Island Biodiversity Race

Category: Biodiversity, Gulf of Guinea, Island endemics, Sao Tome, barnacles, centipedes, coral, invertebrates, principe, snakes | Date: Nov 20 2009 | By: islandbiodiversityrace

It has been a busy couple of months, hence no posts on THE RACE.  In my last one, I hope I made it clear that scientists have senses of humor (my favorite ones do, anyway).  Here’s another fact you might not know; regardless of what he or she studies, there is probably not a single field biologist anywhere who does not have a secret dislike or even fear of one sort of critter or another.  With me, it has always been centipedes– even when I was a child.  I can’t bear the things!  And, naturally, there are some real monsters common on São Tomé.  The creatures in the shots below are about 10 inches long, sometimes they get larger!

Scolopendra subspinipes. D. Lin phot. GG II

S. subspinipes - Weckerphoto, GG III

These arthropods are more properly known as scolopendras, and they are voracious predators; the upper one is devouring a slug.  The two above are Scolopendra subspinipes, are native to Southeast Asia and thought to have been brought to the islands accidentally.  The Academy was just visited by Dr. Rowland Shelley, a specialist on millipedes from the North Carolina State Museum, who had a look at some of our critters.  He and his colleague, Dr. John Lewis of the UK identified these but, more exciting, the one pictured below.

Otostigmus productus DLin phot- GG II

This is a different species that was originally described from São Tomé over 120 years ago.  It is thought to also occur in West Africa; if this is the case, O. productus  is not an endemic species but it is probably naturally occurring.

Photo shoot on Sao Tome. Dong Lin, Fabio Penny and Ricka Stoelting -RCD GGI

Ricka Stoelting (above at right), my grad student and GG I participant, is putting the finishing touches on her manuscript on the fabulous São Tomé, “cobra bobo.” After submitting it for publication, she will pursue her PhD at the University of Wisconsin.

Schistometopum thomense - Weckerphoto, GG III

Ricka’s research has shown that this remarkable legless amphibian, Schistometopum thomense is indeed a true endemic species, having gotten to the island by natural means.  By studying the genetics of these bright yellow burrowers, she has learned that there are two different genetic groupings of the caecilian on the island and this is possibly related to volcanic activity within the last million years.

Principe Jita. Lamprophis sp. Weckerphoto GG III

Our snake project on “cobra jita” (Lamprophis - see earlier blogs) is ongoing; my intern, Lisette Arellano (above) has returned from the University of California, Santa Barbara and is working down in our molecular lab as I write.  Last summer we learned that although they are very similar in appearance, the snakes on São Tomé and Príncipe are genetically distinct from one another based on Lisette’s analysis of the cytochrome b gene.  We think that analysis of an additional nuclear gene will be useful.

Lisette Arellano at the Academy.  RCD

The big issue lies with the status of jita’s relatives on the mainland.  While we are now reasonably sure that the two island populations are separate species, we do not know what their relationships are to the at least 12 species of Lamprophis distributed widely in Africa; it is possible that either or both of our island snakes could belong to one these mainland species. Unfortunately  the relationships (systematics) of this whole group in Africa are poorly understood.  Dr. Chris Kelly of Rhodes University who is working on the entire complex has kindly sent us a number of tissue samples of Lamprophis from some West African localities, and these are what Lisette is analyzing now.  In June, Lisette is off to the University of Colorado to pursue her PhD.  Hopefully, we will have figured out our island snakes by then.

Dana Carrison off Principe.  Pola-Perez phot.  GG III B

Dana Carrison is an MSc candidate at San Francisco State University and was part of marine phase of GG III (see Send In the Marines).  She is the graduate student of Dr. Bob Van Syoc, a participant of both GG II and III marine expeditions.  Dana is nearing completion of her research on the barnacles she and Bob study and has this to say:

“So my latest findings are that we have not one, but two new species from the Gulf of Guinea. They are both found on Principe and Sao Tome. One only settles and lives on one species of gorgonian and the other is found on many different species of gorgonian. My DNA analyses are pretty much finished and they’re very agreeable.”

I should mention that the gorgonians to which Dana refers are studied by Dr. Gary Williams, also a Gulf of Guinea veteran of two expeditions.  Here are Dana’s new species:

Conopea new species #1   phot. D. Carrison

Conopea new species #2  D. Carrison phot

More anon and before our return to the islands.

