Tag Archives: flatworms

The hammerhead flatworms: once a mess, now even messier

by Piter Kehoma Boll

Few people know that land planarians exist, but when they do, they most likely know the hammerhead flatworms, which comprise the subfamily Bipaliinae.

The hammerhead flatworms, or simply hammerhead worms, have this name because their head has lateral expansions that make them resemble a hammer, a shovel or a pickaxe. Take a look:

Bipalium_vagum

The “wandering hammerhead worm”, Bipalium vagum. Notice the peculiar head. Photo by flickr user budak.*

The Chinese knew the hammerhead worms at least since the 10th century, which is understandable, since they are distributed from Japan to Madagascar, including all southern and southeast Asia, as well as Indonesia, the Philippines and other archipelagos. The western world, however, first heard of them in 1857, when William Stimpson described the first species and put them in a genus called Bipalium, from Latin bi- (two) + pala (shovel), due to the head shape. One of them was the species Bipalium fuscatum, a Japanese species that is currently considered the type species of the genus.

800px-bipalium_fuscatum_by_head

Anterior region of Bipalium fuscatum, the “brownish hammerhead worm”. Photo by Wikimedia user 根川大橋.**

Two years later, in 1859, Ludwig K. Schmarda described one more species, this one from Sri Lanka, and, unaware of Stimpson’s paper, called the species Sphyrocephalus dendrophilus, erecting the new genus for it from Greek sphȳra (hammer) + kephalē (head).

Sphyrocephalus_dendrophilus

Drawings by Schmarda of Sphyrocephalus dendrophilus.

In the next year, 1860, Edward P. Wright did something similar and described some hammerhead worms from India and China, creating a new genus, Dunlopea, for them. The name was a homage to his friend A. Dunlop (whoever he was).

Dunlopea_grayia

Wright’s Drawing of Dunlopea grayia (now Diversibipalium grayi) from China.

Eventually those errors were perceived and all species were put in the genus Bipalium, along with several others described in the following years. All hammerhead worms were part of the genus Bipalium until 1896, when Ludwig von Graff decided to improve the classification and divided them into three genera:

1. Bipalium: With a head having long “ears”, a well developed head.
2. Placocephalus (“plate head”): With a more semicircular head.
3. Perocephalus (“mutilated head”): With a shorter, rudimentary head, almost as if it had been cut off.

Bipaliids

Compare the heads of typical species of Bipalium (left), Placocephalus (center) and Perocephalus (right), according to Graff.

This system, however, was soon abandoned and everything went back to be simply Bipalium and continued that way for almost a century, changing again only in 1998, when Kawakatsu and his friends started to mess with the penises of the hammerhead worms.

First, in 1998, they erected the genus Novibipalium (“new Bipalium“) for species with a reduced or absent penis papilla, and retained in Bipalium those with a “well”-developed penis papilla. It is worth noticing though that this well-developed papilla is not much bigger than a reduced papilla in Novibipalium. In both genera the actual, functional penis is formed by a set of folds in the male atrium and not by the penis papilla itself as in other land planarians that have a penis papilla.

Later, in 2001, Ogren & Sluys separated some more species of Bipalium in a new genus called Humbertium (after Aloïs Humbert, who described most species of this new genus). They were separated from Bipalium because the ovovitelloducts (the ducts that conduct the eggs and vitellocites) enter the female atrium from ahead, and not from behind as in the typical Bipalium. This separation is, in my opinion, more reasonable than the previous one.

Now we had three genera of hammerhead worms based on their internal anatomy, but several species were described without any knowledge of their sexual organs. Thus, in 2002, Kawakatsu and his friends created one more genus, Diversibipalium (the “diverse Bipalium“) to include all species whose anatomy of the sexual organs was unknown. In other words, it is a “wastebasket” genus to place them until they are better studied.

Are these three genera, Bipalium, Novibipalium and Humbertium, as now defined, natural? We still don’t know, but I bet they are not. A good way to check it would be by using molecular phylogeny, but we don’t have people working with these animals in their natural habitats, so we do not have available material for that. Another thing that can give us a hint is to look at their geographical distribution. We can assume that genetically similar species, especially of organisms with such a low dispersal ability as land planarians, all occur in the same geographical region, right? So where do we find species of each genus? Let’s see:

Bipalium: Indonesia, Japan, China, Korea, India.

Novibipalium: Japan.

