Archives

Mozambique Diary: The House of Spiders

A guest post by Edward O. Wilson

The skeletal remains of the Hippo House, once a busy restaurant and observation point.  Orb weaver (Nephilengys cruentata) from the Hippo House.

The skeletal remains of the Hippo House, once a busy restaurant and observation point.

Each spider in the Hippo House was sheltered in a tubular retreat, a behavior typical of all species in the genus Nephilengys.

Each spider in the Hippo House was sheltered in a silken, tubular retreat, a behavior typical of species in the genus Nephilengys.

At the end of a long rutted road in the park sits a conspicuous artifact in the midst of wilderness. Built in 1970, the Hippo House was the vantage point, the antigo miradouro, from which well-heeled tourists, cool drinks in hand, watched wildlife herds as they grazed over the vast floodplain grassland below. Today the herds are back, but the house is a seldom-visited ruin. During the Mozambique civil war, almost all the buildings of Gorongosa National Park were torn down or blown away, leaving behind a few remnants scarred by bullets. The house had been reduced to a shell of its original self.

When I first visited the Hippo House, Mozambique was in the middle of the winter dry season. Other than along the watercourses, the vegetation of Gorongosa was brown and withdrawn. Insect life was still abundant, but harder to locate. I had been told that spiders, big ones, were abundant at the house, but I was quite unprepared for what I found. The interior of the ruined building was powder dry. Its floor, stanchions, and ceiling were windblown and coated with dust. No vegetation reached in from the outside, and except for a few small geckos resting on the pillars, there was no immediate sign of life of any kind. Instead, torn webs and long single threads of silk dangled from the ceiling like ghostly decorations in a haunted house. They swung gently back and forth in the occasional light breeze. No other movement or sound came from the seemingly empty space.

An unlucky katydid that flew into a web under the Hippo House is immediately killed and wrapped in silk by a female orb weaver.

An unlucky katydid that flew into a web under the Hippo House is immediately killed and wrapped in silk by a female orb weaver.

Where were the spiders I expected? Not one could be seen. But I knew they must be there someplace, alive, perhaps watching us. The idea of a hidden arachnid horde ready to rush out made me uneasy. Soon I saw something else: round objects plastered onto the ceiling. They were dusty and silent. My companions and I picked up a stick lying on the ground outside that was long enough to reach the ceiling, and tore two of the pouches apart. They proved to be silken egg pouches, undoubtedly made by spiders but now dry and empty; we were obviously not in the breeding season. The spiders themselves stayed hidden. Where were they? I grew more apprehensive.

We saw other, much larger, oblong pouches scattered over the rough eroded ceiling. At the tip of each was a circular entrance opening to a hollow interior. Using a flashlight and looking straight down the chamber, we could see what lay within. There at the rear of each pouch crouched a large spider, facing outward, its fangs, eyes, and the front of its tightly bunched legs visible. I wanted to see a specimen well enough to identify it, but hesitated. I was, to be frank, afraid of these crouched and waiting spiders. I suffer from mild arachnophobia. This spooky place was the setting of an arachnophobe’s nightmare.

The golden orb-weaver (Nephila senegalensis) is one of the largest spiders of Gorongosa. Its name comes from the beautifully golden coloration of its silk.

The golden orb-weaver (Nephila senegalensis) is one of the largest spiders of Gorongosa. Its name comes from the beautifully golden coloration of its silk.

We selected one of the pouches and poked at it in and out, but the spider stayed tight inside. One of my companions then took charge. He tore open the pouch and shook the inhabitant out into a transparent plastic bag. At last I could see what had lain within. The spider was heavy-bodied, the size of a thimble. When it suddenly spread its spiny legs, its width almost tripled.

I had solved the mystery of the spider house, at least in theory. The creatures in the silken bags were orb weavers, members of the spider family Nephilidae, called golden orb weavers, and, I later learned from an arachnologist, the species is Nephilengys cruentata. Some species of nephilids and the closely related araneids hide in retreats next to their webs; others remain in the centers of the webs. But how could there be so many spiders of this one species crowded together? Why are there no other creatures of any kind? The explanation I believed to be immediately clear. The floor of the lower level of the spider house is a layer of concrete. The interior is abnormally dry. Because the lower level cannot be invaded by any vegetation, few if any other forms of insect or arachnid life can live there. Yet flying insects undoubtedly fly through the wide-open space of the lower level, in through one side and out the other. A few might settle there to rest. The fate of most or all is the same: spider food.

Orb weaver (Nephilengys cruentata) from the Hippo House.

Orb weaver (Nephilengys cruentata) from the Hippo House.

My imagination was roused by this bizarre little world, but more so by my own reaction to it. When I took the captured spider back to Chitengo Camp, I found I was unable to make a specimen of it. That would mean fishing the monster out of the cellophane bag and working it into a bottle of preservative. So I simply opened the rear window of my room and dumped my captive live onto the ground below, where it would at least have a chance of making its way to a tree or building and spinning a new silken retreat.

