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Mozambique Diary: Pardalota

Pardalota reimeri, probably the most colorful and one of the rarest katydids in the world. The individuals I observed in Quirimbas are the first record of this species in 103 years.

Pardalota reimeri, probably the most colorful and one of the rarest katydids in the world. The individuals I observed in Quirimbas are the first record of this species in 103 years.

Ever since I can remember I have been having a recurring nightmare: I am in some incredible location – usually somewhere in the tropics, there are amazing insects everywhere, often those that I have been dying to find, but I need to leave immediately and have none of my collecting gear – not a single vial, no net, no camera (not everybody can relate, I realize, but entomologists know what I am talking about). And last month I finally got to live through this bad dream.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

A defensive display of Pardalota reimeri – these katydids feed on highly toxic plants and is likely that their bodies are loaded with poisonous alkaloids.

Before coming to Gorongosa I flew to the northern town of Pemba where a newly opened campus of the University of Lurió trains Mozambican students in biology and engineering. It was supposed to be a strictly-business trip, meeting lecturers and students, and for this reason I did not bring with me any collecting or sound recording equipment, and only the most basic photo gear. But my friend Harith had a better idea and decided to take me on a short trip to Quirimbas National Park, famous chiefly for its spectacular marine life. Some of his students were working on insect and amphibian faunas of the park, and I said, “Why the hell not.” The seemingly easy trip turned briefly into hell after our Mitsubishi truck decided to part ways with its clutch right in the middle of nowhere. After a long while a friendly driver in a passing car went to fetch a tow truck for us, and eventually we made it to the park.

An unidentified, aposemtically-colored tiger moth found on the same plants as Pardalota.

An unidentified, aposemtically-colored tiger moth found on the same plants as Pardalota.

The first thing that I noticed was the wall of insect sound. The lush miombo forest reverberated with loud katydid calls, ones that I did not recognize. They were unusual for a couple of reasons. One, it was the middle of a hot, African day, and katydids tend not to like it, preferring to call under the cover of the night. And two, the calls were continuous, low frequency, and very complex. They were telling everybody with ears, “Here I am, come and get me.” And when you do that you better have a good trick up your sleeve to protect yourself, as katydid ladies are not the only ones listening: birds, lizards, monkeys, they all love big, juicy insects.

The katydids were calling from high in the trees and I was afraid that I would not be able to catch, or even see them. But then one flew down from the canopy and landed right in front of me. When I saw what it was, my heart skipped a beat – it was Pardalota reimeri, the Holy Grail for katydid aficionados (there are a few of us out there). This species had been known only from the original type series, described in 1911 and preserved in a museum in Berlin. What is special about this species is that even those old, dried husks retained vivid, crazy colors, unlike those of any other known katydid species. And colors as awesome as this indicate an equally awesome biology.

I caught the katydid and he immediately went into a defensive mode: he opened his bright purple, black and white wings, and exposed his neon-orange abdomen and cervical membrane; he lifted his hind legs that had yellow and black markings, remarkably similar to those of toxic chrysomelid beetles. This was either a daring bluff, or this thing was seriously poisonous. All around me other males continued to sing.

A video of a P. reimeri nymph – although the insect is not feeding it gives the perfect illusion of the front end of a fuzzy caterpillar chewing on a leaf.

What to do? Here I was, surrounded by a remarkable entomological discovery, but with no way to collect, preserve, or record it. I decided to exploit Harith’s students and we fanned out looking for the insects. Soon we discovered where they sang – they were only calling from, and feeding on, two species of trees, both known to produce potent chemical defenses, including some powerful psychoactive alkaloids. This almost certainly explained their aposematic coloration. We also found nymphs of this species, which turned out to be incredibly hairy. In fact, when I first saw one I thought I was looking at a fuzzy caterpillar feeding on a toxic plant – its movements were an uncanny imitation of the front end of a caterpillar chewing on a leaf, even though I was looking at at the katydid’s butt. It wasn’t shocking then when a minute later I noticed very similar looking caterpillars feeding on the same plant and, also on the same plant, tiger moths (well known to be toxic) wearing colors very similar to those of the katydids’. Having nothing else at my disposal I pointed my Canon 6D at the canopy and used its video recording feature to record the sound of the singing males. I collected as many individuals as I could, stuffing them into Ziplock bags, hoping to be able to get decent photos and proper sound recordings later on.

