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.

The discovery of three new species of fossilized octopi in Lebanon has caused scientists to suspect that the first octopus appeared tens of millions of years earlier than previously thought.

In a paper published in a recent issue of the journal Palaeontology, researchers Fuchs, Bracchi and Weis describes three new species of fossil octopus placed in two new genera: Keuppia and Styletoctopus. The species have been given the names Keuppia levante, Keuppia hyperbolaris and Styletocopus annae.

The descriptions are the result of the fortunate discovery of three astonishingly well preserved octopus fossils from the Cenomanian, i.e. octopus that lived at some point between 93 and 100 million years ago.

Studying the history of octopi is difficult since the octopus, unlike dinosaurs for instance, is composed almost entirely of soft tissue; predominantly muscle, skin and viscera. When an octopus dies the body rapidly decomposes and vanishes, and extraordinary conditions are necessary for the animal to leave any fossil record behind.

Fortunately for science such extraordinary conditions must have been at hand in Lebanon some 100 million years ago, because the three newfound fossils are so well preserved that even traces of muscles, suckers, internal gills and ink can be distinguished.

This type of fossil is so rare that Mark Purnell, for the Palaeontological Association, remarked that finding an octopus as a fossil “is about as unlikely as finding a fossil sneeze”.

Before these three species were discovered, only one species of fossil octopus was known to science.

For more information, see the paper published in Palaeontology: Fuchs, D, G Bracchi and R Weis (2009) New Octopods (Cephalopoda: Coleoidea) from the Late Cretaceous (Upper Cenomanian) of Hakel and Hadjoula, Lebanon. Palaeontology 52, pp. 65–81.

In a study announced today by the Wildlife Conservation Society* (WCS) at the International Coral Reef Initiative** (ICRI) meeting in Thailand, researchers show that some coral reefs located off East Africa are unusually resilient to climate change. The high resilience is believed to be caused by geophysical factors in combination with improved fisheries management in these waters.

After studying corals off the coast of Tanzania, researchers found that these coral reefs has made an incredibly speedy recovery from the 1998 bleaching event that wiped out up to 45 percent of the region’s corals. The authors of the study attribute the swift recovery to a combination of reef structure and reef management.

Compared to many other coral reefs around the world, Tanzania’s reefs are used to considerable variations in both current and water temperature which has turned these reefs into an unusually complex web of different coral species. This bio-diverse ecosystem includes several different species known to quickly re-colonize an area after a bleaching incident.

The authors of the study believe that reefs in other parts of the world subjected to similarly diverse environmental conditions might have the same high ability to recover from large-scale climatic and human disturbances. The study provides additional evidence that such “super reefs” can be found in the triangle from Northern Madagascar across to northern Mozambique to southern Kenya and the authors suggest that these reefs should be a high priority for conservation efforts since they may come to play an important global role in the future recovery of coral reefs worldwide.

“Northern Tanzania’s reefs have exhibited considerable resilience and in some cases improvements in reef conditions despite heavy pressure from climate change impacts and overfishing,” says Dr. Tim McClanahan***, the study’s lead author. “This gives cause for considerably more optimism that developing countries, such as Tanzania, can effectively manage their reefs in the face of climate change.”

The study also stresses the impact of direct management measures in Tanzania, including closures to commercial fishing. Algae is known to easily smother corals, but researchers found how areas with fishery closures contained a rich profusion of algae eating fish species that kept the corals clean. The few sites without any management measures remained degraded, and in one of them the population of sea urchins had exploded. Sea urchins feed on corals and can therefore worsen the problem for an already suffering reef.

The study has been published in the online journal Aquatic Conservation: Marine and Freshwater Ecosystems.

Authors of the study include Tim McClanahan and Nyawira Muthiga of the Wildlife Conservation Society, Joseph Maina of the Coral Reef Conservation Project, Albogast Kamukuru of the University of Dar es Salaam’s Department of Fisheries Science and Aquaculture, and Saleh A.S. Yahna of the University of Dar es Salaam’s Institute of Marine Sciences and Stockholm University’s Department of Zoology.

* The Wildlife Conservation Society is an institutional partner to ICRI and is actively conserving tropical coral reef species in priority seascapes in Belize, Indonesia, Papua New Guinea, Fiji, Kenya and Madagascar. Along with monitoring reefs, WCS also trains of park staff in protected areas.

** The International Coral Reef Initiative (ICRI) is a global partnership among governments and organizations working to stop and reverse the degradation of coral reefs and related ecosystems. This ICRI General Meeting was convened by the joint Mexico – United States Secretariat.

*** Dr. McClanahan’s research regarding ecology, fisheries, climate change effects, and management of coral reefs at key sites throughout the world is supported by the Western Indian Ocean Marine Science Association (WIOMSA) and The Tiffany & Co. Foundation.

After a 1,100-mile voyage and more than ten years of planning and acquiring funding resources, the ex-military ship Gen. Hoyt S. Vandenberg finally arrived in Key West this Wednesday.

