Belize - Gil Wizen

Little Transformers: This dung beetle has had enough of this bullshit

One of the things I have been focused on in the past two years, which is partially responsible for the long silence on this blog, is sorting through the backlog of photos in my archive. This is possibly the biggest curse of digital photography; you end up with hundreds of photos from each trip that eventually accumulate and often remain untouched for years. I made it a mission of mine to start going over this material in 2019, and unfortunately I misjudged how long the whole process was going to take. The good news is that most of the work is behind me. What I loved about this task was discovering many forgotten photos, as well as some hidden gems. One such treasure is photographs of a small dung beetle I encountered one night in Belize in 2014. On the surface it doesn’t look very special but its appearance was strange enough for me to decide I should photograph it. I thought its curved hind limbs were a malformation, but back then I did not know what I know today.
Oh, past Gil. You were so naïve and cute. But I’m happy you took those photos.

Dung beetle (Deltochilum acropyge), frontal view. Toledo District, Belize

This seemingly innocent dung beetle is a member of Deltochilum, a large neotropical genus that contains over a hundred species. What is special about this beetle in particular, and the reason it is included in the Little Transformers post series, is that it’s technically not a dung beetle. Or to be more accurate, it does not feed on dung or animal feces.
Not anymore.
Because enough is enough.
And if you are reading this post in 2021, while the world is still dealing with a global pandemic, social issues, and the effects of climate change, this small beetle may very well represent our collective mood.

Life is hard when you have to do this all day. Dung beetle (Canthon quadriguttatus) rolling a ball of fresh dung in the Ecuadorian Amazon

Generally speaking, dung beetles are famous for feeding on animal feces, from which they obtain the nutrients they need. Some beetles feed directly on top or dig under the dung, while others compress the dung into a tight sphere to feed on later and roll it to their nesting spot away from other beetles. Despite the unappealing dietary habits, the competition for dung is fierce, and often several dung beetle species fight each other for a piece of the hot pie. You can probably imagine how such a competition can cause a selective pressure towards a dietary change in some dung beetles, together with suitable morphological adaptations. One example is dung beetles that shifted into feeding on rotting fruits, mushrooms, or even animal carcasses. Other beetles took it even further and moved to predation. The latter is not a simple shift and it is considered quite rare in the animal kingdom, as it requires some conditions to be met: the beetle must be able to consume and digest the prey, not to mention it must also be able to capture it.

In 2009, a study of the predatory habits of Deltochilum valgum was published. This species preys on millipedes in the rainforests of Peru. It was discovered in a survey by laying pitfall traps with different types of baits, some of which contained millipedes and attracted the Deltochilum valgum dung beetles. The millipedes were chosen as bait for the traps because beetles have been recorded feeding on dead millipedes or carrying live millipedes in the past.
But how does this species fulfill the conditions mentioned above? The choice of millipedes as prey may seem surprising. After all, many of them are poisonous or deploy chemical defenses, and usually predators avoid them. However, this is exactly what makes millipedes an unexploited resource for which there is much less competition compared to dung. In addition, millipedes are detritivores feeding on decomposing plants and mushrooms, and therefore have a large amount of organic material stored in their body that makes a great source of nutrients for the beetles. Accessible food source – check.
Next on the list is the actual hunting and killing of millipedes. This is made possible thanks to small structural changes that have occurred in the beetle’s head and hind tibiae. Instead of rolling dung balls, the hind legs have curved tibiae as an adaptation for catching and holding millipedes tightly against the beetle’s pygidium. This allows the beetle to drag the millipede to a spot where it can kill it. After taking over and dragging the prey, the beetle inserts its serrated head between the millipede’s front segments, decapitating its head. This action paralyzes the millipede completely so the beetle can start consuming its juicy insides, leaving behind only disintegrated parts of the prey’s exoskeleton at the end of the process. So far there is only one video record of Deltochilum valgum hunting a live millipede. I wish there were more but nevertheless, hunting strategy – check.

Dung beetle (Deltochilum acropyge), dorsal view. The curved hind tibiae are an adaptation for grasping millipedes.

Much has changed since that publication. It is now clear that not one, but several Deltochilum species prey on millipedes, and they are grouped together taxonomically. Most of the species in the group share the curved hind leg adaptation for manipulating the live millipede prey. Similarly to Deltochilum valgum, they were sampled by pitfall traps with millipede bait as well. If I worked my way through the key correctly, the beetle I photographed in Belize should be Deltochilum acropyge in the valgum group within subgenus Aganhyboma, which is recorded from several countries in Central America. It is important to note that we do not know much about the life cycle of these beetles. As of writing this post it remains unclear what the beetle larvae feed on, but I would not be surprised if they require millipede prey for the completion of their development, whether on its own or mixed with dung.

Deltochilum is not the only genus of dung beetle that has evolved to use millipedes as a food source. Sceliages dung beetles from Africa are attracted to freshly dead millipedes and their larvae feed on balls of crushed millipedes, collected and prepared by the mother. And in South America Canthon dung beetles have been observed to feed on injured live and dead millipedes, leafcutter ant queens (watch a video of this behavior here, narrated in Portuguese), as well as other live dung beetles (as can be seen in this amazing Facebook video by João Burini, or on his Instagram post).

I should also mention that only a handful of Deltochilum dung beetles are predators, and looks can be deceiving. As an interesting anecdote, here is one species that according to our current knowledge is not a predator.

Dung beetle (Deltochilum carinatum). Shaped like a dark knight.

Deltochilum carinatum, in my opinion, is one of the most striking species in the genus. There is something about this beetle that reminds me of TMNT’s Shredder. The sharp angles, clear cuts, and overall structure. As if this body shape was made to either cut through or lock onto something.

Dung beetle (Deltochilum carinatum), dorsal view

Dung beetle (Deltochilum carinatum). One of the most peculiar-looking dung beetles in the Ecuadorian Amazon

But, as evidence suggests, this is just an ordinary dung beetle that feeds normally on dung. Maybe this will change one day, when we discover more about its life cycle and interactions with other species. For now we should enjoy it for what it is – a cool looking dung beetle. Not as badass as its murderous cousins though.