Humbertium: Madagascar, Sri Lanka, Southern India, Indonesia.

Weird, right? They are completely mixed and covering a huge area of the planet, especially when we consider Humbertium. We can see a tendency, but nothing very clear.

Fortunately, some molecular analyses were published (see Mazza et al. (2016) in the references). One, which included the species Bipalium kewense, B. nobile, B. adventitium, Novibipalium venosum and Diversibipalium multilineatum placed Diversibipalium multilineatum very close to Bipalium nobile, and they are in fact very similar, so I guess that we can transfer it from Diversibipalium to Bipalium, right? Similary, Novibipalium venosum appears mixed with the species of Bipalium. I guess this is kind of messing things up one more time.

681px-bipalia_invasive

Head of some species of Bipalium, including the ones used in the study cited above. Unfortunately, I couldn’t find a photo or drawing of Novibipalium venosum. Image by myself, Piter Kehoma Boll.**

Interestingly, among the analyzed species, the most divergent was Bipalium adventitium, whose head is “blunter” than that of the other ones. Could the head be the answer, afterall? Let’s hope that someone with the necessary resources is willing to solve this mess soon.

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See also:

Once found and then forgotten: the not-so-bright side of taxonomy.

The lack of taxonomists and its consequences on ecology.

They only care if you are cute. How charisma harms biodiversity.

The faboulous taxonomic adventure of the genus Geoplana.

Darwin’s Planaria elegans: hidden, extinct or misidentified?

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References:

Graff, L. v. (1896) Über das System und die geographische Verbreitung der Landplanarien. Verhandlungen der Deutschen Zoologischen Gesellschaft6: 61–75.

Graff, L. v. (1899) Monographie der Turbellarien. II. Tricladida Terricola (Landplanarien). Engelmann, Leipzig.

Kawakatsu, M.; Ogren, R. E.; Froehlich, E. M. (1998) The taxonomic revision of several homonyms in the genus Bipalium, family Bipaliidae (Turbellaria, Seriata, Tricladida, Terricola). The Bulletin of Fuji Women’s College Series 236: 83–93.

Kawakatsu, M.; Ogren, R. E.; Froehlich, E. M., Sasaki, G.-Y. (2002) Additions and corrections of the previous land planarians indices of the world (Turbellaria, Seriata, Tricladida, Terricola). The bulletin of Fuji Women’s University. Ser. II40: 162–177.

Mazza, G.; Menchetti, M.; Sluys, R.; Solà, E.; Riutort, M.; Tricarico, E.; Justine, J.-L.; Cavigioli, L.; Mori, E. (2016) First report of the land planarian Diversibipalium multilineatum (Makino & Shirasawa, 1983) (Platyhelminthes, Tricladida, Continenticola) in Europe. Zootaxa4067(5): 577–580.

Ogren, R. E.; Sluys, R. (2001) The genus Humbertium gen. nov., a new taxon of the land planarian family Bipaliidae (Tricladida, Terricola). Belgian Journal of Zoology131: 201–204.

Schmarda, L. K. (1859) Neue Wirbellose Thiere beobachtet und gesammelt auf einer Reise um die Erde 1853 bis 1857 1. Turbellarien, Rotatorien und Anneliden. Erste Hälfte. Wilhelm Engelmann, Leipzig.

Stimpson, W. (1857) Prodromus descriptionis animalium evertebratorum quæ in Expeditione ad Oceanum, Pacificum Septentrionalem a Republica Federata missa, Johanne Rodgers Duce, observavit er descripsit. Pars I. Turbellaria Dendrocœla. Proceedings of the Academy of Natural Sciences of Philadelphia9: 19–31.

Wright, E. P. (1860) Notes on Dunlopea. Annals and Magazine of Natural History, 3rd ser.6: 54–56.

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Land snails on islands: fascinating diversity, worrying vulnerability

by Piter Kehoma Boll

The class Gastropoda, which includes snails and slugs, is only beaten by the insects in number of species worldwide, having currently about 80 thousand described species. Among those, about 24 thousand live on land, where they are a very successful group, especially on oceanic islands.

The Hawaiian Islands alone, for example, have more than 750 snail species and there are more than 100 endemic species in the small island of Rapa in the South Pacific. This diversity is much higher than that in any continental place, but the reason for that is not completely understood.