Here’s the parting shot:

Chaplin, Executive Director, BomBom Island, Principe. Weckerphoto GG III

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, Uncategorized, barnacles, biogeography, coral, invertebrates, principe | Date: Feb 20 2009 | By: islandbiodiversityrace

I have just heard that Alex Kim, the student at Thomas Jefferson High School of Science and Technology in Virginia has received the new freshwater prawns GG III (B) collected for him and is in the process of extracting DNA from the fresh tissues. As I mentioned in the last couple of blogs, Alex is a finalist in the Intel Science Talent Search, and we are very interested in his progress.  His results will add to our understanding of our own work and the biodiversity of these islands.  When Alex first contacted me, I had some concern that we might have neglected to bring prawns back with us from GG I and II.  We had, of course, and Alex has been studying some of the preserved specimens er brought to him in December.  Just yesterday I found an image of Dr. Tomio Iwamoto carefully processing these some of these same prawn specimens in 2006 on São Tomé (during GG II). This will give you an idea of the size of the critters Alex is studying (although there are two species on the islands – I am not sure which one this is!)

Tomio Iwamoto on Sao Tome.   RCD phot. GG II

The marine biologists of GG III (B) are busily sorting through their material, and I thought an early update was in order.   In the last blog I mentioned that the Dr. Williams had done very well with his octocorals (also known as gorgonians or sea fans), and so had Dr. Van Syoc and Dana Carrison with their barnacles. Dana is Bob Van Syoc’s graduate student at San Francisco State University.

Dana Carrison during a more northerly field trip. NOAA photo  

Bob Van Syoc found an undescribed barnacle species on São Tomé during GG II, and it appears that Dana has now confirmed this for Príncipe as well.  And there may well be other new barnacle species; it is just too soon to tell.  Dana is studying the relationship between these barnacles and Dr. Williams’ sea fans.  This is an obligate relationship – some species of sea fans are always found in association with certain species of barnacles.

 The barnacle Conopea calceola on a gorgonian.  D. Carrison phot. GG III

Note that the barnacle settles on the gorgonian, and the gorgonian’s tissue (red, in this case) grows up around it.  Along with describing new species and adding to our island biodiversity list, Dana is testing the hypothesis that the different species of barnacles have a preference for certain species of gorgonian upon which to settle. Dana got about 30 different Príncipe barnacles but has not yet begun identifying them or comparing them to the GG II barnacles collected in São Tomé.  Also included in her collections are at least three different gorgonians and their associated barnacles that were not collected previously by the Academy expeditions.

  Undescribed species of Conopea on a different species of gorgonian.  D. Carrison phot. GG III

New barnacle species or the relationships of freshwater prawns may not sound exciting to you.  In our biodiversity race, we are studying everything we can, as biodiversity is the sum of all living species in a given area; thus, everything is important as a measure of the uniqueness and past history of these ancient islands.  Think of our mushroom work: before we started, there were only four species known from São Tomé and none from Príncipe; now the people of the islands know that there are at least 220 species, many of them undescribed and unexpected.  The same is true for the ant lions I have documented earlier, and I fully expect similar results when analysis of our collections of diatoms and spiders are completed.  The story of biodiversity can never be told by the study of furred and feathers critters alone. 

Here’s the parting shot:  

Incipient Dr. Uyeda with collecting party, Nova Cuba, Principe. Weckerphoto GG III 

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 F. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke and Mr. and Mrs. Michael Murkami for helping make these expeditions possible.   

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Category: Biodiversity, Sao Tome, Uncategorized, coral, fish, invertebrates, nudibrachs, principe | Date: Feb 10 2009 | By: islandbiodiversityrace

 This is a brief update on the return of our people last weekend from Gulf of Guinea III (B). They were the marine component of the 2008-2009 expeditions (see Send in the Marines).  The focus of four of the group was the waters of Príncipe, the much older of the two islands.  The two fish people, Dr. John McCosker and David Catania went a week earlier to dive in São Tomé; neither had been to the islands before, and much of our earlier fish work was freshwater in nature. After the second group of four arrived, the whole expedition flew to Príncipe courtesy of SCD, one of our main sponsors (see “Partners,” below).   

