WARNING!: LONG POST WITH LOTS O' WORDS! And that’s a wrap! This season has been a banner one. I can happily say that, of the 34 new species of trilobites I’ve added to my collection, 22 of them were from field collecting. I have not only added several species (breaking my 2017 record of 14 field collected ones), but a good number of them are exceptionally rare, and a few are not yet described. I’ll get to the highlight reel after this written report. Readers of this blog may remember that I’ve been plotting and planning the 2020 year throughout the late autumn of 2019 and early winter of 2020, and doing so with a close cadre of seasoned collectors. This involved digging into a lot of the ancient literature and scoping the satellite imagery. I created a working map of the province with pinpointed areas. And then it was out in the field to do the on site prospecting. No word of a lie, but 9 out of every 10 prospects were duds. That is just the way it goes, but even if one whiffs nine times, that one productive site makes it all worthwhile — for as long as the site lasts, which is generally not long. The numbers don’t lie. This has been an incredibly active season. Yes, Covid and its disruptions did mean no collecting in the US this year, and no (semi-)annual Bowmanville quarry visit. I was already prepared, pre-Covid, to focus more of my energies on Ontario as I continue to chip away at a field guide on Devonian trilobites, which is coming along and will require chasing down photos of specimens others have collected. That is steadily in the works. In total, I visited 34 distinct locations near and far. From rock piles here in London, up to Manitoulin area, the whole slim band of Ontario’s Silurian from Niagara Falls up through Tobermory, various Ordovician spots, into the province of Quebec, and just about everywhere else. My season kicked off on March 7th while there was still a bit of snow on the ground, although spring came early for the first time in years (2019 and 2018 were real laggards with shots of snow into late April). I spent 71 days in the field, in a season spanning 230+ days — again, a new record. Although there were slow months, those were made up for by spending four multi-day digs with field comrades. The season ended well into November, and although I could have squeezed out a few more field days, but there is nothing all that gainful within a 3 hour drive from here, and that would mean going on trips lasting days (or more than a week) -- time I do not have due to my day job, and the diciness of imminent winter weather. So now to open up my field notebook and do the month-by-month accounting, withholding any specific location data of course. March: Number of trips was 16, with nearly all of them very close to home in Amherstburg Fm material, and one dud visit to Ingersoll. I started off strong, which is generally the case when you’ve been cooped up over the winter and regarding the completely wide open potential for the season, buoyed up by excitement and promise, ready to apply the digital sleuthing to analog site visits to confirm or deny site viability. April: Number of trip days was 12. I added another local spot, which I quickly depleted. I also visited Formosa Reef, and came upon a new Dundee Fm spot completely by accident after some prospects in Oxford County turned up nada. It was at my Dundee Fm location that I found fragmentary examples of Coronura aspectans, as well as a new species of Odontocephalus that I initially and hastily mistook as Anchiopsis anchiops. Of that species, my local glacial drift spot gave me some very nice partials. It was also in this month I found a new surprise spot (closed for good since Spring) filled with Terataspis. May: Number of trip days was 10. There were a lot of trips to the lower Devonian spot in a public area, but which is tapped out completely. I also found my first Burtonops cristata, and a near complete and large Calymene platys. I also made a number of trips to a new London spot that is glacial drift erratics containing a big spread of Devonian rocks from Oriskany, Bois Blanc, Amherstburg, and Dundee Formations. It was there I found pieces of Terataspis, including a hypostome. The spot was exhausted pretty quickly. It was also in this month that I made my first and only trip to Arkona this year, and I don’t see much point in going back for the same old corals. I have also heard that most of the site is now posted. June: Number of field days was 7. It was one last trip to a Devonian spot, one very local trip to the Amherstburg Fm, and four days in the northern Silurian where I found virtually nothing. But the trip with the field comrade was amazing. Even if you find nothing, it is all learning as we read the rocks. Science is about falsification, so being able to confirm an area is not productive is valuable knowledge. Our dipping into the Silurian did not pay out, but we did extend our search into the Ordovician (Georgian