Island Biodiversity Race

Category: Biodiversity, Sao Tome, frogs, mushrooms, shrews | Date: Aug 18 2009 | By: islandbiodiversityrace

Ever wonder why biologists use weird, hard-to-pronounce names for animal and plant species?  Well, it all started with Carl Linnaeus, the famous Swedish 18^th Century botanist pictured below.

In the 10^th edition of his great work, Systema Naturae (1758), Linnaeus established a system  wherein  every living species is given but a single scientific name made up of two parts: the Genus (always capitalized) and the species (always lower case and both are always italicized).  Among animals, no two species ever have the same name, and this is true among plants, as well.  Thus we modern humans are scientifically referred to only as Homo sapiens.  In Linnaeus’s day, most scientists wrote in Latin or Greek, thus it was an early tradition to establish these names in those ancient languages.  Now, naming of new species is tightly regulated by The International Congress of Zoological Nomenclature (ICZN; the botanists have the ICBN).  A specific scientific name avoids confusion… here is an example:

The common English name of the critter above is red rattlesnake, or red diamondback rattlesnake; some locals might call it a “red buzzworm!”  In French it would be called un serpent á  sonnettes rouge;  in German: eine rote klapperschlange and if an East African ever saw one, he might call it nyoka sumu nyukundu.  See the problem?  Not only different base languages, but regional differences in common names serve to muddy the waters.  However, the scientific name of this critter is Crotalus ruber, and regardless of their native languages, scientists will always know exactly what species is being discussed.  Taxonomists usually try to come up with a name that is descriptive of the species; in this case, Crotalus ruber translates roughly from the Latin as “red bell-ringer,” an obvious reference to its color and the sound made by the rattle.

The Sao Tome shrew: Crocidura thomensis (R. Lima phot, 2009)

Here is another example– the supposedly endemic shrew we are just beginning to study is called Crocidura thomensis, which means “yellow-tail from Thomas [=São Tomé]”.  Probably the first species described in the genus Crocidura had a yellowish tail, although C. thomensis clearly does not.

The Oceanic Treefrog, Hyperolius molleri (Weckerphoto GG III)

Scientists may also name species in honor of the person who first collected the specimen; such is the case with the Oceanic treefrog, Hyperolius molleri, found on both São Tomé and Príncipe, M.A.F. Moller was the late 19^th Century explorer who first collected the frogs and brought them to Portugal where the species was named in his honor at the University of Coimbra.

Sao Tome puddlefrog, Phrynobatrachus leveleve  (Weckerphoto GG III0

Taxonomists have a fair amount of latitude in the choice of words and meanings for scientific names although they are usually Latinized.  As an example, Josef Uyeda, Breda Zimkus and I chose Phrynobatrachus leveleve as the new name for one of our own new species of frogs from São Tomé.  Phrynobatrachus is an old generic name and actually means “toad-frog;” as to the meaning of leveleve, here is a quote from our paper:  The phrase, “leve leve,” generally meaning “easy, easy” or “lightly, lightly” has also been translated by Henrique Pinto da Costa, former Minister of Agriculture, as “calmly, surely.” In our opinion, all three definitions describe the delightful, easy-going demeanor of the citizens of The Republic of São Tomé and Príncipe….it is with the hope that the citizens of this tiny African nation will maintain their ecological heritage and cheerful outlook on life that we name this diminutive endemic anuran. Thus, we named the new species in honor of the attitude of the island citizens.

Illustration by H. Heatwole, 1970

Scientists are also known to inject humor into scientific names, on occasion. The image above is a composite plate from a scientific publication.  By way of explanation, many American scientists receive support for their work from our National Science foundation, known universally to us over here as “NSF”.  Look at the upper-most image of a frog known scientifically as Physalaemus enesefae… if you are an English speaker, pronounce the species name slowly and you’ll get the humor.

