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Rhynchotermes – the best of both worlds

If you read my previous post about blattodeans you might have noticed that I left something out. The post does not make a single mention of termites that belong in the same insect order. Yet my Blattodea gallery contains photos of some termite species. What is going on?

Make no mistake – termites are indeed included in order Blattodea. While they do not lay their eggs in cases (oothecae), they share many other attributes with roaches. Historically, termites were classified under their own order, Isoptera. This is what I learned at university during my entomology training a decade ago. However, times change, and with it taxonomy is rearranged according to new evidence concerning the relationships between groups. Termites have been found similar in their morphology and social behavior, as well as molecular phylogenetics, to wood-feeding roaches of the genus Cryptocercus, and both are now treated as sister groups under the infraorder Isoptera within the Blattodea. I will only say that although I welcome this update in termites’ taxonomical position, I found it difficult to get used to at first. Old habits die hard I guess.

Termites are truly unique because they are among the few hemimetabolous insects (lacking the pupal stage in their life cycle) to develop an eusocial lifestyle, with different reproductive castes, division of labor, and overlapping generations. In stark contrast to eusocial Hymenoptera (ants, bees, and wasps), termite colonies follow a different structure, often with a single long-lived royal pair responsible for egg production (as opposed to male Hymenoptera that die soon after mating), but also include a secondary reproductive caste. Workers and soldiers can be both males and females (in Hymenoptera – all females). From an ecosystem standpoint, termites play a vital role as detrivores, feeding on and breaking down dead plant tissue and wood. For this reason they rely on gut symbionts (protozoans, bacteria, and flagellates) that assist in breaking down cellulose.

One of the things you often learn about termites in an entomology course is that there are two types, easily distinguished by their soldiers: species with mandibulate soldiers (possessing jaws), and species with nasute soldiers (with a long nose). The mandibulate soldiers use their enlarged strong mandibles to physically attack and injure intruders. They cannot use their jaws for feeding, and are therefore dependent on mouth-to-mouth feeding from the workers. In contrast, the nasutes deploy chemical defense by secreting various compounds from their nose, mainly to use as deterrents against ants, but also with some effect over much larger predators such as tamanduas.

Why this long introduction? As things usually go in nature, and more specifically in arthropods, to every rule there is an exception. Last year I travelled to Costa Rica, and one of the species I was hoping to find was a very unique termite.

Armed nasute termite soldier (Rhynchotermes perarmatus)

Armed nasute termite soldier (Rhynchotermes perarmatus)

This monstrous beast is a soldier of Rhynchotermes perarmatus, a nasutiform termite. However, contrary to the “rule” I mentioned above, soldiers of this species possess both a chemically armed snout and well developed mandibles. They are now treated by taxonomists as being mandibulate nasute.

The neotropical genus Rhynchotermes contains several species, all have nasute soldiers with noticeable mandibles. However, only in two species the mandibles are massive – Rhynchotermes perarmatus and R. bulbinasus.

Armed nasute termite soldier (Rhynchotermes perarmatus). Combining elements from both nasute and mandibulate termites!

Armed nasute termite soldier (Rhynchotermes perarmatus). Combining elements from both nasute and mandibulate termites!

Rhynchotermes perarmatus is subterranean, nesting underground or under stones. These termites usually do not expose themselves to the outside world, but instead move inside covered tunnels constructed from soil particles. Inside these dark tunnels the stout workers run clumsily, carrying debris and compressed wood fiber back to the colony for food.

An intimate look at Rhynchotermes perarmatus termites crawling in one of their covered nest tunnels

An intimate look at Rhynchotermes perarmatus termites crawling in one of their covered nest tunnels

An active tunnel contains a thick flow of worker termites, and several soldiers scattered at the periphery, on guard.

An active tunnel contains a thick flow of worker termites, and several soldiers scattered at the periphery, on guard.

Rhynchotermes seems to be associated with slightly disturbed habitats, such as cleared forest areas or meadows used for cattle grazing. There are reposts of them active under aged dried out cattle dung, suggesting they may have a role in breaking it down and recycling the nutrients. In Costa Rica I found Rhynchotermes perarmatus under a heavily decomposed fallen tree, right besides a well-maintained trail. Still, after flipping the log I could not see them. I had to break open one of the galleries to get access to the action.
And the soldiers did not like that.