As I posted earlier, our first nudibranch (sea slugs) specialist, Dr. Marta Pola-Perez, was on the GG III (B) expedition.  Below are photos of a few of the critters she found.

A possible new species of Phidiana, Principe. Pola-Perez phot. GG III

Flabelina arveloi, Principe.  Pola-Perez phot. GG III

Hypselodoris bilineata, Principe. Pola-Perez phot. GG III

As I wrote before, Dr. Bob Van Syoc, his graduate student, Dana Carrison and Dr. Gary Williams are looking at corals and barnacles and the association between the two life forms.  Dana’s dissertation topic concerns the relationship between what we think is a new species of barnacle and one of Gary’s octocorals (sea fans). 

A Sao Tome sea fan (Eunicella). G. Williams phot. GG III

This group did quite well on Príncipe; Bob and Dana collected a barnacle species previously known only from the Azores and Cape Verde Islands, Megabalanus azoricus, thus adding to the island diversity list.  Gary thinks he has now collected more species of octocorals in São Tomé and Príncipe than are found on the Galapagos Islands. 

Grad student, Dana Carrison, with sea fan on Principe. B. Van Syoc phot. GG III

 Dana, Gary Williams and John McCosker, Principe. B. Van Syoc phot. GG III

Of particular interest is that Bob found a species of shore barnacle at Bom Bom on Príncipe otherwise known only from South Africa. He thinks it was probably brought in by barge carrying building supplies.  So far it seems to be confined to the vicinity of the Bom Bom pier. 

Bom Bom pier at night, Principe. Weckerphoto GGIII

John and Dave also well.  Although they said the diving was “spotty” they did manage to sample a bunch of neat stuff, including at least one definite new species. 

A new species of Serranus from both islands.  D. Catania phot. GG III 

Ichthyologists frequently find new species just by exploring fish markets.  Below is a pot of jacks for sale which John and Dave cannot identify to species.  They will need to compare the DNA of these fishmarket critters with other known species in the genus.

Unidentified species of Caranx in the fishmarket.  J. McCosker phot. GG III

As I have written before, another way for ichthyologists to sample the marine fauna is to get permission to buy odd specimens directly from beach seiners.

 Sao Tome beach seine. J. McCosker phot. GG III] 

This group was fishing in the bay near Omali Lodge (Marlin Beach Hotel), and like Dr. Iwamoto did during GG I,  John and Dave dealt directly with the seiners for unique specimens.  Detirmining the identity of all of this material takes a great deal of time, but for now it looks as though the Marines of GG III (B) did quite well. 

I received some great news while the group was gone. Recall that I mentioned the marine group was going to collect some freshwater prawns for DNA work in a project by high school student Alex Kim in Virginia.  Well, the group got the prawns and by now they are back east being investigated by Alex and his mentor from George Mason University, Prof. Patrick Gillevet.  But the great news is that Alex is one of 40 finalists in the INTEL SCIENCE TALENT SEARCH; his project and scholarship are obviously gaining recognition, and we at the Academy are proud to be able to help out.

Alex has his own website: http://amphidrome.wordpress.com/  

Here’s the parting shot:  

Growing up on Principe. R. Wenk photo. GG III 

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 F. 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, biogeography, gigantism, invertebrates, lizards, principe | Date: Jan 26 2009 | By: islandbiodiversityrace

Our race to discover and describe the unique fauna and flora of São Tomé and Príncipe continues, and the six members of Gulf of Guinea Expedition III (B) are diving in the ancient waters of Príncipe as I write; they return to the Academy next week.  As I wrote earlier, Marta is sampling the sea slug fauna (nudibranchs), Gary, Bob and Dana are looking at coral and barnacles, having found a new species of the latter in waters off São Tomé during GG II, and John and David are looking at small marine fish, with emphasis on eels.  The group has an added goal, and that is to bring back some freshwater prawns (Macrobrachium) that abound in the São Tomé rivers. These specimens are for a young high school student named Alex Kim.

 A freshwater Macrobrachium prawn from Guinea (www.)

