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Mozambique Diary: The Cat mantis

I decided to christen this impressive praying mantis (Heterochaeta orientalis) the Cat mantis, on the account of its head morphology, but even its defensive behavior reminds me of a cranky cat (is there any other kind?).

I decided to christen this impressive praying mantis (Heterochaeta orientalis) the Cat mantis, on the account of its head morphology, but even its defensive behavior reminds me of a cranky cat. (Is there any other kind?)

Arriving in Gorongosa National Park in Mozambique at this time of the year, when the grasslands are bone dry and green has all but disappeared from the color palette of this immense ecosystem, I did not expect to see too many insects. Sure, there will always be ants and a bunch of grasshoppers, but the bulk of the insect fauna pretty much disappears until the onset of rains in November. The nights are quite cold when the atmosphere is devoid of the buffering layer of humidity and consequently few insects are active around the lights of the camp. But those that do come are often stunning. Some of the first animals that I spotted when I resumed my nightly patrols around the lights of the Chitengo camp were huge praying mantids Heterochaeta orientalis, whose head morphology immediately brought to my mind a scrawny, long-eared house cat, and that’s what I decided to call them. The Cat mantids are probably some of the largest in Africa, with the females’ body length approaching 20 cm. Males are about 15 cm long, which still makes for an imposing insect.

Despite his huge size, a Cat mantis (Heterochaeta orientalis) is virtually impossible to spot in its natural setting of bare branches in the woodland savanna of Gorongosa.

Despite his huge size, a Cat mantis is virtually impossible to spot in its natural setting of bare branches in the dry woodland savanna of Gorongosa.

Little is known about this species’ biology. I have always found Heterochaeta on tall shrubs and bushes in the woodland savanna, albeit finding them is definitely not easy – despite their size they are some of the most cryptic insects of Gorongosa. It is enough to take your eyes off an individual sitting on a branch for a few seconds to completely lose sense of its whereabouts. When resting on a branch these insects hold their long raptorial legs outstretched to the sides in an uncanny resemblance of two dead twigs coming off a larger branch, very unlike the typical “praying” stance of other mantids, who tend to hold their raptorial legs neatly folded under the pronotum. The pointy protuberances on the Cat mantis’ eyes enhance the illusion that this animal is just a dead, spiky stick. Clearly, their main defense mechanism is to remain undetected by either predator or prey.

While resting on a branch the Cat mantis keeps its forelegs outstretched to the side, enhancing the illusion of being just another dead stick.

While resting on a branch the Cat mantis keeps its forelegs outstretched to the side, enhancing the illusion of being just another dead stick.

But in addition to its superb crypsis the Cat mantis has another trick up its sleeve when it comes to avoiding being eaten. When I first tried to pick up one of the individuals that came to the light, it immediately responded by rearing up its body, opening the front legs to reveal a bright patch on the underside, and fanning its wings to flash a beautiful, contrastingly yellow and black pattern. This color combination signifies danger (think wasps and their stingers) and many potential predators may pause before attacking the Cat mantis, giving it time to fly away. The mantis is bluffing, of course, as other than a very weak pinch it can deliver with its long forelegs it does not have any real weapons or chemical defenses.

When cornered the Cat mantis rears up to make itself look bigger and flashes beautifully yellow and black hind wings that normally lie hidden under the cryptically colored front wings.

When cornered the Cat mantis rears up to make itself look bigger and flashes beautifully yellow and black hind wings that normally lie hidden under the cryptically colored front wings.

Ever since I first came to Mozambique I have been marveling at the praying mantis fauna of Gorongosa, which is the richest that I have seen anywhere in the world. My species list is approaching 50, but the actual number is almost certainly greater. Their abundance is also exceptionally high, and it is not rare for me to get 5-10 individuals of praying mantids in a single sweep of an insect net across the tall grassland. What drives this richness is something that I am interested in understanding, but it may be related to an equally high abundance of orthopteroid insects, the main prey item of many mantids.

A male Cat mantis at sunset.

A male Cat mantis at sunset.

Mozambique Diary: The stuff of dreams

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Isn’t it fascinating that the same thing can be the subject of one person’s worst nightmares, and another person’s wildest dreams and desires? Nothing illustrates this point better than the Golden orb spiders (Nephila), which my wife doesn’t even call spiders – they are simply her Nemesis, clearly intent on luring her into their enormous webs and tangling themselves into her hair.