I remember vividly the incident that made me an arachnophobe. I was eight years old. It was late summer, and I was exploring a vacant lot near our house. There were several full-grown female orb-weaving spiders in the high weeds, likely the common garden spider (Araneus diadematus), sitting in the center of their webs. I could not resist getting close enough to see all the details of one spider’s body. When I was about a foot away, it began to jerk back and forth in a menacing manner. I thought it was preparing to jump out and onto me. I ran. If that were not bad enough, I soon afterward saw a movie, the name of which I have long forgotten, in which a man is trapped in a cave. Blundering around, he becomes tangled in spiderwebs that are hung all around. Spiders, really big ones, climb down toward him, and . . .

Aversions and phobias of this kind, with the latter an extreme response causing panic and cold sweats, can be imprinted with as little as a single brief episode. They are rarely caused by a frightening experience with a knife, a gun, an automobile, or any other modern contrivance that can injure or kill. On the other hand, they easily and quickly follow a frightening experience with one of mankind’s ancient perils: snakes, spiders, wolves, heights, running water, and closed spaces. During millions of years of human prehistory, it has paid in a major Darwinian way to have quick, decisive response to the things that can kill you.

So I have forgiven myself for the wavelet of fear and revulsion I felt about the harmless denizens of the spider house. Let me make further amends by stressing that people are mostly safe amid what remains of living nature. We conquered the man-eaters long ago by destroying almost all of the big predators willing and able to hunt humans. They survive in our stories and in our legends of monsters. We imagine them silently emerging from caves and swamps, easing up from unexplored depths of the sea, or drifting down unseen from above. Walk into or swim in any wild habitat remaining on Earth, maintain the same level of caution you would on a city street, and you will be far safer than in most urban environments. Use common sense: don’t swim with crocodiles; don’t paddleboard among seals where great white sharks have been seen; and above all, never, ever run up to a mother grizzly bear with cubs to take a better look. Your greatest risk in the wild is from insect-borne disease—malaria, dengue, leishmaniasis, yellow fever—and these can be deadly if untreated. But they are transmitted chiefly among people. They can be easily avoided, and in any case pose less risk to you than the mélange of pathogens passing directly from person to person in human settlements.

The scary but harmless spiders in the Hippo House, and all the other animal species of wild environments like those of Gorongosa, are instinct-guided. They rigidly follow life-and-death routines formed during millions of years of evolution. Their lives are finely tuned and fragile in ways that are blessedly unthreatening to human beings.

Text Copyright © 2014 by Edward O. Wilson, Photographs Copyright © 2014 Piotr Naskrecki

Read more about the biological complexity and restoration of the fascinating ecosystem of Gorongosa National Park in “A Window on Eternity”, a new book by E.O. Wilson, with photos by P. Naskrecki (Simon & Schuster 2014).

Tarantulas, known in southern Africa as baboon spiders, may look frightening but are generally harmless. Their main line of defense is not their venom, but tiny urticating hairs that cover the entire body.

Tarantulas, known in southern Africa as baboon spiders, may look frightening but are generally harmless. Their main line of defense is not their venom, but tiny urticating hairs that cover the entire body.

Piotr Naskrecki and Edward O. Wilson in Gorongosa National Park, Mozambique.

Piotr Naskrecki and Edward O. Wilson in Gorongosa National Park, Mozambique.

 

Footprint Cave, Belize

Africa in Mesoamerica – a beautiful, little pool on the floor of the upper chamber of the Footprint Cave; it even has an adjoining pool that looks like the Arabian Peninsula.

Africa in Mesoamerica – a beautiful, little pool on the floor of the upper chamber of the Footprint Cave; it even has an adjoining pool that looks like the Arabian Peninsula.

It has been a long while since the last update to this blog, mostly because of my hectic travel schedule (in fact, I am typing this on a shaky train ride). But it has been an interesting time, with lots of great photo ops. Last week I joined Alex Wild, John Abbott and Thomas Shahan in Belize to teach BugShot 2013, an intense course in tropical insect macrophotography. Aside from working with a friendly group of photography masters and enthusiastic students it was my first exposure to some of the most interesting members of the troglobitic Mesoamerican fauna as the workshop was held at the Caves Branch Lodge in central Belize, an area famous for its karst formations, replete with deep limestone caves.

The most famous cave in the area is the Footprint Cave, named after calcified Mayan footprints found in the deeper section of the cave, along with a number of artifacts and skeletal remains. The cave was looted in 1994, and many artifacts and remains are now gone, but you can still see there ancient fire places and shards of Mayan pottery. It was quite an unreal and humbling experience to sit next to a pile of ash that might be over 2,000 years old but still looks warm. The cave itself is stunningly beautiful, cathedral-like, with massive stalactites that shimmer in the light of the headlamp. The shallow Caves Branch River flows through it, and as you walk along its bed large catfish and shrimp follow your every step, looking for small aquatic invertebrates flushed from under the sand.