Bay and Cobourg Fms) without too much luck. July: Number of field days was just 1. It gets a bit too hot in July, and I had pretty much exhausted my site prospect list that needed a refresh. Sometimes part of the season goes quiet, punctuated by much bigger trips. In this case, I knew August was in planning stages with field comrades to visit the Manitoulin area. My trip to a local spot on June 26 was a bust, and then it was silence until July 26 to another local spot, also a bust. But I had stuff to prep, lectures to record, and a big trip to plan. In terms of trilobites, I actually found none since June 9(!) and just a fragment on August 1. That’s a long fallow period! August: Number of field days was 13, and it involved another tour of the Silurian, this time in the southern stretch of the band. Four tiny, public sites and nothing to show for it. But, prospecting with a comrade is its own adventure and reward. By mid-August, it was the big Manitoulin area trip where I bulked up on a lot of missing trilobite species in my Ordovician collection, including a mostly complete Dolichoharpes dentoni. And then it was radio silence from August 17 to September 6. September: Number of field days was 10. As the semester began, this is actually pretty good. Seven of those field days were in the province of Quebec. Before I left for that trip, I had located another local rock pile of Devonian erratics where I found a complete and large prone Eldredgeops rana. Repeat visits have turned up nothing, suggesting I’ve exhausted that spot. Crossed off the list now. September 23 was day 200 of my season. October: Number of field days was 6. Traditionally, the October Thanksgiving weekend would see us at Penn Dixie during their post-season, but anything traditional went out the window with Covid. With our borders shut tight, trips are limited to within this province. The site where I pulled out that giant Eldredgeops rana did not yield up anything more of significance. A trip to my Amherstburg Fm material simply added more of the same trilobite fragments, but at least one more piece of the rare lichid, Echinolichas sp. A prospecting visit to a pond indicated more of the similar Dundee Fm material I encounter in Oxford County, but the lithology was slightly different and far less fissile. Speaking of Oxford County, I did return there as collecting conditions improved, and was able to find more fragments of Coronura aspectans and Odontocephalus n. sp. The only other site visit was an on spec, few hour trip to a pond that certainly had Devonian rocks, but representative of the very worst horizons of the formations present. November: Number of field days 6. Usually by this time we’re cutting it pretty close to winter and snow. Any day above five degrees without rain is a day to capitalize on. It is also a battle for daylight as the days just get shorter and shorter. Unseasonable shots of warmth do happen, though! One good aspect of November hunting is similar to that of April: much less foliage cluttering up the view. Stuff that may have been hidden by thick, leafy bushes can now be revealed. The lack of nuisance bugs is also a plus. A welcome burst of almost summer-y warmth swept through this part of the world, and this meant gathering the crew to do a trip. We did some prospecting for new locations in the North Middlesex and Lambton Shores areas, but didn’t turn up anything. Also, a visit to Oxford County was fun, but nowhere near as prosperous as previous visits. Total Locations: 34 Total Days in the Field: 81 Only four of the locations were already known/discovered last season. From a prospecting perspective, we did a lot of heavy lifting when it came to exploration. Of the thirty new prospects, only seven are sites I would consider returning to a few more times. So what does the next year’s season hold? Quite a lot, actually, but not anything I want to post publicly. There will be a continued focus on Ontario trilobites. And, if the US border opens up, maybe a trip or two down there if it is safe. In terms of trilobite species collecting here in Ontario, I was thrilled to bump into 36 of them, 17 of which were new to the collection. Most of them were fragments, but they still count. I know that one of them, and maybe two, could be new species. A few others have either never been reported in Ontario, or were reported over a hundred years ago. When it came to note-taking, I recorded every visited site with some remarks about formation(s), lithology, and fauna. I would focus on number of presented trilobite species as well as an outlook for future visits. Almost all the Ontario sites I prospected have a downward outlook, which is to say that repeated visits will result in lower yield each time, eventually approaching zero. Two of my prospected sites have either been permanently or temporarily closed, and many of the local sites near me are just plain tapped out. Still, being highly circumspect about locations