Now for the fun stuff: here is a photo of our latest new species from São Tomé, a mushroom we discovered on the trail up to Lagoa Ameliaduring GG II in 2006.  It was formally described just last month in the journal MYCOLOGIA,  and Drs Dennis Desjardin and Brian Perry named it after me.   It is called Phallus drewesi meaning (literally) Drewes’s penis!

Phallus drewesi Desjardin & Perry 2009 (B. Perry phot. GG III)

As you can see, these fungi are shaped very much like a mammalian penis… they usually grow upright from the forest floor, smell terrible and attract flies! The flies act as vectors disperse the fungus’s spores!

Dr. Brian Perry with a Principe Phallus  (RCD phot. GG III)

Members of the genus Phallus can grow quite large. Above is an image of Dr. Brian Perry, one of the describers, holding an example of Phallus atrovolvatus from Príncipe –a rather average sized Phallus.

The author with Phallus drewesi on Sao Tome  (Weckerphoto, GG III)

Above is a picture of me holding a couple of examples of Phallus drewesi in 2008, and as you can see, they are quite small!  Not only that, but so far as is known P. drewesi is the second smallest species in the world!  And, it grows limp! Not proudly erect from the forest floor!

It has been hard for some of my non-scientists to understand what an incredible honor this is.  Dennis, Brian and I are good friends and colleagues; in fact, Dennis and I play jazz together as often as we can and serve on the same university faculty.

The author and Dr. Desjardin at Praia Francesa. (Weckerphoto GG III)

It is a great honor because having a species named for you confers a form of immortality. Regardless of what the species is, the scientific name lives on as long as there is science. This is even the case even if decades from now, another scientist learns that this species already has a name – Phallus drewesi lives on in the botanical literature as a synonym. Scientists keep track of all names formally ascribed to a species, whether valid or not.  So, yes, it is a wonderful thing to have something named after you, whatever it may be!

Here’s the parting shot:

PARTNERS

We gratefully acknowledge the support of the G. Lindsay Field Research Fund, Hagey Research Venture Fund of the California Academy of Sciences, the Société de Conservation et Développement (SCD) for logistics, ground transportation and lodging, STePUP of Sao Tome http://www.stepup.st/, Arlindo de Ceita Carvalho, Director General, and Victor Bomfim, Salvador Sousa Pontes and Danilo Bardero of the Ministry of Environment, Republic of São Tomé and Príncipe for permission to export specimens for study, and the continued support of Bastien Loloumb of Monte Pico and Faustino Oliviera, Director of the botanical garden at Bom Sucesso. Special thanks for the generosity of private individuals, George G. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke and Mr. and Mrs. Michael Murakami for helping make these expeditions possible.

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Category: Biodiversity, Gulf of Guinea, Island endemics, Sao Tome, frogs, gigantism, principe | Date: Dec 15 2008 | By: islandbiodiversityrace

 Sorry, I love titles like this… and I have more!  Actually, there are no toads (Bufonidae) on São Tomé and Príncipe; interesting in itself because seven other amphibian species of five different families have survived the ocean crossing during the many millions of years since the islands first emerged. Moreover, toads are common in almost every  conceivable terrestrial mainland habitat.  

My last two blogs have been a bit academic.  Having laid the biogeographical ground work, it is probably time to get back to the unique, endemic island critters.   The tiny, 31-million year old island of Príncipe is the only home of Africa’s largest treefrog, Leptopelis palmatus – the Príncipe Giant Treefrog.  It is one of the world’s rarest frogs, as well.

 L. palmatus – D. Lin phot. GG I 

Let me be quick to point out that the Príncipe critter is not Africa’s largest frog; that title belongs to Conraua goliath (below), which is found on the mainland in southern Cameroon and Gabon.  In fact, the goliath frog is the largest in the world but it is not related to any on São Tomé and Príncipe– no members of its family have made it across the saltwater gap to the islands, or if they ever did, they have not survived. 

Conraua goliath—J.-L. Perret phot. 