The ship is scheduled to be sunk sometime between May 20 and June 1 and will eventually form the second largest artificial reef in the world. The ship will rest some six miles south of Key West in 140 feet of water in the Florida Keys National Marine Sanctuary.

“We’re all pretty excited here in Key West and particularly in view of the fact this is going to be the second largest artificial reef in the world,” said Key West City Commissioner Bill Verge, who is serving as a project liaison between the city and various state and federal agencies.

“One of the big products that we make here is happy vacations,” said Joe Weatherby who conceived the project some 13 years ago. “And we feel that this artificial reef is the world’s best product ever produced for scuba diving. People are going to come from all over the world to dive this, but this product also has been designed so we can offer it to glass bottom boat riders, snorkelers or new divers as well as advanced divers, it holds interest for all of them.”

The Vandenberg is now undergoing final preparations before the scuttling and is for instance fitted with several hundred big holes along its decks and sides to prevent it from falling over as it sinks. The ship has already been ridded from potentially dangerous materials by two Norfolk, Va., shipyards who removed 71 cubic yards of asbestos, 193 tons of materials that contained potentially carcinogenic substances, 46 tons of refuse, 300 pounds of mercury-containing materials and 185 55-gallon drums of paint chips. The cleaning required 75,000 man-hours and used up 70 percent of the projects $8.6 million US dollars.

The artificial reef is becoming a reality thanks to the cooperation of a lot of different people and entities. It is funded by Monroe County, the Florida Governor’s Office of Tourism, Trade and Economic Development; City of Key West, U.S. Maritime Administration, Florida Fish and Wildlife Conservation Commission, Florida Keys & Key West tourism council, the National Oceanic and Atmospheric Administration as well as by industry and private donations. Banks that provided loans include First State Bank of the Florida Keys, BB&T and Orion.

As of now, you can find the Vandenberg docked behind the USS Mohawk at the East Quay Wall in Truman Annex Harbor. The USS Mohawk is a historic Coast Guard ship open as a floating museum.

History of the Gen. Hoyt S. Vandenberg

This ship has not always been known under the name Gen. Hoyt S. Vandenberg; it used to be a U.S. Army troop transport named the General Harry Taylor. In 1963 it got its new name, the Gen. Hoyt S. Vandenberg, as it began tracking the U.S. space program’s launches off Cape Canaveral. Vandenberg has also been used for monitoring U.S. defense missile test launches in the Pacific as well as eaves dropping on Russian missile launches during the Cold War. Its last active duty homeport was Port Canaveral in Florida, from 1976 to the ships formal retirement in 1983.

In 1983, the Vandenberg was moved to the James River Naval Reserve Fleet. Even though it had been formally retired, it was still kept in a state of readiness in case it would be needed again. Every six months, technicians would power up all its electronics and make any necessary repairs. It was kept like this for 10 years until it was formally struck from the naval register in 1993 and transferred to the Maritime Administration.

After this, the ship began a new life and did for instance serve as a Russian science ship in the 1999 movie “Virus,” where it played its part alongside Hollywood stars like William Baldwin, Jamie Lee Curtis, and Donald Sutherland.

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.

Fish females subjected to stress produce highly active offspring but the risk of abnormalities also increases, according to new research carried out by Dr Monica Gagliano, a research fellow with the AIMS@JCU joint venture, and Dr Mark McCormick from the ARC Centre of Excellence for Coral Reef Studies at the James Cook University.

The research focused on the Ambon damsel fish (Chromis amboinensis), a common reef species in the Indo-Pacific, and has deepened our understanding of how stress factors affect not only the adult fish themselves but also their offspring. Being more active than normal affects survival and more active offspring will therefore have important implications for fish populations in a changing environment.

In their laboratory testing, Dr Gagliano and Dr McCormick exposed fertilized Ambon damsel eggs gathered from the wild to various amounts of the stress hormone cortisol. Previous studies have shown that female Ambon damsels release cortisol from their ovaries when subjected to environmental stress. Fish that lived on reefs with few predatory fish around and little competition released less cortisol than those who lived in environments where they had to deal with a lot of competition and predators.

In addition to making the offspring more active, high doses of cortisol also increases the risk of developmental defects.

“If the mother fish is more stressed and she passes on more cortisol, then the offspring will have a faster developmental rhythm and therefore errors will be more likely in their development. One likely result of this is that the offspring are born asymmetrical,” Dr Gagliano said.

“These baby fish can’t make these important hormones until later in life, so their whole initial development is determined by hormones they obtain from their mothers,” Dr McCormick added.

Developmental errors can naturally cause serious problem for fish and lower their chances of survival. In 2008, Dr Gagliano and her colleagues showed that fish born with asymmetrical ear bones have a hard time handling the open ocean stage of their life and that a large percentage of these fishes die before being able to find a reef to settle on. The asymmetry hurts the fish’s hearing ability and makes it difficult for it to pick up reef-related sounds.

In her new research project, Dr Gagliano has been able to show that maternal stress has a large measurable effect on the shape of ear bones. Offspring subjected to a high dose of cortisol are more than twice as likely to have asymmetrical ear bones compared with those that received no dose of cortisol.

You can find more information in the study published in Oecologia.