But today I had the pleasure of going into the field with two great arachnologists, Matjaž Kuntner and Ingi Agnarsson, who came to Mozambique with one dream and one dream only – to see and catch the largest orb weaving spider in the world, Nephila komaci. This species was discovered by Matjaž a few years ago among old museum specimens, but nobody has seen a live individual since. But there is an interesting twist to this story – the reason Matjaž and Ingi chose Gorongosa to look for this Holy Grail of arachnology was a small photo, a thumbnail really, of N. komaci that had appeared on the old Gorongosa’s website five years ago, two years before the species was officially described. We didn’t know where exactly the photo had been taken, but it had to be somewhere in the park.

We set out early in the morning to look for the elusive weaver, hoping that we might find it in the patches of sand forest in the southern part of the park. Alas, after several ours of trampling through the bush we came back empty handed, not in small part because of some confusion as to where the forest was, which made us end up miles away from our intended destination. But playing bait for lions for several hours this morning was not a complete loss, either. The spider men found a few interesting species, including a related species, the Banded-legged golden orb weaver (Nephila senegalensis). These are gorgeous beasts, huge and beautifully colored. Their orbs are often made of brightly yellow silk, hence the common name. A few years ago Simon Peers and Nicholas Godley used the silk of a related species from Madagascar to weave an extraordinary golden cape.

Tomorrow Matjaž and Ingi will continue their search, this time with a GPS and an even stronger desire to lay their hands on the dreamy arachnid.

Getting low and wide – Part 2

Costa Rican dragonfly (Gynacantha tibiata) drying off its wings after the rain. Taken with a Canon 16-35mm lens with an added extension tube Canon EF 12 II; lighting was provided by a twin flash Canon MT-24EX.

Costa Rican dragonfly (Gynacantha tibiata) drying off its wings after the rain. Taken with a Canon 16-35mm lens with an added extension tube Canon EF 12 II; lighting was provided by a twin flash Canon MT-24EX.

A few days ago I posted the first part of an introduction to wide-angle macrophotography, and here is the conclusion.

Illumination. In order for the illusion that you are a lilliput looking at the giant world to work, the background of a wide-angle macro shot should be well and evenly lit, and the frontmost, focal element of the photo should not be in the shade. One of the most difficult problems to overcome in wide-angle macrophotography is proper illumination of the subject right in front of the lens, which may be just millimeters away. This includes trying to avoid casting a shadow on it. There is not one, simple solution to this problem, and the type of lighting to use will depend on the distance from the lens, time of day, angle of the sun, brightness of the background, reflectance of the subject etc.

In order to get a sharp photo of this Clusia grandiflora flower on the dark, shady forest floor in Suriname I filled a small Ziplock bag with soil and leaves, and used it as a beanbag. This 1 second exposure was taken with a Canon EF 14mm on Canon 7D, illuminated with twin flashes Canon MT-24EX.

In order to get a sharp photo of this Clusia grandiflora flower on the dark, shady forest floor in Suriname I filled a small Ziplock bag with soil and leaves, and used it as a beanbag. This 1 second exposure was taken with a Canon EF 14mm on Canon 7D, illuminated with twin flashes Canon MT-24EX.

What works for me in many cases is a single, remote flash in a softbox (Canon 580EXII in a Photoflex LiteDome XS, either wireless or attached with a Camera Shoe Cord). Because of the proximity of the subject to the lens, a flash mounted directly on top of the camera will not work, as it will cause the shadow of the lens to fall right in front of it. If the subject is not moving (e.g., a flower, an insect sitting motionlessly), and the sun is not directly behind my back, I use a collapsible golden or silver reflector to bounce ambient light at the subject. I also use custom made brackets to mount a pair of small, twin flashes (Canon MT-24EX) about 20 cm away from the front of the lens, which are then diffused with wide pieces of thin, white plastic (made of a cheap plastic folder bought at Staples.) I have also had good experience using inexpensive, flexible brackets DMM-901 (I am not sure who makes these, but they can be ordered here.)

