Mimicry. Oh, the mimicry.

Mimicry is amazing, and a topic that I find incredibly satisfying to witness first-hand in the field. I’ve been lucky enough to see wasp-mimicking katydids before, as well as a couple of ant mimics, but these past few months I’ve seen several other examples that have left me awestruck (some which were on my bucket list!). Let’s see what we’ve found:

Acanthops tuberculata, a boxing mantis that mimics dead leaves

Acanthops tuberculata, a boxing mantis that mimics dead leaves

I was the sole student of one of my courses (Special Topics on Animal Behavior), so the classes were basically a conversation between me and my professor. While in the middle of reviewing the pros and cons of a particular study, my prof looks out the door and says “That leaf has legs! That’s a mantis!” Sure enough, we went over and saw it, a stunning Acanthops tuberculata (ID according to Lombardo & Ippolito, 2004).  These stunning mantids are dead leaf mimics, and it sure looked like one. When seen up close, it was like looking at a (very cool) alien.

Alien mugshot

Alien mugshot

These mantids even hang upside down and sway to and fro randomly, as if saying “I am a leaf on the wind”*, which I find incredibly interesting since it’s both physical and behavioral mimicry.

Now we move on to wasp mimicry, a very common occurrence in the insect world. This year I saw two great examples:

Ichneumon mimic (top) and Polistinae model (bottom)

Ichneumon mimic (top) and Polistinae model (bottom)

This is a pic from one of my sweep samples. The wasp at the top is an ichneumon wasp, a parasitoid of insect larvae; the wasp at the bottom is a polistine wasp, a very common predatory wasp. The resemblance is uncanny, and I’d love to be able to study this particular case of mimicry in greater detail.

But a wasp imitating another wasp seems relatively easy (they are close relatives, after all). But what about an insect in a different order? We saw it with the katydids, and this time I saw it with another, less common group: Mantisflies! Some of these amazing little neuropterans have been reported to be wasp mimics (Opler 1981), but I didn’t think they’d be this good.

This is a Synoeca wasp, with its metallic black color and blueish hues on its wings.

A Synoeca wasp

A Synoeca wasp

And this is Climaciella obtusa, a mimic of Synoeca wasps.

Identity crisis: Not a mantis, not a fly, not a wasp.

Identity crisis: Not a mantis, not a fly, not a wasp.

The level of detail in this example of mimicry is astonishing, and I only recognized it as something that was not a wasp because of the way it walked. A stunning find, and a very happy entomologist as a result.

I will be starting sampling at a new site soon, and I hope to find more examples of mimicry, both morphological and behavioral!

*You win 25 internet points if you understood this Firefly/Serenity reference. Shiny!

References:

Lombardo, F & Ippolito, S. 2004. Revision of the Species of Acanthops Serville 1831 (Mantodea, Mantidae, Acanthopinae) with Comments on Their Phylogeny. Annals of the Entomological Society of America, 97(6):1076-1102.

Opler, P.A. 1981. Polymorphic Mimicry of Polistine Wasps by a Neotropical Neuropteran. Biotropica, 13, 165−176. http://dx.doi.org/10.2307/2388121

I have no clue what happened here

Last weekend I went with on a field trip to Guáquira Ecological Station in Yaracuy, Venezuela. During a walk to one of our field sites we passed a group of plants in the family Musaceae, and a small protrusion caught my eye. On the side of the leaf stems I saw a katydid in the subfamily Conocephalinae, tribe Copiphorini staying very still. As I got closer, I could see that it was dead. What was interesting is that it died while, apparently, laying eggs:

Laying eggs?

Laying eggs?

But there was something that didn’t quite add up. Upon closer inspection, the insect was fixed to the side of the stem only by the ovipositor, and there were no eggs to be found.