Mandarina

A land snail of the genus Mandarina, endemic to the Ogasawara Islands, Japan. Photo by flickr user kmkmks (Kumiko).*

One of the most likely explanations for this huge diversity on islands is related to the lack of predators. The most common predators of snails include birds, mammals, snakes, beetles, flatworms and other snails. Most of those are not present in small and isolated islands, which allows an increase in land snail populations in such places. Without too much dangers to worry about, the community of land snails n islands can explore a greater range of niches, eventually leading to speciation.

Unfortunately, as always, the lack of danger leads to recklessness. Without predators to worry about, insular land snails tend to lay fewer eggs than their mainland relatives. If there is no danger of having most of your children eaten, why would you have that many? It is better to lay larger eggs, putting more resources on fewer babies, and so assure that they will be strong enough to fight against other snail species. Afterall, the large number of species in such a small place as an island likely leads to an increased amount of competition between species.

But why is this recklessness? Well, because you never known when a predator will arrive. And they already arrived… due to our fault.

The diversity of insular land nails was certainly affected by habitat loss promoted by humans, but also by predators that we carried with us to the islands, whether intentionally or not. These predators include rats, the predatory snail Euglandina rosea and the land flatworm Platydemus manokwari, the latter being most likely the worst of all.

800px-platydemus_manokwari

The flatworm Platydemus manokwari in the Ogasawara Islands. Photo by Shinji Sugiura.

This flatworm arrived at the Chichijima Island, part of the Ogasawara Islands in the Pacific Ocean, in the early 1990s and in about two decades it led most land snail species on the island to extinction and many more are about to face the same fate on this island and on others. Not being prepared for predators, these poor snails cannot reproduce fast enough to replace all individuals eaten by the flatworm.

We have to act quickly if we want to save those that are still left.

See also: The New Guinea flatworm visits France – a menace.

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ResearchBlogging.orgReferences and further reading:

Chiba, S., & Cowie, R. (2016). Evolution and Extinction of Land Snails on Oceanic Islands. Annual Review of Ecology, Evolution, and Systematics, 47 (1), 123-141 DOI: 10.1146/annurev-ecolsys-112414-054331

Sugiura, S., Okochi, I., & Tamada, H. (2006). High Predation Pressure by an Introduced Flatworm on Land Snails on the Oceanic Ogasawara Islands. Biotropica, 38 (5), 700-703 DOI: 10.1111/j.1744-7429.2006.00196.x

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Friday Fellow: Persian Carpet Flatworm

ResearchBlogging.orgby Piter Kehoma Boll

A flatworm again, at last! Not a land planarian, but a flatworm nonetheless.

If there is a group of flatworms that may put land planarians in second plan regarding beauty, those are the polyclads. Living in the sea, especially in coral reefs, polyclads are colorful and curly and may be mistaken by sea slugs.

The species I’m introducing here today is Pseudobiceros bedfordi, commonly known as the Persian carpet flatworm or Bedford’s flatworm. It is about 8 cm long and lives in coral reefs along Australia, Indonesia, Philippines and adjacent areas. See how beautiful it is:

A flatworm (Pseudobiceros bedfordi). Raging Horn, Osprey Reef, Coral Sea

The Persian carpet flatworm with its beautiful colors. Photo by Richard Ling.*

The colorful pattern of this and many other polyclad species is likely a warning about their toxicity, although there are few studies regarding toxicity in these animals. Being active predators, polyclads may use their toxins as a way to subdue prey as well.

But the most interesting thing regarding the Persian carpet flatworm is its sexual behavior. As with most flatworms, they are hermaphrodites, so when two individuals meet and decide to have sex, they have to choose whether they want to play the male or the female role (or both). Unfortunately, most individuals prefer to be males, so those encounters usually end up in a violent fight in which both animals attack the partner with a double penis, a behavior known as penis fencing.

mating_pseudobiceros_bedfordi

Two Persian carpet flatworms about to engage in penis fencing. Photo from Whitfield (2004), courtesy of Nico Michiels.**

At the end, the winner spurts its sperm onto the partner and leaves. The horrible part is yet to come, though. The sperm appears to be able to burn like acid through the receiver’s skin tissue in order to reach the inner tissues and thus swim towards the eggs. In some extreme cases the sperm load may be high enough to tore the receiver into pieces! If that’s not a good definition of wild sex, I don’t know what is.

See also: Gender Conflict: Who’s the man in the relationship?