Stabilization. The illumination and sharpness of the background is what often makes or breaks a wide-angle macro photograph. Since it would be difficult to rely entirely on flashes to evenly light the background in a shot that encompasses a part of the landscape, most wide-angle macro photos will require long, often 0.1-2 sec exposures. For this reason a large proportion of my wide-angle photography is made from a tripod. I use a Gitzo GT2531EX, which is light, very sturdy, and allows me to position the camera in any way I want – from close to the ground to 177 cm high. But even a higher number of my photos are taken with the camera resting either on a “beanbag” (in most cases simply a Ziplock bag filled with sand or soil) or directly on the ground. Sometimes, when I am trying to get a really low angle for a subject on the ground, I quickly dig a little hole, place a plastic bag at the bottom (to keep the camera dry), and position the camera in it. In this way the lens is exactly at the level of the ground, or even slightly below it.

Wide-angle macrophotography usually requires long exposures, and thus capturing fast-moving animals is difficult. Here, mammalogist Burton Lim is processing bats collected in Suriname, while small stingless bees are gorging on cornmeal that he uses to dry his specimens. I was able to freeze the action and partially expose the background using twin flashes Canon MT-24EX, and Canon EF 14mm mounted on Canon 7D.

Wide-angle macrophotography usually requires long exposures, and thus capturing fast-moving animals is difficult. Here, mammalogist Burton Lim is processing bats collected in Suriname, while small stingless bees are gorging on cornmeal that he uses to dry his specimens. I was able to freeze the action and partially expose the background using twin flashes Canon MT-24EX, and Canon EF 14mm mounted on Canon 7D.

A stag beetle (Cyclommatus eximius) from the highlands of New Britain, Papua New Guinea. Here I used a Canon 16-35mm with an extension tube, mounted on a full-frame camera Canon 1Ds MkII.

A stag beetle (Cyclommatus eximius) from the highlands of New Britain, Papua New Guinea. Here I used a Canon 16-35mm with an extension tube, mounted on a full-frame camera Canon 1Ds MkII.

For wide-angle photography high in the trees or in situations where a regular tripod or a beanbag cannot be used, I rely on a Gorillapod flexible tripod, which can be wrapped around a branch, providing pretty secure stabilization.
One critically important piece of equipment in wide-angle macro is a remote shutter release, which reduces the chances of vibration caused by pressing the shutter. Recently I have started using a Vello ShutterBoss Timer Remote, which is both less expensive and more functional than the original Canon one.

Camera selection. To say that within the last 10 years the quality of digital cameras has grown exponentially is of course a truism. My cell phone’s camera has twice the resolution and much better low light performance than my first, $5,000 digital SLR (Nikon D1x). You can now walk into a Walmart, and for $399 get an SLR capable of taking photos that were virtually impossible 20 years ago. The latest “pro-sumer” bodies are capable of taking shots in near darkness, and the high ISO performance of almost all SLRs is bound to make you wonder why anybody still uses ISO lower than 400. My point is that cameras have become so sophisticated that no matter which one you chose, the images taken with it can be outstanding. Nonetheless, in wide-angle macrophotography the choice of the right SLR body matters. (I should mention that many point-and-shoot cameras can be a great choice for wide-angle macrophotography, but my experience with them is limited.)

Even in extreme wide-angle closeups, flash illumination is not always required. This molting grasshopper in Suriname was photographed using only ambient light with a hand-held Canon 7D camera and Canon 14mm lens.

Even in extreme wide-angle closeups, flash illumination is not always required. This molting grasshopper in Suriname was photographed using only ambient light with a hand-held Canon 7D camera and Canon 14mm lens.

It may seem counterintuitive that, although you will be using wide-angle lenses, the best cameras for wide-angle macro are not those with a full-frame sensor (35mm equivalent), but rather those with a smaller one. Such cameras give the illusion of producing an image that is magnified, usually by a factor of 1.3-1.6, compared to a full-frame sensor, but in fact the image is simply cropped. Why then buy a wide-angle lens if 30-60% of its coverage is going to be cropped by the small sensor? This is because the shorter (wider) the lens the more likely it is to introduce distortion and chromatic aberration at the edges of the frame, and these faults become more pronounced at close focal ranges, and even more so when the lens is mounted on an extension tube. By using a camera with a sensor smaller than full-frame, you are tapping into the “sweet spot” of the lens – the image captured by the sensor uses mostly the central, sharpest and least distorted portion of the lens, while still retaining the wide-angle perspective (albeit with a smaller coverage.) And of course a camera with a smaller (higher crop) sensor will help you magnify the small, central subject of the photo.