Leptopelis palmatus is the largest African treefrog (emphasis on “tree”) — frogs that are adapted for climbing with, among other features, enlarged finger and toepads.  As I have pointed out in earlier blogs, gigantism is a relative thing; the giant endemic plants, frogs, birds and lizards of São Tomé and Príncipe are bigger than all of their relatives but they are not necessarily so large you trip over them (like Galapagos or Aldabra tortoises); they are simply larger than all of their relatives.  The two images below put this frog in some perspective, and I think you will agree that this is one BIG treefrog. 

Me, with the first female. R. Stoelting phot. GG I 

The frog on Dong Lin, our photographer.  R. Stoelting phot GG I

This species was first described in 1868 on the basis of a single female specimen, housed in the Berlin Museum. At the time of GG I in 2001, the Príncipe giant treefrog was known only from this single type specimen and seven additional specimens, all females, collected by local Príncipeans for a Swiss colleague named Catherine Loumont.  The largest of Loumont’s specimens is 110 mm from snout to vent (we do not include legs when we measure frog sizes), and even after our years of work, this specimen remains the largest ever found – it is nearly 30 mm longer than the largest of its nearest mainland relative, Leptopelis macrotis, distributed from central Sierra Leone to Ghana. One of several differences between the two species is the striking deep-red eyes of our island endemic. 

The eye of the Príncipe giant treefrog. D. Lin phot. GG II 

This first specimen we found during GG I (first three treefrog images, above) was yet another female, 108 mm in length.  Our mammalogist, Doug Long, was led to the critter by some kids from the now-defunct plantation of Sundi in northwest Príncipe. Sundi may no longer function as a plantation but it is still inhabited by the descendents of former workers—lots of them, there is even a mayor. 

Doug Long and the Sundi kids. RCD phot. GG I 

The arrival of this frog was greeted with great enthusiasm by yours truly; here in my hands one of the rarest frogs in the world! And it was huge! I was not surprised to learn that it had been found on the ground, as it is hard to imagine something so bulky climbing around in bushes and trees. The male of this species was completely unknown, so far as we knew at the time,.  None had ever been collected, photographed nor described in the scientific literature.  So we also knew nothing about the species’ breeding biology, male advertisement call or tadpole.  At the time, we were unaware of a blog posted two years before our visit by Jonathan Bailey on the Gulf of Guinea Conservation Group website, entitled “One month in the Forest of  Príncipe.” Jonathan (now Dr.) Baillie described hearing the calls of male L. palmatus as “like a pop bottle being continuously opened.”  He heard them high up on Pico do Príncipe near a small stream at about 700 m and actually collected two of them which had been deposited in the Natural History Museum in London.  But during GG I, the male giant treefrog was terra incognita, so far as we were concerned.  

Second female from Rio Papagaio.  J. Ledford phot..  GG I 

During a second GG I visit to Príncipe a few weeks later, my then-graduate student,  Ricka Stoelting, collected another female along the Rio Papagaio, a large-ish river that flows through Príncipe’s only town, Santo Antonio.  It was also of a rather dull in color but with white spots. We have since learned that this is about as brightly colored as females get. 

Rio Papagaio in town, downstream. RCD phot. GG III

Ricka Stoelting, my graduate student on Sao Tome.  RCD phot. GG I.  

During this second visit, Ricka and Dr. Sarah Spaulding ascended Pico do Príncipe to the top and camped at nearly the same spot where Jonathan Baillie had been two years before.  There she found the males, lots of them, calling from bushes and branches at night near a very small creek.  

Tiny creek on the Pico.  J. Uyeda phot. GG II

 Ricka brought the series of males back down the mountain, and they were astounding.  Unlike the females they were very brightly colored and highly variable, in pattern, as well; this variability is rather unusual in frogs, although there are some species that are sexually dimorphic for color. And they were much, much smaller than the females, though we knew they were full-sized breeding adults. During later analysis we learned that the largest breeding males are only about 41% of the size of the largest females, a size disparity that is striking.

