NEWSLETTER 1/2009 07. October. 2009
NEW PARTNER:
# Dr. Farid Hemida, Enssmal, Dely Ibrahim, Algiers, Algeria, E-Mail: faridhemida@gmail.com
# Dr. John D. Stevens, Hobart, Australia
# Dr. Stefanie Klug, Staatliches Museum für Naturkunde Stuttgart, Stuttgart, Germany
# Dr. Jürgen Kriwet, Staatliches Museum für Naturkunde Stuttgart, Stuttgart, Germany
# Markus Dorka, Berlin, Germany
# Dr. Spencer G. Lucas, New Mexico Museum of Natural History, Albuquerque, New Mexico, USA
# Dr. Gregor Cailliet, Moss Landing Marine Laboratories, California, U.S.A.
# Mike Everhart, Sternberg Museum of Natural History, Fort Hays State University, Hays, U.S.A.
# Heike Zidowitz, Deutsche Elasmobranchier-Gesellschaft e.V., Hamburg, Germany
# Shawn A. Hamm, Department of Geosciences, University of Texas, Dallas, U.S.A.
LAST UPDATES:
186 new data, 71 new analysed papers
NEXT UPDATE:
Sunday, 11. October 2009 (22:00)
NEW PAPERS:
WHITE, W.T. & COMPAGNO, L.J.V. & DHARMADI, 2009, Hemitriakis indroyonoi sp. nov., a new species of houndshark from Indonesia (Carcharhiniformes: Triakidae). Zootaxa, 2110: 41-57
new species: Hemitriakis indroyonoi
SÉRET, B. & LAST, P.R., 2009, Notoraja sapphira sp. nov. (Rajoidei: Arhynchobatidae), a new deepwater skate from the slopes of the Norfolk Ridge (South-West Pacific). Zootaxa, 2153: 24-34.
new species: Notoraja sapphira
CICIMURRI, D.J. & KNIGHT, J.L., 2010, Late Oligocene sharks and rays from the Chandler Bridge Formation, Dorchester County, South Carolina, USA. Acta Palaeontologica Polonica, 54: in press (download: www.app.pan.pl/archive/published/app54/app20080077_acc.pdf)
new species: Raja mccollumi
JOHNSON, G.D. & THAYER, D.W. 2010 Early Pennsylvanian xenacanth chondrichthyans from the Swisshelm Mountains, Arizona, U.S.A. Acta Palaeontologica Polonica, 54: in press (download: http://www.app.pan.pl/archive/published/app54/app20080051_acc.pdf)
new species: Orthacanthus donnelljohnsi, Triodus elpia
MOLLEN, F.H. 2010 A partial rostrum of the porbeagle shark Lamna Nasus (Lamniformes, Lamnidae) from the Miocene of the North Sea Basin and the taxonomic importance of rostral morphology in extinct sharks. Geologica Belgica, 13: 61-76 (download: http://popups.ulg.ac.be/Geol/document.php?id=2792)
KRIWET, J. & NUNN, E.V. & KLUG, S. 2009 Neoselachians (Chondrichthyes, Elasmobranchii) from the Lower and lower Upper Cretaceous of north-eastern Spain. Zoological Journal of the Linnean Society, 155: 316-347
new family/genus/species: Ptychotrygonidae/Platypterix, Iberotrygon/Cantioscyllium brachyplicatum, Platypterix venustulus, Ptychotrygon pustulata, Ptychotrygon striata, Iberotrygon plagiolophus
MISCELLANEOUS
Weird New Ghostshark Found; Male Has Sex Organ on Head
California has a new star, the Eastern Pacific black ghostshark. But the newly identified species prefers to stay out of the sun—and the spotlight. And with a club-like sex organ on its forehead, the male ghostshark isn't likely to get any leading man roles.
Pictured alive underwater and preserved in a museum collection, the new ghostshark uses winglike fins to "fly" through its dark habitat, thousands of feet deep off the coasts of California and Mexico's Baja California peninsula, a new study says.
The ghostshark seems to have flown under the scientific radar too. Since the 1960s experts have been finding specimens of the strange, 3-foot-long (0.9-meter-long) fish, which ended up nameless in museum collections around the world.