Custom flash brackets that I use in most of my wide-angle macrophotography. They are designed to be mounted directly on the front of the lens, and fit lenses with the diameter of 58-82mm.

Custom flash brackets that I use in most of my wide-angle macrophotography. They are designed to be mounted directly on the front of the lens, and fit lenses with the diameter of 58-82mm.

My favorite camera for wide-angle macro is Canon 7D, which has the cropping factor of 1.6; occasionally I also use Canon 1D MkII, with the cropping factor of 1.3. The only time when I use a full-frame body is when I shoot with a Canon 16-35mm with an extension tube – this is because animals larger than 40 mm or so fill up the frame, and block the background if a camera with the sensor smaller than full-frame is used.

I hope that this brief overview of my approach to wide-angle macrophotography was helpful, and will encourage you to try and perfect your own methods. As with any other photographic techniques, practice makes masters, and no amount of theoretical information will ever replace simply going into the field and chasing critters with your lens. And if you have any specific questions, comments, or suggestions, leave them in the comments below or drop me a line.

A cluster of mushrooms (possibly Hygrocybe sp.) in a New England forest. [Canon 1D MkII, Sigma 15mm, ambient light]

A cluster of mushrooms (possibly Hygrocybe sp.) in a New England forest. [Canon 1D MkII, Sigma 15mm, ambient light]

Getting low and wide – Part 1

Getting low to the ground enhances the illusion that you are as small as the subjects of the photo. I photographed these leaf toads (Rhinella lescueri) in Suriname using a Canon EF 14mm on Canon 7D with an angle viewfinder, and lighted it with a single speedlight Canon 580EXII in a softbox.

Getting low to the ground enhances the illusion that you are as small as the subjects of the photo. I photographed these leaf toads (Rhinella lescueri) in Suriname using a Canon EF 14mm on Canon 7D with an angle viewfinder, and lighted it with a single speedlight Canon 580EXII in a softbox.

Shortly after I had become a proud owner of my first real SLR camera (the wonderful Nikon n6006 – an unexpected Christmas gift from my wife), I decided that what I wanted to do with this magical piece of equipment was to document life that was two or three orders of magnitude smaller than traditional subjects of nature photography. But I wasn’t satisfied with simple macro portraits of katydids and frogs –I was desperate to capture their environment as well, and show a clump of lichens the way a fly sees it – a towering forest, three dimensional, and complex. This, of course, turned out to be easier said than done.

Ever since I saw David Attenborough’s “Trials of Life”, and the mind-boggling sequence of weaver ants tending caterpillars (to this day this remains one of the best macro sequences ever filmed – if you haven’t seen it, buy it right now), I have been obsessed with trying to photograph insects and other small organisms in a way that removes the element of scale. I want to show them as part of the landscape, and see the world from their perspective. It took me a while to figure out that the way to do it is to forget about macro lenses, but instead use lenses designed for much, much larger subjects: wide angle lenses traditionally used for landscape photography. These are lenses of the focal length shorter than 50mm. After many years of trying to get a hang of wide-angle macrophotography I am still hoping to improve my results, but at least I have been able to isolate and try to work on those elements that are needed for a good a wide-angle macro shot. Here are a few tips based on my experience so far.

The greater the depth of field the stronger the illusion that you are part of the scene. This photo of a foam grasshopper (Dictyophorus griseus) from Mozambique was taken with a Canon EF 14mm on Canon 7D, illuminated with twin flashes Canon MT-24EX.

The greater the depth of field the stronger the illusion that you are part of the scene. This photo of a foam grasshopper (Dictyophorus griseus) from Mozambique was taken with a Canon EF 14mm on Canon 7D, illuminated with twin flashes Canon MT-24EX.