UPDATE (23 Jul, 2021): Some new photos of Deltochilum dung beetles hunting millipedes have been shared on twitter, I recommend checking them out:

I was fortunate to witness this in the field. pic.twitter.com/QIHVCPtk4T

— Mountain meanderings (@Mountain_steps) July 23, 2021

Schizomids, the unstoppable arachnids

What if I told you that right under your nose there is an entire group of arachnids that hardly ever receives any attention? It contains many species and has a worldwide distribution, but you will not hear about them in the news or see them presented on mainstream media. A couple of months ago I gave a talk about minor arachnid orders (any arachnid that is not a spider, scorpion, mite or tick) at Nerd Nite Toronto, and while doing so it suddenly occurred to me that I have never written about shorttailed whip scorpions, or schizomids, on this blog. This is surprising, because it has been six years since I have encountered them in Belize, and I have been keeping a live captive colony of them all this time.

Schizomid or shorttailed whip scorpion (Belicenochrus peckorum) from the Footprint Cave, Belize

Members of order Schizomida are tiny soft-bodied arachnids that inhabit the top layer of soil in caves and under rocks. Some of them also live inside decomposing wood, and several species are myrmecophile, living in ant nests. In these humid habitats they actively search for their prey – tinier invertebrates. In fact we are not really sure what schizomids feed on in the wild, but records show that they will gladly take down Isopods, springtails, mites and other small arthropods. At first glance they look like a sac spider crawling on the ground. However, a closer inspection reveals that their body proportions are different from those of spiders.

Shorttailed whip scorpion (Belicenochrus pentalatus), a representative of the small arachnid order Schizomida. This species is found in rainforest habitat.

Their name comes from the structure of the cephalothorax, which is split into several plates unlike in any other arachnid. Schizomids also have no eyes, which means their perception of the world is mostly tactile- and chemical-based. Their front pair of legs evolved into a sensory organ that can smell and taste as well as provide information on what is lying in front of the arachnid. These legs are called antenniform legs and they are very similar to those found in other arachnids, like whip spiders, vinegaroons, palpigrades, and even some mites, all of which walk on six legs only. The schizomid pedipalps are sturdy and built for grabbing, assisting in prey capture. Interestingly, their hind legs are modified and look very similar to those of crickets, and indeed it is reported that some species can jump to safety when threatened.

Schizomids look like a strange spider with grabby hands and cricket legs!

The thick setae on the schizomid pedipalps are used for sensing as well as a catching basket for prey.

The schizomid fang-like mouthparts (chelicerae) are found under the pedipalps

Another important character of schizomids is their short tail or flagellum (as opposed to the long flagellum in other tailed arachnids like vinegaroons and palpigrades). The tail is used for sensing but in males it has a unique structure, and it is possible that it plays a role in courtship or mating. In fact male tails are so different from species to species, that they are often used as an identification character in taxonomy.

Male shorttailed whip scorpion (Belicenochrus peckorum). Note the modified tail or flagellum.

Female shorttailed whip scorpion (Belicenochrus peckorum) with a modest tail

The Schizomida order contains about 350 species globally, with new species still being discovered. There are two existing families; Most of the known species belong to Hubbardiidae, while some Southern North American species comprise the smaller family Protoschizomidae. As a group they are closely related to the vinegaroons (or whip scorpions), and might even share some of their chemical defense against predators – there are reports of at least two species secreting odorous compounds when disturbed.

I encountered schizomids during Bugshot Belize in 2013. Piotr Naskrecki noted that the caves in the area are home to a species of ricinulei (another fascinating group of arachnids that are on my bucket list) and we should keep our eyes open. So I did. Already in the first few meters into the Footprint Cave I found a new species of whip spider, that I would later describe and name Charinus reddelli. But I also found a small arachnid that I have never seen before. Since I have seen very few ricinulei in my life I asked Piotr if this was one. “No” he replied, “but this is something just as good”. It was Belicenochrus peckorum, one of two species of schizomids found in Belize. Later, while dissecting a decomposing log, I found the other species B. pentalatus, which is a little smaller. The latter is the species I am currently keeping in captivity, and it has been fascinating to observe and learn from.

Shorttailed whip scorpion (Belicenochrus pentalatus) lives inside decomposing wood

One of the surprising things about schizomids is their reproduction. When conditions are favorable, they reproduce sexually like most animals. However, in times of stress and when males are scarce, females can switch on an asexual reproductive mode and lay fertilized eggs that will hatch into clones of the mother. This is very similar to other arthropods like stick insects and aphids, but quite unusual for arachnids. This type of reproduction is called facultative parthenogenesis. In the Belizean species I have been keeping, males were never present. In fact I remember coming home with only one live female, and this female gave birth to the entire colony.

Shorttailed whip scorpion (Belicenochrus pentalatus), possibly a gravid female. Being small does not make them immune to parasites – this one is carrying a few mites.

Similarly to whip spiders and vinegaroons, the females lay their eggs in a sac that they carry until the babies hatch. In small species like B. pentalatus the sac contains only 5-6 eggs, but the eggs are relatively large, which means the hatching babies are born at a size that allows them to hunt small arthropods. Once hatched, the babies climb on the mother’s back and stay there for two weeks before dropping off and starting their independent lives. Brooding females are very skittish; they will drop the babies at any disturbance.

A baby shorttailed whip scorpion (Belicenochrus pentalatus) in ambush for prey

A baby shorttailed whip scorpion (Belicenochrus pentalatus). Believe it or not, this animal is only 1mm long.

A juvenile shorttailed whip scorpion (Belicenochrus pentalatus) fresh after molting. The green abdomen is only temporary; it takes a few hours for the yellow-brown pigments to set in.

One of my memories from the encounter with B. peckorum in Belize was a photo session in which Piotr and I were taking turns trying to photograph one of the males. After a good 30mins of chasing the animal at a close distance with the lens, Piotr looked at me frustrated and said it’s impossible. If you follow my posts here then you know that nothing is really impossible when it comes to photography if you are willing to invest the time in it, but I understood him completely. Schizomids are some of the most active arachnids out there, especially if they are exposed (as would be the case when photographing them). Very rarely have I seen them stop to rest. Add their minute size to this equation, and it becomes clear why photographing them can be extremely unrewarding. However with patience and perseverance, you can come up with some decent shots. I hope to encounter more species of schizomids in the future, with their wide distribution there is so much to discover.