Female cave cricket Mayagryllus apterus, a species endemic to the Caves Branch system of Belize.

Female cave cricket Mayagryllus apterus, a species endemic to the Caves Branch system of Belize.

As we walked deeper into the cave, leaving behind its large opening and eventually all traces of natural light, we began to discover a multitude of life forms that call this cave their home. Biologists explored Footprint Cave in early 1970’s, but little work has been done since. Many animal species found in the Caves Branch system are likely endemic, and some still await their formal scientific description. I was thrilled to see dozens of long-legged cave crickets Mayagryllus apterus, described only in 1993 from specimens collected in these caves. They were often accompanied by large, equally spindly amblypygids Paraphrynus raptator (Phrynidae), and apparently another, yet undescribed species of the family Charontidae is also present in the cave (and Gil Wizen might have found a third, possibly new amblypygid species). I was hoping to find some dinospiders (Ricinulei) there, alas, no such luck, but flipping rocks on the banks of Caves Branch River revealed a tiny, equally interesting arachnid, a pygmy vinegaroon (Schizomida). The species found in the Footprint Caves is a yet undescribed species of Schizomus, and I would love to be able to collect some specimens and describe them (I need to look into getting some permits for Belize).

A troglobitic isopod crustacean Troglophiloscia sp.; note its lack of pigmentation and eyes, characteristics typical of cave-dwelling organisms.

A troglobitic isopod crustacean Troglophiloscia sp.; note its lack of pigmentation and eyes, characteristics typical of cave-dwelling organisms.

Silk strands on the cave ceiling, produced by the larvae of predaceous fungus gnats (Keroplatidae: ?Macrocera sp.)

Silk strands on the cave ceiling, produced by the larvae of predaceous fungus gnats (Keroplatidae: ?Macrocera sp.)

Yet the most interesting organism in the cave was a fly. When we shone the light at the low celling of the cave we could see curtains of thin, glistening strands of sticky silk produced by larvae of predaceous fungus gnats of the family Keroplatidae; I have not been able to identify the species that lives in the Footprint Cave, but it is possibly a member of the genus Macrocera (Macrocerinae). The strands spun by the larvae are covered with droplets of oxalic acid, which trap and kill tiny flying insects, mayflies mostly, found in the cave. Members of a related subfamily Arachnocampinae found in Australia and New Zealand are famous for their bioluminescence, but the ones found in Belize are of the non-glowing variety. Still, it was a beautiful spectacle to see thousands of hair-like strands undulate gently in the breeze caused by a person walking several meters away.

The strands are covered with droplets of oxalic acid, which trap and kill unlucky insects, such as this mayfly, that brush against them in flight.

The strands are covered with droplets of oxalic acid, which trap and kill unlucky insects, such as this mayfly, that brush against them in flight.

Everybody was sad to leave the cave, which turned out to be the highlight of our photographic workshop, although the fauna of the rainforest that surrounded the lodge where we stayed was equally interesting. Not being able to collect anything was torture for me, but I hope that some day soon I will be able to come back to Caves Branch, this time wearing only my entomologist’s hat.

A new, yet unnamed species of the pygmy vinegaroon (Schizomus sp.) from the Footprint Cave.

A new, yet unnamed species of the pygmy vinegaroon (Schizomus sp.) from the Footprint Cave.

New life

The Transkei shieldback (Transkeidectes multidentis, 1992) was one of the first species that I described, based on a single specimen collected in 1947 near Port St. John's in the Eastern Cape of South Africa. Describing a new species based on a single specimen is a horrible idea (you never know whether you might be dealing with an aberrant form of something already known), and ever since I have been looking for more individuals to confirm the existence of this species.

The Transkei shieldback (Transkeidectes multidentis, 1992) was one of the first species that I described, based on a single specimen collected in 1947 near Port St. John’s in the Eastern Cape of South Africa. Describing a new species based on a single specimen is a horrible idea (you never know whether you might be dealing with an aberrant form of something already known), and ever since I have been looking for more individuals to confirm the existence of this species.

To my enormous relief, I have recently located a thriving population of the Transkei shieldback in the coastal forest of the Silaka Nature Reserve near Port St. John's. The species is real.

To my enormous relief, I have recently located a thriving population of the Transkei shieldback in the coastal forest of the Silaka Nature Reserve near Port St. John’s. The species is real.

Today marks the first anniversary of The Smaller Majority blog which, to my delight and surprise, has been steadily gaining readership. I am grateful to all who visited these pages over the last 12 months, especially those who kindly left the wonderful, insightful, occasionally snarky comments under many of the 130+ individual stories – keep’em coming! So far this blog has amounted to 75,000 words and 770 photos – that’s a decent size book; maybe I should have done that instead? Nah! And what better way to acknowledge the portent of this occasion than to talk about what I consider the most exciting aspect of my work as an entomologist – the discovery of new forms of life.