Oviposicion-02

The legs were awkwardly folded underneath, it looked faded and it was in a conspicuous position; it had many signs of having been infected with a parasitic fungus, except there were no spores, fungus body or anything that looked like fungus. Very odd indeed. Then I looked at the other side, and things got stranger:

Parasitoid exit hole

Parasitoid exit hole

That looks like a parasitoid exit hole, which makes little sense, at least from what I’ve seen in the field. I usually see these exit holes in eggs, larvae or pupae, not adults, but it’s possible. There are tangle-veined flies (Nemestrinidae) that have been reared from katydids, as well as some tachinids like Homotrixa alleni, but nemestrinids and most tachinids are larger than this exit hole. So what could this be? A random occurrence? A parasitoid that modifies the host’s behavior and makes it die while making an attempt at laying eggs? A katydid that had a parasitoid inside it and then got infected with a fungus that modified its behavior, but the parasitoid ate the katydid from the inside out before the fungus could? I have no clue; all I know is that I’ll keep my eyes open in case I see something similar next time I go! If anyone has a clue about this, I’d love to know!

 

My bucket list got shorter

Venezuela is a beautiful country, with everything from deserts to rainforests, snowy mountains to seasonally flooded savannas. I’ve been fortunate to have traveled to many of the different environments along the northern coast, from the arid Paraguaná peninsula, where I saw the world’s largest grasshoppers, to the incredibly biodiverse Paria peninsula, where I swam at night in a bioluminescent beach and released sea turtle hatchlings. However, I hadn’t visited the central part of the country, the Llanos, a vast, flat savanna teeming with wildlife. This changed this past weekend when I was asked to accompany the Ecology I course to Hato Masaguaral, so I could show undergrad students insect collecting techniques and show them how field work was done and just how different it was from lab work (many of them were interested in cell/mol bio, and due to a series of unfortunate events this was their first ever field trip).

A few hours after leaving the temperate climate of the mountains around Caracas we arrived at Los Llanos biological Station, where we made a brief stop. A few minutes after walking around the station and seeing an american kestrel nesting inside a termite mound, the course’s TA called me over so I could take a pic. She was pointing up at a tree stump with a smile on her face, saying “Look, it’s so cool!”. I looked up and there it was, a common potoo!

Tree stumps with feathers are common

Tree stumps with feathers are common

After a short drive, we arrived at Hato Masaguaral, we got settled in the houses for researchers. They were teeming with tree frogs and other critters, like this gravid female mantis that was on our doorstep

Stagmatoptera sp.

Stagmatoptera sp.

After dinner we were getting ready to go to the field very early the next day, but as I was taking a shower I heard one of the students, out of breath, tell the teacher that there was a snake in the bathroom. I quickly dried off, got my camera and saw it, a little colubrid that feeds mainly on small frogs. It was in the bathroom’s water tank, so we carefully took it outside for a quick picture before it slithered off.

Leptodeira annulata

Leptodeira annulata

We were up quite early the next morning, setting up the mist nets to capture and measure birds. It was a great sight, seeing everyone chirping with excitement (although many were half asleep) under a starry sky. It was a perfect photo opportunity.

Field work starts early and covered by stars

Field work starts early and covered by stars

After setting up the mist nets, we walked for a few minutes while the sun rose. In the meantime, one of the TAs (an expert in tracking mammals) showed the students how to recognize paw prints in the mud.

A typical sunrise in los llanos

A typical sunrise in los llanos

Around 8 am we headed back to the mist nets to see if we had collected anything. Sure enough, there were two troupials (our national bird) and two lineated woodpeckers. Our troupials are colorful birds, and they have quite a temper!

Icterus icterus

Icterus icterus

After that, the actual field work began. Under the scorching sun we walked towards the field site where the students would collect soil samples. I was ecstatic; amazing birds left and right, meter long snakes, crocodiles and lizards. Despite it being extremely hot and dry, there was plenty of wildlife. A few minutes later, I heard hoarse hissing sounds, as if something was exhaling loudly, and I was overcome with excitement, for I had been waiting ten years for this. They were hoatzins, shaggy, prehistoric-looking birds that are basically punk dinosaurs. They have long feathers that project upwards and backwards, like crests (which gives them their generic name, Opisthocomus).