First series of live males (far right is a juvenile).  J. Ledford phot. GG I

  Ricka never heard them calling and anyway she had no way of recording them if they had.  One of the parameters we use in establishing relationships among frog species is analysis of the voice (or advertisement call.). Males call to attract females, and at the same time to advertise their presence and territory to other males.  The advertisement call is species- specific and obviously adaptive when there are other species utilizing the same water for breeding.   To really define Leptopelis palmatus, I needed a recording of the voice, and this was to become a priority in the future. Below is a preliminary analysis of the call of another Gulf of Guinea frog species which we think is present on both islands.  Here, we are comparing the advertisement calls of males from two different localities on both islands, and we can see that they are basically the same.

 Preliminary sonograms of Oceanic treefrog. Marshall/Drewes construct.  

 Back at the Academy, Ricka and I prepared the first formal description of male Príncipe giant treefrogs.  Now aware of Baillie’s blog, we read his word description of the advertisement call.  Although the Principeans insisted the frogs did call, it remained an open question, especially when I learned from anatomical study that the male frogs  lack vocal sacs and vocal sac openings, features that most calling frogs possess (including other members of the genus Leptopelis).   GG II in 2006 included Josef Uyeda as my student (now a PhD candidate at Oregon State University).  Josef was working on a different group of island endemics called puddlefrogs (see earlier blog: “We Find Jita”) but when we were on Príncipe, I sent him up the Pico with his friend Mac and the same guide, Manona, who had led Jonathan Baillie and Ricka years before. They were armed with my old Sony cassette recorder (my iPod had failed).  Bear in mind that the only known localities for males were at nearly 700 m, high on the Pico and while this made no biological sense, that’s where my stalwarts had to go. This is no small matter given the topography of the island, but graduate students are good at this sort of thing and anyway, they tend to be younger and more vigorous than their advisors!

Principe terrain. Pico do Príncipe is in the clouds to the left of the large Pico Papagaio. R. Wenk phot. GG III

 Josef Uyeda hunting for caecilians on São Tomé. D. Lin phot. GG II  

While in the same general area as earlier workers at about 700 m, Josef got a lot done but the party was caught in heavy rains.  He heard males and saw them calling but only managed some rather distant, poor-quality recordings (the conditions were miserable), but now at least we knew that the frogs did, indeed, call.  GG III, last spring, provided some answers, thanks in part to our friend Ramos of Bom Bom Island.  Ramos is assistant manager of the resort, a native Principean and a keen, observant naturalist.  See the photo of Ramos in the “We Find Jita” blog.  I described our past difficulties in trying to record the voice of the Príncipe giant treefrog to him, and he grinned and said, We will go to my roça (farm) on Pico Papagaio and at 5:30, we will get them!  I was highly skeptical…

Roça Papagaio, Ramos’s farm at 250 m. R. Wenk phot. GG III 

Ramos’s farm is in the forested area on the northern flanks of Pico Papagaio at about 250 m.  Just before you reach it on a dirt steep uphill road, you cross a tiny creek; this is where Ramos took us –  about 30 m up that small creek, thick with dense undergrowth, and there we sat, waiting for the forest cacophony of grey parrots, mona monkeys to subside.  Nothing much happened.  I had my iPod with recording head at the ready.  We waited in the gathering gloom for about 20, maybe 30 minutes, Ramos grinning throughout and occasionally exclaiming,  Just wait. We will get them! 