When I was about seven years old my father said something that, in retrospect, was probably the most important piece of information I have ever received, one that has influenced my entire life. I should mention that my father was an astronomer, and he did his best to try to entice me with his line of work, to no avail. (At some point he even built a telescope for me, but I only used it to watch birds and spy on my neighbors; I was a lost cause.) To my question about a possibility of finding life elsewhere in the Universe he replied that those chances were slim, but that our own planet still had many organisms that remained undiscovered and unnamed. That statement stopped me in my tracks. I instantly envisioned mysterious, dinosaur-like creatures hiding in the depths of African jungles. But he explained that the yet-unnamed animals were probably small, and that they might even be living in our own backyard. I am certain that at that very moment I decided to become an explorer who would spend his life questing for those elusive, undiscovered creatures. Of course, I did not realize then that most discoveries of new species take place among dusty drawers of museums, made by taxonomists whose lives are decidedly less than glamorous. But the stage for a career in entomology was set.

The Martian landscapes of the Northern Cape of South Africa, despite its foreboding appearance and extremely harsh conditions, is home to a number of very interesting orthopteroid insects.

The Martian landscapes of the Northern Cape of South Africa, despite their foreboding appearance and extremely harsh conditions, are home to a number of very interesting orthopteroid insects.

My friend Corey Bazelet and I discovered the handsome, wingless katydid Brinckiella arboricola Naskrecki & Bazelet, 2009 in the Geogap Nature Reserve of Northern Cape.

My friend Corey Bazelet and I discovered the handsome, wingless katydid Brinckiella arboricola Naskrecki & Bazelet, 2009 in the Geogap Nature Reserve of Northern Cape.

It took me fifteen years to run into a beautiful little gem of a katydid in a meadow in Turkey, an animal that until then had eluded entomologists. I named it Poecilimon marmaraensis, after the Marmara Sea on the shores of which this species occurs. The elation of knowing that I was the first person on Earth to find it was intoxicating. I am sure that all my fellow taxonomists have felt it at some point in their lives, and for many it is the ultimate reward. Finding new forms of life is to me one of the greatest adventures in biology, one that the current biodiversity crisis makes a pressing necessity. Extinctions and the appearance of new species are natural phenomena that once were fairly well balanced, with speciation always slightly outpacing extinction and making Earth’s biodiversity increasingly richer. But with the advent of man, this balance started to tip dramatically toward extinction, and we now lose species at a rate a thousand times higher than the natural, “background” one. Regardless of being named or not, each species gone extinct is another book of genetic code burned, another piece of the intricate puzzle of life on Earth irreversibly lost. And while destruction of natural habitats and the alarming pace of species loss give little hope for preserving all the components of Earth’s biota for future generations, we should make every effort to document all organisms that still inhabit our planet. Still, on some days, the nagging pessimist in me points out that maybe all that we taxonomists do is carve names on tombstones and write obituaries for species who may be gone by the time their formal, scientific names are published. He may be right, but I hope he isn’t.

In spite of all the evidence that the world at large simply does not care about most of our non-human brethren, I still believe that armed with the complete knowledge of all Life on Earth we will be able to make the best decisions as to where conservation efforts should be focused, and that we will manage to save a very high proportion of the world’s phyletic diversity and biocomplexity. The more diverse Life is, the more stable and capable of self-regulation are its assemblages. The more species alive, the more likely we are to discover new medicines, new crops, or new structures worth imitating. The more Life we have around, the more our own is worth living.

Brown-faced spear bearer (Copiphora hastata Naskrecki, 2000) – This huge conehead katydid is common across Central America. Females of this and related species carry an enormous ovipositor that allows them to lay eggs at the base of litter-filled fronds of small palm trees.

Brown-faced spear bearer (Copiphora hastata Naskrecki, 2000) – This huge conehead katydid is common across Central America. Females of this and related species carry an enormous ovipositor that allows them to lay eggs at the base of litter-filled fronds of small palm trees.

The Costa Rican rainforest is home to about 350 species of katydids, many yet unknown, of which I have so far discovered and named a little over 50.

The Costa Rican rainforest is home to about 350 species of katydids, many yet unknown, of which I have so far discovered and named a little over 50.

The Simandou Mts. blattodean (Simanoda conserfariam Roth & Naskrecki, 2003) is an insect that may be already extinct in the wild. I first found it in a cave in SE Guinea (West Africa), a place that was part of a large mining concession. Although mining operations in the Simandou were recently halted (presumably soon to be resumed), the cave was on the path of a major road that was being constructed and it may no longer exist.

The Simandou Mts. blattodean (Simanoda conserfariam Roth & Naskrecki, 2003) is an insect that may be already extinct in the wild. I first found it in a cave in SE Guinea (West Africa), a place that was part of a large mining concession. Although mining operations in the Simandou were recently halted (presumably soon to be resumed), the cave was on the path of a major road that was being constructed and it may no longer exist.