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References:

Whitfield, J. (2004). Everything You Always Wanted to Know about Sexes PLoS Biology, 2 (6) DOI: 10.1371/journal.pbio.0020183

Wikipedia. Pseudoceros bedfordi. Available at: <https://en.wikipedia.org/wiki/Pseudobiceros_bedfordi&gt;. Access on November 24, 2016.

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Obama invades Europe: “Yes, we can!”

ResearchBlogging.orgby Piter Kehoma Boll

This information was known by me and some other people for quite a while, but only recently has caught attention of the general public. Obama is the newest threat in Europe.

No, I’m not talking about the president of the United States. I’m talking about a land flatworm whose name is  Obama nungara.

obama_marmorata_7

This is the magnificent Obama nungara. This specimen is from Brazil and looks particulary yellowish due to the strong light of the camera flash. Photo by Piter Kehoma Boll.*

It has been a while since a new invasive land flatworm started to appear in gardens of Europe, especially in Spain and France and eventually elsewhere, such as in the United Kingdom. It was quickly identified as being a Neotropical land planarian and posteriorly as belonging to the genus Obama, whose name has nothing to do with Barack Obama, but is rather a combination of the Tupi words oba (leaf) and ma (animal) as a reference to the worm’s shape.

obama_nungara

When you find Obama nungara in your garden, it will look much darker, like this one found in the UK. Photo by buglife.org.uk

At first it was thought that the planarian belonged to the species Obama marmorata, a species that is native from southern Brazil, but molecular and morphological analyses revealed it to be a new species. Actually, much of what was called Obama marmorata in Brazil was this new species. Thus, it was named nungara, which means “similar” in Tupi, due to its similarity with Obama marmorata.

obama_marmorata

This is Obama marmorata, the species that O. nungara was originally mistaken for. Photo by Fernando Carbayo.**

Measuring about 5 cm in length, sometimes a little more or a little less, O. nungara is currently known to feed on earthworms, snails, slugs and even other land planarians. Its impact on the European fauna is, however, still unknown, but the British charitable organization Buglife decided to spread an alert and many news websites seem to have loved the flatworm’s name and suddenly a flatworm is becoming famous.

Who said flatworms cannot be under the spotlight? Yes, they can!

See also: The Ladislau’s flatworm, a cousin of Obama nungara.

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References:

Álvarez-Presas, M., Mateos, E., Tudó, À., Jones, H., & Riutort, M. (2014). Diversity of introduced terrestrial flatworms in the Iberian Peninsula: a cautionary tale PeerJ, 2 DOI: 10.7717/peerj.430

Boll, P., & Leal-Zanchet, A. (2016). Preference for different prey allows the coexistence of several land planarians in areas of the Atlantic Forest Zoology, 119 (3), 162-168 DOI: 10.1016/j.zool.2016.04.002

Carbayo, F., Álvarez-Presas, M., Jones, H., & Riutort, M. (2016). The true identity of Obama (Platyhelminthes: Geoplanidae) flatworm spreading across Europe Zoological Journal of the Linnean Society, 177 (1), 5-28 DOI: 10.1111/zoj.12358

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New Species: September 21 to 30

by Piter Kehoma Boll

Here is a list of species described from September 21 to September 30. It certainly does not include all described species. Most information comes from the journals Mycokeys, Phytokeys, Zookeys, Phytotaxa, Zootaxa, International Journal of Systematic and Evolutionary Microbiology, and Systematic and Applied Microbiology, as well as journals restricted to certain taxa.

mysidella_hoshinoi

Mysidella hoshinoi is a new species of possum shrimp described in the past 10 days.

SARs

Plants

Fungi

Sponges

Flatworms

Annelids

Mollusks

Nematodes

Arachnids

Myriapods

Crustaceans

Hexapods

Ray-finned fishes

Lissamphibians

Reptiles

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The fabulous taxonomic adventure of the genus Geoplana

by Piter Kehoma Boll
ResearchBlogging.org

Freshwater planarians are relatively well-known as those cute arrow-shaped cockeyed animals. Land planarians are far away from having all the fame of their aquatic cousins and most people do not even know that they exist. Maybe in part it is because deeper studies of the natural world began in Europe, a continent were land planarians are almost non-existent. The first of those little animals to be known was described in 1774 by the Danish naturalist Otto Friedrich Müller. He named the small worm Fasciola terrestris, because he thought it was a terrestrial version of the parasitic worm. It was a small cyllindrical worm with a dark back and two small eyes at the anterior region.