Lyssomanes – the spider from the upside down

Out of all the different microhabitats plants provide for organisms, the living leaf is arguably the most underrated one. On the surface it seems that it pales in comparison to the rich leaf litter of the forest understory, or to the complex bark of trees that provide hiding and hunting spots for many animals. However, although the green leaf may look innocent, it in fact holds many stories of deception and survival. The upper surface of the leaf offers exposure to sunlight and water, as well as additional nutrients coming from above. It can serve as a solid base for the growth of ferns, mosses, lichens, and fungi. It can also be folded and glued to create a nest or shelter for an animal or its eggs. Not to mention that in many plants the entire leaf comprises of edible material available for herbivores. But there is another plane of existence, a much darker reality. It is located in a parallel dimension – an inverted copy of the leaf upper surface. This is the upside down world of the leaf underside. Many organisms live here; some only take shelter during the day and resume activity on the upside world at night, others prefer to feed under the leaf to avoid predators. But one of the most fascinating examples is a group of predators that learned to utilize the leafy upside down for ambushing prey. I have already written about two of those, and today I would like to present another member of this guild: Lyssomanes, the green jumping spider.

Green jumping spider (Lyssomanes sp.). The spider’s pale color helps it to blend in with the leaf it is sitting on.

At first glance Lyssomanes doesn’t look like a typical jumping spider. It has very long and slender legs, and prefers to move by running and using short leaps as opposed to the jumps that characterize most members of the salticid spider family. In addition, the spider is almost completely hairless, sporting a pale body color, usually (but not always) green, and occasionally semi-translucent. Unlike other jumping spiders, the only scales covering the body are clustered as a crown on its head. Those can be white, yellow, orange, red, or any combination of these colors, depending on the species and developmental stage. Sometimes dark banding is present on the legs, usually in adult males.

Green jumping spiders (Lyssomanes sp.) often have a glossy, semi-translucent body, with a crown of colorful scales on their head.

The genus Lyssomanes contains around 90 species, all distributed in the Americas. Many species have similar external appearance. The type species from which the genus was described is named Lyssomanes viridis (from Latin – green jumping spider), but if I want to be completely honest, almost every species I encounter looks ‘viridis’ to me. They are just so green!

Not all Lyssomanes jumping spiders are green. Some are lemon yellow like this species from Belize.

One of the most noticeable features of Lyssomanes jumping spiders is their enormous anterior median eyes. Because of the spider’s pale color, it is also very easy to observe the internal retinal movements as the spider angles and focuses its field of view. The eyes may appear black at times, or pale green, crossed, or alternating (here’s a fantastic video showing this, and watch what happens when an ant passes by!).

Green jumping spider (Lyssomanes sp.) staring straight back with its huge eyes. If you don’t think it is cute you might want to check your pulse.

Female Lyssomanes are very modest in their appearance. Males on the other hand, are impressive beasts with long pedipalps and elaborate chelicerae, often armed with thick setae and teeth. The latter are used in male fights for mates. Males also have extremely long legs, which they use for pushing an opponent and waving to females as a part of the courtship process.

Male Lyssomanes spiders have long legs and pedipalps for signalling conspecifics, and often sport impressive chelicerae for fighting other males.

Closeup on a male Lyssomanes spider. Notice the teeth on the long chelicera.

Portrait of a male green jumping spider (Lyssomanes sp.) with his long chelicerae

Similarly to other predatory dwellers of the leafy upside down, Lyssomanes spiders deploy an ingenious hunting technique. The spider’s huge eyes are a good indication of its hunting method – it uses its excellent vision to locate prey. Lyssomanes jumping spiders are diurnal sit-and-wait predators of dipterans and other soft-bodied arthropods. They prefer to sit on leaves that are exposed to the sun, waiting in ambush for a visitor on the upper surface to cast a dark shadow. If the shadow is of the right size and shape the spider will shoot itself from the underside to the upper leaf surface and snatch the unsuspecting prey.

Male green jumping spider (Lyssomanes sp.) ambushing prey on the underside of a leaf backlit by the sun

Occasionally, if sunlight is obstructed, the spider will explore the leaf and actively search for passing insects. It does not, however, stay loyal to one leaf. Once spotted, the spider usually does not take any chances and relocates to a nearby leaf.

Snap! When startled, the green jumping spider (Lyssomanes sp.) swiftly moves to the other side of the leaf.

Although jumping spiders rarely use silk for hunting, most of them build a small silky sleeping bag inside a crevice or a folded leaf for resting at night and molting. Lyssomanes is unique in that it does not construct such a shelter. Instead, it lines the underside of the leaf with a thin carpet of silk, and rests on it completely exposed.

Green jumping spider (Lyssomanes sp.) spinning silk on the underside of a leaf

Gravid females construct a similar web for their eggs. Passing insects often trample the sheet, which triggers a predation response from the spider.

Female green jumping spider (Lyssomanes sp.) protecting her eggs

Cannibalism is common in salticids. Here, a green jumping spider (Lyssomanes sp.) is preying on a smaller spider that happened to walk on its leaf.

Unfortunately, this habit of Lyssomanes to sit exposed also means that they are sitting ducks for other predators, usually other species of jumping spiders. Remember – it is a harsh world out there and it’s not easy being green!

The grass is not always greener on the other side of the fence – a green jumping spider (Lyssomanes sp.) has fallen prey to another jumping spider!

Little Transformers: Forcipomyia, the midge that turns into a balloon

It is time to introduce another Little Transformer! I know what you are thinking. Am I ever going to run out material for these blog posts? Maybe. Probably not. As long as there are arthropods around, their life history and morphological diversity guarantees that I will always find examples for interesting deceptions and transformations. Up until now I mostly focused on animals that can change form quickly, assuming the appearance of something else as a defense response against predators and to avoid detection. The case presented in this post is a little different because it does not follow a quick change of form, but rather a slow one, over the course of a life stage. I should be cautious here, because under this definition every insect that goes through complete metamorphosis from larva to adult can be considered a Little Transformer (butterflies, beetles etc’). Even amphibians fall under this loose definition. And to some extent they ARE transformers, because the changes they go through during development are extreme. But this is not the topic for this series of posts. When I talk about a big change happening within a life stage, I mean that the animal starts as one thing, and by the end of the stage its appearance and function has changed into something else completely. And no example is better to show this than the parasitic midges of the genus Forcipomyia.