I described the Agile grasshopper (Rhachitopis brachyopterus Naskrecki, 1992) based on a small series of preserved specimens collected in Zimbabwe, but until recently have not seen a live individual. This is very common in entomology as most species are described using specimens from museum collections, often collected tens or even over a hundred years earlier.

I described the Agile grasshopper (Rhachitopis brachypterus Naskrecki, 1992) based on a small series of preserved specimens collected in Zimbabwe, but until recently have not seen a live individual. Such a situation is very common in entomology as most species are described using specimens from museum collections, often preserved tens or even over a hundred years earlier.

During the Cheringoma Plateou biodiversity survey in Gorongosa National Park, Mozambique, I crawled out of my tent one morning and the first insect I saw was my Agile grasshopper. Little compares to the joy of seeing for the first time a living individual of a species that you have described and named.

During the Cheringoma Plateau biodiversity survey in Gorongosa National Park, Mozambique, I crawled out of my tent one morning and the first insect I saw was my Agile grasshopper. Little compares to the joy of seeing for the first time a living individual of a species that you have described and named.

In addition to my work on insects, I have occasionally dabbled in arachnids. The Atewa dinospider (Ricinoides atewa Naskrecki, 2008) was an exciting discovery I made in SE Ghana.

In addition to my work on insects, I have occasionally dabbled in arachnids. The Atewa dinospider (Ricinoides atewa Naskrecki, 2008) was an exciting discovery I made in SE Ghana.

When it comes to yet undiscovered and unnamed species, Papua New Guinea is one of the richest places on the planet – nearly 80% of all species that I had collected there turned out to be new to science. One of the new species was the Ingrisch's katydid (Ingrischia macrocephala Naskrecki & Rentz, 2010), which my co-author David Rentz aptly christened "a katydid designed by a committee."

When it comes to yet undiscovered and unnamed species, Papua New Guinea is one of the richest places on the planet – nearly 80% of all species that I had collected there turned out to be new to science. One of them was the Ingrisch’s katydid (Ingrischia macrocephala Naskrecki & Rentz, 2010), which my co-author David Rentz aptly christened “a katydid designed by committee.”

Sweat the small stuff

Ground beetle (Anthia fornasinii) carrying a dead cicada. In South Africa these beetles are known under the charming name "oogpister" ("eye pisser") on the account of their ability to squirt defensive chemicals from their abdomen straight into the eyes of potential predators.

Ground beetle (Anthia fornasinii) carrying a dead cicada. In South Africa these beetles are known under the charming name “oogpister” (“eye pisser”) on the account of their ability to squirt defensive chemicals from their abdomen straight into the eyes of potential predators.

Recently I have been processing some of the 18,000+ photos I took during a recent trip to Mozambique, and yesterday one image caught my eye. It shows a large ground beetle carrying a dead cicada. I shot it rather casually one night in front of my tent in Gorongosa, and immediately forgot about it. But now, looking at it closely, I realized that I was guilty of the very same thing that I often preach against – I did not pay enough attention to the small things, and missed an interesting detail. Zooming in on the photo I noticed several ants milling around the beetle’s feet. More interestingly, one of the tarsi had a dead driver ant (Dorylus) permanently attached to it – the beetle had survived an attack by these notoriously vicious insects, which was quite impressive. But what were the other ants doing? I guess I will never know. I have made the same mistake in the past, where I would notice something interesting about the scene that I had shot, but only when it was much too late to go back and photograph it again.

A female Harlequin beetle (Acrocinus longimanus) from Guyana. The body of these insects is a vibrant ecosystem for several species of arachnids.

A female Harlequin beetle (Acrocinus longimanus) from Guyana. The body of this insect is a vibrant ecosystem for several species of arachnids.

But there is one thing that greatly helps in preventing this from happening – as Louis Pasteur succinctly put it, “In the field of observation, chance favors the prepared mind.” In the field of nature photography, the more you know about your subject, the more likely you are to notice something interesting or unusual, and refocus on that. My best example comes from Guyana, where a few years ago I found a gorgeous Harlequin beetle (Acrocinus longimanus). After taking a few photos of the animal I was about ready to let it go when suddenly some microscopically tiny  object ran across its body. I felt a spark in my brain reignite some old, long unused synapses, and recollections started flooding in – “That looked like a small scorpion. No, a pseudoscorpion. They are phoretic. One species is found only on Harlequin beetles. Cordylochernes scorpioides, that’s it!”

Large fig trees in South American rainforests serve as hosts to the spectacular Harlequin beetle, which completes its larval development in the wood of these plants. The body of this giant insect is in itself a vibrant ecosystem for several species of smaller animals. Hundreds of mites hide under the wings and in crevices of the beetle’s body, using the insect as a convenient way to move from place to place. The mites also serve as food for another passenger, the pseudoscorpion. But the mites are not the main reason why pseudoscorpions embark on the beetle’s back.

A phoretic pseudoscorpion (Cordylochernes scorpioides) uses the body of the Harlequin beetle to move from one fig tree to another, and to find mating partners and food.