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In 1788, the naturalist Johann Friedrich Gmelin transfered the species to the genus Planaria, described in 1776 by Müller. The worm was, therefore, now called Planaria terrestris. The genus, at this time, included everything that is currently known as planarian: worms with a ventrally located mouth, close to the middle part of the bod. The term most likely became popular by this time and so it continues until today as a general name for these animals.

planaria_terrestris

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Planarians with many eyes were transfered in 1831 by the naturalist Christian Gottfried Ehrenberg to a new genus, Polycelis. The term means “many dots” and refers to the dark dots that the eyes represent on the body.

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During Charles Darwin’s voyage around the world aboard the Beagle, he spent some time in the Brazilian Atlantic Forest and found several species of land planarians. He classified them in the genus Planaria, but highlighted that they formed a section within the genus because of their terrestrial habits, convex bodies and often colorful stripes. The first new species listed by him was called Planaria vaginuloides and was collected in the forests of Rio de Janeiro. The epithet vaginuloides was chosen because Darwin found them to be similar to slugs of the genus Vaginulus.

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One year later, in 1845, the naturalist Émil Blanchard found a species in Chile and named it Polycladus gayi. The name of the genus, Polycladus, refers to the highly branched gut of these animals, while the epithet gayi honors the naturalist Claudio Gay. But Blanchard made a terrible mistake: he mistook the anterior end for the posterior end and so thought that the genital opening was in front of the mouth!

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In 1850, the naturalist Karl Moriz Diesing transferred Darwin’s land planarians to the genus Polycelis because they have many eyes. Planaria vaginuloides was now Polycelis vaginuloides.

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In 18851, the zoologist Joseph Leidy found another land planarian species in Europe that was also small, cylindrical and with two eyes. He named it Rhynchodemus sylvaticus. The term Rhynchodemus means something like “bill-shaped body”. He also suggested the transference of Planaria terrestris to the new genus, so that it was now Rhynchodemus terrestris. Darwin and Blanchard’s species remained as Polycelis and Polycladus.

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Then in 1857 something funny happened. A new revision of land planarians was done by William Stimpson. He, for the first time, separated land planarians from freshwater ones and divided them in two families:

  1. Polycladidae: having a single genus, Polycladus, because it was still thought, at this time, that the genital opening was before the mouth.
  2. Geoplanidae: the rest of land planarians. Species in this family were divided into three genera:
  • Rhynchodemus: species with two eyes;
  • Bipalium: a genus for recently discovered species that have a hammer- or crescent-shaped head. The name comes from Latin bi-, two and pala, shovel.
  • Geoplana: species with many eyes. The name comes from geo, earth, and plana, flat, because of the flat body of those animals, as well as a direct reference to the genus Planaria, now restricted to aquatic species. The species Polycelis vaginuloides became Geoplana vaginuloides. So we arrive to the central genus of this story.
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By a huge coincidence, in this very same year of 1857, the naturalist Max Schultze, based on information from literature and new species collected in Brazil by the naturalist Fritz Müller, also decided to separate land planarians into another genus and also chose the name Geoplana! What are the chances? The papers of Stimpson and Schultze had only some weeks between them and everything seems to indicate that Schultze was unaware of Stimpson’s paper. The main difference between both papers is that Schultze ignored the discovery of the species classified as Bipalium. He also transfered all land planarians to Geoplana, so that Polycladus gayi, Rhynchodemus sylvaticus and Rhynchodemus terrestris were now Geoplana gayi, Geoplana sylvatica and Geoplana terrestris.

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Stimpson’s system, however, prevailed, and the four genera remained in use: Rhynchodemus, Bipalium, Geoplana and Polycladus. Among the species described by Schultze and Müller was Geoplana subterranea, an albine and eyeless species found underground and that feeds on earthworms. In 1861, Diesing decided to put this species into its own genus, Geobia. We had now 5 genera: Rhynchodemus, Bipalium, Geoplana, Geobia and Polycladus.

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In 1877, Henry Nottidge Moseley described a series of species from Australia, the Pacific and southeast Asia. A good amount of them were included in the genus Geoplana, but some of them were put in two new genera:

  1. Dolichoplana (“long flat”): very long and narrow species with two eyes as in Rhynchodemus;
  2. Caenoplana (“recent flat”): species considered by him to be intermediate between Geoplana and Dolichoplana because the body was longer and the eyes were restricted to the sides of the body.
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Ten years later, in 1887, J. J. Fletcher and A. G. Hamilton studied Australian land planarians and concluded that there was no need for the species named Caenoplana by MOseley to be in a separate genus and united them to Geoplana.

