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RARE - FINEST DISPLAY BELEMNITES
IN MATRIX WITH AMMONITES
- Drugendorf, Germany
UPPER JURASSIC PERIOD
(MALM): 154 - 144 million years ago
The first thought that
came through our minds when we acquired this specimen was - 'AMAZING!'
You couldn't ask for a better geometry and arrangement in the large host
rock to better display the highest quality belemnites than this piece
presents. The original host rock displays two beautiful three-dimensional and solidly
mineralized Hibolites hastatus belemnites attached to their
original host rock as found. To accompany their journey, they rest
amidst a sea of fellow cephalopods in the form of naturally orange
ammonite impressions. What a beautiful sight it must have been to
behold dense swarms of these ammonites and belemnites darting through
the Jurassic seas 150 million years ago! Arrangement of the
belemnites is original as they were found and possess remarkable natural
color variations. Matrix stands on its own and shows the fossils
from multiple directions.
BELEMNITES
are extinct straight-shell members of the Cephalopoda that died out at
the end of the Cretaceous along with ammonites and dinosaurs.
The
term 'straight' cephalopods is used here to describe fossil examples of
straight ammonoids called Baculites, straight nautiloids called
Orthoceras and Belemnites.
Cephalopods
evolved during the Late Cambrian Period. Their bodies were
predominantly elongate with conical shells. Some of these
creatures evolved into semi-coiled forms eventually giving rise to
coiled cephalopods like ammonites and nautili. Another branch of
straight-shelled cephalopods continued to coexist with the coiled forms
on into the Pennsylvanian Period. These straight forms were much
less diverse and abundant than the coiled cephalopods, as a
whole. Straight
cephalopods were among the most advanced invertebrates of their time having
eyes, jaws, and a sophisticated nervous system. These creatures
were predators that swam freely using a
jet propulsion system by squirting water from their bodies. They had
tentacles and ink sacs also much like the present-day squid.
Except
for belemnites, cephalopods
had
external shells with hollow internal chambers separated by walls called septa. A tube called the siphuncle, connected the body with the
chambers allowing the animal to fill them with water or air, changing
its buoyancy in order to rise or drop in the ocean.
Only
the last and largest chamber was occupied by the living animal.
Belemnites
were different than
other straight cephalopods like Orthoceras in that they had internal
shells called 'guards' which were covered with the soft, muscular
tissues of their bodies. These shells were also chambered but much
less complex than the straight varieties of nautiloids and ammonoids.
The gas chamber by which the animal regulated its buoyancy is called the
phragmocone. In finely preserved specimens, it is a conical,
thin-walled opening at the posterior of the shell. Rare belemnite fossils complete with soft body parts
have been found and provide us with a
valuable glimpse of what these creatures looked like when alive.
Belemnites possessed 10 tentacles and males had chitonous hooks which they
used to grasp the females during mating.
Straight
cephalopods probably lived for one to six years, with the majority living two to
four years. They fed on plankton (tiny free-floating organisms), sea
lilies, and smaller
orthoceras. Although many fed off the ocean floor, others may have
caught plankton while floating or swimming via jet propulsion,
expelling water through a funnel-like opening to propel themselves in
the opposite direction.
Because
straight cephalopods lived
exclusively in marine environments, their presence also indicates the
location of prehistoric seas.
If
you appreciate fossil specimens that are rarely seen on the market, then
this example should appeal to you. The site where this fossil was collected is
unique with no commercial production. A finely preserved and
excellent display specimen of these once-prolific creatures of the
ancient seas.
FINEST, MOST IMPRESSIVE EXAMPLE WE'VE
HANDLED - WORTHY OF PUBLIC DISPLAY!!!
LARGE MATRIX SHOWCASING HIGHEST GRADE
BELEMNITES & ORANGE AMMONITE IMPRESSIONS!
6.75" x
5.75 overall
with matrix, belemnites are 3.2" and 2" long
SOLD
BEL-003
Actual
Item - One Only
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