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Two horned darkling beetle – Neomida bicornis

Last week I met with Catherine Scott and Sean McCann, two talented naturalists and spider-enthusiasts (Catherine studies the mating behavior of black widows, and if you haven’t already, I recommend following her live tweets from experiments). It was great to go hiking together in the snow-covered woods, looking for arthropods hidden inside fallen logs. Before we went on the hike, they brought me a few entomological presents, one of them were lovely beetles that they found during a trip a week earlier.

A pair of two-horned darkling beetles (Neomida bicornis). Ontario, Canada

These magnificent beetles are Neomida bicornis, a species of fungus-feeding darkling beetles (family Tenebrionidae). They are tiny, measuring only a couple of millimeters in length. To the untrained eye they do not even look like darkling beetles, these beetles are like jewels! Their body is very shiny, metallic green in color. The elytra have a bluish tint. Populations of Neomida bicornis in southern North America have an orange pronotum (a true feast of colors, for a darkling beetle at least). The males are characterized by four horns, two of which prominent between the eyes, and two smaller ones on the clypeus (=lip area) above the mouth. The females have no horns. I admit, I have a soft spot for horned insects. What a fabulous gift, thanks again you guys!

These beetle are tiny! That’s the tip of a regular ruler with a millimeters scale.

The female two-horned darkling beetle (Neomida bicornis) is hornless

This species is not rare, but its way of life makes it hard to find: the adults and larvae feed on bracket fungi (polypores) and burrow into this tough substrate, creating inner galleries. According to Sean, these beetles were active inside the mushroom despite the somewhat low ambient temperatures. From what I learned about eastern North American fungus-feeding tenebrionids, they have overlapping generations. In other words, both adult beetles and their larvae can overwinter inside the mushrooms. I will probably try to confirm this at some point but first I need to find out how the larvae look like. They are not the only arthropods taking advantage of a polypore-type shelter from the cold weather.

Male two-horned darkling beetle (Neomida bicornis) inside a polypore mushroom

A Moment of Creativity: A bite from a wandering spider (Phoneutria)

I think the best way to start this post is right at the end. This is me getting tagged by a wandering spider (Phoneutria fera), one of the most venomous and defensive spiders in the world.

Wandering spider (Phoneutria fera) in mid-bite. Oh, the pain!

These spiders possess a potent neurotoxic venom that, if delivered at a sufficient quantity, has the potential to kill an adult human. So, I got bitten and yet I am still alive to brag about this? What is going on?

Things are not always what they seem. This is not a real spider bite. In fact, this is not a spider. This animal is maybe 10% spider. I know one day my twisted sense of humor is going to get me into trouble. I should be careful not to ‘cry wolf’ too many times or I will be left with no friends who care for me.

You might remember that two years ago I encountered a wandering spider (also commonly known as banana spider) under my bed when I visited the Ecuadorian Amazon. That female was guarding her offspring, and what I did not know at the time is that they had already started to disperse from the nest. Some of them found their way into folds in my backpack and hitched a ride with me back home. This happens much more often than you would think. Every day small organisms such as insects, arachnids, snails, and also plant seeds, moss, and fungi find their way into new territories with our help whether we are aware of it or not. Now, there is no need to be alarmed – wandering spiders are not going to spread and take over North America. The vast majority of exotic “traveling” spiders are NOT even wandering spiders, and even if they do pop up every once in a while, the cold winter temperatures and low air humidity will finish them off. In my case, I had a dilemma: to kill the spiders immediately, or to keep them for a while in order to learn more and then donate them for scientific work. I chose the second option. It made more sense to use this opportunity to document this species’ natural history. For example, after two years, even with proper feeding, the spider did not reach its adult stage. They must be long-lived. I should also note that I have a background as a professional arthropod keeper so I knew what I was getting into. This is not something I would recommend to inexperienced hobbyists.

Wandering spider (Phoneutria fera) aka banana spider in my kitchen

Since then, I have been meticulously following the baby spider, sometimes taking ridiculous photos that depict unrealistic situations. Surprisingly, this species seems tamer than its reputation suggests, but caution is always the key. After a while I started pondering the idea of creating an image of the spider in mid-bite. The original idea was to photograph it during feeding, but then a better idea came up. I waited months. Finally, I had what I needed – a fresh molt.

Wandering spider (Phoneutria fera) molt

Yes, what you see in the photo opening this post is nothing but an empty shell. The spider itself was resting in its enclosure during the time I took the photo. Like I said, things are not always what they seem.

Even though this was not a real bite from a living spider, it was still painful. Those fangs (chelicerae) are extremely sharp, and they have no problem piercing through human skin. If you search online you will find photos of people handling Phoneutria spiders with bare hands. That, in my opinion, is pure irresponsibility and a lack of judgment. I will never, ever let these spiders anywhere near my hands. And neither should you. Learn to respect and admire these majestic animals from a distance.

Bombardier beetles – explosions of smoke in your face

I was very positively surprised by the response to my previous blogpost about Epomis. In fact, it now seems that this post is the most popular one on the blog, even more than the ones about the botfly and my NZ accident. How do I top it? Only time will tell. In the meantime, I wanted to mention some of the other ground beetles (family Carabidae) that share the habitat with Epomis. You see, when you start flipping stones and pieces of wood scattered around rain-pools you encounter many carabids. But one group really stands out in appearance, and, as much as it is hard to believe, in sound: the bombardier beetles.

Bombadier Beetle (Brachinus crepitans), one of the cutest species of ground beetles. Golan Heights, Israel

An aggregation of several beetle species found under a rock. Bombardier beetles (Brachinus alexandri) can be seen on the right. Also appearing in this photo: Chlaenius aeneocephalus (Carabidae, metallic colors), and Cossyphus rugulosus (Tenebrionidae) – beautiful beetles camouflaged as seeds! Central Coastal Plain, Israel

Bombardier beetles is a large group comprised of several Carabidae tribes. Here I refer mainly to species of the genus Brachinus. These are small to medium sized beetles, usually with striking aposematic coloration: the body and limbs are bright orange, while the elytra (wing covers) are usually dark green or brown, sometimes with a metallic sheen. These colors serve as a reminder for potential enemies that these beetles can deploy a powerful weapon: an explosion of hot chemicals, which can be aimed at almost any direction.