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During the following decade, the naturalist Arthur Dendy described several new species from Australia and New Zealand, classifying all in the genus Geoplana. The genus was growing, having tenths of species. In the last years of the 19th century, several new genera were created, many of them in the works of the zoologist Ludwig von Graff. These new genera were erected to species with very peculiar anatomical features, such as a differentiated head, for example. Anyway, the genus Geoplana kept growing. Any flat and many-eyed land planarian without a distinct feature was thrown into this genus. This system continued throughout most of the 20th century. Tenths of new species were described by the zoologist Libbie Hyman and by two zoologist couples: the Marcuses – Ernst Marcus and Eveline du Bois-Reymond Marcus – and the Froehlichs — Claudio Gilberto Froehlich and Eudóxia Maria Froehlich. These new species were mostly put in Geoplana. At that time the genus was widely distributed in South America and Australia.

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During this time, E. M. Froehlich determined that Geoplana vaginuloides should be the type species of the genus Geoplana. Perhaps you are now asking yourself “what is a type species?”. Well, in taxonomy, when a new genus is created, one of its species has to be considered the type species, the species that serves as a “model” to the genus. It is the type species that defines what the genus is. Once a species becomes the type species of the genus, it can never pass to another genus, except if the entire genus ceases to exist. Afterall, it is the species in which the existence of the genus is based. The fact is that in the 18th and 19th centuries there was no policy of type species, which was only later introduced in the rules to give names to organisms. Therefore Stimpson, when he created the genus Geoplana, did not define a type speciees. E. M. Froehlich chose Geoplana vaginuloides as the type-species because it was the first species listed by Stimpson and the proposal was accepted by the scientific community.

Let’s go back to the main subject. As it was said, the genus Geoplana was gathering more and more species throughout the 20th century, becoming huge. Then in 1990 the zoologists Robert Ogren and Masaharu Kawakatsu decided to clean the mess. By examining the inner anatomy of land planarians, they excluded from Geoplana all species from Australia and nearby areas because they have testes placed in the ventral region of the body, diferently from South American species, that have them in the dorsal region. However, letting all the South American pack inside Geoplana would still be a mess. So, they broke the genus into several smaller genera. The four main genera were defined based on two features of the copulatory apparatus: 1) the presence or absence of a penis papilla, i.e., a penis. Some planarians have a penis and some don’t. 2) The position of the oviducts, i.e., the canals that carry the eggs from the ovaries to a cavity named female atrium. The oviducts may enter the female atrium at the dorsal side or the ventral side. The classification of this two features allows four combinations:

  1. Species with a penis papilla and with oviducts entering dorsally. These species continued in the genus Geoplana, because this is the combination that occurs in Geoplana vaginuloides.
  2. Species with a penis papilla and with oviducts entering ventrally. These species passed to the genus Gigantea.
  3. Species without a penis papilla and with oviducts entering dorsally. These species were named Notogynaphallia.
  4. Species without a penis panilla and with oviducts entering ventrally. This is the opposite of what is found in Geoplana. These species were transfered to a genus named Pasipha.
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Things were starting to get more organized. Despite still having more than a hundred species, the genus Geoplana was a little more homogeneous now. But by the beginning of the 21th century, more detailed studies on the internal anatomy of planarians demonstrated that other parts of the body also had taxonomic importance. Furthermore, molecular studies were now available and the genus was challenged by the molecular phylogeny. The already expected result was confirmed. A study of molecular phylogeny by Fernando Carbayo and colleagues in 2013 revealed that the genus Geoplana, as defined by Ogren and Kawakatsu, was still a mess. Species were separated in several groups that needed to received their own genera. These new genera created from Geoplana were: Barreirana, Cratera, Matuxia, Obama and Paraba.

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At the end the type species, Geoplana vaginuloides, remained almost alone. The only other species that grouped with it was Geoplana chita. The genus Geoplana, once with hundreds of species throughout the whole world, now has only two species restriced to the Atlantic Forest between the Brazilian states of Rio de Janeiro and Paraná. And guess which of the new genera received most of the species one in Geoplana?

 

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Yes, we can!

Yes, we can!