Alex is a senior at Thomas Jefferson High School of Science and Technology in Virginia.  He is doing an ambitious biogeography project on these prawns, relatives of which are found on both sides of the Atlantic.  Alex contacted me through this blog—you can read his comments at the end the November posting.  During a brief visit to DC over the holidays, I brought some preserved specimens we collected in GG I and GG II which I handed over to one of his advisors, Dr. Patrick Gillevet of George Mason University, and now the GG III (B) group plans to bring him some fresh material for DNA studies.  This is really fun academic stuff, and we are delighted to have the involvement of a young colleague.

 A Macrobrachium prawn from Cameroon. (www) 

Except for documenting our exciting hunt for Príncipe Jita, (see first May posting), I have not written that much about the endemic reptiles of these islands; in fact, there are quite a few of them, some rather spectacular.  While reptiles, especially geckos and skinks, are much better dispersers over saltwater than amphibians, snakes are not particularly good at it; moreover, like the amphibian caecilian, cobra bobo, a number of these endemics are legless species.  There are also some island species that may be endemic, but we are not sure…. we just haven’t studied them closely enough yet. In this posting I will show you the unique lizard species.  One readily identifiable endemic species is Greeff’s gecko, or the Giant gecko, Hemidactylus greeffii.  

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Greeff’s Gecko, Hemidactylus greeffii . A Sao Tome specimen. RCD phot. GG I   

Greeff’s gecko is an island giant; it is evidently much larger than other African member of the genus (and there are over 55 African taxa of Hemidactylus with likely many more to be discovered). Our longest specimen is over 200 mm in total length (including original tail); but longer specimens are known.  This gecko is not only very large it also differs from all of its African relatives in lacking a claw on the first (inner) finger and first toe. Somehow, this feature has been lost during the thousands, perhaps millions of years of isolation on the Gulf of Guinea Islands. Greeff’s gecko also has greenish eyes, which also distinguishes it from other nocturnal geckos on the island which, so far as we know, are not endemics.

 H. greeffii.  Note absence of claw on first thumb. ST specimen. RCD phot. GGI

H. greeffii with  greenish eyes.  ST specimen. D. Lin phot. GG II.

Greeff’s gecko occurs on both São Tomé and Príncipe; at least we think it does. Here’s what I mean: specimens from both islands look very much the same but a couple of years ago, a group of researchers from the University of Madeira and Portugal looked at the DNA of specimens from both islands and found that data from mitochondrial DNA suggested the two populations were very different, and that they may well be two distinct species in spite of their apparent anatomical similarity. These results were not confirmed by study of nuclear DNA however, so scientifically the “jury” is still out, and we call both island forms, Greeff’s gecko. This critter is quite common in rock walls, culverts, rock crevices on both islands and is strictly nocturnal. 

Principe specimen of Greeff’s gecko. D. Lin phot. GG II.  

A similar situation exists with a small terrestrial skink called Panaspis africana, or Gulf Leaf-litter skink. A daytime forager, this small uniform-brown skink is very common in the lowlands; it can be easily heard and seen scuttling through dried cacao leaves and it is almost always found on the ground on both islands; one of our largest gravid (with eggs) female specimens from São Tomé is about 100 mm in total length, but most of our examples are smaller.  

Gulf Leaf-litter skink. Panaspis africana; D. Lin phot. GG II. 

The same group of researchers from the University of Madeira studied the DNA of leaf litter skinks of both islands, and also Annobón, the last island in the chain and part of Equatorial Guinea.  They used, in part, tissues and specimens collected by us during GG I in 2001.  In this case they found clear evidence for three separate species, one on each island (the one on Annobón is already called P. annobonensis); this was supported by both mitochondrial and nuclear DNA sequence.  However, in one of those tragic, fortunately rare, occurrences in science, the specimens from which the tissue samples were taken were either lost in transit or misplaced.  Without voucher samples the results cannot be duplicated or tested nor can we demonstrate the results.  So for now, although there was evidence that Panaspis is two different species on São Tomé and Príncipe we cannot confidently describe the populations of the different islands nor give them scientific names.  Until the study can be redone with new material, the Gulf leaf-litter skinks remain known as simply Panaspis africana. 