A phoretic pseudoscorpion (Cordylochernes scorpioides) uses the body of the Harlequin beetle to move from one fig tree to another, and to find mating partners and food.

These arachnids spend their lives on the same fig trees that the beetles need to develop and where they seek mating partners, and thus the pseudoscorpions can be assured that by hitching a ride on a harlequin beetle they will end up on another tree of the same species. This also means that the beetle’s back is a great place to meet new partners who hopped on it to look for new fig trees to colonize, and a lot of sexual activity takes place among pseudoscorpions under the covers of the beetle’s wings. Some male pseudoscorpions never leave the beetle because they know that with each landing on a fig tree new females will embark, giving them more chances to pass on their genes. And because some time ago I had read a study that described all this, I did not miss the opportunity to photograph this fascinating symbiosis. Now, if only somebody wrote something about beetles and ants…

Unidentified phoretic mites on the body of a Harlequin beetle serve as food to pseudoscorpions.

Phoretic mites on the body of a Harlequin beetle serve as food to pseudoscorpions.

I missed this one – an African assassin bug from Guinea also has phoretic mites and pseudoscorpions, but I only noticed them while processing this photo. It is possible that their natural history parallels that of the Neotropical Harlequin beetle and its passengers.

I missed this one – an African assassin bug from Guinea also has phoretic mites and pseudoscorpions, but I only noticed them while processing this photo. It is possible that their natural history parallels that of the Neotropical Harlequin beetle and its passengers.

Mozambique Diary: Is this tortoise broken?

An adult Hingeback tortoise (Kinixys belliana) from Gorongosa. What looks like a wound on its carapace is a flap of skin that allows the shell to close and protect the hind legs and tail.

An adult Hingeback tortoise (Kinixys belliana) from Gorongosa. What looks like a wound on its carapace is a flap of skin that allows the shell to close and protect the hind legs and tail.

Some time ago I was driving in Gorongosa when I noticed a large tortoise laying in the middle of the road, stuck upside down in the mud. The animal was alive but had what appeared to be a large wound in the posterior part of its cracked carapace. There were fresh tracks of a civet all around it in the mud, and I assumed that the civet found an injured tortoise (I didn’t think a civet could do it itself) and was hoping to eat it. I pulled the animal out of the muck and only then recognized what I was looking at – the tortoise was not injured at all, and what I took for a wound was a flap of skin that connected the front part of the shell with its movable back. Because it was not an ordinary tortoise, but a Hingeback tortoise (Kinixys), a member of a remarkable group of reptiles that are capable of closing shut the back of their shells to protect the hind legs and the tail. This, combined with the head tightly pulled into the front of the shell and blocked by its heavily armed front legs makes the hingeback tortoise virtually immune from attacks by smaller predators. Judging by the dense trail of civet tracks around the tortoise it seemed that the mammal had spent a lot of time in frustration, unsuccessfully trying to get to the soft parts of the reptile.

A juvenile Hingeback tortoise; its hinge is not yet developed.

A juvenile Hingeback tortoise; its hinge is not yet developed.

Although the movable carapace is a great way to protect the rear part of the body, the flap of skin that connects the two components of the carapace is a favorite location for another enemy of the tortoises to attack – the ticks. Every tortoise I found in Gorongosa carried several huge, heavily armed ticks (mostly of the genus Amblyomma), whose body shape and sculpturing was surprisingly similar to that of the tortoise. Carrying a bunch of blood-sucking ectoparasites is no fun, but the burden of being drained by them is probably particularly heavy on smaller, younger animals. A few days ago I found a tiny Hingeback tortoise, one whose hinge was not yet fully developed, and it carried on its leg one of the largest ticks I have ever seen. It was as if I had a parasite the size of a football permanently attached to my body. I removed the tick from the tortoise, put one of the animals into a vial of alcohol, and applied some antiseptic to the other and let him back on his merry way.

An enormous tick (Amblyomma sp.) on the tortoise's leg.

An enormous tick (Amblyomma sp.) on the tortoise’s leg.

Hingeback tortoises are quite common in Gorongosa, and I see them often as they cross the network of trails. But across Africa their numbers are declining as the result of habitat loss and collecting for the pet trade. Every year about 20,000 of these animals are exported to be sold in pet stores in the US and Europe, and Mozambique alone sends out about 3,000 of these animals every year (this is the official quota allowed by CITES, the actual number is undoubtedly higher). Luckily, recently the importation of most of Hingeback species was banned in the US. The reason – ticks. Some of the ticks carry a disease which, while not harmful to the reptiles, is often fatal to cattle – the Heartwater disease, caused by rickettsia Ehrlichia ruminantium. And so, the same parasite that makes the tortoises’ life miserable may in the end help them survive in the wild. I guess you never know who your true ally is.

Tortoise tick (Amblyomma sp.) actually looks like a tortoise, and its opisthosma is almost as hard as the reptile's shell.