Me waiting, iPod in hand, for the giants to call.  T. Daniel phot GG III 

And sure enough, we began to hear frogs calling. I looked at my watch. It was 5:30. The call is certainly a strange one; it lacks resonance (remember males don’t have a vocal sac) and thus it is rather flat and unmelodius. Rather than my trying to describe it or arguing with earlier descriptions, you can listen to it yourself by clicking this link: 

Click here to listen

And here are a couple of photos of the male that was calling, taken by Wes. These are un-posed and taken before we collected it as a voucher specimen for the voice:

 Weckerphoto GG III

 Weckerphoto - GG III 

There are still great gaps in our knowledge of this most unique frog.  Obviously, the males are well-distributed in the lower elevations; we just have not been in right place at the right time.  We still cannot explain why females are dull and rather cryptic in coloration and usually found on the ground, while there appears to be no selection for color in males.  The dull color of females seems consistent, as a couple of months ago I found six additional females (no males) collected in 1988 at the Doñana Institute in Seville and they were clearly drab in life; my colleagues at Donana tell me they were collected on the ground in lowland localities at Rio Papagaio and Bela Vista.

Six female Seville specimens at Donana Institute.  RCD phot. 

We still have not observed breeding, nor have we ever seen tadpoles.  In this genus, Leptopelis, they are very distinctive, and I would predict the tadpole will look like this: 

A Leptopelis tadpole. Image courtesy of Dr. R. Altig 

Here’s the parting shot: 

Nezo, of Angolares, Sao Tome: artist, musician, restaurateur and worthy man - Weckerphoto GG III

PARTNERS We gratefully acknowledge the support of the G. Lindsay Field Research Fund,  Academy Research Venture Fund of the California Academy of Sciences, the Société de Conservation et Développement  (SCD) for logistics, ground transportation and lodging, STePUP of Sao Tome http://www.stepup.st/, Arlindo de Ceita Carvalho, Director General, and Victor Bomfim, Salvador Sousa Pontes and Danilo Bardero  of the Ministry of Environment, Republic of Sao Tome and Principe for permission to export specimens for study, and the continued support of Bastien Loloumb of Monte Pico and Faustino Oliviera, Director of the botanical garden at Bom Sucesso. Special thanks for the generosity of four private individuals, George F. Breed, Gerry F. Ohrstrom, Timothy M. Muller and Mrs. W. H. V. Brooke for making these expeditions possible.          

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Category: Biodiversity, Gulf of Guinea, Island endemics, Sao Tome, frogs, gigantism, principe, snakes | Date: May 27 2008 | By: islandbiodiversityrace

Scientists love islands because the processes of evolution on islands are simpler than they are on more complex, much larger continents and thus more easily studied. I have made the point that the islands of Sao Tome and Principe are very poorly known, but what we do know is very exciting. One evolutionary pattern that seems to consistently appear on islands is the phenomenon of gigantism; for some reason certain successful colonizers become very large on islands: for instance, think of the tortoises on the Galapagos Ids. or on Aladabra. There are a number of hypotheses that attempt to explain this phenomenon, but none is particularly compelling; nevertheless, the pattern exists and is very evident on the oceanic Gulf of Guinea Islands. The composite image below illustrates just a few of the giants on Sao Tome and Principe.

Some Island Giants

Think of potted plants for a moment… how large is a begonia? The central plant in this composite image is the largest species in the world, Begonia baccata. It is found only on the island of Sao Tome and reaches 10 meters in height! This particular specimen graces the southern shore of Lagoa Amelia at about 1480 m elevation - my head comes up to about flower level on this old friend (I am 6′ tall); these enormous plants are common at higher levels. The two birds figured are also giants: the yellow one on the right is the world’s largest weaver. Ploceus grandis,. and the one on the left is the world’s largest sunbird, Dreptes thomensis; both endemic to the larger island of Sao Tome. This is a good point at which to mention that island dwarfism is also an observable phenomenon  here as well, and the world’s smallest ibis, the Sao Tome Dwarf Ibis, Bostrychia bocagei is also an endemic.  The other critters in the collage, the frogs and the lizards, are all endemic giants but I will deal with them later. It is important to bear in mind that when we call a species a “giant”, we are describing its size compared to all of its other relatives only; such a species may not appear to be a giant at all, in our eyes.

