Having just finished teaching a week-long course, and with no work currently penciled in the schedule until late June (although that could change), I can dedicate some serious time to fossils. This means collecting, prepping, and drawing. CollectingI'll be prospecting some new possible sites. Once a site has been picked over, tapped out, or shuttered, it's time to do the work of exploration and field survey. That means extending the search and testing the layers (or the heavy work of exposing them). Once that is done, an assessment is made as to the site's productive life-span: is it something that will last several seasons, or something an individual can clear out in a few trips? Apart from that, I got word that we are a go for a June engagement at one of the last quarries that still lets collectors in, so I'll have that to look forward to. PreparationIt's also time to get some prep done. First up is this 80 mm asaphid, but there are a bundle of Penn Dixie bugs to work on as well. This is where it stands after about six hours. Apart from some sticky calcite on the right cheek, this has been a delight to work on, but having the ME-9100 makes matrix removal much easier. In fact, since I'm waiting for a replacement stylus for my Aro scribe, I did all of this with the ME-9100, and it is great that I can dial down the BPM when I get close to the shell. There's still some work to do, such as removing matrix between a few segments and the base matrix smoothing, but I'm awaiting some scalpels in the mail to do the inter-segment and touch-up work. As an expert Russian preparator told me, never use abrasion: it burns and lightens the skin no matter what medium or PSI; it must be done by hand. That was my error on the last Asaphus lepidurus I prepped. DrawingI was far too busy and tired this week to put pencil to paper, but I have two WIPs, a few sketched concepts, and Deb bought me some black paper so that I can try out drawing white pencil on black background. At this point, I'm pretty much looking at a 20 hour backlog of bugs to doodle. Update: Managed to get three since Friday. The last bit is some tidying up of the trilobite catalogue. I recently acquired this piece, which is a Cambrian Hamatolenus sp. from Morocco.
This post is more a stub, and I'll update it when I've rolled up my sleeves for some of the stuff I mentioned above. Snow-free until January 10, and then it clobbered us. More time spent indoors and thinking that it will take a while for this snow accumulation to melt and get the collecting season back into gear. So that leaves prep and postal formation. This is a return engagement with a bug I started a few months ago. It is a giant for the location (Penn Dixie) that measures over 45 mm from genal to folded over genal. What is not shown in this image is the folded over/under side that took a ridiculous number of hours. I also took the time to level and smooth the matrix -- something I am learning to get better at, and which also takes a lot of time and patience. A very lovely full prone Scabriscutellum furciferum from Morocco. The seller was also kind to add an unexpected brachiopod surprise to perk the package. My 100th trilobite species! Asaphellus fezouataensis from a really nice seller who also threw in a little enrolled phacopid. Still trying to relearn my old drawing skills that have been neglected for nearly 20 years, a pencil rendering of an Isotelus. A Greenops widderensis... And an Eldredgeops rana with all the crush/distortion flaws.
So, for now, that's about it. I'm somewhat running out of trilobites to prep, and only expecting one or two bugs in the mail. I really hope winter won't be too long! The snow has finally buried us after an unseasonably warmer and snow-free stretch. So that means more time spent in prep, and some hunting relegated to the postal formation. This short post is a quick update on newer additions to the trilobite horde. New acquisition, the blind phacopid Ductina vietnamica. This genus was quite widespread, appearing in different faunal provinces. These regularly come up for sale, but most of them are preserved quite poorly. This one is a much better example of the species. A semi-enrolled Paralejurus spatuliformis from Morocco. This one differs from other members of the genus on account of having a, well, spatulate kind of pygidium. This one has no colour enhancements, so appears "in the buff" without having been buffed with shoe polish or some other additive to make them uniformly black. The closeup is of the holochroal eye with its tightly packed lenses that appear, from a distance, to be entirely smooth. While going through some boxes of old finds and turfing junk, I split a small and thin piece of Verulam Formation (Brechin, Ontario) to encounter this cephalon fragment of the rare lichid, Amphilichas ottawaensis. I haven't heard of anyone in my collecting circle who has spent a lot of time in Brechin find more than fragments. I had found a ventral pygidium fragment a few years ago, but nothing else... And now that the site has been shuttered to collectors, there's not much hope in the immediate future of finding more. The picture below is of a complete Amphilichas halli -- not the same species, but it gives a sense of the body plan and where my fragment fits: And that is likely all that is fit to digitally print this week. The fragment was the big surprise find while the snows are blowing and the temperatures nosedive.