Armed nasute termite soldiers (Rhynchotermes perarmatus) crawling out to defend the workers

Armed nasute termite soldiers (Rhynchotermes perarmatus) crawling out to defend the workers

While the workers kept on running seemingly undisturbed, the armed soldiers started pouring out, seeking the intruder. Maybe this is the time to mention that termite soldiers are usually blind. They have no functional eyes, and rely on chemical cues and physical proximity for defending the colony.

"Fear me, ant!"

“Fear me, ant!”

Even tough beetles like this weevil know to steer clear of active Rhynchotermes perarmatus soldiers.

Even tough beetles like this weevil know to steer clear of active Rhynchotermes perarmatus soldiers.

To the human eye it seems like despite their menacing appearance, Rhynchotermes perarmatus soldiers do not do much. They walk around aimlessly, then suddenly rise on their feet and give a mute roar, gaping their mandibles. But what seems harmless to us is actually a well thought of strategy: the soldier’s head contains a special gland that secretes a cocktail of sticky odorous compounds from an opening located in the snout. It is easy to think of nasute soldiers as nozzle heads discharging glue, but in reality what Rhynchotermes discharge is a strand, not fluid. The idea behind this is to turn your enemy into a sticky mess and incapacitate it. This is effective in case of attacking ants, perhaps termites’ worst enemies. The chemical properties of the compounds may also have a role in disrupting the ants’ chemical communication. Sometimes during the interaction the termite soldiers stick to the ants as well, sacrificing themselves for the benefit of the colony. But what if this does not work? Then they can use their secondary weapon – the mandibles.

Armed nasute termite soldier (Rhynchotermes perarmatus) gaping its impressive mandibles

Armed nasute termite soldier (Rhynchotermes perarmatus) gaping its impressive mandibles.

The mandibles are curved (similar to those found in army ant soldiers) and double-hooked. I cannot help seeing them as reminiscent to the mandibles of young Epomis larvae. This is probably an adaptation to grab and hold on tight to whatever the termite is biting. I even tested it – not only the soldiers grab well, they also lock themselves in place. They are difficult to pull out, like a fishhook.

Let me tell you, these tiny soldiers can sure bite!

Let me tell you, these tiny soldiers can sure bite!

Another thing I noticed is that many soldiers had “broken noses”. I wonder if the snout has a breaking point to allow for a quick release of the gland’s contents onto the intruder. They too moved about clumsily looking for troublemakers to the colony, reminding me of a drunken guy trying pick a fight in a bar, broken bottle in hand.

Poor soldier got its nose broken

Poor soldier got its nose broken

Aren't these termites just stunning?

Aren’t these termites just stunning?

There is still much we do not know about Rhynchotermes. For example, in the case of Rhynchotermes perarmatus, the alate caste was described only recently. Some Rhynchotermes species tend to occupy abandoned nests of other termites, but occasionally they are also found in close proximity to active nests, bordering the neighbouring colony or right on top of it. It would be interesting to examine what kind of interaction they have with other termite species. Like a lot of things in nature, these termites do not conform to our neat labels. Their bizarre soldiers represent the best of both worlds. They serve as a reminder that nature is full of surprises, that rules are meant to be broken, and that you do not have to look hard to find something new and inspiring.

Cruziohyla calcarifer – closing the circle

Over three years have passed since my unforgettable encounter with the fringe tree frog, Cruziohyla craspedopus, in the Amazon rainforest of Ecuador. That experience is still one of my all-time favorite moments of working in the field. Since then, I learned a lot about this species and nowadays I see them every time I visit Ecuador (as you can probably tell by their growing presence in my frogs gallery). Still, even after all this time the fringe tree frog remains high up on my list of the world’s most beautiful tree frogs. But it felt like something was missing. I decided to take a trip to Costa Rica, and right from the start I had one goal in mind: to find the other half of genus Cruziohyla – the splendid leaf frog, Cruziohyla calcarifer.

Splendid leaf frog (Cruziohyla calcarifer)

Splendid leaf frog (Cruziohyla calcarifer)

After researching a little on C. calcarifer’s distribution, I decided to contact the place that in my mind packed the best potential of seeing one. The Costa Rican Amphibian Research Center (neatly abbreviated C.R.A.R.C.!) is a small biological research station located close to the Siquirres River in the Guayacán rainforest reserve, in Limón Province. It is owned and run by Brian Kubicki, a conservation naturalist who dedicated his life to the study of Costa Rican amphibians, with special focus on glass frogs, poison frogs, tree frogs and lungless salamanders. I thought if there is one person that can help me find C. calcarifer in Costa Rica, it must be him. Remember the frog poster from 2003 that I mentioned in the beginning of my post about C. craspedopus? Brian Kubicki was the person signed at the bottom of that poster. Now how cool is that.

