracicaDuring my time in Africa, Chuck Bellamy and I were primarily focused on collecting buprestids. However, we still couldn’t resist hanging an ultraviolet light in front of a sheet and searching the ground with flashlights at night to see what diversity of other African insects we might encounter. Truth be told, one of the non-buprestid groups that I’d really hoped to encounter was a near relative of these beetles – the so-called “monster tiger beetles” of the genus Manticora (family Cicindelidae1). We never did see any monsters, but we did encounter several species of anthiine ground beetles around our encampment at Geelhoutbos farm near the Waterberg Range in Limpopo Provice. Anthia (s. str.) thoracica, the giant African ground beetle (above), was the most impressive of these. Click on the photo to see a larger version – only then will it begin to convey how truly appropriate such a common name is for this species. It is certainly the largest ground beetle that I have ever seen – a full 50 mm in length! That’s 2 inches, folks! This species is easily recognized by the depressed lateral expansions of the pronotum covered with dense white/yellow pubescence, and the slightly smaller male that I caught exhibits more elongated mandibles (though not so incredibly as in Manticora) and marvelous lobes extending backward from the pronotum.

1 Increasingly placed within the Carabidae as subfamily Cicindelinae on the basis of molecular phylogenetic analysis, along with Paussinae and Rhysodinae (e.g., Beutel et al. 2008).

Anthia (Termophilum) omoplataIn addition to true Anthia, we saw two species of the subgenus Anthia (Termophilum)2. The species shown right is A. (T.) omoplata3, with the common name “two-spotted ground beetle” (Picker et al. 2002). It was almost as large as its giant brother above, measuring 47 mm in length. Of this species, I only saw this one individual, but I did also find two individuals of a related species, T. fornasinii. Unfortunately I was unable to photograph the latter species, which is equally large but with the elytral white markings limited to a thin marginal band and the surface of the elytra bearing strong longitudinal intervals – a handsome beast, indeed! Picker et al. (2002) mention T. homoplatum being a diurnal hunter, but we found all of our anthiines active nocturnally.

2 Treated variously in the literature as either a full genus or as a subgenus of Anthia. I follow Carabidae of the World, in which it is given subgeneric status. The name is often cited as “Thermophilum” in the literature, but this is an incorrect subsequent spelling according to Alexandre Anischenko (in litt.), coordinator/editor of Carabidae of the World.

3 Usually cited as “homoplatum” or “homoplata” in the literature, but this is an incorrect subsequent spelling (Anischenko in litt.).

cypholoba-alveolataA second genus in the tribe is Cypholoba, represented here by C. alveolata. As far as I can tell it lacks a common name, which is not surprising since it is somewhat smaller than the Anthia species mentioned above. Still, my two specimens measure 38 and 35 mm in length – not puny by any standard. There can be no doubt as to the origin of the specific epithet of this species’ scientific name, with its marvelously alveolate elytra. I don’t think I’ve seen such an extraordinary example of this type of surface sculpturing on a beetle of this size, making the species every bit as spectacular as the larger anthiines.

A truly fascinating aspect of Africa’s tyrant ground beetles is their role as models in Batesian mimicry systems. That these beetles should serve as models is not at all surprising due to their chemical defensive capabilities and obviously aposematic coloration. What is surprising is the mimic – juveniles of the lizard species, Eremias lugubris, in what is believed to be the first reported case of a terrestrial vertebrate mimicking an invertebrate (Huey & Pianka 1977). The juveniles not only copy (roughly) the black and white coloration of anthiine beetles but also mimic their rapid, skitty movements – foraging actively with “jerky” motions and arched backs. Their tails remain somber colored, however, allowing them to blend into the sand. These adaptations combine to give the harmless little lizard the size, color, profile, and gait of the beetles. As the lizards reach adulthood (and their greater size makes them less prone to predation), they take on a more typical cryptic coloration and move in a slower, more deliberately lizard-like manner. This mimicry association effectively reduces predation of the juveniles by potential predators, who quickly learn to avoid the noxious, and more frequently encountered, anthiine models.

REFERENCES:

Beutela, R. G., I. Riberab and O. R. P. Bininda-Emonds. 2008. A genus-level supertree of Adephaga (Coleoptera). Organisms, Diversity & Evolution, 7:255–269.

Huey, R. B. and B. R. Pianka. 1977. Natural selection for juvenile lizards mimicking noxious beetles. Science, 195 (4274):201-203.

Picker, M., C. Griffiths and A. Weaving. 2002. Field Guide to Insects of South Africa. Struik Publishers, Cape Town, 444 pp.

Scholtz, C. H. and E. Holm (eds.). 1985. Insects of Southern Africa. Butterworths, Durbin, 502 pp.