Archive For: Israel

The discovery of Charinus israelensis, a new whip spider from Israel

When I was a kid I used to spend hours in the Israeli outdoors, looking for insects and arachnids in hopes to familiarize myself with as many arthropod species as possible. I was so darn good at finding small critters that soon enough friends requested to tag along to see what I could unearth during a short afternoon hike. My parents recognized my growing passion and got me the natural history “bible” at that time – the 12 volumes of Plants and Animals of the Land of Israel: An Illustrated Encyclopedia. I studied it carefully, trying to set goals to find certain species, which led me on excursions throughout the country. Yet one arachnid seemed to remain out of reach.

Charinus israelensis, a new species of whip spider in Israel

Charinus israelensis, a new species of whip spider in Israel

It looked like a cross between a mantis and a spider, with one long pair of appendages. It was an amblypygid, a whip spider. The book listed only a single species occurring in Israel, Charinus ioanniticus, very rare. It featured a tiny photo, followed by a large illustration on the opposite page, a replication of the photo. In the days before the internet, that was my only reference for this arachnid group.

Amblypygi in: Plants and Animals of the Land of Israel: An Illustrated Encyclopedia

Amblypygi in: Plants and Animals of the Land of Israel: An Illustrated Encyclopedia, Vol. 2 Arachnids. For nearly a decade this was my only reference for information about whip spiders.

I was determined to see a live one, but I always failed to find them. I kept looking at those pages in hopes to memorize every aspect of the animal, making sure I can confirm its identity in case I stumble upon one. Years have passed and I gave up on finding one in the wild. I did get a chance to see a live specimen during my high school days though, in one of the visits I paid to Pinchas “Pini” Amitai, the man who took the original photo in the book. Little did I know that 20 years into the future I would be involved in discovering a new species of whip spider living in Israel.

This discovery is not recent news. We found the new species over five years ago, and the formal description was published last year. The media intended to feature the story, but unfortunately a former president in Israel passed away on the same week the paper was published and there was no interest in a story about an obscure arachnid living inside caves in Israel. Despite that, I waited. The discovery is an important one, and I was hoping our new species could still make an appearance in the news. And as you can imagine, I am still waiting. Well, as the old saying goes – if you want something done, you have to do it yourself.

So let me tell you the story of this cute arachnid. Back in 2012 I stumbled upon a photo of a whip spider from Israel in one of my social media newsfeeds. The photo was taken by Dr. Eran Levin during a cave survey for his research about bats’ hibernation sites. Since I had an approaching trip to Israel I contacted my friend and asked if he would share the location, because I was still hoping to see and document a wild whip spider in my home country. We chatted for a while, the location was a bit unexpected for amblypygids in the area, but a few months later I found myself crawling through a tight opening into the warm cave. And indeed they were there, happily roaming on the walls, waving their magnificent long legs everywhere.

A juvenile of Charinus israelensis walking on the wall in one of the caves

A juvenile of Charinus israelensis walking on the wall in one of the caves

Molts hanging from the cave's ceiling are a good sign for an active whip spider population.

Molts hanging from the cave’s ceiling are a good sign for an active whip spider population.

Charinus israelensis cleaning its leg

Charinus israelensis cleaning its leg. This specimen lost two of its legs in fights with others (see example below). They will grow back the next time it molts.

I took some photos and happily went home. When I inspected the photos later, something did not sit right with me. I still had a vivid memory of the photo and illustration in the book from my childhood. But now, I could also use information online for confirmation. The amblypygid species known from Israel, Charinus ioanniticus, has well developed median eyes. It almost looks like it is crossed-eyed. How cute.

Charinus ioanniticus' big smile. See the tiny beady eyes? Adorable!

Charinus ioanniticus’ big smile. See the tiny beady eyes? Adorable!

I looked at my photos, and none of the animals had median eyes. What is going on here?

