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The bramble is a large (to 4 meters), wide-ranging deepwater shark of cold-temperate to tropical seas. Compagno (1984) notes that the distribution is spotty but the genus has been reported circumglobally, inhabiting continental and insular shelves and slopes from 11 to 900 meters. Usually found near the bottom, it's known to feed on fish, crabs and cephalopods. Of the two extant species, one is circumglobal, Echinorhinus brucus BONNATERRE 1788 and the other, E. cookei PIETSCHMANN, 1928, limited to the Pacific. E. cookei bears only the small (less than 5 mm in diameter) stellate denticles illustrated in many publications, while E. brucus bears fewer and larger denticles which have a rounded base; the attached image (fig. ) of E. brucus denticles suggests this observation needs qualification.
Viewing the published literature, there is some dentition / tooth-design detail given for the genus (i.e., Garman 1913:243, Bigelow & Schroeder 1948:527-29 and Cappetta 1987:51) but no characteristics that might provide a means of distinguishing between the extant species or differentiating them from the fossil taxon E. blakei. A synthesis of observations includes:
monognathic heterodonty
10-12 files / quadrate
labio-lingually compressed tooth with a primary cusp which is distally directed forming an obtuse angle with the first mesial cusplet
1-2 mesial and distal cusplets which may be positionally (anterior or posterior-most) or ontogenetically (young) absent
weak serrations may be present.
The Fossil Record
Fossil brambles are known only from isolated, but distinctive, teeth and denticles. Cappetta notes numerous fossil occurences and species beginning with the Upper Cretaceous of Angola. Cenozoic brambles have been reported from Europe, Africa and the Americas (North and South). Some of the species he lists include:
E. blakei AGASSIZ, 1856 (Miocene of California),
E. caspius GLICKMAN 1964 (Oligocene of former USSR & California),
E. priscus ARAMBOURG 1952 (Lower Eocene, Morocco) and
E. weltoni PFEIL 1983 - (Upper Eocene, Oregon).
Kent (1994) includes E. priscus as present in the Eocene of Virginia, and E. blakei from the Miocene of Maryland, North Carolina and California.Purdy, et al (2001) noted great similarites and suggested that E. cookei may be a junior synonym of E. blakei.
Echinorhinus priscus ARAMBOURG 1952
Echinorhinus blakei AGASSIZ, 1856
REFERENCES
Bigelow, H. B. and W. C. Schroeder 1948. Part 1. Sharks; in Fishes of the western North Atlantic. Sears Foundation for Marine Research, Yale University, New Haven.
Cappetta, H., 1987. Chondrichthyes II. Mesozoic and Cenozoic Elasmobranchii. In: Handbook of Paleoichthyologie, vol. 3b, Gustav Fischer Verleg, Stuttgart, 193 pp.
Compagno, L.,1984. FAO Species Catalogue, Vol 4, parts 1 & 2 Sharks of the World. United Nations Development Program.
Garman, S. 1913. The Plagiostomia (Sharks, Skates and Rays). Memoirs of the Museum of Comparative Zoology at Harvard College, 36:528 pages. Reprinted by Benthic Press (1997), Summers A. P. ed.
Kent, B. W. 1994. Fossil Sharks of the Chesapeake Region. Egan Rees & Boyer, Maryland. 146 pp.
Purdy, R., Schneider, V., Appelgate, S., McLellan, J., Meyer, R. & Slaughter, R., 2001. The Neogene Sharks, Rays, and Bony Fishes from Lee Creek Mine, Aurora, North Carolina. In: Geology and Paleontology of the Lee Creek Mine, North Carolina, III. C. E. Ray & D. J. Bohaska eds. Smithsonian Contributions to Paleobiology, No 90. Smithsonian Institution Press, Washington D.C. pp. 71-202.
Welton, B., 1979 Late Cretaceous and Cenozoic Squalomorphii of the Northwest Pacific region. - Unpubl. Ph. D. thesis, Univ. Calif.Berkley, 553 pp.
Other Site References
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Lee Creek Bramble Sharks by Bill Heim |
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