Two common species of bombardier beetles from Israel: left – Brachinus alexandri; right – Brachinus berytensis

Much has been written about the mechanics and evolution of the beetles’ chemical defense. In short, when provoked the beetle releases two chemicals, hydroquinone and hydrogen peroxide, into a chamber in its abdomen. This mixture, when comes in contact with a catalyst, turns highly combustible due to the oxidation of hydroquinone and the breakdown of hydrogen peroxide to oxygen and water. The chemical reaction starts inside the chamber with temperatures reaching 100°C, and the high-pressure buildup causes the explosion. Then all the beetle has to do is to aim its “nozzle” and fire! The result is a smoke cloud of chemicals at extremely high temperatures. It can momentarily paralyze or even kill arthropod enemies, such as ants and spiders. To us humans (=entomologists who collect the beetles with bare hands) the damage it causes is not so severe, usually nothing but a small stain of burnt tissue, but the effect is coupled with a startling popping sound, and that might be enough for the beetle to escape from a large predator. This complex defense mechanism was used by creationists as an example for intelligent design in debates against evolution. However, it can be easily demonstrated that by gradually increasing the concentration of hydrogen peroxide this defense could evolve in incremental steps without risking the beetles’ existence. If you are still confused, I highly recommend watching Richard Dawkins explaining it here.

Damage to skin caused by bombardier beetle (Brachinus berytensis) chemical defense

Damage to skin caused by bombardier beetle’s (Brachinus berytensis) chemical defense. Not much.

I feel that I must stop here for a brief public service announcement: There are several videos showing the beetle’s defense (you can google them), almost all of them depict the beetle being held in place with either glue or a pair of tweezers. I would like to argue that unless this is being done for research purposes, these actions border on animal cruelty. Sure, it is strange to hear such a statement coming from someone who fed live amphibians to beetles. Still, I want to stress that in the case of the bombardier beetles this is highly unnecessary. The beetles will still put up the same “show” if poked or gently lifted, without causing them much stress and damage, as can be seen from this short video I took almost a decade ago (I mean it, this is a really old video, so please do not judge the quality):

The species shown in the video is Brachinus bayardi, one of the largest species found in Israel:

Bombardier beetle (Brachinus bayardi), Central Coastal Plain, Israel. These beetles are strictly nocturnal, and can be found running on muddy banks of rain-pools in search of prey.

While the chemical defense of the bombardier beetle alone is interesting enough, there is another aspect in their life history that is fascinating. In most species, the adult bombardier beetles are predators of small, soft-bodied invertebrates, but as larvae they feed solely on pupae of other beetles found in the same humid habitat, usually diving beetles (family Dytiscidae) and water scavenger beetles (family Hydrophilidae). This makes them parasitoid insects – their larvae are completely dependent on another insect for completion of their development, usually with fatal consequences to the host. While most parasitoid insects are wasps and flies, in beetles this way of life is relatively uncommon, with only a handful of beetle families exhibiting a parasitoid life history. Despite searching for years, I have yet to find larvae of bombardier beetles, and my attempts to obtain larvae from captive adults has failed so far. I hope this will change one day.

Epomis beetles – insect response to amphibian tyranny

You can say that I am a little obsessed with Epomis beetles. Can you blame me? They are fascinating creatures. It suddenly dawned on me that since the launch of this blog I have not written a single word about the beetles. Unfortunately, there is a lot of misinformation and inaccuracies on the internet, and even in reputable magazines and books featuring Epomis.

It is one of the weirdest animal stories, one in which a small and seemingly harmless animal prevails against a much bigger animal. A unique case of predator-prey role reversal, where the would-be predator becomes the prey. Amphibians, such as frogs, typically prey on insects including ground beetles and their larvae. Among these beetles, one genus managed to stand out and deliver a proper counterattack to its predators. The Epomis larva has impressive double-hooked mandibles that look like they came right out of a horror movie. It waves them around along with its antennae until the movement attracts a hungry amphibian, which approaches quickly and tries to eat the larva. In a surprising turn of events, the larva is able to dodge the predator’s attack only to leap on the unsuspecting amphibian and sink its jaws into its flesh. It then continues to feed on the amphibian, sucking its body fluids like a leech at the initial stage, and eventually consuming it completely. Sounds like science fiction, I know. But it is real. Furthermore, these larvae feed exclusively on amphibians, and refuse to eat anything else. They are dependent on amphibian prey for completion of their development. This makes the predator-prey role reversal an obligatory one, which is very rare in the natural world.

First instar larva of Epomis circumscriptus showing its double-hooked mandibles.

I first learned about Epomis beetles in 2005, when I was working in the Natural History Collections at Tel Aviv University in Israel. They ended up being a great topic for my M.Sc thesis research, and I continue to study them to this day. The genus contains about 30 species distributed in the old world, with the African continent as the center of diversity. They inhabit the banks of rain-pools and temporary ponds, and synchronize their breeding season with amphibians’ metamorphosis into the terrestrial stage. Most of what we know about Epomis comes from studying three species only (in other words, there is more unknown than known). When the main paper from my thesis was published in late 2011, it became an instant hit in the media (see below). However, one main point of criticism was that the supplementary videos showed the interactions between Epomis and amphibians in a lab setting, which might have triggered an unnatural behavior from both. This is a valid point. We needed a controlled environment to test and prove beyond disbelief several hypotheses regarding the feeding habits of Epomis. Nevertheless, I spent the following years going back and recording the same interactions in the field.

Here is a larva of Epomis circumscriptus displaying luring behavior while waiting for a passing amphibian:

And this is the outcome of the above scenario:

To better understand what is happening during this swift encounter, here is a break down of this interaction to several simple steps. As you can tell by the above video, this sequence takes only a split second in real-time:

From enticement to desperation: European green toad (Bufotes viridis) being lured to hunt and getting attacked by a larva of Epomis dejeani. View large!

The larvae are terribly good at this. Even if they are caught by the amphibian’s tongue, they are still able to quickly use their mandibles to grab the amphibian from the inside, whether it is the throat or stomach, and start feeding.

Hard to believe, but this toad is being eaten.

Sometimes the amphibian accidentally steps on the Epomis larva. In this case, the larva will attach to the leg. First instar larva of Epomis dejeani feeding on a Lemon-yellow tree frog (Hyla savignyi).