Author working on Principe.  Weckerphoto. GGIII  

The way we collect these specimens is not sophisticated – we use our hands. We turn over logs, rocks and branches on the ground or sift through leaf litter with rakes; we climb trees and cliffs; we go out at night with flashlights and headlamps. After capture, the specimens are put in separate plastic bags for later processing.  

Dr. Iwamoto in Sao Tome H. greeffii habitat on Sao Tome. RCD phot. GG I 

Jens Vindum searching leaf litter on Sao Tome. D. Lin phot. GG II 

Principe day gecko in plasic bag. RDC phot. GG III.

Every specimen we collect gets a unique field number, which is the same used for photographs of it, recordings or tissues samples taken. 

My grad student, Ricka Stoelting,  processing specimens on Principe. RCD phot. GG I 

Certainly one of the oddest endemic lizards is the legless skink, unique to Príncipe Island, Feylinia polylepis.  There are about six species known in this genus, the remaining five found broadly distributed on the African mainland.   

Principe legless skink, Feylinia polylepis. brown  phase. D. Lin phot. GG I. 

 They appear in two different color morphs, a brown one and a pale gray one, regardless of size or sex.  The locals call them, Ozhgah (or at least the name  sounds like that). 

Principe legless skin - grey phase.  D. Lin  phot. GG II 

Feylinia polylepis head shot. D. Lin phot. GG II 

They can be found under almost anything on the ground provided the earth is slightly moist. Once exposed, they are very quick and can rapidly disappear into holes in the ground. They are conspicuously common in the Príncipe lowlands, and in this regard are reminiscent of the caecilians of São Tomé Island; the high density of their numbers in suitable habitats suggests predation may be low in these areas. 

Not all geckos are nocturnal.  In the Old World there are two large groups that are secondarily diurnal, although they, like all geckos, lack eyelids.  The genus Phelsuma is a group of numerous species of velvety green geckos found on Madagascar and the Indian Ocean islands; the other group, Lygodactylus are also present in Madagascar but also distributed throughout the Afrotropical region as well.  They are not brightly colored, and taxonomically rather poorly known.  The group as a whole is being studied by Dr. David Vieites (and his students) of Madrid and Dr. Adam Leache, of the University of Washington.  I have been involved as well but largely in studying the relationships of day geckos of the Gulf of Guinea Islands.  

 Lygodactylus thomensis. Sao Tome.  D. Lin  phot. GGI 

The Gulf of Guinea Day geckos are sun-lovers and strictly climbers, being fairly common on tree trunks and scuttling up walls even in São Tomé town and Santo Antonio, Príncipe.  They are very small, at about 70-80 mm total length.  The day geckos of the Gulf of Guinea islands (excluding the continental island of Bioko) have long been recognized as a distinct, endemic species, Lygodactylus thomensis, first discovered on São Tomé Island.  The day geckos on Príncipe and Annobón have been described as subspecies (or races, if you will) of the São Tomé species..  As you can see from the illustration below, one of the characteristics used to define species of day geckos is the throat pattern. 

 Day geckos of the Gulf of Guinea Islands.  RCD prep.

The throat patterns of the lizards on each of the three islands are quite consistently distinct from one another, and work by us and the University of Madeira suggest that they have been isolated from each other for a long, long time, and that each is a full species unique to its island. Work is continuing on these lizards.

 L. delicatus of Príncipe Island. RCD phot. GG III

 There are other conspicuous lizards on both islands but these are not considered endemics; i.e., they occur elsewhere and are probably just good over-water dispersers. The large speckled-lipped skink, Mabuya maculilabris, is common and widespread in the lowlands of both São Tomé and Príncipe. It is a good climber and is seen in a variety of habitats especially along the coast lines.  This species also broadly distributed on the African mainland.

 Speckle-lipped skink (Mabuya maculilabris) of the Gulf of Guinea. Sao Tome. D. Lin phot. GG II] 

M. maculilabris detail. D. Lin phot. GGII 

There are also non-endemic, nocturnal geckos on both islands. Most appear to be the widespread house gecko, Hemidactylus mabouia, also occuring nearly throughout Africa. 

House gecko, Hemidactylus mabouia.  D. Lin. phot.  GG II\] 

Note that the eyes are not greenish and that this species does not lack claws on the inner toe and finger.  There is some confusion as to how many non-endemic species are present and what to call them. 