The Sao Tome Giant Treefrog, Hyperolius thomensis, and I go back a long way; back to when I was writing my doctoral dissertation many years ago. This sapo (as all frogs are called on the islands) is endemic to Sao Tome only and is easily the largest member of its genus (Hyperolius)- females reach lengths of nearly 50 mm.from snout to vent!

Sao Tome Giant Treefrog, Hyperolius thomensis.GG I and GG II - D. Lin

Nearly all of the original material from which this species was described in 1886 was destroyed in the fire in Lisbon.  But I managed to find four remaining specimens, two in Vienna and two at the Natural History Museum in Vienna, allowing me to treat them in my dissertation.  In 1988 and again 1990 more specimens were reported by a Swiss worker, but her published locality data are very general, if not vague, and it turns out that most of the material she worked on was collected by locals at her request prior to her arrival.  During GG I, we visited most of her reported localities, finding nothing until we finally got lucky. Now, I can state that this most flamboyant of treefrogs is currently known for certain from only a single locality!  Our work in GG I, II and III has confirmed that this marvelous critter is known only from higher elevations (above 1000 m), inhabiting the canopy of old secondary or primary growth trees on steep slopes.  And it appears to breed only in the water-filled holes in trees with fluted bark or buttresses.  This is a rarity – in Africa, only 9 other frog species are known to breed in phytotelmata (scientific word for treehole). But it makes sense.  Most frogs lay eggs, which develop into free-swimming, gilled tadpoles, which then metamorphose.  Although there are many fast moving rivers on the steep slopes of Sao Tome, these are far to swift for breeding; still bodies of water simply do not exist. So, H. thomensis has adapted to breeding in ephemeral, rain-filled holes in the trunks of very large trees! All of the other frogs native to the islands utilize slow moving or still water for reproduction.

The tree - J. Clara, GG III

This is the only tree in which we have collected the Sao Tome Giant treefrog.  It is at about 1100 m on a high ridge, and we return each expedition to check its status. Adults are usually present but there are always eggs and tadpoles at different stages of development in the holes.  Tom and Rebecca, our botanists, could not identify this tree – it is simply too tall its see its canopy, and moreover it is festooned with epiphytes.

Frogs and eggs in treeholes -  WE, GG III

Wes Eckerman, our photographer tried to climb it, and then tried to climb an adjacent tree to see if there were more holes, but the tree is just too big in girth to handle; with our friend Jose Clara, we tried to erect a crude ladder to examine a hole farther up the trunk but to no avail.

RCD, GG III

I do not mean to imply that this species is restricted to this tree.  We have heard the species calling at night from high up in the canopy and reasonably certain that it is pretty widespread, at least in the high elevation forests we have visited – I suspect it is present on Sao Tome anywhere the trees are large enough and that. of course.  means upslope above the former Portuguese plantations.  What is different about this single documented tree is that it is the only one whose rain-filled holes are within our reach – there are undoubtedly more holes in many more trees that are too high for us to access.  I am left with the notion that given its restricted range and peculiar breeding biology, the Sao Tome Giant Treefrog is a classic indicator species; its presence means healthy mature forest.  If I were to choose an icon to symbolize the dogged persistence of pockets of nature in the face of man’s depredations and at the same time the attitude, beauty and whimsy of the citizens of Sao Tome and Principe, it would be this gorgeous island giant. Josef, my former student, informs me that he has already seen the name of this species on a price list in the pet trade in Europe.  If you  wonder why I have not described the location of this tree is in more detail, now you know. 

In the last posting, I promised you a picture of the cobra jita of Sao Tome. Here are shots of both island forms, which are currently considered to be the same species.