While the larvae are specialized amphibian ambushers, the adult Epomis beetles are somewhat more generalist predators. They prey on other arthropods and will sometimes go for the occasional earthworm. But these feeding habits only last until they stumble upon an amphibian again. Then, a hidden memory back from the days they spent as larvae kicks in, and they set out to relive their glory days as amphibian slashers.

Epomis dejeani attacking a European green toad (Bufotes viridis) while holding firmly to avoid falling off. Compare to the photo of the larva attached to the leg above.

In a blink of an eye, the beetle sneaks up on the amphibian and pounces on it, holding firmly to avoid falling off. It then moves to the back, and like scissors uses its mandibles to make a horizontal incision, which disables the hind legs and ultimately prevents the amphibian from escaping. As if this was not gory enough, both adult beetles and larvae are particularly fond of eating the amphibian’s eyes. It is like a sick twist of revenge for the insects: after millions of years of suffering under the constant threat of predation by amphibians, they are able to fight back. Not only they hunt their potential predators and slowly eat them alive, but they also cripple them and peck their eyes out right from the start.

Remains of a partially eaten amphibian in the vicinity of temporary ponds are usually a good sign for adult Epomis activity in the area. Central Coastal Plain, Israel

Epomis dejeani guarding a recently captured European green toad (Bufotes viridis). The beetles can get very territorial over prey items.

How did this phenomenon evolve? To be honest, we do not know exactly. But it is possible that somewhere in the evolutionary past, Epomis beetles used counterattack behavior, instead of escaping, as a defense against amphibians. Such behavior could have later evolved into exploiting amphibians as a source of food. The amphibians probably could have not evolved to recognize and avoid this behavior because the majority of insect prey they encounter poses no threat to them, as opposed to the relatively uncommon Epomis beetles. Another interesting point, is that both adults and larvae of Epomis lack any venom, yet the amphibian is quickly subdued and stops resisting after being caught, even while it is slowly being devoured alive.

One common reaction that I get in response to this study is that it was “cruel”, involving poor helpless amphibians that were sacrificed in the name of science. Some people even go further to suggest that I am a sadistic scientist somehow enjoying this. It could not be farther from the truth: This is a natural phenomenon and Epomis beetles must kill and consume amphibians in order to exist. Nature is cruel. We tend to think of amphibians as cute and helpless animals, but from the insects’ perspective they are actually cold-blooded killers (pun intended), gulping every small creature in their path. Moreover, the reality of this study is even harsher: the amphibians would have still died even without me using them as food for Epomis, because the puddles they were found in as tadpoles were quickly drying out. As for myself, I cannot begin to describe the emotional stress I suffered during this research, just so I could bring Epomis’ fascinating biology to the spotlight. I love amphibians, and it was disheartening for me to watch them die so many times. Throughout the study I kept telling myself: “I am going to hell for this, no doubt about it”.

In the past few years I have been following the response to the story of Epomis beetles. More sightings of the beetles are being reported from around the world. There are some excellent blog posts (1,2,3,4, and do not miss Bogleech!), news reports (1,2,3,4,5), videos and TV segments, radio interviews and podcasts, and even Wikipedia pages. Epomis has found its way into artwork. There is a metal band named after the beetles. It is very possible that this is the discovery I will go down in history for, and that is fine by me. Hollywood, I am waiting by the phone for your call. To end this post on a positive note, here is a fitting limerick that I love, written by the talented Celia Warren:

Of the genus Epomis, folk say,
Their larvae at first seem like prey,
But they’ll bite a frog’s throat,
Leave it paralyzed, note!
Then they’ll eat it without more delay.

UPDATE (8 Feb, 2018): I decided to add a gallery page dedicated to Epomis beetles. You can find it here.

Nailing that Megarhyssa shot – it’s all about flexibility

It is intriguing that I do not post much about North American insects. In fact, ever since I moved to Canada I became more and more obsessed with animals found in my home country (Israel). Some might say this is a common case of “you don’t know what you’ve got till it’s gone”, but this does not mean that North American insects are not exciting or interesting. On the contrary, there are many insect species I hope to see in person. One of these insects rewarded us with its presence during a day trip to Hilton Falls Conservation Area in Ontario. I thought I should write about it and share a little bit of the process of photographing it.

Giant ichneumon wasps (genus Megarhyssa) are some of the biggest North American wasps thanks to the females’ long (10cm) ovipositor, which is longer than the wasp’s own body. These wasps might look fierce but they are actually shy and harmless insects. They are parasitoids: their larvae develop as parasites living inside the body of other insects. The female’s ovipositor is therefore not a stinger, but an organ used to inject eggs into the larva’s host.

During our trip we came across an egg-laying female of Megarhyssa macrurus. I only had a couple of small lenses with me and no dedicated macro equipment, but still, I did not want to miss an opportunity to photograph a Megarhyssa during oviposition. I tried to go for a simple wide-angle macro style first:

Wide-angle photo of a female giant ichneumon wasp (Megarhyssa macrurus) during oviposition.

Very quickly I ran across one of the problems I mentioned in this post. The wasp is so thin and delicate and easily gets “lost” in the background, even when it is slightly out-of-focus. To get a better result, I started to cut broad leaves and placed them like tiles in the background. This photo was taken with the same, non-macro lens as above. Surprising result!

Female giant ichneumon wasp (Megarhyssa macrurus) drilling in wood to lay eggs

Megarhyssa wasps attack the larvae of another wasp, Pigeon horntail (Tremex columba), which bore into dead wood. The female can detect tiny vibrations coming from inside the wood by the feeding horntail larvae. She then proceeds to egg-laying: she bends her abdomen, exposing her ovipositor from its flexible sheath, and starts drilling. When she reaches a horntail larva, she sends an egg all the way down the ovipositor and injects it to the host. The parasitoid wasp larva feeds on the host and kills it, and then pupates inside the wood. The new generation of Megarhyssa wasps will emerge as adults in the following summer.

Back to the process of photographing – The next thing I wanted was to test the flexibility of the lens (I always recommend doing this), so I took a few more “creative” shots at different angles. What I like about this photo is that you can also see some of the previous holes this female drilled using her ovipositor.