Perspective. What truly makes a good wide-angle shot is the impression that you, the viewer, are standing right inside the frame, and that you are looking at the world from the perspective of a mouse. Macro photography that uses lenses of the focal length longer than 50mm enlarges the subject, but a macro photograph taken with a lens shorter than 50mm shrinks the viewer. The shorter the lens the more striking the effect of “shrinkage”, and it is amplified by a low angle of the photo. For example, we never see mushrooms from below, looking up at their underside, and such a perspective enhances the impression of suddenly being transported to the world of towering, giant mushrooms. My two favorite lenses that provide just the right perspective are Canon EF 16-35mm f/2.8L (often mounted on an extension tube – see below) and Canon EF 14mm f/2.8L. Occasionally I also use a Sigma 15mm f/2.8 EX DG Diagonal Fisheye, although this lens creates a very strong barrel distortion of the field of view. A very helpful piece of equipment that allows me to get a ground level point of view is the right angle viewfinder (Canon Angle Finder C).

A tomato hornworm (Manduca quinquemaculata) on tomatoes in our garden. This photo was taken using a Sigma 15mm lens – notice a strong barrel distortion, particularly visible in the curvature of the stick on the right.

A tomato hornworm (Manduca quinquemaculata) on tomatoes in our garden. This photo was taken using a Sigma 15mm lens – notice a strong barrel distortion, particularly visible in the curvature of the stick on the right.

Focus. A wide-angle photograph must have a focal point that is perfectly sharp. Unfortunately, most wide-angle lenses are not designed to focus close enough to fill the frame with subjects as small as insects. Luckily, an inexpensive extension tube can turn almost any wide-angle lens into a wide-angle macro lens. I use a Canon Extension Tube EF 12 II, which allows me to focus on and fill the frame with subjects as small as a grasshopper. The shortest lenses that can be used with it should have the focal length of 16mm or longer – if a lens is shorter than 16mm the point of focus will be inside the lens. Thus, neither Canon EF 14mm nor Sigma 15mm can be used with an extension tube, but luckily both focus close enough so that I have been able to use them to photograph subjects as small as ants (they don’t fill the frame with an individual ant, but that’s not the point of wide-angle macrophotography anyway.)

A column of Matabele ants (Pachycondala analis) returning from a successful raid on a colony of termites in Gorongosa National Park in Mozambique. This photo was taken with a Canon 16-35mm lens with an added extension tube Canon EF 12 II; lighting was provided by a diffused twin flash Canon MT-24EX.

A column of Matabele ants (Pachycondala analis) returning from a successful raid on a colony of termites in Gorongosa National Park in Mozambique. This photo was taken with a Canon 16-35mm lens with an added extension tube Canon EF 12 II; lighting was provided by a diffused twin flash Canon MT-24EX.

Depth of field. The sharper the objects in the background, the stronger the illusion that the frontmost, focal subject of the photo is huge (relative to you, the viewer). In order to achieve a maximum depth of field, use the shortest lens you can and stop the aperture as far down as possible. I usually use the aperture of f/16 or f/22, which means that the exposure time tends to be quite long, often 0.5-2 sec, even in the middle of the day.

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Stay tuned for the second part of the post where I will discuss how to stabilize the camera, illuminate the scene, and select the best equipment for wide-angle macrophotography. In the meantime I highly recommend a recent e-book “Wide-Angle Macro: The Essential Guide” by Paul Harcourt Davies and Clay Bolt, which is filled with great practical information and superb examples.

Wide-angle macro does not necessarily mean that the scene must include a part of the landscape. It can also be used to draw attention to a detail of the main subject, such as the stinger of this scorpion (Pandinus imperator) from Ghana. Here I used a Canon 16-35mm lens with an added extension tube Canon EF 12 II on a Canon 1Ds MkII body; despite the closeness to the subject (its telson was nearly touching the lens) I was able to use a simple reflector to illuminate the scene.

Wide-angle macro does not necessarily mean that the scene must include a part of the landscape. It can also be used to draw attention to a detail of the main subject, such as the stinger of this scorpion (Pandinus imperator) from Ghana. Here I used a Canon 16-35mm lens with an added extension tube Canon EF 12 II on a Canon 1Ds MkII body; despite the closeness to the subject (its telson was nearly touching the lens) I was able to use a simple reflector to illuminate the scene.

