Not just Shark Pictures:
Elasmodiver contains photos of sharks, skates, rays, and chimaera's
from around the world. It began as a simple web based field guide to
help divers find the best places to encounter different species of
sharks and rays but it has slowly evolved into a much larger project
containing information on all aspects of shark diving and
photography. There are now more than a thousand shark pictures
and sections on shark evolution, biology, and conservation. There is
a large library of reviewed shark books, a constantly outdated shark
taxonomy page, a monster list of shark links, and deeper in the site
there are numerous articles and stories about shark encounters.
Elasmodiver is now so difficult to check for updates, that new
information and pictures are listed
on an Elasmodiver Updates Page that
can be accessed here:
If you're
looking for a broader range of marine life pictures the following
links represent a new area that contains pictures on other marine
organisms and on marine habitats. This expansion of Elasmodiver is
in its first stages but will eventually include pages on everything
from sea stars to nudibranches. Creating this portal will take time
and for now it consists of a token offering of fish pictures. Please
return regularly to enjoy the progress.
The Banded
wobbegong Orectolobus halei (originally described by Whitley in
1940) has been redescribed by Huveneers in 2006. It was previously
considered to be the adult form of the Ornate Wobbegong Orectolobus
ornatus.
Banded Wobbegong image Andy Murch
Himantura kittipongi
New species of
freshwater stingray discovered in Thailand
Bangkok, Thailand – A new
species of freshwater stingray has been discovered in a river in western
Thailand, but its chances for long-term survival are slim, warns WWF.
The new species of stingray,
measuring 60 centimeters (23.6 inches) in width, was first observed two
years ago but has only now been confirmed in detail as a new species by
researchers from WWF Thailand and the US-based Smithsonian Institute.
WWF Thailand’s Senior
Freshwater Biologist, Dr Chavalit Vidthayanon, along with Smithsonian
Research Associate Dr Tyson Roberts, have described in detail the new
freshwater stingray, known as Himantura kittipongi, found in the Mekong
Basin of western Thailand.
Thai rivers, including the
Mekong River where the ray is found, have been plagued by serious
pollution, overfishing and dam building, which have taken a deadly toll on
Thailand's once diverse and abundant river life. The ray is believed to
exist in only small numbers.
The new species was named Himantura kittipong after prominent Thai fish
expert Kittipong Jaruthanin who first observed the ray in 2004.
For more information: Radda Larpnun, Communications Manager
WWF Thailand
Email:
radda@wwfthai.org
Sphyrna sp.
Previously unknown species of hammerhead shark discovered
BY SUSAN COCKING
Knight Ridder Newspapers
MIAMI - Scientists from Nova Southeastern University and the University of
South Carolina have discovered a previously unknown species of hammerhead
shark in the southeastern Atlantic.
The species - as yet unnamed - so closely resembles the scalloped
hammerhead
(Sphyrna lewini) that the only ways to tell them apart are to compare DNA
and
count vertebrae.
Mahmood Shivji, director of the Guy Harvey Research Institute at the NSU
Oceanographic Center in Dania Beach, says the two species share the same
waters but do not interbreed. Shivji adds that the cryptic, or
unrecognized
species, may be less abundant than the scalloped, making it more
susceptible
to fishing pressure.
''They're catching these things they don't know they're catching,'' Shivji
said. ``You could wipe out a whole genetic lineage if you are not managing
these species separately.''
Hammerhead sharks, of which there are believed to be eight species, occur
worldwide. In U.S. waters, hammerheads are managed under the umbrella of
11
large coastal shark species - not including those on the federal
prohibited
species list. Commercial fishing for large coastal sharks is regulated
through
seasons and quotas.
The practice of finning - cutting off a shark's fins and discarding the
carcass - is illegal in the United States but widely practiced around the
world because fins are believed to have aphrodisiacal and medical
benefits.
Hammerheads are particularly vulnerable because their fins are worth
hundreds
of dollars per kilogram at markets in the Far East, while their meat is
much
less valued. As a result, hammerhead abundance in the western Atlantic is
believed to have declined by 89 percent since the mid-1980s, according to
a
study by researchers at Canada's Dalhousie University published in the
journal
Science in 2003.