To begin with, the C.R.A.R.C. Guayacán reserve is stunning. There are many interesting corners with different types of microhabitats, so a huge potential for finding interesting reptiles and amphibians, not to mention arthropods. Unfortunately for me, I arrived to the reserve during a dry spell, as it has not rained for days prior my arrival, and most habitats that were not directly connected to natural springs or the river were fairly dry. Even so, I still found the place highly biodiveresed, and recorded many interesting species of arthropods, some of which I have not yet had the chance to see in the wild.

Alas, I was there to find C. calcarifer, and I was worried that the area might have been too dry. Brain kindly offered to hike with me at night and show me some good spots to find specific amphibians. And it did not take him long; once we hit a certain trail he found C. calcarifer within minutes! What a gorgeous species. I will just paste here my description of C. calcarifer from the post about its sister species:

“…a massive tree frog, with eye-catching coloration: dark green (dorsal) and bright orange (ventral). The sides of its body are finely striped in black against an orange background. Its eyes, featuring a vertical pupil – an indication this animal has a nocturnal lifestyle, are orange with a grey center. In addition, the foot-webbing is wide and the adhesion discs on the fingers are large and round, giving it a cutesy appearance.”

Isn't it gorgeous? It is hard not to fall in love with these tree frogs.

Isn’t it gorgeous? It is hard not to fall in love with these tree frogs.

This tree frog species is indeed, as its common name suggests, splendid. It was exactly what I expected. The frog we found was a female, and I was surprised how robust it was. It is not every day you get to see an amphibian that is both colorful and big.

Cruziohyla calcarifer. So adorable and quite a hefty frog

Cruziohyla calcarifer. So adorable and quite a hefty frog

As mentioned, we found the frog at night. However, I wanted to see if I can locate it myself so I went back to the same spot in the morning. Let me tell you, it was not easy to find it in daylight. Not only it is difficult to find a green frog in the “sea of green” which is the rainforest, but also the tree frog is hunkered down and blends perfectly with the leaf it is resting on. After some time searching I thought about giving up, but then I looked up. I saw the perfect silhouette of a resting frog on one of the palm leaves, backlit by the sunrays penetrating the rainforest canopy. This could have still been an optical illusion created by a fallen leaf casting the silhouette. Yet, it was indeed C. calcarifer. I couldn’t be happier.

Splendid leaf frog (Cruziohyla calcarifer) in its rainforest habitat

Splendid leaf frog (Cruziohyla calcarifer) in its rainforest habitat

Cruziohyla calcarifer is a good climber and spends most of its time in the canopy

Cruziohyla calcarifer is a good climber and spends most of its time in the canopy

Splendid leaf frog (Cruziohyla calcarifer) showing off its beautiful stripy coloration

Splendid leaf frog (Cruziohyla calcarifer) showing off its beautiful stripy coloration

To me, seeing Cruziohyla calcarifer in the wild is a way to close a circle on a journey that started over a decade ago in a backpacker’s hostel in Costa Rica, continued in the Amazon rainforests of Ecuador, and ended in Costa Rica again.

Splendid leaf frog (Cruziohyla calcarifer) and fringe tree frog (Cruziohyla craspedopus). I wish moments like this one were possible in real life. Unfortunately, such a gathering of the two species is impossible. Even though both Cruziohyla species occur in Ecuador, they are separated by the Andes Mountains. C. calcarifer occupies the northwestern slopes, while C. craspedopus is found in Amazonian lowlands on the eastern side.

Splendid leaf frog (Cruziohyla calcarifer) and fringe tree frog (Cruziohyla craspedopus). I wish moments like this one were possible in real life. Unfortunately, such a gathering of the two species is impossible. Even though both Cruziohyla species occur in Ecuador, they are separated by the Andes Mountains. C. calcarifer occupies the northwestern slopes, while C. craspedopus is found in Amazonian lowlands on the eastern side.