Biting midge (Forcipomyia sp.) feeding on the hemolymph of a moth caterpillar. Photographed in Belize

Here is the Forcipomyia midge with the whole caterpillar to give a better sense of scale

Forcipomyia is a large genus in the midge family Ceratopogonidae, with a worldwide distribution and diverse habitat preferences. There are now over 1,000 described species of Forcipomyia. The adults of some species are known as important pollinators of cacao and other plants of economic importance in tropical and subtropical areas. However, many species in the genus are blood-feeders, somewhat characteristic to ceratopogonids as the common name to the family suggests (biting midges). These parasites have interesting relationships with different insect hosts, and they can be found feeding on the hemolymph (insect blood) of grasshoppers, katydids, stick insects, butterflies, true bugs, and even skittish dragonflies. In fact, these interactions are so fascinating and overlooked, that only after spending some time in the field one can notice the midges have a preference for certain host species to feed from.

Sometimes the biting midges sneak into the photo without me noticing. I photographed these mating grasshoppers (Cloephoracris festae), but they have an accompanying Forcipomyia. Can you spot it?

But let’s go back to the transformation they go through, because in one group of species, subgenus Microhelea, it is truly remarkable. The female Forcipomyia midge begins her adult stage with an active lifestyle. She flies about in the forest, feeding on nectar from small flowers. As days go by, she starts craving for blood and search for insects to bite. When she locates her preferred host, using her serrated mouthparts she proceeds to bite it in an area that has soft tissue: antennae, legs joints, wing veins, or between body segments. Once she found the right spot that will fulfill her dietary needs, the female midge attaches to it firmly, and… doesn’t let go, thanks to specialized claws on her feet. She sucks and gulps the insect’s blood, filtering the nutrients and secreting the excess fluids as clear droplets.

Tick fly (Forcipomyia sp.) feeding on the hemolymph of a walking stick

The midge stays attached like this for quite a while, and soon this sessile lifestyle starts taking its toll on the small parasite. She starts to put on weight. Then, she usually loses her wings – she will not need them anymore because the added mass from the developing eggs prevents her from taking off.

Female Forcipomyia swelling while feeding. She lost her wings but can still use her legs to hold firmly onto the host

Forcipomyia getting fatter… but not quite there yet

As she continues to swell like a grapefruit, the Forcipomyia midge also losses the ability to use her legs. She does not need to leave anyway, but she is so bloated that she cannot even hold onto the body of the host, and the only thing keeping the two connected are the midge’s mouthparts.

Female tick fly (Forcipomyia sp.) at the final stage of feeding. Her legs released their grip on the host and at this point the midge has fully transformed into a passive parasite that looks like a balloon.

Stick insect (Pseudophasma bispinosum) carrying tick flies (Forcipomyia sp.) at different stages of feeding. Photographed in Ecuador

At this point, the engorged biting midge is no different than a tick, and indeed many refer to these parasitic Forcipomyia as tick-flies. Sometimes I like to imagine these fat dipterans disconnecting from their host and floating upwards like a balloon filled with helium, reaching above the forest canopy and flying into space. In reality, the exact opposite happens. The Forcipomyia female eventually leaves the host and drops to the ground, where she lays her eggs and finishes her role. And the male Forcipomyia? They are mostly unknown. Because males are never found feeding on insect hosts, it is safe to assume that they do not feed on blood, and prefer to keep a vegan diet of sweet nectar.

An engorged female tick fly (Forcipomyia sp.) after dropping from its host

Tick fly (Forcipomyia sp.) engorged with hemolymph viewed from above

What about the larvae, are they parasites too? The majority of the research on biting midges has focused on the adults, due to their economic and medical significance, as well as their important role in aquatic ecosystems. Larvae of most ceratopogonids are unknown because finding them in their natural habitats can be challenging. They usually inhabit aquatic and semiaquatic habitats, but in the case of Forcipomyia the larvae are terrestrial and prefer to feed on moist detritus and organic matter under bark or in moss. In some species they feed on algae.

This stick insect is staring at me with tired eyes. I wonder if it is aware of the two hitchhikers it is carrying?

With so many aspects of their life history still unknown, and especially due to their ecological and economical importance, you would expect to see more active research on Forcipomyia. The bad news is that there is not enough research going on. A few years ago, I approached Dr. Stephen Marshall, a dipterologist from University of Guelph, and suggested doing a PhD study about Forcipomyia’s biology, phylogenetics, and their relationships with their hosts. I was politely refused, unfortunately. I still believe there is potential for a cool project involving Forcipomyia, maybe someone will pursue it in the future.

Little Transformers: Eburia pedestris

We are back to celebrate little transformers: insects that are more than meets the eye. In this post I feature an insect whose transformation may seem a little awkward at first. It is not of cryptic nature, and it is not a case of mimicry.

While doing research about whip spiders in Belize, I also surveyed the insect biodiversity of one site, and so made sure to visit the light traps that we set up in several spots. The traps attracted an impressive diversity of insects, including moths, leafhoppers, ants, mantids, and katydids. One night a beautiful longhorn beetle (family Cerambycidae) showed up at the light trap. I did not recognize it at first so I collected it for a short Meet Your Neighbours session.

Longhorn beetle (Eburia pedestris) from Belize

It was Eburia pedestris, a member in a genus of hardwood-boring longhorn beetles with a wide distribution in the Americas. I took a few decent shots. The beetle was trying to escape of course, so I reached out to grab it before it fell from the acrylic sheet. The moment I touched it something interesting happened. It crossed its legs and took a sitting position. I could not help it and I sneaked a loud laugh, because it looked like the beetle was in the middle of a yoga practice. It stayed in this comical position for a while, so I took some additional shots.

Longhorn beetle (Eburia pedestris) just sitting around

Another view of the strange pose taken by Eburia pedestris

The strange position did not make a lot of sense to me, but I thought maybe it was a more elaborate way of playing dead, a common behavior in many beetle families (which will probably be featured more than once in this series). I finally decided not to wait for the cerambycid to “open up” so I grabbed it in my hand to put it back into the vial before releasing it outside. And then it hit me.

I mean, it literally hit me.
I felt my hand being pierced in several spots. Blood was dripping from my fingers.
You see, there is a reason why Eburia beetles take this unusual body posture. Look at the beetle’s leg joints and at the tips of the elytra. By taking a “sitting” pose, the beetle transforms into a prickly business, pointing sharp spikes in all directions, making it difficult for large predators like myself to handle the beetle. It will also not hesitate to use its other cold weapon: biting mandibles. Something I only noticed much later when I examined the photos – notice how the beetle contracts its abdomen, to make the elytral spines more prominent. Even with caution it was difficult not to get your skin punctured by the spines. They are as sharp as syringes. I would not want to imagine the experience for a mammal trying to eat this beetle. Ouch.