Sao Tome Jita - RCD, GG I

Principe Jita - WE, GG III

Not only do these critters look different from those on Sao Tome (stripes vs. patterned blotches), they act differently as well. On Sao Tome, cobra jita appears to be strictly nocturnal; during GG I and GG II we easily found them at night by first listening for the loud choruses of oceanic treefrogs (more about them later). So far as we know, the Sao Tome jita largely feeds on these frogs while they are breeding and is strictly nocturnal; to see at least ten of these snakes in a single night under the right conditions is not uncommon.

R. Stoelting, my grad student, with her first Jita - GG I, RCD phot. After our week on Principe, however, I am prepared to say that that jita is diurnal and although we will not know until we check stomachs, I think it feeds on lizards and small rodents. We even located a chorus of treefrogs behind Bombom but failed find a jita, nor did we ever find one during our night hunts. Only time and careful study of morphology nd DNA will tell us how closely related these two island snakes really are.Thanks to Caitlin D. for her generous donation. We are doing what we can!

PARTNERS We gratefully acknowledge the support of the Research Investment Fund of the California Academy of Sciences, the Société de Conservation et Développement  (SCD) for logistics, ground transportation and lodging, STePUP of Sao Tome http://www.stepup.st/ and especially the generosity of three private individuals, George F. Breed, Gerry F. Ohrstrom and Timothy M. Muller, for making GG III possible.

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Category: Biodiversity, Gulf of Guinea, Sao Tome, biogeography, frogs, principe, snakes | Date: May 03 2008 | By: islandbiodiversityrace

We are still on Principe and down to the hard corps: me, Wes and Josef. The mushroom and plant folks, Dennis, Brian, Tom and Rebecca are home in San Francisco by now. So it is time to tell you a little about my own research interests. Cobra Jita is a snake and we have been looking for it all week; in order to explain why, I need to tell you a frog story.

Josef Uyeda on Principe. Weckerphoto GGIII

As I have said, the fact that there are amphibians here at all is astounding; amphibians, along with primary freshwater fish, are among the poorest dispersers across saltwater barriers known. They are the last kinds of critters one would expect to find on an oceanic island…. Think of the Hawaiian Islands and the Galapagos, perhaps the two most intensely studied oceanic archipelagos in the world… no frogs or other amphibians, right? But here on Sao Tome and Principe we have seven amphibian species, one of which is the famous caecilian, Schistometopum thomense. How can this be? How did they get here? More on this later, but one of the keys is time: remember that Sao Tome is at least 15 million years old, and Principe is more than double that, perhaps 31 million years. Hawaii and the Galapagos are but 5 million years max.

During GG I, we collected series of little brown frogs of the genus Phrynobatrachus from various locations on both islands; at the time all of them were considered the same species, P. dispar, originally described from Principe over 100 years ago. In 2005, a bright young intern from Willamette University named Josef Uyeda, spent the summer in my lab studying these preserved specimens and concluded that the frogs were quite different. Josef joined GG II and did a lot of collecting on both islands, recorded calls, did dissections and comparisons of DNA from the critters on both islands. The results are that the two island frogs are VERY different; in fact, there is nearly 21% DNA sequence difference between the two; indicating that they have not interbred in many millions of years, possibly predating the existence of Sao Tome (yet they still look virtually identical!). Moreover the two together appear to be more closely related to East African species than to more nearby West African species, but more on that later. In 2007, Josef, I and Breda Zimkus of Harvard described the Sao Tome brown frogs as a new species, Phrynobatrachus leveleve.

Phrynobatrachus leveleve. Sao Tome. Weckerphoto GGIII

Phrynobatrachus dispar Principe. Weckerphoto GGIII

from Uyeda et al. 2007. Proc. Calif. Acad. Sci. 58

This brings me to cobra jita (pronounced “zheetah” – it means snake slow, as opposed to the other Principe snake, cobra sua sua, which means snake fast!). Here we have the same situation as we had with the small brown frogs, Phrynobatrachus. Jita (more properly known as Lamprophis lineatus bedriagae, or lined house snake) has always been considered to be the same species on both islands. After our frog studies, I am not so sure! They look different – regrettably I will have to post a picture of the Sao Tome form later… didn’t bring one in my zip drive—the Principe form is much more obviously patterned than the Sao Tome snake. During GG I and GG II we got very good samples of the Sao Tome population, but for some reason, only one specimen from Principe.

