A study of the molecular phylogenetic interrelationships of south Asian cyprinid genera Danio, Devario and Microrasbora has resulted in a reclassification of the group and the creation of a new genus: Microdevario.

The study, which has been published in a recent issue of the journal Zoologica Scripta, was carried out by Fang Fang and his colleges at the Swedish Museum of Natural History.

The researchers examined the molecular phylogeny of the Danioninae using fragments of the mitochondrial cytochrome b and nuclear rhodopsin genes from 68 species, including 43 danioinine species.

The analysis revealed the species Microrasbora rubescens and the genera Chela, Laubuca, Devario, and Inlecypris to form a natural group, the Devario clade, with the species Microrasbora gatesi, Microrasbora kubotai and Microrasbora nana being in sister group position to the rest.

Zebrafish

These findings, in combination with subsequent analysis of morphological characters, have made the authors propose four taxonomic changes:

· The species Inlecypris auropurpurea is reassigned as Devario auropurpureus.

· Microrasbora gatesi, Microrasbora kubotai and Microrasbora nana are reassigned to a new genus named Microdevario. Fish of this genus are distinguished from other danioinines by a combination of skull and jaw characters.

· Reassignment of the species Celestichthys margaritatus to the genus Danio in previous studies is confirmed.

· The membership of Chela is restricted to Chela cachius. All other species previously placed in this genus are reassigned to the genus Laubuca, except Chela maassi, which is in the genus Malayochela.

For more information about the study and the suggested taxonomic changes, see the paper Fang, F, M Norén, TY Liao, M Källersjö and SO Kullander (2009) Molecular phylogenetic interrelationships of the south Asian cyprinid genera Danio, Devario and Microrasbora (Teleostei, Cyprinidae, Danioninae). Zoologica Scripta 38, pp. 237–256.

According to the journal Surgery, a 50 cm (20 in) eel was removed from a man’s rectum at the Kwong Wah Hospital in Kowloon, Hong Kong.

The 50-year old man was admitted to the Accident and Emergency Department complaining about abdominal pain.

European Eel – Picture by Ron Offermans; GNU

Doctors diagnosed him with peritonitis, inflammation of the peritoneum*, and did an x-ray to find out the underlying cause. Interestingly enough, what they saw on the x-ray was an eel stuck inside the man’s rectum.

The eel was still alive and biting the patient’s splenic flexure, which is a sharp bend located between the transverse and the descending colon. Doctors also found a 3 cm perforation over the anterior wall of the rectum.

“On further questioning,” says the paper, “the patient admitted an eel was inserted into the rectum in an attempt to relieve constipation. This may be related to a bizarre healthcare belief, inadvertent sexual behaviour, or criminal assault. However, the true reason may never be known.”

The patient was released from hospital a week later. We have been unable to find any information about what happened to the eel.

* The peritoneum is a serous membrane that forms the lining of the abdominal cavity or the coelom.

Filtered cigarette butts should have new requirements for disposal, says Public Health Professor Tom Novotny after a San Diego State University (SDSU) study revealed filter-tipped cigarette butts to be toxic to marine and fresh-water fish.

According to Novotny and other members of the Cigarette Butt Advisory Group, used cigarette filters ought to be classified as hazardous waste since toxins present in them harm wildlife.

“It is toxic at rather low concentrations,” Novotny explains. “Even one butt in a liter of water can kill the fish in a period of 96 hours.”

Novotny says one way of reducing the amount of cigarette filters in our environment is stronger enforcement of anti-litter laws and non-smoking areas. Fines, waste fees or special taxes are other options, if the money is used to pay for cigarette butt recycling. A third alternative is to force manufacturers to pick up the bill for clean-up costs incurred by their products.

A thrown away cigarette butt is a combination of the original plastic filter and the compounds caught by the filter while the cigarette was being smoked. The plastic makes the filter non-biodegradable and the trapped compounds are toxic until they eventually biodegrades into the environment.