It wasn't until after a team recently searched through shelves of "dead pickled fish" that the Eastern Pacific black ghostshark was recognized as its own new species, said study co-author Douglas Long, chief curator in natural sciences at the Oakland Museum of California. The specimens' unique proportions, precisely measured, gave the fish away as a separate species of ghostshark.
The shark-like animal belongs to the mysterious and little-studied chimaeras, perhaps the oldest group of fish alive today.
These "living fossils" branched off from sharks about 400 million years ago. They may have survived by adapting to extreme deep-sea environments, Long said.
The newfound ghostshark belongs to the "big black chimaeras," a group whose species number has exploded in recent years, thanks to improved diagnostic techniques, according to the new study, published in the September issue of the journal Zootaxa. (1. page of the paper: http://www.mapress.com/zootaxa/2009/f/z02218p068f.pdf)
source:
http://news.nationalgeographic.com/news/2009/09/090922-ghost-shark-new-species-picture.html
Sharks swarmed on ancient sea monster
85-million-year-old plesiosaur bears the marks of great white ancestors
Sept. 17, 2009
Remains of a shark-bitten, 85-million-year-old plesiosaur reveal that around seven sharks likely consumed the enormous dinosaur-era marine reptile in a feeding frenzy, leaving some of their shark teeth stuck in the plesiosaur's bones, according to a new study.
The findings, which will be presented at next week's 69th Annual Meeting of the Society of Vertebrate Paleontology, are the first direct evidence of the diet and feeding behavior of Cretalamna appendiculata, a now-extinct early relative of today's great white sharks .
The study, which has also been accepted for publication in the Journal of Vertebrate Paleontology, further represents what lead author Kenshu Shimada describes as "arguably the most spectacular case of shark feeding on a vertebrate carcass reported to date."
Shimada is an associate professor at Chicago's DePaul University and research associate in paleontology at the Sternberg Museum of Natural History. He and colleagues Takanobu Tsuihiji, Tamaki Sato and Yoshikazu Hasegawa analyzed the shark-decimated plesiosaur, Futabasaurus suzukii, which was unearthed in central Japan and then housed at the National Museum of Nature and Science in Tokyo.
They found five C. appendiculata teeth embedded in four different bones of the plesiosaur, and additionally discovered 80 associated teeth of this same shark species with the remains. The size and shape of the teeth indicate they belonged to both juvenile and adult sharks.
Based on the physical evidence, Shimada and his team determined what likely happened to the over 30-foot-long dinosaur-like marine reptile.
"The plesiosaur inhabited the near shore, shallow sea," he told Discovery News. "Whatever the cause of its death, the plesiosaur carcass came to rest belly-side up on the bottom of the sea floor, below the reach of surface waves, where mud mixed with sand grains accumulated relatively rapidly."
"Prior to its decomposition, at least six or seven Cretalamna appendiculata individuals, possibly ranging in size from about 5 to 14 feet in length, began to scavenge the plesiosaur throughout its body. Whether or not the feeding activity took place continuously or intermittently is uncertain."
The researchers also haven't ruled out that the huge marine reptile was attacked and killed by the sharks.
"If the plesiosaur had been attacked by one or more individuals of C. appendiculata, it must have been a fatal attack because bones of the plesiosaur immediately around the embedded teeth do not show any indication of bone healing," the scientists concluded.
Thomas Williamson, curator of paleontology at the New Mexico Museum of Natural History and Science in Albuquerque, told Discovery News that the new paper isn't the first reported evidence of shark feeding on a plesiosaur, but it is "the first evidence of feeding by the shark Cretalamna appendiculata."
"It is interesting that such a large number of individuals of C. appendiculata --- six or seven --- may have participated in the predation or scavenging," Williamson said, adding that "similar numbers of modern shark species are known to behave this way."
Williamson isn't, however, convinced by the inferred position of the plesiosaur during the feeding, as he said it could have moved during the course of the shark feasting.
Shimada said he grew up reading about the plesiosaur in Japanese children's science books, and vividly remembers seeing photographs of the shark teeth in a pictorial science encyclopedia.
"It's rather amusing --- and I'm honored at the same time --- that I was given an opportunity to formally describe the very same shark teeth about 30 years later," he said.
http://www.msnbc.msn.com/id/32896206/ns/technology_and_science-science/