Charinus israelensis, note the absence of median eyes

Charinus israelensis, note the absence of median eyes

Charinus israelensis can have big smiles too

Charinus israelensis can have big smiles too

In all other visible aspects the whip spiders looked like C. ioanniticus, yet the absence of eyes was enough for me to suspect that I might be dealing with a new species. I made some calls, went back to collect some specimens, and started the long process of verifying and describing the species with colleagues (you can find our paper on my publications page). I invested my energy and personal funds into that research. For me it was a mission to put the spotlight on this exciting new find. We named it Charinus israelensis. I became heavily involved with the general public and posted requests in forums and social media groups for any records or sightings of whip spiders in Israel. Slowly but surely, I started receiving responses from various people located throughout the country. Some of which mentioned whip spiders that found their way into homes, others were reported from natural caverns. It was even more interesting to visit some of those places with the people who made the sightings, and witness the whip spiders’ populations together with them. I learned a lot about caves in Israel, and how much we still don’t know about these habitat systems. But the best experience for me while searching for the new species C. israelensis was to discover new unrecorded populations of the known species, C. ioanniticus. And more than anything, I suddenly realized that they are not at all that rare as mentioned in the old encyclopedia. They are just extremely cryptic, remaining hidden in tight crevices and coming out in the darkest of nights. No wonder people never see them.

Charinus ioanniticus from a newly recorded population in the Carmel Mountain Ridge of Israel

Charinus ioanniticus from a newly recorded population in the Carmel Mountain Ridge of Israel

Why is this exciting? There are two main reasons. The first one is that this discovery doubles the Amblypygi fauna for Israel. It may not sound much, but jumping from one species to two is actually a big deal. It has implications on our understanding of food webs in caves, and these unique arachnids may give further incentives to protect and conserve cave habitats in Israel. The second reason is that the loss of eyes in cave animals (troglomorphism, a term associated with adaptation for life in dark caves) is an interesting topic for studying the evolution of traits within a phyllogenetic lineage. There are already several examples of blind Charinus whip spiders from around the globe, which may lead to fascinating research in the future. In the meantime, I continue to keep live specimens of both Charinus species from Israel, learning a ton about their biology in the process.

A freshly molted Charinus israelensis shows spectacular coloration

A freshly molted Charinus israelensis shows spectacular coloration. The color turns reddish-brown after some time.

Two females of Charinus israelensis fighting

Two females of Charinus israelensis fighting. Whip spiders have complex communication based on movements of their antenniform legs. Some encounters turn hostile, in this case because the bottom female was gravid.

Charinus israelensis female carrying an egg sac

Charinus israelensis female carrying an egg sac

Some of the adult whip spiders that were collected in the beginning of the research are still alive and kicking! Quite impressive for a small arachnid, and seems like they can even outlive some of the more “conventional” pets.

Because I eat, sleep, and breathe whip spiders, my friend Peggy Muddles aka The Vexed Muddler made this awesome portrait of mine with C. israelensis (check out more of her fabulous stuff here)

artwork by Peggy Muddles

“Whip spiders are the coolest arachnids that will never hurt you”

By the way, this weekend (Sunday August 27th, 10am-5pm) the University of Guelph is holding a “Bug Day” at the Arboretum Centre. Come for a fun day out and learn about arthropods. I will have a table with whip spiders, so please drop by and say hi. I will also have some framed whip spider molts with me so please come and check them out!

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

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

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

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.

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.

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 (Pseudepidalea viridis) being lured to hunt and getting attacked by a larva of Epomis dejeani. View large!

From enticement to desperation: European green toad (Pseudepidalea 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.

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).

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 (Pseudepidalea viridis) while holding firmly to avoid falling off. Compare to the photo of the larva attached to the leg above.

Epomis dejeani attacking a European green toad (Pseudepidalea 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

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 (Pseudepidalea viridis). The beetles can get very territorial over prey items.

Epomis dejeani guarding a recently captured European green toad (Pseudepidalea 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.

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.

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

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

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) spreading its wings after emergence. Golan Heights, Israel

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

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

Spoonwing (Lertha palmonii), 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

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

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

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

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

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

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

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

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

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

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

 

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

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

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

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.

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

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

Threadwing antlion (Dielocroce hebraea) resting on the cave wall. 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

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

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

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

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

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

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

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 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

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

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.