According to Novotny, cigarette butts are the number one littered substance in the world and have been the number one single item picked up on beach cleanup days in San Diego for several years.

“When they unconsciously throw their butts onto the ground, it’s not just litter, it’s a toxic hazardous waste product,” Novotny says. “And that’s what we’re trying to say. So that may be regulated at the local or state level. And we hope people will be more conscious about what they do with these cigarette butts.”

The study was carried out by SDSU Public Health Professor Rick Gersberg.

Picture by: Chris Sanderson, in Peterborough, Ontario, Canada.

The members of the genus Synodontis, commonly known as the squeaker catfishes of Lake Tanganyika, evolved from a single common ancestor according to a paper* published in a recent issue of the Journal of Evolutionary Biology.

synodontis catfish

Researchers Day, Bills and Friel** analysed 1697 base-pair sequences consisting of nuclear (ribosomal protein-codin gene S7), mitochondrial (cytochrome b) and transfer RNA gene fragments in 65 samples (representing about 40 species) of squeaker catfishes to study the evolutionary relationships of the group.

Through their research, the authors were able to track down a single origin for the Lake Tanganyika species flock. The members of the genus Synodontis all evolved within the last 5.5 million years which makes them a comparatively new addition to this Great Rift Valley Lake which is believed to be at least 9 million, perhaps even 12 million, years old.

Day, Bills and Friel also recovered a monophyletic group of southern African riverine species which seems to have diversified very rapidly (during the last 890,000 years). This group was believed to have been formed due to adaptive radiation within Lake Makgadikgadi; a lake which is now extinct.

* Day, JJ, R Bills & JP Friel (2009) Lacustrine radiations in African Synodontis catfish. Journal of Evolutionary Biology 22, pp. 805–817.

**Julia Day, Roger Bills and John Friel

Two new species of the genus Leporinus has been described from the Araguaia-Tocantins River system in the Amazon basin: Leporinus unitaeniatus and Leporinus geminis.

Brazilian ichthyologists Julio Garavello and Geraldo Santos describe them both in a paper* published in the most recent issue of Brazilian Journal of Biology.

Leporinus unitaeniatus

Leporinus unitaeniatus derives its name from its distinguishing colour pattern; uni is the Latin word for one and taenia means ribbon. This fish is adorned with a conspicuous longitudinal dark brown bar along the lateral line on the flanks. Other distinguishing characteristics are the slender and elongated body, the narrow snout, and the small eyes. The mouth is sub-inferior and filled with elongated, incisor-like teeth forming a straight cutting edge. There are 42–44 lateral line scales; 6 scale rows above and 5 scale rows below the lateral line; and 16 circumpeduncular scales.

Picture credit: http://www.scielo.br

Leporinus geminis

Juvenile Leporinus geminis fish look very similar to juveniles of the close relative Leporinus unitaeniatus, hence the name Leporinus geminis. Geminius is the Latin word for twin.

Leporinus geminis is decorated with three large and vertically elongated brown blotches on the trunk and has one inconspicuous dark bar on the body. The body is deep, the snout is blunt, and the eyes are large. The mouth is sub-inferior and fitted with large incisor-like teeth forming a curved cutting edge. There are 40–42 lateral line scales; 5.5 or 6 scale rows above and 5 scale rows below the lateral line; and 16 circumpeduncular scales.

Picture credit: http://www.scielo.br

* Garavello, JC and GM Santos (2009) Two new species of Leporinus

Agassiz, 1829 from Araguaia-Tocantins system, Amazon basin, Brazil (Ostariophysi, Anostomidae). Brazilian Journal of Biology 69, pp. 109–116.

A new species of the genus Chromaphyosemion has been described by Jean-Françcois Agnèse and his co-authors in a paper* published in a recent issue of the journal Zootaxa.

The new species, who has been given the name Chromaphyosemion campomaanense, belongs to the A. calliurum species group and was collected from the the Ntem River drainage in southern Cameroon. The name campomaanense is derived from Campo Ma’an National Park, the place where the fish was found.