Giant ichneumon wasp (Megarhyssa macrurus) injecting eggs into horntail wasp larvae found inside dead wood

The last goal was to get a dreamy background, showing some of the light entering through the canopy. This was a bit tricky, because the wasp was facing down towards the ground. Since I do not have special equipment (such as an angle-viewfinder or a tilt-screen), I had to be creative and improvise. Unknowingly, I had my photo taken while trying to compose the shot. I was completely unaware of my pose because I was too focused on photographing, and I guess some of the poses I tried might have been embarrassing for my trip partners… To tell the truth, I had no idea my body was even capable of getting into these positions. If you look closely, you can even see the wasp in this photo, it is very big!

Flexibility is important while photographing insects! Photo by Mio Konfedrat.

After much bending and neck-twisting I managed to get the shot that I wanted:

Female giant ichneumon wasp (Megarhyssa macrurus) in egg-laying

Nice to cross this incredible species off my “wanted” list.

Spoonwings

Last week I posted about Dielocroce hebraea, a species of threadwing antlion found in Israel. The article got a huge positive response and I am more than grateful for that, but I wouldn’t do these mystical insects justice without mentioning the second subfamily of Nemopteridae – the spoonwings (Nemopterinae).

Spoonwings share a close resemblance to threadwing antlions in appearance. They too have extremely long hindwings, but in their case the base of wings is narrow and as these extend further away from the insect’s body they become wider, sometimes bearing several lobes marked in black and white. Some species (members of genus Nemoptera) have similarly decorated forewings, and overall the wings are somewhat iridescent.

Spoonwing (Nemoptera aegyptiaca), Lower Galilee, Israel. Notice the iridescent wings.

Contrary to the cryptic threadwing antlions, the spoonwing adults occur in open sunny places, such as grasslands and meadows. These are showy insects that fly by day, visiting flowers in search for their food – nectar and pollen. They are very fond of Apiaceae flowers, and occasionally several adults can be seen crowding and feeding on the same inflorescence. When they do take off they fly clumsily, slowly bouncing up and down in the air. It is quite difficult to tell which insect they are while in mid-air, but once they land it becomes very clear.

Spoonwing (Nemoptera aegyptiaca) feeding on wild carrot inflorescence, frontal view. Carmel Mountain Range, Israel

Surprisingly, larvae of Nemopterinae are poorly known. Sightings of live larvae are unheard of and most likely there are zero photographs of them out there. We know close to nothing about the life history of these majestic insects. Their eggs are laid on the ground surface, and the hatching larvae quickly burrow into the soil. Unlike the giraffe-larvae of threadwing antlions, they are robust and do not have a long neck. There are several speculations as to where they continue their development and what they feed on. In a paper published in 1995, Monserrat and Martinez described how ants harvest the eggs and young larvae, suggesting that the larvae are myrmecophilous (associated with and living inside ant nests). A few years later Popov (2002) showed that the larvae reject a large variety of arthropod prey, supporting the hypothesis that they are specialists in their diet.

Israel is home to three beautiful species of spoonwings. The most common one is Nemoptera aegyptiaca, which can be observed in activity in late spring. Like most species in the genus Nemoptera, adults can be easily recognized by their decorated forewings. It is hard to describe what it is like seeing them in real life. Cute. I think this is the right word.

Something interesting I noticed about adult spoonwings is that the hindwings are sometimes twisted like corkscrews. I believe this is an artifact caused when they are spreading the wings after emergence from the cocoon. It gives these insects character.

Spoonwing (Nemoptera aegyptiaca) feeding on wild carrot inflorescence. Carmel Mountain Range, Israel

For years I accepted the fact that I may never get to see the other spoonwing species in Israel. I just believed that a lot of luck is involved in finding them, something like being in the right place at the right time. And this is partially true, as I learned a couple of years ago. I visited a site in the Golan Heights (northern Israel), looking for predatory katydids. I arrived very early in the morning, because it is easier to photograph insects during these hours. As the sun came up across the pink sky, I suddenly realized that I am witnessing a mass emergence event of spoonwings. However they were not N. aegyptiaca but Lertha palmonii, a much more delicate and obscure species. Adults were climbing on the dry grasses in dozens, some of them were still in the process of spreading their curled wings. Within minutes they took to the air, flapping their tiny wings and bouncing around me like small birds of paradise. It truly was a magical moment.

Spoonwing (Lertha palmonii) spreading its wings after emergence. Golan Heights, Israel

Spoonwing (Lertha palmonii) with hindwings fully extended. Golan Heights, Israel

Spoonwing (Lertha palmonii), Golan Heights, Israel

The third Israeli species, which goes by the poetic name of Halter halteratus, seems to be very rare in Israel and more common in North Africa. In fact, the majority of spoonwing species occur in Africa, where some impressively large species can be found.

Spoonwing (Lertha palmonii), Golan Heights, Israel

Still not impressed? Check out this Australian species, Chasmoptera huttii, which I nickname “the dragon spoonwing”. If you do not think this insect looks amazing then I have absolutely no idea what you are doing on this website…

Spoonwing (Chasmoptera huttii), Western Australia. Courtesy of Jean and Fred Hort

This photo gives a nice sense of scale:

Spoonwing (Chasmoptera huttii), Western Australia. Courtesy of Jean and Fred Hort

You can see more nice photos of this species here, here and here. These photographs were taken by Jean and Fred Hort in Western Australia, who were kind enough to let me post them here. Their gallery is an impressive collection of flora and fauna from that region, and they have a very keen eye for unique arthropods. I found myself drooling over their beautiful photographs and strongly recommend checking out their flickr photostream.

UPDATE (10 Dec, 2015): Handré Basson photographed another amazing species of spoonwing in South Africa – Palmipenna aeoleoptera. He is a naturalist with a very good eye for finding interesting arthropods, and he shares his beautiful photographs on his Facebook page. I thank him for giving me permission to show his photos.

Spoonwing (Palmipenna aeoleoptera), South Africa. Courtesy of Handré Basson

Spoonwings (Palmipenna aeoleoptera), South Africa. Courtesy of Handré Basson

UPDATE (2 May, 2018): Torsten Dikow brought to my attention that the unique hindwings might have a role in avoiding predators. A study conducted on the species above (Palmipenna aeoleoptera) showed that intact hindwings deterred attacks from small robber fly species, possibly by making the spoonwing appear larger.