Longhorn beetle (Eburia pedestris) in defense posture. Grab it if you can.

Some insects prove to us that avoiding predators is not all about hiding, mimicking other organisms, and advertising toxicity or potent venom. There are other, more creative ways to survive in the jungle out there. I will even take it a step further and say this Eburia beetle is comparable to the armadillo girdled lizard in its behavior. Nature is so awesome.

Little Transformers: Ceratocanthinae beetles

If you missed my subliminal message in the last two sentences of the previous post, I am not done yet with the Transformers. I was building up to this exact moment. You see, insecticons ARE everywhere. Maybe not in the same context as depicted on the TV series, but still there are creatures out there that are more than meets the eye. A substantial part of their existence relies on fooling predators into thinking they are something else: an inanimate object, another animal, or something completely different. I am happy to introduce “Little Transformers”, a new section on the blog, in which I will present interesting cases of insects in disguise.

We are launching this series with the beetle that started it all – the pill scarab (member of subfamily Ceratocanthinae). If you run an internet search with the words “transformer” and “insect”, there is a high chance that one of the results will be an image created by Kenji Nishida, showing a small beetle from Costa Rica transforming from a ball-mode to beetle-mode. The image has gone viral soon after being posted online, and now that Ceratocanthus beetle is fairly recognized by title as the beetle transformer. I have posted an image of a similar beetle before on this blog, a Ceratocanthus species I found in Belize. It was featured in an excellent phylogenetic paper about this subfamily by Alberto Ballerio and Vasily Grebennikov, and even made it to the journal’s cover. I recommend checking the paper out, even if you are not interested in these beetles, you can enjoy the beautiful images showing the impressive diversity of the group.

Pill scarab beetle (Ceratocanthus sp.) from Belize, showing the spherical alternative mode typical to members of Ceratocanthinae

Ceratocanthinae are a subfamily of Hybosoridae within the Scarabaeoidea beetle group, containing over 360 described species, most of which are small in size (just a few millimeters in length). They have a wide distribution range mainly in tropical regions throughout the world, with only a few genera and species recorded close to temperate regions. Ceratocanthinae also occupy different types of habitats. The highest diversity seems to be in new world rainforests, but they also occur in temperate forests, subtropical forests, savannahs, and even in coastal deserts. Adult Ceratocanthinae are best known for their ability to conglobate: rolling into a nearly perfect ball. The elytra, pronotum, head, and all six tibiae interlock with each other by means of grooves and corresponding ridges, forming a tightly connected external surface. Many beetles take the form of a tight compact structure when threatened, however in Ceratocanthinae the tibiae of all six legs participate in forming the external hard surface of the sphere, unlike in other beetles.

Ceratocanthus sp. transformation sequence from ball-mode to beetle-mode

It is fascinating to observe these beetles transform to and from their alternative mode. Nancy Miorelli, an entomologist and science communicator living in the Maquipucuna reserve in Ecuador, recently recorded a video showing the beetle opening up (by the way, Nancy also creates beautiful jewelry from insect wings and Tagua nut with the proceedings supporting rainforest conservation and the local community. You can check out her shop here).

Why do they do this? The ability to roll into a tight compact structure probably has anti-predatory and physiological advantages, such as moisture retention or thermoregulation. It seems that the primary use is as a form of crypsis, to avoid detection by nearby predators, however after following several beetles in the wild I noticed that they stay transformed into the ball-mode even when they are not active; perhaps it is a way for them to rest too.

Pill scarab beetle (Ceratocanthus sp.) from southern Belize. Full beetle-mode!

Unfortunately, very little is known about the biology of Ceratocanthinae. They are sometimes found under bark, in tree holes, and in decomposing wood. Several records report adults and larvae that have been found in termite nests. However, It is unclear whether Ceratocanthinae are termitophilous and have a relationship with the termite hosts. The ability to roll into a ball can serve as a defense and might be an adaptation for living in the hostile environment of a termite nest. Another suggestion defines the beetles as termitariophilous, in other words attracted to the properties of the termite nest itself as opposed to its inhabitants. While the feeding habits of Ceratocanthinae are mostly unknown, a handful of observations report adults feeding on various fungi. It is therefore possible that Ceratocanthinae are attracted to some of the fungi growing on the surface of termite nests. This can explain the presence of the beetles in the nests, but unfortunately without additional data about the beetles’ life history it would be difficult to validate this connection.

So the next time you are out in the field and you stumble upon a tiny sphere in a peculiar place, take a closer look. If it looks like a beetle mummy, then bingo! You have a Little Transformer. Now all you need to do is wait for it to open up… Patience. Lots of patience.

(Inter-)National Moth Week

When all that people talk about right now is going outdoors with their smartphones and tablets to play the current-trendy Pokémon Go, an augmented reality game of hunting fictional creatures, it seems appropriate to remind everyone that a similar “game” was already in existence centuries ago and still goes on today. It is called being a naturalist, and the rules are pretty simple – you just go out to search for, observe, and document everything that nature has to offer. I guess making people spend more time outside is a good thing nowadays, I just wish they were looking more around them instead of having their faces glued to mobile screens. Nevertheless, many players reported that while playing the game they stumbled upon “real life Pokémon”, in other words wild animals such as snakes, birds and even mammals. Several biologists on twitter decided to take a nice turn on this game and came up with the hashtags #PokeBlitz and #PokemonIRL, tagging and spreading facts about various wild animals, plants and fungi. It is a cool initiative that I hope will spread like fire, but in any case I wanted to use this opportunity to mention another similar event happening this month – National Moth Week.

Geometer moth (Rhodochlora brunneipalpis), Limón Province, Costa Rica

Green geometer moth (Rhodochlora brunneipalpis) from Limón Province, Costa Rica

National Moth Week is a citizen science project that sets out to increase public awareness and appreciation of moth biodiversity. It has been running continuously for 5 years, with the main event taking place on the full last week of July. During this week, moth enthusiasts set up light traps to attract moths and record the species found in their area. They are often joined by professional lepidopterists (scientists studying this insect order), who offer assistance in identifying moth species and wait for cool and unexpected discoveries. With the current accumulating evidence of dwindling insect populations, especially those of pollinators like Lepidoptera and Hymenoptera, this activity has huge importance. National Moth Week has become a global joint effort to record moth species, yet the project’s title remains “national” to emphasize the outreach activity on the local scale. Anyone can join and attract moths in the comfort of their own home, but many groups hold moth-watching events at public locations, attracting a large crowd of enthusiasts and curious people (you can attend an event close to you by searching in the event map).