According to the study, Chromaphyosemion campomaanense inhabits small streams and shallow pools in the rainforest. It prefers to stay close to the river bank and stays away from deeper areas with more fast moving water.

Chromaphyosemion campomaanense differs from its close relatives by displaying an asymmetrical colour pattern on the caudal fin consisting of a yellow lower margin and a white upper margin. The body is dark blue and adorned with red spots forming horizontal rows towards the head. Posteriorly, the rows merge into vertical rows. When researchers studied the genetic make-up of this fish they found that its karyotype distinguished it from the other species of the A. calliurum species group; it was
caracterized by unusually high number of chromosomes and arms compared.

The main focus of the study was to examine the molecular phylogeny of the members of the A. calliurum species group. Using a 760 base-pair fragment of the mitochondrial cytochrome b gene, researchers found the group to be composed of 10 species:

A. ahli
A. australe
A. calliurum
A. campomaanense
A. celiae
A. edeanum
A. franzwerneri
A. heinemanni
A. lividum
A. pascheni

* Agnèse, J-F, R Brummett, P Caminade, J Catalan and E Kornobisi (2009) Genetic characterization of the Aphyosemion calliurum species group and description of a new species from this assemblage: A. campomaanense (Cyprinodontiformes: Aplocheiloidei: Nothobranchiidae) from Southern Cameroon. Zootaxa 2045, pp. 43–59.

Japanese eel (Anguilla japonica) larvae have amazing buoyancy compared to other oceanic plankton, and the reason may be a type of gelatinous goo contained within the body.

When researchers from the University of Tokyo measured the specific gravity of Japanese eel larvae, they found it to be as low as 1.019, rising to 1.043 – showing the larvae to be potentially lighter than seawater itself. (Sea water has an average specific gravity of 1.024.)

When they checked other marine creatures for comparison, such as juvenile jellyfish and the sea snail Hydromyles, their specific gravity turned out range from 1.020 to 1.425. Of 26 plankton creatures tested, the Japanese eel larva was the lightest.

The food consumed by Japanese eel larvae and many other planktons tend to be found in the greatest abundance really close to the water’s surface where there is plenty of light. The low specific gravity may therefore increase the survival rate of Japanese eels by making it easier for them to find a lot of things to eat.

So, why does the Japanese eel float so well? According the Japanese study, the answer may rest in gelatinous goo – or more specifically in a matrix of transparent gelatinous glycosamino-glycans. Controlled by osmoregulation through the chloride cells that cover the body of a Japanese eel larva, this marvellous adaptation makes it possible for the larva to stay close to the surface. Researchers have also suggested that it might help the larva to stay away from predators.

For more information, see the paper: Tsukamoto K, Yamada Y, Okamura A, Kaneko T, Tanaka H, Miller MJ, Horie N, Mikawa N, Utoh, T and S Tanaka (2009) – Positive buoyancy in eel leptocephali: an adaptation for life in the ocean surface layer. Marine Biology, vol. 156, no. 5. pp. 835-846.

A recent study on intersex abnormalities in fish living in the Potomac River watershed carried out by researchers from the U.S. Fish and Wildlife Service and the U.S. Geological Survey showed that at least 82 percent of male smallmouth bass and in 23 percent of the largemouth bass had immature female germ cells (oocytes) in their reproductive organs. This number is even larger than anticipated.

This type of intersex indicates that the fish has been exposed to estrogens or chemicals that mimic the activity of natural hormones. The condition is believed to be caused by hormone-like chemicals, so called endocrine disruptors, found in medicines and a variety of consumer products. Earlier, researchers suspected that the contaminants were entering the Potomac from the wastewater treatment plants that discharge into it, but further sampling showed that the problem existed in areas located upstream from sewage plants as well. Officials are now investigating if multiple chemicals, and not just those from sewage plants, may be responsible. A larger study that includes the entire Potomac River and other East Coast rivers will be launched to find out how widespread the problem actually is.