Threadwing antlions: giraffe monsters turning into duck-faced fairies

One of the first things I did right after launching my “Meet Your Neighbours” gallery was to ask people which photo draws their attention the most while scrolling down the page. Responses varied, but one in particular was quite dominant: “violin larva”.
The name “violin larva” is not official, but it does great service to describe the insect in question – larva of the threadwing antlion (Dielocroce hebraea). Ever since I read Piotr Naskrecki’s post about these insects I knew I was going to write a post about their larvae. I feel like this is a classic insect one get to see when taking an Entomology course in Israel, but outside the Middle East and Africa not too many people are familiar with them.

Larva of threadwing antlion (Dielocroce hebraea), “violin larva”. Judaean Desert, Israel

Threadwing antlions are interesting animals. They belong to family Nemopteridae, and they are unmistakable in appearance – adults have extremely long hindwings, like thin threads or ribbons, giving the insect its name and the appearance of a delicate fairy when it is in mid-flight. Their larvae are also quite unique for having an extended prothorax (long neck), unlike the bulky larva characterizing the other neuropteran families. Nemopteridae contains two subfamilies: Nemopterinae (spoonwings), in which the day-active adults have wide, ribbon-like hindwings, and the strictly-nocturnal Crocinae (threadwings), containing adults with narrow, thread-like hindwings.

Members of subfamily Crocinae have a narrow habitat preference. They are found in arid desert zones and prefer caves or rock shelves sheltering thick dust patches of fine clay. The larvae are ground dwellers, taking advantage of the fine clay for camouflage. They are voracious predators, using their sickle-shape mouthparts to inject venom into their prey in order to paralyze it. They are characterized by a relatively long neck, almost a half of their total body length. The neck may look like a strange adaptation for life on the cave’s floor, but has several functions.

Larva of threadwing antlion (Dielocroce hebraea) active on cave’s floor. Judaean Desert, Israel

These giraffe-like larvae are sit and wait predators that hide under the fine sand in ambush for passing insects. Here is a video showing the predation of a silverfish by the threadwing larva. See if you can spot where the larva is located before it pounces on its prey:

After watching the video it becomes clear that the long neck may assist in protection from a struggling prey that can damage the larva’s soft abdomen. The variety of arthropods that these larvae feed on include venomous assassin bugs and spiders. But how do the larvae hide themselves so well in the sand? Watch a short timelapse of the process:

The neck also comes in handy when the larva buries itself in the soil. Notice how the larva first checks the area with its head to make sure it is not taken by another already-hidden larva. If the larva’s abdomen is bitten during burrowing by another larva, this can be fatal. The sight of larvae fighting over a spot for burrowing is common, suggesting that they are somewhat territorial, therefore they try to avoid conflict by examining the area before burrowing.

Development of the threadwing larvae is slow, and larvae can spend up to two years living in the fine sand of the cave. Once they complete their development they construct a tiny spherical cocoon from sand grains glued with silk, in which they pupate.

Pupa of threadwing antlion (Dielocroce hebraea). Judaean Desert, Israel

The curled hindwings of the pupa somehow remind me of a butterfly’s proboscis (only there are two, and they are curled backwards). The head bares two “horns” that assist in puncturing a hole in the cocoon, allowing the adult to emerge to the outside world.

Threadwing antlion (Dielocroce hebraea) emerging from its cocoon. The erected “horns” in the mouthparts area are used to burst through the cocoon.

Adult threadwings have elongated heads, with the ventral part extended backwards giving it the appearance of a duck’s bill (some people refer to them as duck-faced antlions, I suggest the name duck-faced fairies though). They rarely feed as adults, although they are sometimes seen drinking dew. Threadwing antlions often rest on spider web found on the cave’s ceiling. It is unclear how they avoid getting tangled by the web. They are so lightweight that they do not apply too much pressure on the silk and thus can rest even on loose strands.

Portrait of threadwing antlion (Dielocroce hebraea). Judaean Desert, Israel

Threadwing antlion (Dielocroce hebraea) resting on the cave wall. Judaean Desert, Israel

Finding threadwings in the wild is not an easy task. You must first find the right type of habitat, and even then nothing guarantees their presence. While I cannot say these insects are common, it is always a treat to stumble upon them. To me they are the closest thing to legendary fairies, hiding a dark secret of their early life as little giraffe monsters.

A plague of locusts

A couple of years ago, I was driving on a desert road in Israel on my way to several night hiking locations. There was nothing too exciting on the sides of the road vegetation-wise, most plants have finished their short flowering period and dried out. It was a late afternoon, and I got carried away in my thoughts about my approaching night hike. Suddenly I saw a vivid yellow splotch on the ground in the distance. Then another one, and another one. Flowers? Maybe, if it wasn’t for the fact that those spots were moving.
No, not flowers. Insects. Grasshoppers, to be more exact.

Desert locust (Schistocerca gregaria) nymphs, Negev Desert, Israel

The desert in bloom? Not exactly.

It is a common mistake to think that locust grasshoppers are a single species. More accurately, “locust swarm” is the name of a natural phenomenon, in which conditions are favorable for the grasshopper population to increase substantially in size. The phenomenon is known from several species of grasshoppers, all members of family Acrididae. The most famous species is the desert locust (Schistocerca gregaria), found mainly in Africa, but there are other species, mostly found in the Old World and Oceania. Only one species was known from North America, the Rocky Mountain locust (Melanoplus spretus), but it mysteriously disappeared in the late 19th century.

Migratory locust (Locusta migratoria), the most widespeard locust species. Photographed in New Zealand

Grasshoppers usually spend their relatively short lives alone, as solitary animals. In the case of locusts however, when food is abundant and space is tight, they start overcrowding and then an interesting chain of events ensues. The physical contact between individuals triggers a set of physiological and behavioral changes, mediated by the neurotransmitter Serotonin. The grasshoppers start moving and feeding together, they change their appearance from harmless-looking, camouflaged nymphs to bold, frantic ones, sporting aposematic coloration of yellow and black. The group stays together even as they mature into adults, then they turn pinkish in color.

Desert locust (Schistocerca gregaria) nymph in solitary phase, Negev Desert, Israel

The adult pink grasshoppers soon double, triple, quadruple in their numbers, and food sources become scarce. Then they start taking off, one by one, and glide with the wind until they find a location with food. Very soon they change their color again, this time without the aid of molting, into yellow. At this stage they are sexually active, and the females start laying eggs in the soil.
About three months later, tiny baby grasshoppers hatch. They move together, as a group, crawling and feeding on any green plant they come across. They grow fast, and soon they form small “streams” of yellow, trying to satisfy their enormous appetite.