In the end I managed to collect enough material and data to write a short note about the biology of this species. But not being able to do a very good job at data and specimen collecting in the field was not a pleasant experience. I have already learned never to go anywhere without my headlamp, a GPS, and a camera, and now I am adding to this list an ultrasonic sound recorder and a large set of vials with 96% ethanol. On the second thought, maybe also an extra clutch for a Mitsubishi and a satellite phone. And some beer, for emergencies.
Two nights later I had a nightmare about Quirimbas.

A female P. reimeri cleaning her foot.

A female P. reimeri cleaning her foot.

Who was Per Brinck?

Brinckiella elegans – a beautiful species from Western Cape Province of South Africa. Females of all species in this genus, and males in at least one, are completely wingless. This is rare among katydids and I still don’t have a good explanation for this loss of the ability to both fly and produce courtship calls.

Brinckiella elegans – a beautiful species from Western Cape Province of South Africa. Females of all species in this genus, and males in at least one, are completely wingless. This is rare among katydids and I still don’t have a good explanation for this loss of the ability to both fly and produce courtship calls.

Taxonomists, myself included, are often asked how we choose names for the organisms we discover and describe. Some are surprised to learn that species are often named after people, but that is also inappropriate to name species after yourself (albeit I know of one such case*). Naming species and genera after people is in fact so common that taxonomists rarely pause to ponder who Welwitsch (Welwitschia), Scudder (Scudderia), or Wahlberg (Clonia wahlbergi, Aquila wahlbergi, Arthroleptis wahlbergi and more) might be or have been. 

As I am sitting in front of my miscroscope, preparing a description of yet another African katydid of the genus Brinckiella, I realize that it never occurred to me to find out who Brinck was, the person after whom the genus was named in 1955. All I know is that he was one of the editors of a monumental, 15-tome treatment of the results of an expedition across southern Africa in 1950-1951. It was during this expedition that a single, tiny green katydid was collected, later to be named after its collector Brinckiella viridis by a French entomologist Lucien Chopard.

For some reason I assumed that Brinck, whoever he was, must be long dead – somebody who published a 15-tome treatise in the early 1950’s would have to be at least 120 by now, right? Well, yes and no. Professor Per Brinck has indeed died. But he only died two months ago, at the age of 94 in his home in Oland, Sweden. He was that country’s leading ecologist, one of the founders of the Nordic Foundation Oikos and editor of the journal Oikos. He was also a an expert on whirligig beetles (Gyrinidae) and dragonflies. He might have liked to receive a copy of my revision of the genus Brinckiella, which I published with my friend Corey Bazelet a few years ago. Alas, I never thought of it and now it’s too late.

An so, next time you run across an insect’s weird name that sounds like it might have been named after somebody, make an effort to find out who that person was. That – let’s pick a random patronym – Naskreckiella may bear the name of somebody very interesting, you just never know.

B. karooensis occurs in karoo vegetation along the western coast of South Africa.

B. karooensis can be found only on karoo vegetation along the western coast of South Africa.

 

*) Wall’s krait (Bungarus walli), a highly venomous snake related to cobras, was named by Frank Wall, a British officer and a medical doctor working in India in the early 1900s. His paper is a delight to read, here is an excerpt where he justifies naming the species after himself:

“[...]At the Club in the afternoon I was pursued by an urchin who produced another specimen which, to my satisfaction, I found to exactly accord with the morning one, and after getting home while dressing for dinner the same boy brought me a third, identical in the peculiarities first noted. Thus in one day I acquired three specimens of a snake hitherto unknown ! I may mention that the day’s bag exceeded 100 snakes of all kinds ! These three Kraits were all small. Since this I have obtained 8 of the same species, and though I believe it a breach of ethics for any naturalist to call a species after himself, the fact that this is the first new snake I have discovered in 11.5 years’ hard collecting, may be pleaded as sufficient excuse for commemorating the event and attaching my own name to it.”