Tortoise tick (Amblyomma sp.) actually looks like a tortoise, and its opisthosma is almost as hard as the reptile’s shell.

Mozambique Diary: The stuff of dreams

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Banded-legged golden orb weaver (Nephila senegalensis) from Gorongosa [Canon 7D, Canon 14mm, Canon MT 24EX twin light]

Isn’t it fascinating that the same thing can be the subject of one person’s worst nightmares, and another person’s wildest dreams and desires? Nothing illustrates this point better than the Golden orb spiders (Nephila), which my wife doesn’t even call spiders – they are simply her Nemesis, clearly intent on luring her into their enormous webs and tangling themselves into her hair.

But today I had the pleasure of going into the field with two great arachnologists, Matjaž Kuntner and Ingi Agnarsson, who came to Mozambique with one dream and one dream only – to see and catch the largest orb weaving spider in the world, Nephila komaci. This species was discovered by Matjaž a few years ago among old museum specimens, but nobody has seen a live individual since. But there is an interesting twist to this story – the reason Matjaž and Ingi chose Gorongosa to look for this Holy Grail of arachnology was a small photo, a thumbnail really, of N. komaci that had appeared on the old Gorongosa’s website five years ago, two years before the species was officially described. We didn’t know where exactly the photo had been taken, but it had to be somewhere in the park.

We set out early in the morning to look for the elusive weaver, hoping that we might find it in the patches of sand forest in the southern part of the park. Alas, after several ours of trampling through the bush we came back empty handed, not in small part because of some confusion as to where the forest was, which made us end up miles away from our intended destination. But playing bait for lions for several hours this morning was not a complete loss, either. The spider men found a few interesting species, including a related species, the Banded-legged golden orb weaver (Nephila senegalensis). These are gorgeous beasts, huge and beautifully colored. Their orbs are often made of brightly yellow silk, hence the common name. A few years ago Simon Peers and Nicholas Godley used the silk of a related species from Madagascar to weave an extraordinary golden cape.

Tomorrow Matjaž and Ingi will continue their search, this time with a GPS and an even stronger desire to lay their hands on the dreamy arachnid.

A view from the other side

 A guest post by Kristin

The very first solifugid that I ever saw. When I posted this photo on Flickr, the always hilarious Brandi Schuster commented, “Solifugid. That sounds like the noise that I would make if I ever saw one of those fuckers in real life.” [Canon G10]

The very first solifugid that I ever saw. When I posted this photo on Flickr, the always hilarious Brandi Schuster commented, “Solifugid. That sounds like the noise that I would make if I ever saw one of those fuckers in real life.” [Canon G10]


“So, are you afraid of solifugids, too?” my husband asked, questioning me about my life long fear of spiders while writing his first book, The Smaller Majority. Now, I am not your stereotypical girl, revolted by and fearful of insects of all types. I love insects and pride myself on knowing more about them than most laymen. Consequently, I really didn’t want to admit that I didn’t know what a solifugid was, nor did I want to add any other arthropods to my shameful “eek!” list. Picturing something like an amblypigid, I replied, “Pfft, sheesh, phuff, no, of course not. Just spiders.” Little did I know.

The first time that I ever saw a solifugid was in South Africa in 2009. Long after nightfall, our group had finally made it to our accommodations – a research station in the hills of Cederberg. The mattresses were stained and soaked with things unholy, and bats were roosting and pooping in the rafters of the kitchen, but the real problem was the spiders. Big, hairy, and speedy.

Spider-free living. Hey, if I believed it, that was all that mattered. [Canon G10]

Spider-free living. Hey, if I believed it, that was all that mattered. [Canon G10]

It began to dawn on me that I couldn’t stay in that room, but we were hours away from any alternative. As I began to wrap my head around this puzzle, I heard commotion outside one of the rooms. Piotr was gasping things like, “Oh boy!” and scrambling for his camera gear in a way that suggested that he’d found something really “cool”, and our friend Maciej was pounding on the door, yelling in his thick Polish accent, “Corey! There’s a solifugid coming into your room!” The doors didn’t meet the floor, you see. Of course they didn’t. There was enough of a gap that the mouse-sized, spider-like thing that we stood staring at was able to skitter under Corey’s door without even ducking its head or pausing at chewing on a grasshopper.

The Verandah. Doesn’t it look delightful? Note the interesting choice to install a screen on a door that doesn’t meet the floor, and the lack of a screen on the window. [Canon G10]

The Verandah. Doesn’t it look delightful? Note the interesting choice to install a screen on a door that doesn’t meet the floor, and the lack of a screen on the window. [Canon G10]

So, I finally learned: solifugids look like a cross between a bleached mouse and a spider, and they live in dry regions in South Africa. Also, charmingly, they are carnivores. I slept in the car that night and the following morning we paid the spiders for our room and board. It wasn’t until 2 years later that my solifugid lessons resumed, at graduate level.