Desert locust (Schistocerca gregaria) nymphs in gregarious phase, Negev Desert, Israel

When I visited the Israeli desert in 2013 I knew about the locusts that arrived from Egypt several months earlier. They had already been “taken care of”, and the only traces of them were dead bodies scattered across the desert. Nevertheless, those grasshoppers had already planted the seeds for a new generation, and sightings of dark “spots” made of grasshoppers started to surface and accumulate. I admit not paying much attention to these reports. To be honest, from what I knew about the Ministry of Agriculture and the Plant Protection Services in Israel, I was certain that the locusts would be exterminated immediately. But apparently they decided to wait. Spraying insecticides from the air is a tough decision, because the harming effects can carry on to non-target insects, some of which are beneficial to us (for example bees), and in turn this could also influence the health and survival of insect-feeding animals such as birds and reptiles.
I only noticed the locusts while I was driving near desert sand dunes, when I suddenly saw what appeared to be the road lifting above the ground. The hoppers were trying to avoid being crushed by the wheels of my vehicle, and man, there were thousands of them.

Desert locust (Schistocerca gregaria) nymphs marching, Negev Desert, Israel

This was the first time I have seen this phenomenon in its full glory. I was too hesitant to go when the first recent wave of desert locusts arrived in southern Israel in late 2004, and I kicked myself for missing it. I lucked out again as I was out of the country during the next incoming swarm, but was extremely lucky to be around to witness their offsprings.

The interesting thing about the “marching stage” of locusts is that they are very aware of themselves and of their surroundings. I found it extremely difficult to get close to them without triggering an escape response. As a matter of fact, even when I was lying flat on the ground to seem less intimidating to the grasshoppers, they would still approach and stop at 30cm distance. They would then wait for a few minutes, as if to judge what it is in front of them. If one grasshopper either turned back or jumped, the whole band followed. As much as photography goes I believe the only way to photograph them from up close is to use a timer or lie under some kind of camouflaged blanket.

Desert locust (Schistocerca gregaria) nymphs marching, Negev Desert, Israel

Seeing locusts in the flesh (as opposed to black and white photos of them taken in the 50’s) is impressive. The nymphs move in broad paths that seem endless. Occasionally, a spider or a mantis grabs a nymph as prey, however birds and lizards seem to avoid attacking the hoppers. At night, the locusts can be seen resting in high numbers as they cover bushes and branches, already defoliated from leaves. Some will molt during this time. In the morning they quickly heat up in the sun rays, and go on their way.

Desert locust (Schistocerca gregaria) nymphs crowding at night. Surprisingly, there is one nymph in solitary phase among them (bottom center). Negev Desert, Israel

Desert locust (Schistocerca gregaria) nymphs basking in the sun during the morning hours. Negev Desert, Israel

The sad part about this story is that we usually do not wait long enough to see what happens next. Locust swarms are a destructive force of nature. They can defoliate a crop field within hours. Historically, international alerts were sent whenever a locust swarm was observed airborne. So it came as no surprise to me when I visited the exact same spot the following day, only to find all the locusts dead. Their yellow bodies piled by the thousands under trees and bushes. They were most likely sprayed with insecticides early in the morning, before becoming active. Of all things, this looked like a horrible waste to me. Neither predator nor scavenger came to feed from these now dead grasshoppers, and for a very good reason – they were poisoned. It is none other than a holocaust (of children nonetheless!), but we do not like to think about it this way. We as humans tend to justify our actions when it comes to our own survival as a species. Survival, or world domination? You decide. If only we could accept that grasshoppers are a good food source for ourselves, I believe the response to locust swarms and end result would be slightly different.

Thousands of dead desert locust (Schistocerca gregaria) nymphs after extermination. Negev Desert, Israel

Desert locust (Schistocerca gregaria) adult in solitary phase. This individual was found in the same location two months after I witnessed the extermination of the gregarious nymphs. It is most likely a survivor of that swarm.

Here is a short video of the majestic marching of grasshoppers:

Giving birth to a botfly

Sitting at my dentist chair for 40 minutes and suffering through the shrill sound of the ultrasonic cleaner, I suddenly started to feel contractions from my chest. Oh, no. Not now. Is it really happening? If it happens now this will be a visit I will never forget. Am I getting into labor?

2014 hit me hard in the face with all its goodies, that it was difficult for me to pinpoint the best moments. I still have one more story to share before I bid farewell and move on. For me, 2014 ended with a blast.

The story actually begins in fall 2013. Shortly after returning from BugShot Belize, I noticed that three mosquito bites on my chest were not going away. They became red, started to feel even itchier, and occasionally there was a slight pinprick sensation. I immediately suspected they harbored botfly larvae, and indeed confirmed this after a couple of days when the sensation became more intense.

Hypoderma bovis is a species of botfly that attacks cattle. The resemblance to a bumblebee is not incidental. Upper Galilee, Israel.

Botflies belong to the family Oestridae, whose larvae develop in the body of mammals as endoparasites. They are mostly known as pests of cattle, but also of rodents and other small mammals. At least one species, Dermatobia hominis, attacks primates and, as I learned the hard way, humans. And it does this in the most incredible way: the female botfly waits in ambush for a female mosquito to pass by, and when the blood-sucking insect shows up, a chase ensues between the two. The botfly grabs the mosquito in mid-air and takes her captive to the ground level, where she proceeds to do something unique to Dermatobia botflies – she starts to lay eggs under the abdomen of the now-immobilized mosquito. When she is done, she releases the mosquito from her grasp. Now the botfly has a carrier, a vessel to transport the eggs to a suitable host, preferably a mammal. Once the female mosquito locates a bloodmeal and lands in order to bite, the mammal’s body heat triggers the botfly eggs to hatch, and tiny larvae drop to the mammal’s skin. They quickly start to burrow into the skin, head in first. Some take advantage of existing pores, such as hair folicules or even the mosquito bite itself. The small larvae have several rings of curved hooks pointing backwards; these hooks assist in anchoring the larva inside the host’s tissue and prevent removal. After fully embedded into the mammal’s flesh, the larva (which is a foreign object) excites the body’s immune system, and feeds on the inflammation response and white blood cells that arrive to the area. Its only connection to the outer world is through the entrance hole, now called punctum, from which it extends its spiracles for breathing air.