is the only means by which to ensure that all our hard work isn’t simply taken advantage of by vultures and mercenaries who will empty everything out a la "rip and run" — not that many of my sites are at risk of that given their very poor outlook. I was also fortunate this year to make a lot of great contacts in the field and in research. As solitary as fossil hunting can be at times, the importance of socially networking cannot be underestimated. You just never know if the person you network with grants you exclusive access to a spot or shares a tip. I met quarry owners and museum folks, and it is great that one can collect friends and fossils along the way. I can say that the future of fossil collecting in Ontario is still fairly bleak despite some excellent opportunities in the near future. Between development, private property, land remediation, park designations, and quarries not so keen on allowing collectors and researchers in — not to mention unscrupulous operators — most of us know the heyday of collecting is largely behind us, and all there is left is tiny, easily exhausted spots. It’s a kind of struggle over the last dregs, as now going through rocks under a bridge dumped by a nearby quarry is considered a “good spot” given that in situ material is scarce or impossible to access. But I’m optimistic in a way because it just means more research, more planning, and going farther distances. It also means secrecy, sadly. I should say that there will likely always be spots to find horn corals, water-worn brachiopods that wash up on shorelines or appear in ditches. But for those of us who collect trilobites or complete crinoids, those constitute a worthwhile trip to the field. Compared to the good ol’ days when we were spoiled with lots of quarries and other sites, we now have to work ten times harder for ten times less. I started collecting seriously after those salad days, so my frame of reference is my experience with what things are like today. When some of our veteran collectors tell stories of the old days, I simply cannot imagine the incredible abundance of specimens and opportunities. But, in the end, I’m just too stubborn to give up. That being said, if a brand new serious collector wanted to start now, I’d be obliged to say, “prepare for a lot of disappointment.” This year had its share of disappointments, for sure. Many spots were just rubbish or nonexistent. I think only the most fiercely determined can do moderately well, on rare occasions, with enough persistence and diligence — which we can say is a necessary but not sufficient condition for success. I expect to fail at a rate of 10 to 1. And even in the old days it required patience and persistence. That whole availability heuristic is something many of us fall victim to. That is, we’ll walk into a museum and see marvellous specimens, or look at the sum total of a lifetime of collecting which shows only the very best. And then we erroneously think, “I could find all this, too.” We have to remember as well that only a handful of some species have ever been found in Ontario over 150 or more years. A lifetime collector may only display the 1 in 1,000+ pieces they found in the field. Barring a miracle, we may only have five to ten years left in this province for anything gainful, all of it requiring even more effort. In just the last seven years of collecting, only the last three of which I can say I got serious about this, I’ve already seen locations shutter, sites over-collected, and other spots simply vanish under the steady press of development. I’ve seen one major quarry prohibit all collecting, and another that has put ever more limits on visitors and time spent there. Other once gainful sites are now posted. All of this in just three years. There is no sign of that trend reversing. But, as options narrow, what is left is to go wide. I’ve got the hunger, the tools, and a close circle of comrades. All one really needs is a plan and determination. Sometimes you act on little more than a tip you gain from a casual conversation, and that starts up an adventure where you eat up hundreds or thousands of kilometres of road. I even acted on a tip I got from a municipal worker who said something about an abandoned quarry where she had found a few fossils, and away I went! And I should give a big shout-out to my very best collecting comrades with whom I’ve broken much rock, drank much beer, and shared many a laugh on our sprawling days-upon-days adventures. To KB, MT, and MD. I couldn’t have done this fossil season without you. Lest we forget that the very foundation and bedrock of fossil collecting is the time we spend with our comrades. I also managed to donate all my Devonian placoderm material to a museum. One of the pieces may actually appear in a new exhibit, and a few others are waiting for a placoderm specialist to study them and possibly describe a new species named after yours truly. Very exciting! Tools and Methods