H. mabouia foot from beneath. note claws. Weckerphoto GG III.

Snakes are coming next. 

Here’s the parting shot:  

The thrill of discovery! Bom Bom Island, Principe.  Weckerphoto. GG III  

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, 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 private individuals, George F. Breed, Gerry F. Ohrstrom, Timothy M. Muller, Mrs. W. H. V. Brooke and Mr. and Mrs. Michael Murkami for helping make these expeditions possible.  

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Category: Biodiversity, Gulf of Guinea, Island endemics, Sao Tome, invertebrates, principe | Date: Jun 30 2008 | By: islandbiodiversityrace

 Yes, the title is a play on words, and given the great threat posed to the unexplored natural environments of these two little unique islands by future oil revenues, I suppose a more appropriate title would be “Matters of Urgency,” but I couldn’t help myself.  In this posting I want to talk about the work of Dr. Richard Mooi, who was with us on GG II.  

Rich stalks an unsuspecting sea urchin on São Tomé. D. Lin phot. GG II. 

Dr.Rich Mooi is a Curator in our Department of Invertebrate Zoology, but more importantly to us (and to the blog title!), he is one of the world’s authorities on echinoderms, a large phylum that includes sea urchins, seas stars and what we Americans call “sand dollars,” the flat, disk-like tests (endoskeletons) of which we find commonly on our beaches.  One of the most fascinating, yet poorest known sand dollars in the world is Rotula deciesdigitata, known only from the Gulf of Guinea.  This species is probably not really rare but the places it occurs are remote and not frequently visited by scientists.  Hence, they are super-scarce in the world’s natural history collections; even more so in North America.

Technical photo.  Rotula deciesdigitata. 

The unit of currency in the Republic of São Tomé and Prìncipe is the Dobra; there are about 15,000 of ‘em to the US dollar.  Here is a photo of a bunch of dobras drying on my bed at Bom Bom Island on Principe.  Why? Well, the wonderful folks at Bombom Island and SCD allowed us to attempt to survey by boat the otherwise inaccessible southwest shore of Prìncipe; at a critical point, too many of us climbed into a small red dinghy and flipped in the surf.  Along with the dobras went a lot of equipment including cameras, my cell phone, ipod, etc.—more on this in another posting.

Drying dobras  RCD GGIII

The offending boat, post-flipping.  Weckerphoto GG III 

Anyway, once we finally found specimens of Rich’s Rotula, it was only natural that they become “sand dobras,” and the only beach we have found them on the west side of Sao Tome became Sand Dobra Beach– its real name is Praia Morrão.

Rotula deciesdigitata on Sand Dobra Beach.  D. Lin phot. GG II 

During GG II, Rich and I swam out beyond the surf line to try to secure a live specimen for DNA analysis (remember, the test you find on the beach is not the living animal, but rather its endoskeleton).  The undertow was so powerful that we both nearly drowned, but we did find one specimen that retained a greenish color, suggesting that there might be some remaining tissue to analyze; the jury is still out on this. The sand dobras present a rather interesting mystery, in that they appear to be wholly unrelated to those of the New World, while such might not be the case with other echinoderms. In his own words, Rich says “this strange pattern is further underscored by the fact that as I looked at all the other echinoderms around Sao Tome, the faunas were nearly perfectly Caribbean in nature.  There were times that I felt as though I was snorkeling around in Florida or Belize — at least as far as the sea urchins were concerned.  The rotulids were a glaring exception to that.”

Rich working.  D. Lin phot. GG II.   

Interestingly, there are many species with holes and notches in them throughout the Caribbean.  These are almost all members of a sand dollar family known as the Mellitidae. However, there are absolutely no mellitids on the west coast of Africa.  In fact, there are no “true” sand dollars at all.  The truth is that the Gulf of Guinea sand dobras are not even closely related to the Caribbean sand dollars, but belong not only to a different family (Rotulidae), but to a completely different major clade (suborder). This is perplexing. 

Rotula deciesdigitata on Sand Dobra Beach. Weckerphoto  GG III 

Dr. Rich Mooi is still working on the many fascinating echinoderms he collected on the beaches and tidepools of  São Tomé and Prìncipe in 2006, and I will report his discoveries as they appear.     

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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