This beautiful mosquito (Psorophora sp.) is known to be one of the vectors for D. hominis eggs. Photographed in Belize, in the same location where I got my botfly larvae.

When I first learned about Dermatobia hominis in Intro to Entomology course back in 2004, I could not help but wonder how it feels to have an insect living inside one’s body; whether it is painful; and does it show on the outside? Little did I know that I would become a host for the same species 10 years after. Well, it was painful indeed. Sharp, ticking pains that came and went in cycles. I immediately sought medical advice and came across a medical paper describing a method for removing botfly larvae using a suction pump. Fortunately for me, the leading author of the paper was a bus drive away. There was much excitement at the Tropical Diseases Clinic, when several doctors and medical students gathered to see my botflies. We removed three tiny larvae, and I was released home. Then, in the evening of the same day, I felt that sharp pain again from all three locations. Over the next days, the pain became worse, think of chest-stabbing, or corkscrewing in pulses with heated iron and you get the idea. There were larvae still in there. And it seemed they were growing faster because there was no competitor in there with them (the larvae we already removed). To make a long story short, I managed to remove one of these larvae (on Halloween Eve nonetheless!), accidentally killed another at the clinic (only to be removed later by me), and failed to remove the third one. It continued to remind me of its existence with pseudo heart attacks several times every night until it finally died and the punctum sealed over it.

This was quite the experience, and we even published a report of the case in a medical paper. Originally, I wanted to keep one of these larvae until completion of its development. As an Entomologist, I was eager to see the adult fly, let alone this might be the only chance I could give something in return after collecting and killing many insects for my scientific work. However, I was not lucky, and I started to accept the possibility that I will not get another botfly larva, surely not in such a convenient location again. And so, a year later I returned to Belize, not even considering the option that it might happen again. Remembering the lancinating pain that I experienced, I tried to be careful and well-protected from mosquitoes this time. So you can imagine my surprise after I returned home, when I found a new botfly larva in my chest, almost in the same location as last year!

At first I repeated the “routine” of visiting the Tropical Diseases Clinic, but the larva was still too small to be removed. Then I decided to leave the area as is and give the larva the space it needs. I was amazed to find out this larva was not even slightly painful. The feeling was completely different, I could easily feel it moving, but there was no discomfort about it. This is it. I am keeping it.
Maybe I should pause here and say that a botfly is probably the “friendliest” parasite one can wish for. It does not transmit any diseases, does not cause any significant damage to the body, does not leave any scars, keeps its area clean from infections by antibiotic secretions and most importantly – unlike other parasites, once it finishes doing its thing, it leaves on its own!

Portrait of human botfly (<em>Dermatobia hominis</em>) larva. The resemblance to a walrus is incidental.

Portrait of human botfly (Dermatobia hominis) larva. The resemblance to a walrus is incidental.

For more than two months I nurtured the larva, patiently observing while it was growing inside me. Photographing it was not easy, and essentially could only be done facing a mirror, but I learned the trick and eventually got used to operating the gear backwards. It allowed me to take this photo of the larva’s spiracles as it is breathing from the punctum (this might be graphic to some people, so you can view it here). But like I said my real goal was to see the adult fly, and I was restless in the final two weeks of the larval development in fear that I will miss the event. The botfly larva does not pupate inside the host. It first has to leave its host’s body, drops off to the ground and then quickly looks for a suitable place for pupation. In the end, the contractions I felt at the dentist were a false alarm, and I could not feel anything when the larva emerged eventually.

Human botfly (Dermatobia hominis) larva after emergence from its host, searching for a place to pupate.

Incubating the puparium has to be the hardest part in keeping a human botfly. In a fascinating paper from 1930, Lawrence H. Dunn describes how he deliberately allowed two botfly larvae enter his arm to document their development. Only later he found out that prior to his actions he was already infected with four additional larvae (on his other arm and leg). The paper is not an easy read, as it spans through the various sensations and types of pain the author experienced during this period. Eventually he had all his six larvae emerging as late third-instars, pupating and turning into adult flies. Unfortunately, this last part of the paper is poorly written and lack details. How moist was the pupation substrate and what was its composition? Did the larvae burrow or stayed on its surface? How long after emergence the adult flies started activity? And were there any losses during the pupation period? That last question is extremely important because I have heard of many failures in keeping Dermatobia hominis for the purpose of getting adults, and they mainly happened during the pupal stage. This is why I was so thrilled to find the adult fly one afternoon waiting in the container. What a great ending to 2014. And what a magnificent fly it is! Glowing red eyes, a pointy head with a bright silvery “face”, and the most dazzling blue abdomen, striking with metallic gloss. For me, this was literally the miracle of birth. No matter how I look at it, this fly is my own flesh and blood.

Human botfly (Dermatobia hominis) adult, fresh after emergence from its puparium (left)

Larva and adult of the human botfly (Dermatobia hominis). Hard to believe this is the same animal.

Totally worth it.

In this day and age, even a fly can take a selfie.

Was it worth it? Absolutely.

Piotr Naskrecki had his own personal experience bringing (two!) botflies to adulthood. You can read his blog post here. And do not miss the postscript!

UPDATE (12 Jan, 2015): Piotr has just posted a video about his botfly. Please go to his blog and watch it. I cannot recommend it enough; this is most likely the only filmed documentation that follows the botfly throughout its development to adulthood in a human host:
http://thesmallermajority.com/2015/01/12/dermatobia-redux/
Thank you everyone for the positive response to this story!

2014 in review: traveling, wide-angle macro and great finds!

As the clock counting towards the end of 2014, it is time for another year-in-review post. This was a good year. What a refreshing change from 2013. The main element this year seems to be traveling – I did lots of it. I think I broke my own record for traveling by air, sometimes squeezing multiple destinations into the same month, all thanks to the leave of absence I took from the university. It does not necessarily mean I visited new places; there is still a ton I want to see. The surprising thing is that I do not feel like I photographed enough this year. Many of these trips relied heavily on research, and very occasionally I found myself in a conflict between collecting data and photographing.

Here are my best of 2014. I tried to keep the same categories as last year.