Made a trip to the post office to pick up a backlog of packages that couldn't be delivered at the door, and it was a lovely little bonanza of bugs. Although a bit beat-up and sticky, this will be added to my winter preparation queue. This Ordovician corynexochid is Illaenus sinuatus, a new species for the collection. The cephalons on these kinds of burrowing bugs tend to be fairly robust, so there is considerable matrix to be removed. I'll post the complete results once I get this in the lab. - Another Ordovician trilobite, the phacopid Pliomera fischeri, from Kinnekulle, Sweden. Trilobites from the Swedish part of Baltoscandia do not tend to preserve as well, and can come out fairly weathered. From Haellekis, Sweden, an enrolled Ordovician phacopid, Nileus armadillo. Although I already have two other examples of this species, a small and enrolled Asaphus kowalewskii will nicely complement the Russian asaphid display. Top prize for this bug bonanza would go to this lower Devonian Moroccan phacopid, Wenndorfia planus. Nicely enrolled, and uniquely prepared in a tilted pedestaled fashion to show off its "assets," this trilobite was reassigned by Sandford (2005) to Wenndorfia from the species Parahomalanotus... which in itself was possibly mistakenly elevated to genus status. For those interested in some of the twitchy taxonomic tango see:
Sandford, A.C. (2005) Homalonotid trilobites from the Silurian and Lower Devonian of south-eastern Australia and New Zealand (Arthropoda: Trilobita: Homalonotidae). Memoirs of the National Museum Victoria, 62(1):1-66 Basse, M., & Franke, C. (2006) Marine Faunen aus dem frühen Unteremsium (Unterdevon) des Givonne-Oesling-Antiklinoriums (Luxemburg). Ferrantia, 46:7-41 Chatterton, B.D.E., Fortey, R.A., Brett, K.D., Gibb, S.L, & McKellar, R.C. (2006) Trilobites from the upper Lower to Middle Devonian Timrhanrhart Formation, Jbel Gara et Zguilma, southern Morocco. Palaeontographica Canadiana, 25:1-177 A number of trilobites came in the mail, with several more waiting at the post office and some in transit. First up is a Paralejurus dormitzeri This fairly common Devonian corynexochid from Morocco does appear fairly often for sale, but a lot of them are the victims of quick and brutal preparation. This one has very good quality preparation, with some minor restoration on the lower right pygidium. Finely detailed with the eye lenses, terraced growth lines, and pedestaled to show the cephalic doublure. Only a few scribe dings, and measures close to 80 mm. A cute and small Asaphus kowalewskii. Although I already have an example of one (semi-prone), this young holaspid stage specimen was too adorable to pass up. Some slight compaction between the third and fourth axial ring, but virtually no restoration of this stubby-eyed example of the species. Hooray! Another winter prep project to keep from going bonkers from fossil hunting withdrawal. This is a relatively small semi-prone Asaphus lepidurus.
Until tomorrow when a few more trilobites join the collection... This may bring my winter asaphid purchases to their conclusion for the season as it is time to collect from more than just the postal formation! And I may as well end it with a proverbial bang. This whopper of a bug is Asaphus raniceps, clocking in at about 100mm. You can make out some minor restoration, which is fairly standard. . This googly-eyed monster is the intermediate species between Asaphus punctatus and A. kowalewskii: Asaphus intermedius. Okay, not the most creative and inspired example of binomial nomenclature, but it underlines the point that this is indeed an intermediate species. These sky-high peduncles were a response to increasing turbidity in the Iapetus Ocean. Their entire bodies would be buried in the sediment with only the eyes showing - ideal for hiding and predation. This is a rubbish shot and arrangement, but I'll be organizing this properly later. I just wanted to show off the collection of these Russian googly-eyed asaphids. Absolutely beautiful, and I am quite proud of how I managed to collect so many... Although they were not cheap!