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:

 

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

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

Bromelia swamp, Toledo District, Belize

 

Waterfall cave, Cayo 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

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

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

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

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

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

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

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

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

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

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

 

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

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

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

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

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

 

Mediterranean Chameleon (Chamaeleo chamaeleon rectricrista). 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.

I slept too much

One of those mornings.

 

Kung Fu weevil

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!

Acrometopa syriaca – Mediterranean leaf katydid

Along with the predatory Saga katydids, Acrometopa syriaca is one of my favorite katydid species in Israel. There is something unique about its appearance; it almost looks like a tropical katydid that does not belong in the Mediterranean region. This species does not have a common name, so I suggest – “Mediterranean leaf katydid”. In my opinion, there is no other katydid in this area more deserving to be called a leaf-mimic.

When I visited Israel in early spring this year, I could only find tiny katydid babies. They were very easy to recognize as Acrometopa by the pale, extremely-long-yet-thick antennae, which are rich in sensory hairs. Apart from Acrometopa, only Saga species have thick antennae, whereas all other katydid species in Israel have relatively thin antennae.

Baby Mediterranean leaf katydid (Acrometopa syriaca) on a blade of grass, Upper Galilee, Israel. Note the thick hairy antennae, used to detect approaching predators and enthusiastic macrophotographers.

Baby Mediterranean leaf katydid (Acrometopa syriaca) on a blade of grass, Upper Galilee, Israel. Note the thick hairy antennae, used to detect approaching predators and enthusiastic macrophotographers.

 

Juvenile Mediterranean leaf katydid (Acrometopa syriaca) are characterized by the wing buds, resting on their back like miniature backpacks. Central Coastal plain, Israel

Juvenile Mediterranean leaf katydid (Acrometopa syriaca) are characterized by the wing buds, resting on their back like miniature backpacks. Central Coastal plain, Israel

 

There is very little chance to mistake adults of Acrometopa syriaca with another katydid species. It is big (can easily reach 12cm leg span, even longer if antennae are included), slow, and rarely jump. Apart from its characteristic antennae, it is always green, and has wide forewings that have both the color and texture of a leaf. This excellent camouflage makes it very difficult to find the katydid when it rests on bushes or small trees. Females are rounder in their appearance, while the males have longer hind wings that extend beyond the forewings. In addition, this species’ huge hind legs are unmistakable.

Male Mediterranean leaf katydid (Acrometopa syriaca), Golan Heights, Israel

Male Mediterranean leaf katydid (Acrometopa syriaca), Golan Heights, Israel

 

I just happened to be lucky enough to visit Israel again in early summer, and I was hoping I could find some adults. Even though this species has a relatively wide distribution throughout the country, I drove to the Golan Heights in the north, because I have always been under the impression that they are easier to locate there. But I found nothing. I returned frustrated to the Central Coastal Plain, only to find an adult female very close to the place I was staying at. Obviously, I could not resist the temptation to photograph her for Meet Your Neighbours biodiversity project.

Female Mediterranean leaf katydid (Acrometopa syriaca) from the Central Coastal Plain, Israel

Female Mediterranean leaf katydid (Acrometopa syriaca) from the Central Coastal Plain, Israel

 

But it was not over just yet, for this katydid was also a fine candidate to test something I wanted to do for a very long time: photography of fluorescence under UV.
I have photographed UV fluorescence of arthropods in the past; scorpions are usually the default subjects for this style of photography, because they show intense fluorescence even under long wavelengths in the UV range (380nm-395nm). This makes photographing “glowing” scorpions very easy with cheap UV torches (you can see examples of such photos in my scorpions gallery).
Things get more interesting under a shorter wavelength, specifically 365nm and shorter. I will not go into details here because I plan to write a bigger post about UV photography, but I will just say that many unexpected things start to fluorescence when exposed to this light, including representatives of several insect groups. I suspected that Acrometopa syriaca would “glow” because other members of the same subfamily, Phaneropterinae, were also found to show fluorescence under 365nm UV light. And as expected, it did not disappoint: when I shone my torch the whole katydid became bright turquoise in color – just stunning!