Crambid moth (Desmia bajulalis), Mindo, Ecuador

Many Crambid moth species, like this Desmia bajulalis from Ecuador, have iridescent scales on their wings.

Setting up a light trap for moth watching is super easy. All you really need is a light source, and turning on the porch lights is probably the simplest way to attract moths. If you want to invest a little more, you can get a light bulb with some output in the UV range, as many moth species are attracted to this type of light. Many entomologists and insect enthusiasts use high-output mercury vapor bulbs because their spectral range seems to be more attractive for insects compared to other bulbs. Personally, I do not like these bulbs; they are very fragile, become extremely hot during operation and quite finicky to set up in remote locations. I use a compact version of a bulb that has a similar spectral distribution and get good results. My setup is built to be portable, so I now take my light trap almost anywhere I travel.

White witch moth (Thysania agrippina). Amazon Basin, Ecuador

Sometimes a light trap is not even needed for attracting moths. This gigantic white witch moth (Thysania agrippina) came to our bathroom lights in the Amazon rainforest, Ecuador.

The light trap I used at Caves Branch, Belize, attracted a nice variety of interesting moths, including members of genus Petrophila (mentioned previously on this blog).

Moths attracted to light trap, Mindo, Ecuador

Moths (and other insects) gathering around a light trap in Ecuador

Moth feeding on top of another moth's wing, Mindo, Ecuador

When it gets crowded at the trap interesting behaviors can be observed, like this small moth feeding on a bigger moth’s hemolymph.

Finally, if you want to be able to record the species coming to your trap, you will need a surface for them to rest on. The simplest way to do this is by stretching a white sheet behind the light source. The flying moths will come to the trap, bump into the sheet and cling onto it, allowing close observation and photography. Not only moths, but also other arthropods can end up coming to the light trap as well. And, if you are lucky, even amphibians and reptiles can show up to take advantage of the abundant food.
The best thing about setting up light trap is that you never know what will show up. It is not uncommon to encounter a species that you do not know, or even better, find something that is very rare.

Geometer moth (Eutomopepla rogenhoferi), Mindo, Ecuador

Geometer moth (Eutomopepla rogenhoferi) from Mindo, Ecuador

Giant silk moth (Rhescyntis hippodamia). Amazon Basin, Ecuador

Giant silk moth (Rhescyntis hippodamia), one of the heaviest and largest moth species found in the Amazon Basin of Ecuador.

Geometer moth (Opisthoxia uncinata), Limón Province, Costa Rica

Geometer moth (Opisthoxia uncinata), from Limón Province, Costa Rica. This is probably one of the most common species in Latin America, it showed up in every light trap I have set up so far.

Wasp-mimicking moth (Gymnelia sp.), Mindo, Ecuador

Do not forget to check the surroundings of the light trap for even more species! This wasp-mimicking moth (<Gymnelia sp.) from Ecuador was found resting on the wall a few meters from the trap.

White geometer moth, Limón Province, Costa Rica

Some moths remind me of common butterflies. For example, this moth from Costa Rica somewhat looks like Small White (Pieris rapae)…

Giant silk moth (Titaea tamerlan). Amazon Basin, Ecuador

Giant silk moth (Titaea tamerlan) from the Amazon rainforest of Ecuador

Green moth (Epidelia sp.), Caves Branch, Cayo District, Belize

Green moth (Epidelia sp.) from Belize

Even a silhouette can be interesting! Crambid moth from Mindo, Ecuador.

Owlet moth (Sosxestra grata). Caves Branch, Cayo District, Belize

Sosxestra grata has become one of the most iconic Latin American owlet moth species, thanks to an excellent photograph taken by Thomas Shahan in BugShot Belize.

Some of the nicest wing patterns are found on the smallest species, like this delicate Crambid moth from Mindo, Ecuador.

So go out, and enjoy this fun activity. Moth-watching is the new birding. In fact, it might even be better than birding. It requires much less effort and preparations. In addition, the diversity of moth species found in a limited area can be astounding compared to that of birds. There is so much out there to discover, you really just have to look.

New species of Charinus in Belize

I am happy to announce that our new paper, describing two new species of whip spiders (Amblypygi) from Belize, was recently published (the paper can be downloaded here). This culminates work that started in 2013, in collaboration with Gustavo Miranda and Alessandro Giupponi.

Charinus reddelli from Waterfall Cave, Cayo District, Belize

The new species were found during the BugShot Belize workshop at Caves Branch Jungle Lodge and its surroundings. The smaller species of the two, now named Charinus belizensis, was discovered under a fallen log during a night hike, concealed inside the decomposing wood and sharing the space with Diplocentrus maya scorpions and platydesmid millepedes. The second species was found within several nearby cave systems, hiding under stones and running on the sandy bottom of the cave. As soon as I found these whip spiders I knew I had something that probably no one has seen before. These were new, undescribed species. Charinus species have been described from almost every continent, they are well-recorded in South America, but so far no species have been described from Central America. Only two reports mention presence of the genus Charinus in Central America: one report from Panama mentions an epigean species with well-developed eyes. I knew the Charinus that I found were different species due to their “blindness” – the two new species have no median eyes, an adaptation for life in closed dark spaces, such as caves and deep crevices. The other report from 1982 is by James Reddell, mentioning a whip spider “troglobite of uncertain generic affinities” in the Footprint Cave in Belize, probably the same species that I found in the very same cave, three decades later. We therefore decided to pay tribute to James Reddell for this discovery and for his enormous contribution to the study of the arachnids by naming this new species after him: Charinus reddelli.

The entrance to Waterfall Cave, where specimens of the new species C. reddelli have been found.