TRAILBLAZERS
Shivji and his NSU colleagues are at the forefront of using genetics to
identify sharks exploited in the international fin trade, which is how
they
stumbled on the previously unknown species of hammerhead. In trying to
develop
a DNA forensic marker for scalloped hammerheads, they collected 143
samples of
Sphyrna lewini from around the world. They were puzzled to find that the
test
worked on all the sharks except for three, which were caught by
recreational
anglers off Fort Lauderdale.
At first, the scientists thought something was wrong with their forensic
marker. But more extensive testing on the three South Florida sharks
showed
their DNA was completely different from all other scalloped hammerheads
caught
locally and around the world, suggesting a separate species.
''The genetic difference is greater between the new cryptic species and
the
regular scalloped hammerhead than between the geographically separate
populations of the scalloped hammerhead,'' Shivji said.
SIMILAR RESULTS
The startling discovery didn't create much of a stir at first. But
coincidentally, scientists at the University of South Carolina came to the
same conclusion, using genetic testing to separate eight anomalous sharks
caught in their coastal waters. In a paper published online last December,
they suggested that bays in their state serve as nurseries for the cryptic
species, and should be protected. Intense fishing pressure, they warned,
could
imperil both the scalloped hammerhead and the new species.
The scientists wrote: ``Concentrated reproduction in South Carolina
coastal
waters also could increase the risk of extinction of the cryptic species.
. .
. Data on the geographic distribution and relative abundance of both
scalloped
hammerhead species is critical at this juncture and should be used to
evaluate
current management plans.''
It is too soon to tell how the discovery of the previously unknown
hammerhead
could affect shark management. NOAA Fisheries research biologist Enric
Cortes,
who prepares shark-stock assessments for the U.S. east coast, calls the
news
``shocking -- it will be another curveball that will be thrown at us.''
Cortes says it will be difficult to separate the new hammerhead in stock
assessments because it can only be recognized genetically. More likely, it
would be lumped with the other large coastal sharks.
Meanwhile, Shivji said, more research is required to count and describe
it.
Said Shivji: ``This is the next project that needs to be done: What
population
of scalloped hammerheads are the new cryptic species? Someone has to do
the
taxonomy on this and give it a name.''
Mustelus hacat
Pérez Jiménez, Juan
Carlos, Nishizaki, Oscar Sosa, Castillo Geniz, José Leonardo A New Eastern North Pacific Smoothhound Shark (Genus Mustelus,
Family Triakidae) from the Gulf of California
Copeia 2005 2005: 834-845
MEXICO: March 3, 2006
MEXICO CITY - A Mexican marine biologist has discovered a new shark
species in the murky depths of Mexico's Sea of Cortez, the first new
shark find in the wildlife-rich inlet in 34 years.
Postgraduate student Juan Carlos Perez was on a fishing boat in early
2003 studying sharks from the Mustelus family netted at depths of 660
feet (200 meters) when he noticed some of them had darker skin and white
markings.
The sharks, slender, dark gray-brown and around 5 feet (1.5 meters)
long, turned out to be a new species that Perez and his team have named
"Mustelus hacat," after the word for shark in a local Indian dialect.
"What I first noticed was their color. They are dark in color, like dark
coffee, and have white markings on the tips and edges of their fins and
tails which jump out at you because they are so dark," Perez told
Reuters on Thursday.
"I got back from the boat and the first thing I said was that I thought
I had a new species, but I wasn't sure until six months on when we did
genetic tests," he said, audibly elated.
Perez studied around 40 of the sharks from 2003 to 2005.
Worldwide, marine biologists tend to discover two or three new shark
species in any given year.
But Perez's find -- bringing to five the types of Mustelus shark found
in the eastern North Pacific -- is the first shark discovery in the Sea
of Cortez since the tiny Mexican Horn Shark (Heterodontus mexicanus) was
identified in 1972.