Female Mediterranean leaf katydid (Acrometopa syriaca) fluorescence under UV, Central Coastal Plain, Israel

Female Mediterranean leaf katydid (Acrometopa syriaca) fluorescence under UV, Central Coastal Plain, Israel

 

A pleasant surprise – Prosopistoma phoenicium

During my visit to Israel I visited the Golan Heights with colleagues from Israel and Germany. We were looking for mayflies and ground beetles in particular, but I was interested in anything I could find that would be nice to photograph.
We stopped at one of the fast-flowing springs in the Hula Valley and started flipping rocks in search for unique aquatic invertebrates. It wasn’t too long before we found something interesting: small creatures crawling on the surface of submerged rocks. There was no doubt – these were larvae of Prosopistoma phoenicium.

Typical habitat of Prosopistoma phoenicium larvae, fast-flowing streams (or springs, such as this one) with a rocky substrate.

Typical habitat of Prosopistoma phoenicium larvae, fast-flowing streams (or springs, such as this one) with a rocky substrate.

 

It is important to pause for a moment to reflect on the scientific history of this animal. Viewed from above, its appearance bears a striking resemblance to that of tadpole shrimps, branchiopods of the order Notostraca. And indeed, for many years this creature has baffled taxonomists regarding its true identity.
When Prosopistoma was discovered in 1762 by Geoffroy, he initially described it as a species of Binoculus, a crustacean, due to the curved, shield-like mesothorax. This changed in 1833, when Latreille described the genus Prosopistoma and separated it from arguloid crustaceans, but still considered it to be a branchiopod along with the tadpole shrimps. Later in 1868, more than 100 years after the first discovery, Emile Joly realized that Binoculus/Prosopistoma was in fact a mayfly larva. Viewed from below, the animal clearly shows three pairs of legs, in other words – it is an insect, not a crustacean. Finally, Hubbard completed the required transition between the taxonomic groups by providing a revision of the nomenclature in 1979. As of today, the family Prosopistomatidae contains about 20 described species with a distribution primarily in the old world, throughout the Palaearctic, Oriental, Australian and Afrotropical regions, but entirely missing from the New world, the Nearctic and Neotropic regions.

Larva of Prosopistoma phoenicium from the Golan Heights, Israel. Left: dorsal view; right: ventral view.

Larva of Prosopistoma phoenicium from the Golan Heights, Israel. Left: dorsal view; right: ventral view.

 

These insects are rarely seen, but in Israel they seem to be easy to find if one knows where to look. I would like to take this opportunity to thank the Entomology course staff at Tel Aviv University in Israel, who did a splendid job with students in the field (I just realized I took this course as a student more than 10 years ago. Time flies when you’re having fun!). Without them I would not know where to look for and how to recognize this insect, as well as other cryptic species.

The biology of Prosopistoma is poorly known, but it is believed that the larvae scrape and feed on organic matter, such as algae, from the surface of rocks submerged in fast-flowing streams and springs. Adults are almost unheard of from the wild, most of the currently recognized species of Prosopistoma were described from characteristics of the larvae, and the adult mayflies are known from three species only. In the case of our site, the population was very healthy and we could afford to collect quite a few larvae for laboratory rearing at Tel Aviv University. I hope they complete their metamorphosis successfully as I am hoping to see an adult Prosopistoma one day!

The incredible tadpole shrimps

One of the creatures I wanted to find during my visits to Israel is a big crustacean, found only in temporary ponds during a specific time of the year. In previous years I was unlucky to find it – I visited in the late spring and early summer, and most of the rain-pools were already gone or in the process of drying out.

But this year I planned my trip way ahead, making sure to save some time for searching these animals.

Tadpole shrimps belong to the small order Notostraca, which contains a single family, Triopsidae, with only two genera: Triops and Lepidurus. These animals are considered living fossils, having not changed significantly in appearance since the Triassic period, about 200 million years ago. They also bear a strong resemblance to horseshoe crabs, characterized by a broad, shield-like carapace, which conceals the head and bears three eyes, a pair of compound eyes and a nauplius eye between them. The abdomen is long, and ends in two caudal filaments. But in my opinion, the real wonder about tadpole shrimps is their large size. Some species can reach a whopping length of 10cm, larger than most insects and amphibian tadpoles co-habiting in the same pond. And indeed, many people I met while surveying rain-pools could not believe that this was a crustacean until I pulled one out of the water.