The most unpleasant subject

Portrait of human botfly (Dermatobia hominis) larva

Well, botfly again in this category, just like last year. I actually had a human botfly (Dermatobia hominis) in my own body last year as well as this year (there is a scientific publication about it on the way – a topic for a future blog post!). Although I have to say this year’s cute parasite was not at all unpleasant, on the contrary! For this reason I decided to go all the way through and have it complete its larval development inside my body, and now I am eagerly waiting for it to emerge as an adult fly.

The best landscape shots

Bromelia swamp, Toledo District, Belize

Waterfall cave, Cayo District, Belize

I’m afraid I did not take too many landscape photographs this year. I was more concentrated in other methods (see below) that I completely neglected this photography sytle. In fact, I have just sold my trustworthy Tokina AT-X Pro 17mm lens, because I found that I am not using it anymore. I did have a chance to visit some breathtaking places this year, and chose two shots from Belize as my favorite landscapes for 2014.

The most perfectly timed photo

Pinktoe tarantula (Avicularia huriana) on painted wall, Ecuador

This photo is not exactly “perfectly timed” in the sense that I had to wait in order to capture the right moment. As I was walking to my cabin in the Ecuadorian Amazon I saw this pinktoe tarantula (Avicularia huriana) resting on a wall that was painted to show a scene from the rainforest. To my amazement the spider picked the “correct” spot in the painting to rest on, a palm leaf, just as it would be in the real vegetation. The cutesy ants painted marching nearby add a nice twist to this photo.

Best behavior shot

Whip spider (Euphrynuchus bacillifer) molting

This molting amblypygid (Euphrynichus bacillifer) takes this category. I like how it looks like a version of Alien’s Facehugger from this angle.

The best non-animal photo

Caladium bicolor inflorescence

I regard this as one of my best super-macro shots. I have already written a short post about how this unique inflorescence sent me 20 years back in time for a trip down memory lane. What I love about this photo is that I managed to produce exactly what I envisioned.

The most cooperative dangerous subjects

A wandering spider (Phoneutria boliviensis) in “threat posture”. Amazon Basin, Ecuador

You can read more about my scary encounter with the huge Phoneutria spider here. I admit that my hands were shaking as I was getting closer and closer to take a photo. These spiders are fast. And usually quite aggressive too. In the end this female turned out to be very docile, and she also kindly warned me when I was getting too close.

Variable coral snake (Micrurus diastema), Belize

Never in my wildest dreams I imagined I would be photographing a coral snake from a close distance, not to mention doing it alone with no assistance. These snakes have extremely potent venom and should be left alone when encountered. However, in my case an opportunity presented itself and I could not pass on the chance to photograph this beautiful creature. It was carefully released back to the rainforest immediately after the shoot.

The best photo of an elusive subject

Sabethes sp., female in mid-biting

There is almost nothing I can say about Sabethes that I haven’t already said in this post. This mosquito is nothing short of amazing, and for some insect photographers it is a distant dream to photograph one in action. Too bad they are tiny, super-fast, and oh yes – transmit tropical diseases that can kill you. So I guess it fits the previous category as well.

The best natural phenomenon observed

Army ants (Eciton burchellii parvispinum) in their bivouac. Toledo District, Belize

I have seen army ants in the past but this year I was happy to walk upon a bivouac (a temporary camp in which they spend the night). It is such an impressive sight. It is also quite painful if you are standing a bit too close. Taking close ups of the bivouac’s “ant wall” was an unpleasant process, to say the least.
I also love this scene where a small roach watches by while the ants form their crawling “rivers”.

A small roach watches by while an army ant (Eciton burchellii parvispinum) raid takes place. Toledo District, Belize

The best focus-stacked shot

Spectacular male jumping spider (Sidusa unicolor), Cayo District, Belize

I rarely take deep focus stacks. The reason is that I like to photograph live animals and this method requires an almost perfectly still subject. This stack of nine images shows one of the most impressive jumping spiders I had the fortune of finding. You can tell I went all “Thomas Shahan-y” here.

The best wide-angle macro

If there is one style I was obsessive about this year, it is wide-angle macro. I decided to dive in, and experimented with different setups and compositions. I have now gathered enough experience and information to write a long post (most likely split in two) about this method. Stay tuned. In the meantime, here are my favorites from this year.

Leaf-mimicking Katydid (Cycloptera sp.), Amazon Basin, Ecuador

Long-faced grasshopper (Truxalis grandis), Central Coastal Plain, Israel

The next photo comes with its own story: On the way to the 700-Feet Waterfalls in Belize for an Epiphytes survey, Ella Baron (manager of Caves Branch Botanical Gardens), Alex Wild and I joked that it would be cool to take a wide-angle macro shot of a frog against the background of the waterfalls, and to use this “postcard shot” to promote future BugShot Belize workshops. 15 minutes after that, I had the shot on my memory card… This is probably my favorite photo from 2014.

Mexican tree frog (Smilisca sp.), at 700-Feet Waterfalls. Cayo District, Belize

Mexican tree frog (Smilisca sp.), at the beautiful 700-Feet Waterfalls. Cayo District, Belize

The best Meet Your Neighbours photos

Tadpole shrimp (Lepidurus apus). Center District, Israel

Along with wide-angle macro photography, I also photographed intensively against a white background, as a contributor for Meet Your Neighbours project. This technique is easy and produces stunning results that it is difficult to choose favorites. I think I like best the photos that still incorporate some part of the habitat, such as the ones below.

Caterpillar of the crimson-speckled Flunkey (Utetheisa pulchella) on Round-leaved Heliotrope (Heliotropium rotundifolium). Central Coastal Plain, Israel

Stick-mimic mantis (Empusa fasciata), Central Coastal Plain, Israel

Mediterranean Chameleon (Chamaeleo chamaeleon rectricrista). Central Coastal Plain, Israel

Memes

Shooting for Meet Your Neighbours not only gives a chance to appreciate organisms out of the context of their surroundings, but also makes it super easy to use the images in creative ways. I do not consider myself a competent meme creator, but there are times that I have no better way for expressing myself.

One of those mornings.

Sometimes I feel like…

And the most exciting subject…

Ah, where to start? There were so many great finds this year: timber flies, fringed tree frogs, velvet worms, freshly molted whip spiders, eyelid geckos, tadpole shrimps and more. I cannot simply pick one favorite subject. They were all my favorites, so I decided not to end this post with a trail of random photos. I cannot wait to see what I will encounter next year. Have a good 2015!

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Entomologist and Photographer