Charinus reddelli, a freshly molted specimen besides its molt in Waterfall Cave

It is not surprising that these species have not received any attention up until now. To begin with, they are very small. The leg span of the bigger species, C. reddelli, is just over 2.5cm. They constantly take shelter inside decomposing wood (C. belizensis) or in rock crevices in caves (C. reddelli). Also, to the untrained eye they may appear as juveniles of the much bigger Amblypygi genera found in the same area, Paraphrynus and Phrynus. As such small arachnids, one might wonder what they feed on. It is possible that C. belizensis feeds on termites and other soft arthropods found inside the wood cavity, whereas C. reddelli was observed feeding on cave crickets nymphs and was even spotted taking down another arachnid – a cave schizomid. Moreover, the live specimens that I keep in captivity have been found to be very fond of eating isopods, so it is possible that they are an important component in these species’ diet. Another interesting observation relates to their breeding strategy. Whip spider females are excellent mothers and demonstrate a high level of maternal care, carrying and protecting the eggs and then later carrying the hatched babies for a while until they can fend for themselves. As small-sized arachnids, Charinus species confront a problem. If they go the same path as the other whip spider genera, producing several dozens of tiny offsprings, then they might run into survival challenges, as the tiny babies must track down and hunt for even smaller prey, and at the same time deal with predators. Instead, C. reddelli‘s egg sac contains only 4–10 eggs, and the hatching whip spider babies are quite large. This ensures that the offspring have a slightly better start in life as they can exploit the common prey size in their surroundings.

Whip spiders females are good mothers and Charinus reddelli is no exception. Here, a female carrying her newborn baby on her back. Three other babies are still in the process of hatching under the mother’s abdomen.

Charinus belizensis fresh after molting before pigmentation appears. Found under a fallen log in Caves Branch forest.

It took a long process to obtain the proper permits, collect, export, and describe the new species, in which I received tremendous help from Ella Baron from Caves Branch Jungle Lodge. The important thing is that now these two small arachnids are known, they have a name and a valid presence, which will make it easier to protect them and their habitat. I hope that in the near future more species of Charinus will be discovered in Central America, filling the gap in their known distribution.

Teenage Mutant Ninja Orchid Bees

Whenever I visit Latin America I make sure to leave some time for observing orchid bees in activity. This means my morning routine is usually very brief: a quick breakfast, some reorganization of gear from the previous night hike, and heading out. The bees are usually active between 7:30-11am, so it is a race against the clock to locate them in the rainforest.

A month ago I posted a photo on my social media accounts showing a group of Euglossa bees collecting fungus threads from tree bark in Costa Rica. Since then, this photo has become very popular and has been shared and retweeted thousands of times (unfortunately, a big chunk of these shares is by people who uploaded the photo to their pages without my permission). This is currently my most shared photo to date. Even as of writing this post, one month after posting the photo, it still generates new likes, shares, and comments. In fact, the title of this post, “Teenage Mutant Ninja Orchid Bees”, is taken directly from the comments, as some people noted the photo reminded them of Teenage Mutant Ninja Turtles.

A group of colorful orchid bees (Euglossa hansoni, E. sapphirina and E. tridentata) collecting fungus filaments from tree bark, Limón Province, Costa Rica

While I will argue that in order to truly appreciate the beauty of orchid bees one must observe them from a close distance, this photo does represent well their diversity (showing three distinct Euglossa species) and variation (the “red” and “orange” bees belong to the same species). Soon after the photo spread through the internet I was flooded with questions about orchid bees, so I thought it would make a nice opportunity to write a post about them and address some of the inquiries.

That orange bee (Euglossa hansoni) from the group photo above? This is what it looks like when viewed from up close. Words cannot describe this beauty.

Are you sure these are not flies? Despite bearing a strong resemblance to bottle flies, these insects are indeed bees: orchid bees are members of tribe Euglossini which contains five genera: Euglossa, Eulaema, Eufriesea, Exaerete and Aglae. They are somewhat closely related to the eusocial honey bees and bumblebees, however most orchid bees lead a solitary lifestyle. The genera Exaerete and Aglae are cleptoparasites, developing in the nests of other orchid bees. There are about 200 species of orchid bees, distributed only in the Americas, mostly in Central and South America. Only one species occurs in the United States. Like many other bees, orchid bees collect nectar, pollen and resin from plants. They can be distinguished from other bees by their shiny metallic coloration and their extremely long tongues, which can be twice the length of the body. Most of the time the tongue is folded underneath the body and extends behind the abdomen.

Orchid bees can be easily found near fragrant orchids. This male was spotted hovering near a vanilla flower. Photographed in Caves Branch, Cayo District, Belize

Male orchid bee (Euglossa sp.) collecting resin from tree bark. Photographed in Toledo District, Belize

Are they dangerous? Can they sting? Orchid bees are far less dangerous than honey bees. Being solitary (excluding a few species that are communal), orchid bees have no colony or a queen to defend. That being said, female orchid bees do possess a stinger, which they will not hesitate to use when threatened. Interestingly, the females are very rarely encountered. I have encountered them only near stream banks, collecting clay mud for construction of their nest. Most of the bees observed in the rainforest are males. Although their folded tongue sticking behind the abdomen may look like a stinger, males have no stinger and pose no danger to anyone.

Male orchid bee (Euglossa sp.) in mid-flight, showing its long tonguefolded underneath the body. This is not a stinger! Photographed in the Amazon Basin, Ecuador

Why are they called orchid bees? Male orchid bees exhibit an interesting and unique behavior – fragrance collection. They collect and store different volatile compounds, some of which are found in orchid flowers. To get the right mixture of chemicals, they sometimes travel long distances in flight. Being able to detect the tiniest amount of a desired compound in the air, the bees home-in on the scent column and navigate to it with impressive accuracy. Once landed at the site, the males scrape the odorous compounds using modified brushes on their forelegs, and then while in mid-air transfer and press them into special storage chambers in their hind legs. The process is repeated until the bee has collected enough of the chemical. The purpose of collecting the fragrant compounds is not entirely clear, but it is strongly believed that they play an important role in mate choice by the females, just as perfume is used to attract a mate in humans.

Male orchid bee (Euglossa intersecta) collecting fragrant compounds from tree bark. Note the long hairs on the forelegs that assist in scraping the chemicals. Photographed in the Amazon Basin, Ecuador

Male orchid bee (Euglossa sp.) collecting fragrant compounds from tree bark. The chemicals are stored in special chambers located in hind tibia. Photographed in the Amazon Basin, Ecuador

To collect a variety of scents, the bees visit primarily orchids flowers, but also other flowers, tree wounds, fungi and even corpses. One species was even recorded collecting the insecticide DDT without suffering any damage from the chemical.
The fragrance collection behavior allows the attraction of males using different baits containing essential oils, and can be useful for biologists to learn about their seasonal abundance and diversity.