"I wasn't looking for something new, but it's very satisfying. I'm very
happy," said Perez, 31, who is based at the CICESE science and
technology research center at the port of Ensenada in northwestern Baja
California state.
His find was published in the US journal Copeia in December.
"There must be more undiscovered species there but access is difficult.
If we hadn't been on those boats I'd never have seen them because that's
the only place they are caught. And it's not a region that attracts
scuba diving."
There are some 50 to 60 species of shark in the Sea of Cortez, a narrow
body of water also known as the Gulf of California that separates
Mexico's Baja California peninsula from the mainland and is famous for
its rich and unique ecosystem.
The Mustelus hacat lives in the ocean's depths feeding on shellfish and
shrimp," Perez said, adding: "They have very, very small teeth. They are
really not aggressive or dangerous."
New species of shark discovered in Australia
http://www.practicalfishkeeping.co.uk/pfk/pages/item.php?news=762
Scientists have described a new species of shark in the waters of
northern Australia.
The new Weasel shark has just been named Hemigaleus australiensis
in a paper in the systematics journal Zootaxa, and is only the
second known member of the genus.
The description, written by William White of Murdoch University, Perth,
Peter Last of CSIRO and Leonard Compagno of the Shark Research Centre,
Cape Town, says that the new Hemigaleus species differs from its
congener, H. microstoma, in the presence of a black mark on the
tip of the second dorsal fin, as well as having far fewer vertebrae and
lots more teeth on its lower jaw.
The new fish Hemigaleus australiensis, which is a member of the
Carcharhiniformes family Hemigaleidae, is known from inshore bays on the
continental shelves of northern Australia and lives in water up to
170m/557’ deep.
Its closest relative, H. microstoma, commonly known as the the
Weasel shark or Sicklefin weasel shark, is a small and slender species
roughly the same shape and size as the Smooth hound sharks, Mustelus
spp. native to UK waters, which reaches around 1m/39” in length.
H. microstoma is relatively common in the waters around
Indonesia, Thailand and Singapore and has paler fins often with white
spots on the tips of the fins and the flanks. It lacks the black mark
seen on the second dorsal of australiensis.
H. microstoma feeds on crustaceans and cephalopods, particularly
octopuses, and is often caught as a food species.
For more details on the new shark species see the paper: White, WT.,
Last, PR. and JV Compagno (2005) – Description of a new species of
weasel shark, Hemigaleus australiensis n. sp. (Carchariniformes:
Hemigaleidae) from Australian waters.Zootaxa 1077: 37-49.
Matt Clarke: Mon November 7, 2005, 3:12 pm
Pastinachus solocirostris
MALAY ARCHIPELAGO:
September 2005
New stingray described
A new species of marine stingray has been described from
the waters of the Indo Malay archipelago.
The new fish, which has been named Pastinachus solocirostris, has just
been described by Peter Last, Mabel Manjaji and Gordon Yearsley in a
paper in the systematics journal Zootaxa.
Pastinachus solocirostris is a member of the Dasyatidae family and sits
in the Order Mylobatiformes.
The genus Pastinachus was previously considered to be monotypic, with a
single representative species, P. sephen, occuring across a wide area of
the Indo Pacific from the Red Sea to China.
However, recent studies have found a number of distinct fishes in the
genus and it seems likely that many names that have previously been
placed into synonymy will be raised to specific status once again.
The new ray was discovered in Indonesia and Malaysian Borneo but appears
to occur mainly in muddy waters and estuaries off Borneo and Sumatra.
Unlike other members of the genus, P. solocirostris has a smaller adult
size, a more elongate head and disc shape, fewer pectoral fin radials
and vertebrae and a sting closer to the end of its tail.
For more details on the new stingray species see the paper: Last, PR.,
Manjaji, BM and GK Yearsley (2005) - Pastinachus solocirostris sp. nov.,
a new species of Stingray (Elasmobranchii: Mylobatiformes) from the
Indo-Malay Archipelago. Zootaxa 1040: 1-16. Matt Clarke: Tue September 27, 2005, 8:42 am
