They're bumpy, spiny, and ugly... And they are my absolute favourite of the trilobite orders. They are also fairly rare to find, and even digging in the postal formation means paying top dollar for what amounts to an expensive taste in trilobites! Many lichids have a great deal of very developed microsculpture, with spines and tubercles likely an evolutionary trait designed to deter predators. They were particularly successful, ranging from the mid-Cambrian to the upper edge of the Devonian. Perhaps the very best researcher on lichids would be Thomas Holloway. His work on the phylogeny of this Order is worth the read. Lichids have many classic and coveted members, including Arctinurus boltoni, the "emperor of the Silurian seas." Some of them were bona fide giants, such as Terataspis grandis, which is the third largest trilobite ever recorded. Pictured here is just one of many fragments of Terry that I have found. Although localities in Morocco and Russia have some very impressive lichids, Canada is near the top of the list as well. In our Ordovician deposits, we can count Hemiarges and Amphilichas among our crew. In the Devonian, we can add Echinolichas, Acanthopyge, Ceratolichas, and of course the great Terataspis. If we only had more outcrops of the recessive Rochester shale of the Silurian, Arctinurus would be popping up more often! And there is no doubt that we still have some undiscovered lichids in our arctic, too. I've been fortunate to find most of Canada's lichids, albeit as fragments (and I probably have more Terataspis fragments than any museum on the planet!). The early days of lichids in the Cambrian were fairly modest in terms of how dramatic they became. If we consider Damesella with its fine granulations, it more resembles a cheirurid than a lichid. An illustration of one I did last year: So let's compare to the great Terataspis. This reconstruction line drawing will need some revision, and that will happen once I have all my pieces prepared. Included here is an Arctinurus that I think is at the ROM. Despite the very dramatic surface features, their hypostomes are surprisingly dull. I have collected nearly all the Devonian lichid hypostomes in Ontario, and they are nowhere near as defined and eye-popping as an asaphid's. Pictured here is a Terataspis hypostome I found in some glacial till. Pretty unremarkable!
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Kane Faucher
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February 2024
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