Rare Metopolichas verrucosus Russian trilobite

Metopolichas verrucosus (= Metoplolichas)

Class Trilobita, Trilobite Order Lichida, Suborder Lichina, Superfamily Lichoidea, Family Lichidae

Geological Time: Lower Ordovician

Size: 70 mm

Fossil Site: St Petersburg, Russian Trilobites

Metopolichas verrucosus Coming from the nearly half billion year old Lower Ordovician Wolhovian Level deposits of the Wolchow River region near Saint Petersburg, Russia, this is truly one of the very rarest Russian trilobites, the Lichid, Metopolichas verrucosus. They are usually only seen as fragments: a pygidium, a partial cepahalon, etc. In over 15 years, this is only the SECOND the primary source of Russian trilobites has ever had found. While not as showy as its Lichid cousins of the genus Hoplolichas, it Schizochroal eyes of the Devonian Phacopid trilobite Phacops ranafar outclasses them ALL in terms of rarity. Notice the many tubercules present on the the cephalon, genal spines, and pygidium, a common trait of Order Lichida. The species name is derived from verrucose, meaning with warty excrescences; this one has them in abundance.

These images were taken some 20 years ago and have since propagated far and wide on the Internet, as well as Holochroal eye of a Platyscutellum trilobite. The facets exhibit very dense packing of small facets with a single corneal layer covering all lenses.those of Hoplolichas tricuspidatus, Hoplolichas furcifer and Hoplolichas plautini. 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 see: Russian Trilobites

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Metopolichas verrucosus  Russian Trilobite

Metopolichas verrucosus  Russian Trilobite


Courtesy: EDCOPE Enterprises