Today I received a few packages in the mail, including one Czech trilobite and five Russian ones. Here, four asaphids and a corynexochid are gathered around a trio of ptychoparids. A reflective moment for these Ordovician trilobites with the much older Cambrian trio in the centre. This is Ellipsocephalus hoffi from Jince in the Czech Republic, Cambrian in age. This is a nice assemblage. These are what are known as blind trilobites as, well, they have no eyes! . Illaenus sp. (?oblongata), a Russian corynexochid from the Ordovician. Readers of this blog might recall when I was preparing an Asaphus lepidurus not long ago. This is what a full, professionally prepped one looks like. Here is the same specimen on its ventral side, showing off a very nice hypostome! This is definitely "wide-load" - Asaphus latus. Almost as wide as it is long. The aptly named Delphasaphus delphinus fully prone and looking a bit like a dolphin... if a dolphin were a segmented arthropod from over 400 million years ago. This is the biggest of today's acquisitions at over 76 mm: Asaphus holmi. Below is the ventral side showing its hypostome:
I received my newest batch of Russian asaphids today, and all credit due to Mikhail for his preparation skills. These are large and perfectly prepared trilobites, a welcome addition to my growing collection. So the trio I got today. On the top is an Asaphus lepidurus for me to prep. On the left is an Asaphus expansus gracilis. On the right is the aptly named robust Asaphus robustus. Wow. The pictures hardly do these justice, but I will be re-shooting images for the trilobite gallery soon. A. robustus A. expansus gracilis.
Despite some flirtation with the freezing mark the past few days that is looking to put my Friday trip to Arkona on hold, on the whole spring is definitely showing itself. This one is just a short post to highlight some river finds, and show off my newest Russian asaphid. UPDATE: actually, two. NEAR: On Monday I went back to the river on campus, remembering this time to bring my trusty rock hammer. There was not much to be had among the dull, plain, river-worn rock and the plentiful limestone only filled with tiny shell hash, but closer to the end of my time there before having to teach, I pulled out these odd beasts. Once I got confirmation of what they were, and that they are somewhat rare, I went back to collect the rest the next morning. So what are they? I've seen these before and just dismissed them as some kind of wacky brachiopod. Not so! They are somewhat related to bivalves but occupy a place all their own as being rostroconches. These planktic, valved creatures would more resemble a taco than a clam. Their hinges are somewhat weak, and they have a long rostrum (the piece on the far left, centre shows it best - the striations that appear like someone scraped it). Looking at the comparable species in the general strata, it may be a Conocardium cuneus. It is a first for me ... at least the first time I've kept one. It was interesting to learn that finding these is far from common, and yet I pulled all of this from a single rock. FAR: This is another lovely Russian asaphid, the fifth that has arrived in my collection, and with five more to come. This would be a nice, prone Asaphus plautini from the Mid-Ordovician, Aseri Stage, collected from the Gostilitsy Quarry near St Petersburg, Russia. It is about 62 mm long, so about average for this species. Here is the evolutionary sequence chart from thefossilmuseum.net: But wait, there's more! Today I welcome species #6 to the family, Asaphus kotlukovi:
I have a soft spot for large asaphids (who doesn't? LOL), and the ones that occur in the Aseri Formation in St Petersburg, Russia are quite stunning for their size and apparent simplicity, if not their variation. As time went on, and with more turbid seas, these asaphids started developing longer eye stalks, or peduncles, so that they could - like modern day crabs - keep themselves buried while only their eyes would be above the sediment on the look-out for predators or prey. I recently purchased a Asaphus kowalewskii a few months ago, which also represents pretty much the extent of eye stalk development. (Photo credit: http://www.fossilmuseum.net/Fossil_Sites/trilobites-russia/rissian-asaphida-trilobite-evolutionary-sequences.htm) -- Above you can see the evolutionary progression of the Russian asaphids. Arriving in the mail today were two more to add to the family: This enrolled specimen is Asaphus cornutus. The rolled up appearance gives it a kind of "Kermit" like look. My forum friend Roger has an Isotelus gigas (also a related Ordovician asaphid) that he nicknames Kermit. And this lovely and large prone is Asaphus punctatus. I'm pretty happy with these two new trilobites.
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Kane Faucher
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February 2024
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