IMG_8379

Opisthocomus hoazin

IMG_8385

We continued our walk torwards the field site, which to the students seemed like ten Km due to the scorching heat (we’re talking 42-44 C, with barely any wind and no clouds). Savanna hawks flew above us, while smaller birds rushed for cover when they heard us approaching.

IMG_8262

Buteogallus meridionalis

After a grueling mid-day field work session (and a slight scare, due to a student almost passing out from the heat), we headed back to camp. As we scouted for a place to set up the camera trap, one of the students squealed with delight as she pointed towards the trees. It was a small group of capuchin monkeys (Cebus olivaceus)! The alpha male wasn’t too thrilled to see me close by with my camera, and he rattled the branches as he grunted and screamed at me.

This is not a happy face

This is not a happy face

When we finally got back to camp, we were treated to a tour of the crocodile nursery. There they breed the critically endangered Orinoco crocodiles and release them in specific areas once they reach a certain length.

Chillin' in the nursery

Crocodylus intermedius

The following day I had only one other item to cross off my bucket list: See a burrowing owl. So a fellow colleague and ornithologist asked me to go with her first to a nearby pond to check out the aquatic birds, and after that we would look for burrowing owls. We saw plenty of birds on our way:

IMG_8618

Aplomado falcon, Falco femoralis

I hadn’t seen a large group of aquatic birds before, and seeing all of them fly at once is something amazing. It’s a living cloud, basically. We quickly counted the two species of whistling ducks (Dendrocygna autumnalis and D. viduata) and the black-necked stilts (Himantopus mexicanus) before heading over to the dunes to look for the burrowing owls.

Los Llanos went a little overboard with the Clone tool

Los Llanos went a little overboard with the Clone tool

Then, to finish an amazing trip, I saw them. After almost two decades of only seeing them in calendars and books, I saw them in real life. These little owls have a perpetual stare, and they make their nests underground.

IMG_8652

Athene cunicularia

All in all, despite the excessive heat and extremely dry environment, it was a fantastic trip, and I can’t wait to go again. I crossed several items off my bucket list: hoatzins, burrowing owls, deer, crocs, several eagles/haws/kestrels/falcons, and the Llanos themselves. Next time I will collect insects so I can leave an insect box at the camp’s museum. More pics will come in the future!

Trying out the wide angle macro technique

It’s been a while since I’ve gone on a leisure insect photography walk. Today I had the opportunity to walk around a small ecological garden in the middle of the city, where one of the students showed me a large caterpillar, Pachylia syces (ID by Dr. Andrew Warren). I took this shot with my usual 100mm macro lens.

Pachylia syces caterpillar

However, having seen some fantastic wide angle macro work by Piotr Naskreki and other amazing photographers, I thought I’d give it a try. There’s still plenty of room to improve, but overall I’m quite pleased with my two first tries. They really do add a lot of context to the images!

A Pachylia syces caterpillar inching its way down from a Cecropia tree.

A Pachylia syces caterpillar inching its way down from a Cecropia tree.

A closer shot of the caterpillar

A closer shot of the caterpillar

I will definitely try this technique again soon! It works best with larger subjects, like beetles and frogs, but I really enjoy the added context.

Campus sweep (a.k.a. an early Xmas)

If any of you readers follow me on Twitter, you’ll know that I have a slight bias towards collecting arthropods by sweeping with an insect net. It lets you collect an incredible diversity of arthropods in a small area and with minimal effort. Sure, it helps that I live somewhere with an incredible biodiversity, but I still prefer sweep samples over all other collecting methods. (Next in the top three are light traps and active collecting). So after an afternoon of presenting theoretical projects on experimental design, we (my labmate and I) were ready to relax for a bit. We headed towards a little area of my U’s campus armed with nets and a small jar of alcohol, and after 10-15 min of walking around and getting asked what we were doing by people passing by, we ended up with a nice jar full of bugs.