A carefully selected site for baiting orchid bees can attract a few dozens of males, as seen here. Photographed in Cayo District, Belize

Some fragrant orchids have evolved different adaptations to take advantage of this perfume-seeking behavior, which involve the male bees pushing or crawling into the flowers, triggering a mechanism that glues a pair of pollen packets (called pollinia or pollinaria, depending on the type of plant tissue involved) on the bee’s head or thorax. These pollen packets will travel with the male bee to the next flower to complete the pollination process.

Male orchid bee (Euglossa cyanura) pollinating the orchid Gongora maculata. Note the pollen packets glued on the bee’s back. Photographed in Toledo District, Belize

Why are orchid bees so colorful? This question is a hard one to answer. The metallic color does not seem to have a clear function. However, it is important to note that not all orchid bees are colorful. While members of genera Euglossa, Exaerete and Aglae are flashy with colors ranging from gold, red and green to blue and violet, members of Eulaema and Eufriesea are less showy and sport dark colors and a thick coat of hairs, which make them look like fuzzy bumblebees.

Representatives of three Euglossini genera, left to right: Eulaema seabrai, Euglossa intersecta and Exaerete smaragdina.

Orchid bees are fascinating insects that can be observed safely without the need for special equipment or prior preparation. I would like to share with you something I like to do when I find a group of male bees in activity: I approach slowly and place my head close to their gathering spot. The bees are so busy closing in on the scent cone that they are not bothered by my presence. Then I close my eyes. The loud buzzing sounds piercing through the air make me feel like I am standing right in the middle of an insectopian highway. It is quite a unique sensation. Try it. You won’t regret.

Good times to celebrate the diversity of Amblypygi

For as long as I can remember, I have been fascinated by arachnids. Their high diversity, which includes a variety of morphological and behavioral adaptations, is impressive. It might be surprising though that my favorite arachnid group is not spiders, but a relatively small and not-so-diverse order: whip spiders (Amblypygi).

Juvenile Heterophrynus batesii from the Amazon rainforest in Ecuador. The bright coloration and cute proportions fade as the amblypygid grows older.

I find it amusing that despite my obsession with Amblypygi, I have not yet written anything about them. This website had a gallery of whip spider photos since day one, but I guess I have been waiting for a good opportunity to mention them on the blog, and there is no better time than right now. A recent publication by my colleagues, describing eight new species of whip spiders found in Brazil, has given this group the much-deserved public attention.

Charinus is a genus of relatively small-sized whip spiders with a worldwide distribution. New species are discovered almost annually (the species described in the above mentioned paper are all members of this genus). This one is another new species from Belize soon to be formally described.

Despite their common name (see footnote †) and general appearance, whip spiders are very different from spiders. They cannot spin silk and therefore have no webs. Their first pair of legs has evolved into long, antennae-like sensory organs, which are used for navigation, detection and manipulation of prey, and social communication. It is ironic that what makes whip spiders so visually appealing to some people (myself included), is the same thing that makes them terrifying for other people: the raptorial pedipalps. Enlarged and armed with strong spines, the pedipalps are used as a catching basket for grabbing and impaling prey. They are also used in mating and fighting rituals. The long, spiny “grabbers” make many people cringe in fear at the sight of a whip spider. But make no mistake: these animals are completely harmless to us. They do not have venom, they cannot sting and never bite, and they will do whatever they can to avoid confrontation with a human. It is therefore unfortunate that whip spiders are often if not always used to provoke feelings of fear and disgust, as seen in TV programs such as “Fear Factor” and movies like “Harry Potter” (see footnote ‡).

Adult male Heterophrynus batesii with impressive pedipalp armature. This is the same species shown in the first photo above.

Paraphrynus raptator feeding on an assassin bug. The spiny pedipalps are used to impale the prey and bring it closer to the mouth.

For a shy animal, whip spiders sure pack a lot of character. This is something I will address in several future posts. But newly discovered species of whip spiders are always a cause for a celebration. The new paper puts Brazil in competition with Mexico for the title ‘Country with the highest diversity of Amblypygi’ (Brazil wins. For now). One of the possible explanations for the high diversity is the large continental area within the borders of each country, following a classic principle in Ecology that says species richness increases with area. Under the same principle, the smaller neighboring countries are expected to have less species, and this is indeed what we are seeing. Or is it? There might be another reason involved. Because the small order Amblypygi is of no economical and medical importance it is often understudied, so it is very possible that the low amblypygid diversity seen in other countries reflects a lack of research or difficulties in sampling. A similar trend can be found for other groups of organisms sharing the same attributes. It all points to a problem: basic natural history and taxonomic research is becoming less common and receives fewer support, while our conservation efforts aim higher every year. This creates a conflict – how can you protect something if you do not know about its existence? And indeed, the authors of the paper discuss the issue of conservation. The newly discovered whip spiders may already be endangered due to habitat destruction by humans. Nevertheless, their formal description gives them a valid status, and together with other native plants and animals in need of protection, this serves as an incentive for conservation of their natural habitat.

Juvenile Phrynus parvulus found on a moss-covered tree trunk in southern Belize

† There is a bit of a confusion around the common name for Amblypygi, as several different names exist. I prefer to call them amblypygids, referring to the scientific name of the group, but if I am forced to use a common name I go with whip spiders. One other frequently used common name is tailless-whip scorpions, which refers to their tailed relatives, the whip scorpions or vinegaroons, members of order Thelyphonida (formerly Uropygi). I completely disagree with the use of tailless whip scorpions as a name for Amblypygi. A large taxonomic group cannot be defined by something it does not have, unless this character is found by default in all other related groups. If you disagree, please consider why humans are not called “tailless monkeys”.

‡ One example in particular that I find infuriating is a series of videos recently turned viral, showing a person literally abusing whip spiders to the point that the animal has no choice but to attack using its pedipalps. Because of my deep interest in amblypygids these sickening videos have been forwarded to me multiple times by friends who thought I might like them. Interestingly, the person who made these videos actually loves arthropods, yet he seems to be unaware that his videos are spreading hate and misinformation towards these remarkable arachnids, not to mention the pointless abuse and stress of wild-caught animals (I have never gone after someone with the goal of publicly shaming them and will not mention any names; those who have seen the videos know the guy and what I am talking about).

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