“At the moment we don’t know the ecological implications of this condition and it could potentially affect the reproductive capability of important sport fish species in the watershed,” said Leopoldo Miranda, Supervisor of the U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office.

The Potomac River is the fourth largest river along the Atlantic coast of the USA (in terms of area), with a length of approximately 665 km (383 statute miles) and a drainage area of roughly 38,000 km² (14,700 square miles). It flows into the Chesapeake Bay along the mid-Atlantic coast of the U.S. The river is shared by West Virginia, Maryland, Virginia, and District of Columbia, and all of Washington, D.C., the nation’s capital city, lies within the Potomac watershed.

More information is available in the Intersex fact sheet released by the U.S. Fish and Wildlife Service’s Chesapeake Bay Field Office.

Madagascar, a large island situated in the Indian Ocean off the south-eastern coast of the African continent, is home to an astonishing array of flora and fauna. Madagascar, then part of the supercontinent Gondwana, split from Africa about 160 million years ago and became an island through the split from the Indian subcontinent 80-100 million years ago.

Madagascar is now the 4^th largest island in the world and its long isolation from neighbouring continents has resulted in an astonishingly high degree of endemic species; species that can be found nowhere else on the planet. Madagascar is home to about 5% of the world’s plant and animal species, of which more than 80% are endemic to island. You can for instance encounter Appert’s Tetraka bird (Xanthomixis apperti), the carnivorious Fossa (Cryptoprocta ferox) and over 30 different species of lemur on Madagascar. Of the 10,000 plants native to Madagascar, 90% are endemic.

The diverse flora and fauna of Madagascar is not limited to land and air; you can find an amazing array of creatures in the water as well – including a rich profusion of endemic fish species. Unfortunately, the environment on Madagascar is changing rapidly and the fish – just like most of the other creatures – risk becoming extinct in the near future.

The fishes of Madagascar currently have to deal with four major threats:

• Deforestation
• Habitat Loss
• Overfishing
• Invasive species

In a response to this, and to educe people around the world about the fish of Madagascar, aquarist Aleksei Saunders have created the website Madagascar’s Endangered Fishes on which he shares his knowledge of Madagascan fish species and the perils they’re facing, but also highlights all the things we can do to improve the situation.

The site focuses on freshwater fish conservation and captive breeding, since collection of wild fish to bring endangered species into captivity for managed reproductive efforts plays a large part of the conservation effort in Madagascar.

In addition to the website, Alex is also gives power-point presentations on husbandry and conservation breeding of Madagascar’s endemic fish fauna, since more and more aquarists around the world are taking a large interest in doing their part to help endangered fish species.

Alex has worked with fish since 1990 and it was through his work as an aquarist at Denver Zoo he became enthralled with the ichthyofauna of Madagascar. During the early 1990s Denver Zoo started a conservation program with the endemic freshwater fishes of Madagascar and in 1998 Alex got the chance to pay his first, but certainly not last, visit to the island. Today, his trips primarily focus on educating the Malagasy on their wonderful natural heritage and ways of conserving it, assessing the condition of native freshwater habitats and the fish population therein, and collecting wild fish for managed captive breeding. Alex now manages on of the most diverse collections of Madagascan endemic fishes in North America, including 5 species of rainbowfish, 4 species of cichlid, and 3 killifish species.

With this site I hope to educate, motivate, and stimulate people into action to help save Madagascar’s endangered fishes. Please look around the site. There are sections for fish hobbyists, adventure travellers, conservation biologists, and just those curious about the world in which we live.

Cheers,

Aleksei Saunders

Since the first specimens were spotted in the year 2000, the number of lionfish living off the coast of North Carolina is now so high that scientists fear it is too late to eliminate them. Instead, marine researchers are joining forces with sport divers and cooks to keep the fish population in check the old fashion way – with rice, spicy sauce and a slice of lemon.

