 This
Hoplolichas plautini specimen is testament to the creativity of adaptation
by means of natural selection, as well as to the art of trilobite preparators.
The spinous nature of the exoskeleton of this trilobite is a common phenotypic
trait of members of Order
Lichida (as well as Order Odontopleurida that was
formerly Lichida Superfamily Odontopleuroidea); of course, spines are
a common feature of trilobites from their earliest origins, and appear
in diverse and elaborate displays. The selective pressure for nature’s
spinous creativity was of course the  perpetual evolutionary
arms race between
predator and prey. The 100 sharp spines of this trilobite would have
been a nasty morsel to even some of the newer reef system predators of
the Ordovician seas, such as fish with jaws.
These images
were taken some 20 years ago and have since propagated far and wide on
the Internet, as well as  those
of Hoplolichas
tricuspidatus, Hoplolichas
furcifer and Metopolichas
verrucosus. It is not easy to miss the eye lenses that very
closely resemble schizochroal
eyes (with far fewer lenses than holochroal
eyes and each lens with an individual cornea) that are found exclusively
in trilobites of Order
Phacopid, Suborder Phacopina. However, the number of lenses in this
Hoplolichas are far fewer than the typical few hundred to 700 found in
Phacopina (albeit, there are some
Phacopina with greatly reduced number of lenses, apparently an
evolutionary adaptation). It is hardly unusual for the crystal lenses to
be preserved in magnificent detail in Phacopida (above right), and the
Hoplolichas eyes seen here have been manufactured accordingly. More recently
prepared Hoplolichas
sport the ostensibly correct holochroal versions with thousands of tiny
lenses, as shown above.
Also note
the near perfection of the spines. Typically in trilobite preparation,
longer and fragile spines are broken off, then reattached, yielding a
less slightly outcome. Legend has it the Russians used their space-age
technologies to extrude these as a polymer through a fine needle. On
balance, this is a magnificent trilobite rendering that does not depart
to far from reality. Also
see: Russian
Trilobites |