Sure, it’s finals week, and we only have exams, projects, jobs and a plethora of other responsibilities, but I couldn’t help but sorting through the samples as soon as I got home. I was hoping to find what we dubbed “the mantis fly”, a fly with raptorial front legs belonging to the family Ephydridae (Ochthera sp.). My labmate found two in some sweep samples she did when we went to the field last year, and she then found another one in a sweep we did on campus, so naturally I had collector’s envy.

So I turned up the music, grab some coffee and start sorting; not two minutes after that I saw it: I had finally found one! Just look at those amazing forelegs!

A shore fly, Ochthera sp.

A shore fly, Ochthera sp.

I was pumped, so I kept sorting. I was surprised not only at the amount of crab spiders (family Thomisidae), but at their striking color patterns. Online I usually see white and yellow females, and I’ve found one or two males with green forelegs and stripes on the cephalothorax, but nothing like this! At first I thought that only the males were so boldly colored, but several female specimens proved me wrong.

Crab spider diversity with bold color patterns

Obviously, I was like a kid in a candy shop. Colorful specimens with weird shapes are a collector’s dream. Then I stumbled onto something that looked like a crab spider, but something was off; the abdomen was much slimmer, and when I looked at the eyes, the arrangement was nothing like the traditional thomisid pattern, which is 8 eyes (all more or less the same size) arranged in two almost parallel rows.

Lynx spider, family Oxyopidae

Lynx spider, family Oxyopidae

I think this is a lynx spider (family Oxyopidae) that has two greatly enlarged pairs of forelegs. This convergence isn’t unheard of in spiders; jumping spiders of the genus Lurio also have similar forelegs, but this is the first time I see it in lynx spiders.

I also found a few other interesting specimens, such as a parasitic wasp with a sculptured thorax, a myrmecomorph rove beetle, a spotted orb weaver and an iridescent tortoise beetle. All in all, this was a fantastic sweep, and I hope future visits hold even more surprises!

Araneidae

Tiny orb weaver with a striking color design

Small ant-like rove beetle (Staphilinidae)

Chrysomelidae

Tortoise beetle (Chrysomelidae: Cassidinae)

Eucharitidae

A parasitic wasp, Orasema sp. (Eucharitidae). These are parasites of ant larvae.

A light trap in the city

I have always been interested in biodiversity. The incredible array of shapes, sizes, colors, habitats and adaptations of organisms is something I find fascinating.

I have been fortunate enough to have done field work in many different locations, from beaches to the cloudy rainforest to the Andes, and as a result I have seen incredible forms of life, particularly insects: snake mimicking caterpillars, antlion larvae, tarantula hawks, lanternflies, wasp mimicking katydids, grasshoppers the size of my hand and an array of shapes, colors and behaviors that defy belief. Yet I’m aware that most people that live in cities will only see these organisms in TV documentaries; biodiversity in urban environments is usually much, much lower than in places with little or no human intervention. Part of my current work focuses on finding out just how diverse insects are in urban environments, how human intervention is affecting insect populations (or will affect them in the future) and what we can do to preserve or increase this diversity. That means that we have to photograph/collect insects, so last night we set up a light trap in an arboretum in the middle of the city. There were plenty of other light sources nearby, as well as streets, cars, houses, small shopping centers and the like, so I wasn’t expecting much; a previous attempt yielded only two microleps to the light trap. Still, I wanted to see what would come.

Not two minutes after setting up the trap, we had our first visitor, a crane fly. We had a few microleps, some bark lice, a few different beetles (Cerambycidae, Staphilinidae and other tiny ones), several wasps and a butterfly or two, among others. It was barren compared to any light trap I’ve set up in the field, but there was something interesting: it was surprisingly diverse! Out of all the insects that came to the trap, I only saw three species that had more than one specimen, and none had more than four. Almost all were very small (under a centimeter), save for three butterflies, one true bug and a wasp. Nevertheless, I considered it a success. More light traps will be set up in the coming months to see just how diverse the arboretum really is.