The lionfish has a sweet meat that tastes similar to that of the appreciated food fishes like the snapper and the grouper. If you want to help save the native North Carolinian fauna by putting lionfish on as many dinner plates as possible, there are several things you can do.

For all you scuba divers, Discovery Diving Co. in Beaufort and Olympus Dive Center in Morehead City are recruiting sport divers for a series of “lionfish rodeos” that will take place during the summer dive season. The first event is planned to May 18 and 19, and new events will then be held regularly throughout the summer.

During the first lionfish rodeo, participating divers will be thought how to collect lionfish in a safe way using protective gloves. In addition to getting some lionfish off the reefs and provide all participants with a tasty meal, the rodeo will also give marine researchers a chance to study how rapidly lionfish repopulate an area after being vanquished.

In addition to divers and marine researchers, representatives of the Carteret Community College culinary school will be involved in the rodeo project. One of their main goals is to persuade restaurants in the area to start serving lionfish, so those of you that don’t dive can still help out by asking for lionfish when dining out.

“They taste good, and if we can create a food market for them maybe that will not only help keep them in control but maybe take the pressure off some other species,” sais Debby Boyce, owner of Discovery Dive Shop.

The lionfish is not a welcomed guest in North Carolina since it competes with native species for space and food and puts even more stress on already threatened fish like snappers and groupers. The lionfish seem to lack natural predators in western Atlantic waters because the lionfish population has increased at a pace unlike anything scientists have ever seen from an invasive fish species in this part of the world.

“In places off North Carolina the population density appears to be several times the norm in their native waters”, said NOAA researcher James Morris.

North Carolina is not the only state with an exploding lionfish problem on their hands; the species can now be found in large quantities all the way down into the Caribbean.

“They’re eating everything,” said Lisa A. Mitchell, executive director of Reef Environmental Education Foundation, a Florida non-profit group that is helping several Caribbean governments deal with invasive lionfish. “They could wipe out entire reefs.

The lionfish is not only a problem for native flora and fauna; it is also disliked among snorkelers and scuba divers since it is equipped with long spines capable of delivering a painful venomous sting. The venom itself it usually not lethal, but it can cause paralysis and excruciating pain – two things you definitely don’t want to suffer from while trying to get up from the deep.

In North Carolina ordinary swimmers and snorkelers rarely have to worry about lionfish since this tropical species prefer to stay in the warm waters of the Gulf Stream, i.e. miles offshore and mostly at depths of at least 100 feet. In the warmer places like the Caribbean you can on the other hand encounter lionfish in the shallows right next to the beach.

In North Carolina it is usually the scuba divers who see this fish and they are alarmed by the situation. Divers off the North Carolina coast now routinely find up to 100 lionfish during a single wreck dive.

“If you go deeper than 100 feet, they’re ubiquitous now,” said Paula Whitfield, a researcher with the National Oceanic and Atmospheric Administration (NOAA) in Beaufort. “They’re absolutely everywhere.”

Catching lionfish is labour intensive but not very difficult; all you need is a net or a spear and some protective clothing to keep yourself from being stung. The divers organized by Discovery Diving Co. in Beaufort and Olympus Dive Center in Morehead City will be fitted with the kind of puncture-proof gloves worn by workers who handle used hypodermic needles and other medical waste. Before the lionfish is cleaned and cooked it will be held down using pliers and have its venomous spines snipped off by a wire cutter.

Lionfish is not very hard to net or spear-fish since they are virtually fearless and will hold their ground even when approached by divers. Since they have so few enemies in the wild, they probably don’t see any point in fleeing. However, if we are to really eat our way out of the lionfish problem a less labour intensive method than sending down divers armed with spears and nets must naturally be developed and NOAA researchers are therefore currently working on a trap system that uses live bait.

Hopefully, we will soon see the invasive lionfish on dinner tables all the way along the western Atlantic.