Temporary ponds like this one are home to various aquatic invertebrates such as the tadpole shrimps. Unfortunately, these habitat are threatened with destruction in Israel. Here a low wooden fence is the only physical barrier between this small nature reserve and a sand quarry found behind the pond.

Temporary ponds like this one are home to various aquatic invertebrates such as the tadpole shrimps. Unfortunately, these habitat are threatened with destruction in Israel. Here a low wooden fence is the only physical barrier between this small nature reserve and a sand quarry found behind the pond.

 

Portrait of a Tadpole shrimp (Triops cancriformis), showing two compound eyes and a middle nauplius (larval) eye.

Portrait of a Tadpole shrimp (Triops cancriformis), showing two compound eyes and a middle nauplius (larval) eye.


There are two species of tadpole shrimps in Israel. The bigger one, Lepidurus apus, is relatively common and can be found in many ponds along the coastal plain from winter to the early spring. It is easy to recognize – not only is it big and brightly colored with red and olive-green, but it also sports a wide transparent scale at the end of its body, between the two caudal filaments.

Tadpole shrimp (Lepidurus apus). The bright red color indicates presence of hemoglobin, an adaptation for life in habitats poor with oxygen.

Tadpole shrimp (Lepidurus apus). The bright red color indicates presence of hemoglobin, an adaptation for life in habitats poor with oxygen.


The second, smaller species, Triops cancriformis, is much more scarce, and in fact is known only from a handful of ponds. This species is critically endangered in Israel due to habitat destruction, however it was recently recorded from a new location, a water reservoir in the Arava desert, the southernmost point in its distribution to date. A little less colorful than its close relative, it is mottled with green and grey splotches that assist in blending in with its surroundings.

Tadpole shrimp (Triops cancriformis) digging in the sediment. The green and grey splotches make excellent camouflage for concealing it from predators striking from above, such as water birds.

Tadpole shrimp (Triops cancriformis) digging in the sediment. The green and grey splotches make excellent camouflage for concealing it from predators striking from above, such as water birds.

 

A side view of a tadpole shrimp (Triops cancriformis) revealing eleven pairs of legs. The first pair is long and modified to function as a sensory organ.

A side view of a tadpole shrimp (Triops cancriformis) revealing eleven pairs of legs. The first pair is long and modified to function as a sensory organ.


Both species are omnivores, living on the bottom of the pond while relentlessly digging in the sediment searching for food. Occasionally they are seen swimming close to the water surface, especially in shallow parts of the pond, where they are usually mistaken for amphibian tadpoles, hence their common name.
But the most fascinating fact about the life cycle of tadpole shrimps is that similarly to other aquatic invertebrates they too must face the inevitable faith of the temporary pond: drying out. For them, it is a race against time; they must grow fast, mate and lay their eggs before the pond disappears completely, killing every one of them in the process. Once the pond fills up in the winter, the tadpole shrimps hatch from their eggs, and grow at an impressive pace, reaching their adult stage in just a few weeks. Then, they reproduce, but the context of reproduction depends on the population. In some ponds tadpole shrimps reproduce sexually, but in many populations the males are absent, and the females reproduce asexually, in a process called parthenogenesis. They release unique, long-lasting eggs that can stay dormant for many years, buried in the dry soil. This way, they can “skip” several years of drought, during which ponds have tendency of evaporating too fast. When there is sufficient precipitation and the pond fills again with rainwater, some of these eggs hatch (others stay in further dormancy for the following years), and the cycle starts again.
I was very happy to find these lively creatures in my last visit to Israel and could not resist taking some photos of them for Meet Your Neighbours project.

Tadpole shrimp (Triops cancriformis) from central Israel. The shield-like carapace gives it the appearance of a small horseshoe crab.

Tadpole shrimp (Triops cancriformis) from central Israel. The shield-like carapace gives it the appearance of a small horseshoe crab.