Apholodotus
(Apholodotos) ossua
Class Actinoptergyii,
Order Terrasiiformes, Family Terrasiidae
Geological
Time: Mississippian (~320 m.y.a.)
Size (25.4
mm = 1 inch): Fossil is 83 mm long (tip of nose to tip of tail along
backbone) on a 205 mm by 150 mm and 145 mm by 150 mm matrix pair
Fossil Site:
Heath Shale Formation, Bear Gulch Limestone, Fergus County, Montana
Fossil Code:
BGF705
Price: Sold
|  The
Bear Gulch Limestone is a deposit of some 70 square km in extent
and 30 m in depth that has been a source of one of the most diverse
assemblages of fossil fish with some 110 species having been
described over the past 30 years. Most were new to science, and
provided a unique view of the marine environment of Mississippian
times. Fine preservation of both fish and invertebrates is a
hallmark of these deposits, presumably due to an anoxic depositional
environment. This fine specimen is an example of an unusual fish
known as Apholodotus ossua with a narrow blade-like shape. Modern
fishes of such morphology are often inhabitants of extremely
weedy, sheltered environments. Locomotion is by undulation of
the continuous dorsal/caudal/ventral fin complex, and can be
used for both forward and backward movement. This one is believed
to have been a burrower as specimens have been found in what
are presumed to have been burrows. This one is either a juvenile
or a male based upon its size, and would make a fine addition
to any collection of Bear Gulch fish, seen here as both halves
of a part and counterpart specimen.
Also
see: Bear Gulch
Fossils Paleozoic Fish of the Bear Gulch Limestone
Reference:
Frickhinger, F. A., Fossil Atlas Fishes, 1995, p.327. |
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