Wall, F. 1907. A new krait from Oudh (Bungarus walli). J. Bombay Nat. Hist. Soc. 17:155-157.

The amazing Glass katydid

A young nymph of Glass katydid (Phlugis teres) from Suriname sitting on the tip of my finger.

A young nymph of Glass katydid (Phlugis teres) from Suriname sitting on the tip of my finger.

Once again things have been slow on my blog as I am trying to finish a million little things before my upcoming departure for Mozambique. I will be arriving there at the beginning of the rainy season, which means tons of insects and other invertebrates, a multitude of frogs, and hopefully some great new stories for this blog.

One of the animals that I hope to see there is a pretty, yet unnamed katydid from Mt. Gorongosa, which I first found last year in the mid-elevation rainforest on the mountain slopes. I am now working on its formal description and will post its photos as soon as the paper is out. In the meantime I thought I would present one of its close relatives, the amazing Glass katydid from Central and South America, a member of the genus Phlugis (Listroscelidinae).

As they age, Glass katydids begin to lose their transparency, and older nymphs and aduls acquire pale green coloration.

As they age, Glass katydids begin to lose their transparency, and older nymphs and aduls acquire pale green coloration.

I coined the name Glass katydid after seeing for the first time young nymphs of Phlugis teres, a species found in Suriname, who display remarkable, nearly complete transparency of their bodies. These minute insects truly look as if they were made of glass and, peering closely, it is possible to see most of their internal organs, including the entire tracheal system. Unfortunately, these katydids lose most of the transparency as they get older, and eventually acquire pale green coloration, occasionally marked with brown accents.

It would seem that something so seemingly fragile cannot feed on anything other than dew and rose petals, but in fact Glass katydids are agile, powerful predators. Unlike most of neotropical katydids, the genus Phlugis includes many diurnal species that use their excellent vision to find prey, and their hunting technique is very clever. Glass katydids are sit-and-wait predators who spend most of the day sitting upside down on the underside of large, thin leaves, usually at the edge of the rainforest or in open, shrubby habitats. They prefer leaves that are fully exposed to the sun so that any insect landing on its upper surface will cast a dark, sharply defined shadow. And that shadow is what Glass katydids are waiting for – it tells them whether the insect is a hard beetle (not good) or a soft fly (excellent), and if the insect looks like a good meal they launch themselves from under the leaf and onto its surface, and capture the victim with their long, very spiny legs in a blink of an eye.

In addition to being some of the most sophisticated and fastest orthopteran predators, Glass katydids are famous for the sound they produce – their call exceeds the frequency of 55 kHz, which is about three times the frequency a human ear is capable of hearing. A closely related genus Archnoscelis holds the record of producing the highest frequency call among all invertebrates – a whopping 129 kHz, twice the frequency of echolocation of most bats, and about 10 times more than the hearing ability of most adult humans. Another reminder that the ability to look cool and do amazing things seems to be inversely correlated with the body size.

Their huge eyes are a good indication of Glass katydids’ mode of hunting – they are diurnal sit-and-wait predators of small flies and other soft insects. This newly discovered, yet unnamed species from Costa Rica hunts small flying insects along the edges of mid-elevation rainforest.

Their huge eyes are a good indication of Glass katydids’ mode of hunting – they are diurnal sit-and-wait predators of small flies and other soft insects. This newly discovered, yet unnamed species of Phlugis from Costa Rica hunts small flying insects along the edges of mid-elevation rainforest.