This leaf got me thinking

I sometimes like to drift away in my thoughts and reflect on my days before becoming a biologist. It is amazing to realize how much I have learned over the years. This is something I think many people take for granted nowadays. We are flooded with easily accessible information on a daily basis. Try to think how many new things you learned just in the last month.
A little over a decade ago, I embarked on my first big overseas trip. Back then I knew close to nothing about Latin America. I had one goal in mind: to see poison dart frogs in the wild. Not too long into the trip I already felt victorious, after spotting some of these frogs in Bolivia and Ecuador. My quest took me to Costa Rica, where I found more of these stunning hopping jewels. Although I was mainly interested in amphibians, I was overwhelmed by the richness and diversity of arthropods. And more interestingly, despite my knowledge and exposure to various insect species, I realized how much I do not know and need to learn.

One such moment occurred when I visited the pastoral town of Monteverde, more specifically the butterfly gardens there. The guided tour I took passed near a moth wall, which was basically a white painted wall with a powerful light source pointing at it during nighttime. This was the first time I have ever seen a light trap. It was packed with hundreds of moth species. I was fascinated. The other visitors – not so much. They were pressing me to leave these “boring brown bugs” so we can head over to the butterflies area. “Just a second” I replied, “there is one moth I have to photograph”.

Leaf-mimicking moth, Monteverde, Costa Rica

Leaf-mimicking moth, from Monteverde, Costa Rica. Amazing camouflage, down to the level of leaf (=wing) damage and asymmetry. Image scanned from an old film slide.

“That’s not a moth” argued one of the visitors, “it’s just a fallen leaf that was blown onto the screen door”.
The local tour guide smiled but kept his silence.
“Well, if it is just a leaf…” I said and stood up, “…why don’t you touch it then?”
Upon being touched, the “leaf” immediately came into life and took off in a slow flight, disappearing into the foliage.

Many insects try to look like leaves. It is one of the most common types of crypsis. Only some of these insects, however, take it to the next level, mimicking not only the shape and color of leaves, but also their texture, tissue damage and even asymmetry. This moth had all of these. For years I have been waiting for an opportunity to photograph such a moth again, and finally, last year, I stumbled upon a similarly impressive species in the Amazon basin of Ecuador.

Leaf-mimicking saturniid moth (Homoeopteryx sumacensis), Amazon Basin, Ecuador

Leaf-mimicking saturniid moth (Homoeopteryx sumacensis) from the Amazon Basin, Ecuador. It was resting on the bathroom floor – I do not think I would be able to see it if it was resting among fallen leaves.

This species does look (and behave) very much like a leaf. Instead of laying flat like most moths, it holds its wings up in a way that creates a three-dimensional appearance. The forewing tips and margins are delicate; they are usually the first part to suffer tears and damage, contributing to the asymmetrical look of the false leaf. I knew immediately that I want to keep this photo for something special, and I decided to share it on the last day of National Moth Week. After posting it, the internet went wild. The photo was shared hundreds of times on social media, sparking discussions about evolution and moth diversity. It encouraged people to post their own photos of cryptic moths; others messaged me that the photo helped them to see the beauty and uniqueness of moths. I could not be happier.

Leaf-mimicking saturniid moth (Homoeopteryx sumacensis), Amazon Basin, Ecuador

From this angle it is easier to see that it is a moth. Leaf-mimicking saturniid moth (Homoeopteryx sumacensis)

It is important to remember though, that this moth is just one small example from a vast world of moths. There are over 150,000 species of moths worldwide, many undescribed, and many more waiting to be discovered. Moths are everywhere. There is more to them than meets the eye. They take many forms, and can sometimes make you doubt yourself. Until that moment in Costa Rica I was not aware these leaf moths existed, and even today I am not certain of their exact species ID*. Even nowadays within the highway of free information, I still have a lot to learn.

The positive feedback this photo received, as well as my orchid bees photo, made me realize also how much I am grateful for all the people who find my content interesting or inspiring. I never mention this, but it gives me a lot of energy. When things get rough, I remind myself that there is at least someone out there who thinks what I do is cool. I want to take this opportunity to thank all my followers, commenters and visitors. I got to know some fascinating people since I started posting. Thank you, everyone.

*UPDATE: This moth has been identified by Vazrick Nazari from the Canadian National Collections as Homoeopteryx sumacensis, a saturniid moth.

(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.

light-trap

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

Crambid moth silhouette, Mindo, Ecuador

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.

Crambid moth, Mindo, Ecuador

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.

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

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.

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

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

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

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 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

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 bating orchid bees can attract a few dozens of males, as seen here. Photographed in Cayo District, Belize

A carefully selected site for bating 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

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.

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.