I’ll leave you with a few pics of some of the insects we saw! Any help with IDs will be greatly appreciated, particularly for the last one.

Compared to the other wasps, this ovipositor was tiny

That tiny “neck” makes me giggle (Braconidae: Microgastrinae)

Another parasitoid with a long ovipositor

Another parasitoid  with a long ovipositor

Bug with two parasitic mites

Each little black mark on this bug is a tiny spine

Lacewings are regular visitors at urban light traps

Lacewings are regular visitors at urban light traps

Palps on this moth look like little horns

Palps on this moth make it look like a furry, winged babirusa

This butterfly looked brown. Use a flash and iridescence does its thing.

This moth looked brown. Use a flash and iridescence does its thing.

An ichneumon wasp, the giant of the light trap (~3 cm)

An ichneumon wasp, the giant of the light trap (~3 cm)

Dorsal and lateral view of the same butterfly

Dorsal and lateral view of the same moth

This ovipositor is almost 3x the wasps body length

This ovipositor is almost 3x the wasp’s body length

Miniature wasp. 1.76 mm long. Yes, millimeters.

Miniature wasp. 1.76 mm long. Yes, millimeters.

Tiny bark louse (Psocidae)

Tiny bark louse (Myopsocidae)

Pterophorids are always fun to watch

Pterophorids are always fun to watch

No clue regarding ID. Ideas?

No clue regarding ID. EDIT: Derek Hennen (@derekhennen) and Wikispecies Editor (@stho002) ID’d it as a dustywing (Neuroptera: Coniopterygidae)

The thing in the pits

You leave your home in the morning, as you do every day. On your way to work, you walk past a deep, conical pit, dug in fine sand, with smooth edges that lead to a small cavity at the bottom. As you continue walking, you notice more of these pits; they vary in size, but they are all the same shape.

The pits

Soon, you get too close to the edge of one of the pits, and a flurry of rocks blast from the bottom of the pit and hit your legs; before you know it, you’re tumbling down the sides of the pit, and if you try to slow yourself down and scale the smooth surface back to the top, you’re hit with another wave of rocks thrown at you from the center of the pit. Finally, you reach the bottom, where you can only see them when it’s too late: Two massive jaws, each with several sharp, pointed teeth, grab your sides and a creature you can’t see starts eating you while you’re still alive.

While this may seem like the plot for a SyFy original movie, this is a common occurrence in the insect world. The unfortunate creature that met its demise at the bottom of the pit is an ant, and the undescribed monster with the massive jaws is an antlion larva.

The thing in the pits

Antlions belong to the family Myrmeleontidae in the order Neuroptera, and its closest relatives, the lacewings and owlflies (Chrysopidae and Ascalaphidae, respectively) also have predatory larvae. However, they are active hunters, unlike antlion larvae; these dig conical pits in fine sand and wait for ants or other small arthropods to walk close to the edge, and when one does, they fling grains of sand at them until they tumble down the pit and into their massive jaws.

Now, as you can see in the above pic, they are basically huge abdomens with massive scissor-jaws. So how can they possibly hide? Easy: they have fine hairs all over their body that trap dust and sand, and then they bury themselves deep until only part of the jaws are visible at the bottom of the pit. Once buried, they wait motionless for an unsuspecting prey to walk by.

Of course, they’re very easy to see once they’re on a white surface and (somewhat) clean:

But place them on soil, and they immediately cover themselves with it and are notoriously hard to spot unless they move:

I enjoy seeing these larvae because they are a) Visually awesome and b) They show spectacular behavior when they’re capturing prey. I definitely wouldn’t want to be a small arthropod near one of these pits, particularly when I know what’s at the bottom!