Again, I was in South Africa. Again, I was in Cederberg. Again we were staying in the type of accommodation that makes biologists “oooh” and “ahhh” and walk around, poking into corners with a junky’s avarice. Make no mistake- Cederberg is one of my favorite spots on the planet. It’s gorgeous and fascinating. It just needs some screens, and I’ll tell you why…
One evening, as the entomologists set out to see what could be found in the darkened crevices of the mountains, I deferred, pulled a couple of chairs to the middle of the verandah, poured some wine, made a snack plate, put my feet up, and opened a book.
It wasn’t long, maybe only a half hour of sipping, reading, nibbling, and pausing to feel the warmth of everything right, before things changed. A cat emerged from an unlit corner and as I leaned forward with an “Oh, hey kit…tie…”, I saw that it was stalking something. A mouse? I thought hopefully, naively. No, this was Africa. The cat was not chasing a mouse. What it was batting at looked like a mouse, to be sure. A large, bleached mouse that began to run like the wind. I froze, recalling platitudes- it’s more scared of me than I am of it; it wants to avoid me; it won’t climb my chair, or the walls, then lose its grip on the ceiling and fall down the back of my shirt collar…
As I was trying to calm myself with this mantra, the solifugid raced directly to my chair, and attempted to climb a leg. I jumped to stand on the chair- though, I couldn’t but note, nowhere near as quickly as the solifugid was moving. Supposedly, they can run over 6 inches per second, which earned them one of their common monikers- wind spiders- but I’m here to insist that when feral cats are chasing them, they easily set new PR’s.

A storm passes over the top of a mountain in Cederberg at the end of a scorchingly hot day. This place is worth every degree and every arachnid above my comfort level. [Canon 7D, Canon 14mm]

A storm passes over the top of a mountain in Cederberg at the end of a scorchingly hot day. This place is worth every degree and every arachnid above my comfort level. [Canon 7D, Canon 14mm]

The cat was in hot pursuit, so rather than struggle to grip my chair legs and race up to tangle itself in my hair, the solifugid bolted to another dark corner of the porch. Other than seeing the shadowy figure of the cat racing and pouncing, I had no idea where it was. I looked behind me at the door to our chalet. It wasn’t more than 3 feet away, but I didn’t feel confident that I could make it before the solifugid did, wherever it was.

Then suddenly, there it was, scrambling up the side of the wall and toward me without losing any of its breakneck speed, the cat trailing it along the floor. I may have screamed, I don’t know. What I do remember was cursing Piotr in my head- while trying to convince me that there was no need to sleep in the car during that first encounter, at the Spider Chalet, he had absentmindedly assured me not to worry, the solifugid wouldn’t climb anything. It was said with the distracted air of a man telling his wife that yes, he has noticed her haircut and likes it, so I should have known better.

Glorious Cederberg. [Canon 7D, Canon 14mm]

Glorious Cederberg. [Canon 7D, Canon 14mm]

As it passed over the door and zoomed back toward the floor, I knew that I had to act. I jumped from the chair and made for the door. The solifugid reversed course and came straight for me. I jumped back up on the chair (I learned later, when relaying this story to Piotr, who seemed to see it more from the solifugid’s perspective than mine, that they seek safety in shadow, and the shadow that I cast as I moved, intent on my own escape, made me an unwitting attractant.)
Confused, it turned to dart back toward the shadows again, and this moment’s hesitation allowed the cat to get a good whack in. The solifugid reared up and presented the cat with its enormous, open jaws, and lunged. The cat jumped backed, stunned and impressed. With another lunge for good measure, the solifugid took advantage of the cat’s reverence for its display and zipped into the dark. The cat followed, slowly- back in stalking mode- and I made my second jump from the chair, frantically fumbled the door open, and burst into the cabin, eyeing the gap fretfully and wondering why it wasn’t a priority anywhere in Cederberg to fashion doors to meet the ground.

I sat in the middle of my bed and aimed my headlamp like a sentry at the screenless window, which opened directly onto the verandah that I had just fled, and waited for the others to return from their night collecting. I tried to shut the window, but the heat was unbearable. After a day of baking at well over 114F in the sun, the cabin needed all night to cool down. Hours passed. Finally, I laid back. I opened a nearby book and exhaled. Cue something, of course. It was the cat, jumping in the window. Why? On the tail of the solifugid again? Why else would it have come in? This is what I had to assume. War rules.

I will never know if the cat, which soon exited through the kitchen, came in because it was chasing something. But what I do know is that entomologists can stay out in the dark for eons and, when they return in their exultant state, don’t think to wonder about overturned chairs, scattered snacks, and splayed books in the middle of the porch. They walk right by with their containers and baggies held up for rapturous inspection, like urbanites immersed in their cell phones, and seem startled to see you awake and upright, just before dawn- “Oh, hey baby- what are you doing up?”

Compared to a solifugid, this tiger spider (Argiope australis) seems like sweet, harmless bunny. [Canon G10]

Compared to a solifugid, this tiger spider (Argiope australis) seems like a sweet, harmless bunny. [Canon G10]