A disappearing Goliath

Quickly vanishing forests of West Africa are still home to one of the most magnificent members of the beetle order—the Goliath beetle (Goliathus regius).

Despite their bulky appearance, Goliath beetles are excellent fliers, frequenting flowers blooming in the forest canopy. Adult beetles feed also on ripe fruits and sap, while their giant grubs, which can exceed 150 millimeters in length, develop in the decomposing wood of naturally fallen large trees. It is the increasing shortage of large rainforest trees that may ultimately spell the demise of this and other giant beetles. Their development depends on the availability of old-growth trees, the very same ones that are the principal target of the logging industry. I was lucky to run into this coleopteran wonder on Mt. Bero in Guinea. [Canon 10D, Nikon 17-35mm (yes, a Nikon lens on a Canon body)]

[Read more about the wonderful world of beetles in my book "The Smaller Majority."]

Alien predators in my garden

A portrait of a male of the Chinese mantis (Tenodera parasinensis); this is the individual that came to my lights and bounced off my head [Canon 7D,Canon MP-E 65mm, 3 speedlights 580EXII]

On most nights I like to turn the porch light on, just to see what insects are flying in the neighborhood. Last night I stepped outside to check the light, and was instantly hit by a huge insect that bounced off my head and landed on the ground. To my surprise and delight it turned out to be a giant praying mantis. And not just any praying mantis – this was the largest praying mantis to be found in our neck of the woods, and it was also the second species of these remarkable insects to visit my garden this year.

European mantis (Mantis religiosa) in my garden [Canon 7D, Canon 14mm, MT-24EX twin light]

All my life I have been dreaming of living in a place where winters are mild and mantids are plentiful. Although I cannot say that I have completely fulfilled my dream (winters in Boston are two orders of magnitude worse than in my native Poland), praying mantids are quite common. Two species are found in New England: the European mantis (Mantis religiosa) and the Chinese mantis (Tenodera parasinensis)*, and both were introduced to North America from other places over a century ago. To find native praying mantids in the US you would need to go South to at least New Jersey.

The distinguishing mark of the European mantis is the black and white spot on the inner surface of its front coxae [Canon 7D,Canon 100mm macro, 3 speedlights 580EXII]

Of the two species found in New England, the Chinese mantis is significantly larger, but more slender. Both species come in a variety of colors that range from dark brown to light green, but you can easily tell them apart by two, easy to see differences: the European mantis has a black and white spot between its front legs, whereas the Chinese mantis has dark hind wings (another introduced species similar to the Chinese mantis, Tenodera angustifolia, has clear hind wings, but with a similarly darkened front edge.) Although the European and Chinese mantids are not very closely related – they belong to two different tribes of the family Mantidae – they appear to be attracted to each other, and I have seen individuals of these two different species mating (although such an affair is very unlikely to produce viable offspring.) Speaking of which, females in these two species do occasionally eat their partners during, or shortly after, mating. And yet, somewhat creepily, the abdomen of a half-eaten male continues to copulate with the female. The evolutionary advantage of this behavior is clear – by sacrificing his body, the male directly contributes to the survival of his offspring by feeding the female, and making her more likely to lay a large, healthy clutch of eggs.

The European mantis first appeared in the United States in the late 19th century, most likely introduced inadvertently with nursery plants. Since then it has spread to all states (except Alaska, of course), not in small part because it is being sold as a pest-control agent by many garden supply companies. Alas, praying mantids do not make very good pest-control animals, as they will first go after each other, before starting to eat pests in your garden. The Chinese mantis was apparently introduced on purpose in 1896 (although I have not been able to track down a reliable source of this information), to help control agricultural pests.

A female Chinese mantis devouring a grasshopper [Canon 7D, Canon 100mm macro, 3 speedlights 580EXII]

The impact of these two introduced species on the local insect fauna is difficult to judge. Unlike many other non-native species, praying mantids in New England are not competing directly with any indigenous species. They are generalists in their diet, and they themselves are likely to provide large, nutritious meals to native birds and mammals. The story is probably different further down South and in the western United States, where the introduced species compete directly with native mantids.

Still, I cannot suppress a smile when I see one of these gorgeous creatures, and now that I know that two species of these insects visit my garden, I feel that I can cope with harsh New England winters a little better.