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References:

Carbayo, F., Álvarez-Presas, M., Olivares, C., Marques, F., Froehlich, E., & Riutort, M. (2013). Molecular phylogeny of Geoplaninae (Platyhelminthes) challenges current classification: proposal of taxonomic actions Zoologica Scripta, 42 (5), 508-528 DOI: 10.1111/zsc.12019

Darwin, C. 1844. Brief description of several terrestrial planariae, and of some remarkable marine species, with an account of their habits. Annals and Magazine of Natural History, Annales de Sciences Naturelles, 14: 241-251.

Diesing. K. M. 1850. Systema helminthum. Academia Caesareae Scientiarium.

Fletcher, J. J.; Hamilton, A. G. 1887. Notes on Australian land-planarians, with descriptions of some new species. Part I. Proceedings of the Linnean Society of New South Wales, 2: 349-374.

Froehlich, E. M. 1955. Sôbre espécies brasileiras do gênero GeoplanaBoletim da Faculdade de Filosofia, Ciências e Letras da Universidade de São Paulo, Série Zoologia, 19: 289-339.

Gay, Claudio. 1849. Historia fisica y politica de Chile. Vol. 3.

Gmelin, O. F. 1788. Systema Naturae. Moseley, H. N. 1877. Notes on the structure of several forms of land planarians with a description of two new genera and several new species, and a list of all species at present known. Quarterly Journal of Microscopical Sciences, 17: 274-292.

Ogren, R.; Kawakatsu, M. 1990. Index to the species of the family Geoplanidae (Turbellaria, Tricladida, Terricola) Part I: Geoplaninae. Bulletin of Fuji Women’s College, 28: 79-166.

Schultze, M.; Müller, F. 1857. Beiträge zur Kenntnis der Landplanarien. Abhandlungen der Naturforschenden Gesellschaft zu Halle, 4: 61-74.

Stimpson, W. 1857. Prodromus descriptionis animalium evertebratorum quae in expeditione ad Oceanum, Pacificum Septentrionalem a Republica Federata missa Johanne Rodgers Duce, observavit et descripsit. Pars I. Turbellaria Dendrocoela. Proceedings of the Academy of Natural Sciences of Philadelphia, 19-31.

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Filed under Molecular Biology, Systematics, taxonomy, worms, Zoology

Friday Fellow: ‘Abundant Yellow-Striped Flatworm’

by Piter Kehoma Boll

ResearchBlogging.org Today our Friday Fellow is an almost unknown species from an almost unknown group: Luteostriata abundans (formerly Notogynaphallia abundans) is a land planarian (a flatworm) found in southern Brazil, mainly in urban areas. It’s common to find it around in gardens and parks, hidden under leaves, stones and logs.

Two planarians Luteostriata abundans, named by me as Pierre and Marie (don’t forget they are hermaphrodites, though). Photo by Piter Kehoma Boll.

Most land planarians are very poorly known, even though they are recognized as good bio-indicators of conservation. However, there is an article published about the feeding habits of L. abundans (Prasniski & Leal-Zanchet, 2009). Currently it’s only known that it feeds on woodlice, but since it’s a very common species in disturbed areas, its diet probably includes something else. (I’m studying the predatory behavior of this and other species, but haven’t found any other prey item for it yet…)

Here at IPP (Instituto de Pesquisa de Planárias, in English “Planarian Research Institute”), we are also doing research about the regeneration of L. abundans. Everybody knows how well freshwater planarians can regenerate when cut into several pieces. Land planarians don’t seem to be so skilled, but very little is known about them on this subject too!

Another interesting fact that we noticed about L. abundans is their ability to escape from almost every container you put them into. We need to seal the lid of their plastic containers with adhesive tape and yet they sometimes manage to find a way to leave.

There is so much yet to know about these flatworms. As predators, they are essential to balance the population size of their prey in conserved areas and for those species known to live well in urban places, knowledge of their feeding habits is important to evaluate their chance to become invasive.

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References:

Carbayo, F. 2010. A new genus for seven Brazilian land planarian species, split off from Notogynaphallia (Platyhelminthes, Tricladida) Belgian Journal of Zoology, 140 (Suppl.), 91-101

Prasniski, M. E. T. & Leal-Zanchet, A. M. 2009. Predatory behavior of the land flatworm Notogynaphallia abundans (Platyhelminthes: Tricladida) Zoologia, 26, 606-612 DOI: 10.1590/S1984-46702009005000011

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Filed under Behavior, Friday Fellow