Lamprophis from Bombom Id, Principe. Weckerphoto GGIII

Lamprophis from Sao Tome. D. Lin photo. GGII

Josef is now a PhD candidate at Oregon State University and joined us a couple of weeks ago in our search for Jita (among other things I will describe later). Snakes, as you probably know, are where you find them… as primary predators, they are never very common but always around, and such has been the case here on Principe. It has taken us six days of trekking around in the forest, turning over logs, etc. to find six snakes. But I am delighted. This is certainly enough now to estimate the genetic distance between the two populations, and given the age of these islands, I will not be surprised at all to learn that they are distinct at the species level.

Josef and I looking for Jita on Bombom Id. Weckerphoto. GGIII

We have learned a lot about this critter. On Sao Tome, Jita is primarily nocturnal while the daylight hours on that island seem to be dominated by the endemic Sao Tome green bush snake, Philothamnus thomensis. This is the situation we would predict using island biogeographic theory—no niche overlap – they both seem to eat frogs and skinks, but at different times. But here on Principe, all of the jitas we have caught have been during the daylight hours, as was the single individual caught during GG II in 2006. Moreover, the green snake of Principe (yes there is a green sua sua here as well, but not related to the Sao Tome species) also seems to be diurnal! They are incredibly fast; we have seen two of them and missed both. So until we can look at stomach contents, we seem to have an ecological mystery.

Me, Josef and Ramos on Bombom Id. Weckerphoto GGIII

Our search has been greatly aided by an amazingly bright local naturalist; Jose Ramos Maria Vital Pires, or Ramos for short. Ramos has led us around this island searching for the elusive jita we have been blown away by his keen perception and observations of the local flora and fauna, and his delightful smile and sense of humor. The thing is everyone knows about this snake, most of the locals are to say the least, not exactly fond of snakes and one referred to as a “house snake” frequently comes a little too close for comfort, as you might imagine. But finding a snake when you are looking for it is entirely different matter. Our first success occurred on Bom Bom Island (not really and island, but sort of). I had just commented that the area Ramos was leading us through was too steep to find a snake, when he began excitedly shouting “snake!” only meters away. Within moments we had bagged our first jita.

There have been some rather ignominious moments for me personally. My two young compadres, Wes and Josef are willing to give me credit for catching but one jita, a dead one. The specimen had, in fact, been killed two hours earlier by a local woman who was delighted to have us remove it from along the road. This morning was the last straw. We had been combing Bom Bom Island again; Josef and Wes had taken a lower route than I and about an hour in, I heard Josef yell that they had caught a snake in the act of ripping a tail off a skink. Well and good, I thought, but where’s mine? So I am walking along, seeing snake food like skinks all over the place, when Wes and Josef come down the trail towards me. We stopped, admired the snake Josef had already bagged and the photos Wes took of it eating its skink tail, all three of us turned around…Josef stooped over and grabbed our largest jita of the expedition, about a foot behind me. I must have stepped right over it a moment beforehand. Perhaps it is not necessary to tell you that there has been much snickering among the younger members of this outfit ever since… Argh.

Josef collecting a jita on Bombom. Weckerphoto GGIII

Nova Cuba, near Santo Antonio, Principe. Weckerphoto GGIII

PARTNERS We gratefully acknowledge the support of the Research Investment Fund of the California Academy of Sciences, the Société de Conservation et Développement  (SCD) for logistics, ground transportation and lodging, STePUP of Sao Tome http://www.stepup.st/ and especially the generosity of three private individuals, George F. Breed, Gerry F. Ohrstrom and Timothy M. Muller, for making GG III possible. More anon.

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