Update (10:23 pm, Sept. 14th, 2012): Kristin has just found another Chinese mantis on our deck!

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*)The Chinese mantis is usually referred to as Tenodera sinensis or Tenodera aridifolia sinensis. However, these names are, technically speaking, junior homonyms, and the scientific name of this species was changed by Daniel Otte in 2004 to Tenodera parasinensis.

A giant among the smaller majority

Coconut crab (Birgus latro) on Guadalcanal, Solomon Islands [Canon 1D MKII, Canon 16-35mm, speedlight Canon 580EX]

While I can honestly say that there is no animal that I find uninteresting, none is higher on my list of the most amazing animals than the coconut crab (albeit this top place in my ranking is shared by many.) The first thing that you will notice about this crustacean is of course its size – it is huge. In fact, with the maximum leg span of 1 m (~3 ft) and weight of 3 kg (6.6 lb), it is the largest invertebrate animal you will find on land. There exist larger marine crustaceans, and there are many much larger cephalopods, but on dry land the coconut crab is the undisputed champion. It is also incredibly long-lived, for a terrestrial invertebrate, reputedly capable of reaching the ripe age of 40 years.

The chelae (“claws”) of coconut crabs are incredibly powerful, capable of cracking open a coconut shell [Canon 1D MKII, Canon 16-35mm, speedlight Canon 580EX]

From the taxonomic point of view, coconut crab (Birgus latro) is more closely related to hermit crabs (infraorder Anomura) than true crabs (infraorder Brachyura), and you can tell that by, among other things, the presence of only 4 pairs of walking legs (true crabs have 5 pairs.) Another giveaway is its life cycle – following a brief period as pelagic larvae, young coconut crabs carry a shell, just like other hermits. Only after reaching the size of about 10 mm the young abandon the shell, and begin to resemble the adults.

Legs of coconut crabs are of different length, perfectly adapted for climbing coconut trees [Canon 1D MKII, Canon 16-35mm, speedlight Canon 580EX]

The transition to the terrestrial lifestyle is more complete in the coconut crab than in any other land hermit. Not only did this species eschew a protective shell of a snail, thanks to its hard, resistant to water loss abdomen, but its senses are more akin to those of insects than crustaceans. All other terrestrial hermit crabs can only detect smells if the air humidity is very high – their olfactory organs are still those of an aquatic animal, and can only respond to chemical cues if they are dissolved in water. Coconut crabs, on the other hand, can smell things in dry air, indicating the development of land-adapted olfaction.

Like all arthropods, coconut crabs need to molt periodically, and the process takes place in a deep underground burrow [Canon 1D MKII, Canon 100mm, speedlight Canon 580EX]

Despite the common name, coconut crabs don’t feed only on coconuts. Like many decapod crustaceans, they are opportunists and will eat anything organic that they can put their powerful claws on (so powerful are their claws that you can easily lose a finger if you are not careful when playing with one.) In addition to cracking coconuts, they have been known to hunt shore birds sitting on their nests at night, steal dog food from people’s backyards, and will gladly eat any kind of carrion. This last habit had them implicated in the disappearance of the famed pilot Amelia Earhart, and you can sometimes hear speculations that her body might have been dismembered and eaten by coconut crabs somewhere around the archipelago of Kiribati after her plane’s crash.
Even if true, it is the crabs that suffer more from our appetite for crustacean flesh than the other way around. Their meat is purportedly deliciously coconutty, and there is plenty of it in an animal of their size. Nor surprisingly, they have been overharvested within most of their range around tropical islands of the Pacific and Indian Ocean, and have virtually disappeared from many places where they used to be common. Many countries that still have these magnificent animals now have laws protecting them, or at least limiting their harvest (one of them is the United States, which protects the crabs on the island of Guam), but an official conservation assessment of this species across its entire range has never been done. Therefore, the coconut crab is still listed as Data Deficient by the IUCN Red List, and its trade is not regulated by CITES. Hopefully this will change in the near future, it would be an unforgivable tragedy to lose this wonder of crustacean evolution.

Live young coconut crabs for sale at a seafood market on Okinawa, Japan [Canon PowerShot SX100 IS]