I got to use a rock saw again this year, which is always exciting for someone who didn’t grow up with power tools. I made two new field collecting purchases: a pair of boots that are already torn, and a tactical pack that is… also already torn. My prep lab saw two new tools in the mix: a Pferd scribe and a Vaniman blaster. I need more fossil pants as all of them have ripped knees and the arse blown out. I will also need an intermediary scribe to replace my crummy PT Aro. Possibly some equivalent of a MicroJack wouldn’t hurt. Oh, and more field gloves. Prep Bench Goodness Not too much in the way of prep this year beyond some quick things, and a lot of half-done projects. I did spend a lot of time on a Morocconites. I do have a number of specimens for winter prep, but I also want to get back at my long neglected drawing routine. Still, not entirely idle as I did get through some of my finds already… A gallery of my work this year: UPDATE: As promised, I'm continuing on with this marathon post, taking a small break from grading a zillion final papers. So, what were the "Best of 2020" finds? It's tough to pin down because it has been such a stellar year. On one hand, the criteria might be on the basis of aesthetics, and on the other it might be on account of rarity -- these do not always conveniently overlap like a Venn diagram. So, this year I'm going to go with the best finds by geologic period The Winner in the Ordovician Category goes to... Dolichoharpes dentoni! Yes, there were some other nicer looking contenders, and even a very rare echinoid, but this ventral specimen that still needs to be flipped and prepared wins by virtue of its scarcity. It is a pity that some of the shell is missing, but this one is still a highly coveted specimen for trilobite collectors. The Winner in the Devonian Category goes to... Terataspis grandis. This is just one of many large fragments, most of which are still in the process of preparation, so this is more of an example placeholder. This rare and highly coveted lichid was truly a giant of the lower Devonian seas. So none of the best included complete trilobites, but that on account of those being fairly common (but nonetheless interesting), such as the Ceraurus pleurexanthemus, Flexicalymene senaria, and Eldredgeops rana (the very inflated one I found near my house!). In terms of trilobite tally for 2020, I bumped into all of these in the field, a good number of these fragmentary. Acanthopyge contusa Anchiopsis anchiops Bathyurus (Raymondites) longispinus Bufoceraurus bispinosus Bumastoides milleri Burtonops cristata Calymene platys Calyptaulax callicephalus Ceraurinella trentonensis (?) Ceraurinus marginatus Ceraurus sp. Ceraurus pleurexanthemus Coronura aspectans Crassiproetus crassimarginatus Crassiproetus canadensis Dolichoharpes dentoni Echinolichas sp. cf. eriopis Echinolichas sp. cf. hispidus Ectenaspis homalonotoides Eldredgeops iowensis southworthi Eldredgeops rana Eomonarachus intermedius Failleana indeterminata Flexicalymene croneisi Flexicalymene granulosa Flexicalymene senaria Gabriceraurus dentatus Gravicalymene sp. Greenops widderensis Isotelus "mafritzae" Isotelus maximus Mannopyge halli Meadowtownella n. sp. Mystrocephala stummi Odontocephalus n. sp. Physemataspis pernododusus Pseudodechenella sp. Pseudogygites latimarginatus Sceptaspis lincolnensis Terataspis grandis Thaleops sp. Trypaulites calpyso Trypaulites erinus Total: 42 New: 18 That's a lot of bugs, and that does not include any I purchased or had gifted (that will be for another post). For the keen trilobite specialists out there, you may notice some eye-watering or surprising species in that list. That's what dedicated field time can yield. There are a number of species as well in that list that have never been reported in Ontario, or have been reported well over a hundred years ago. I am particularly proud of all the fragments of Echinolichas I picked up, of course, from the Appalachian basin side of the Amherstburg Formation. Even the Acanthopyge contusa fragments I always brought home in the event that there might be some scientific interest, and it pays to have a large supply of specimens to study. The giant Coronura aspectans pieces were a delightful surprise, too, as well as the nice pygidia of Trypaulites. Of the roughly 88 Ordovician trilobites of Ontario, I can say I have examples of 29. I shamefully have zero Silurian trilobites from Ontario, but I have 21 out of nearly 30 of the Devonian taxa (and hence why I'm prepared to create that field guide). Oh, and speaking of books, having everything readily available as PDFs on my field tablet is certainly helpful when I'm out and about, but there is something precious about having physical books (bibliophile that I am). I added the following to the library: * Isotalo, P. (2015) Ordovician Trilobites of SouthernOntario * Ludvigsen, R. (1979) Fossils of Ontario 1: The Trilobites * Moore, R.C. (1959) Treatise O: Arthropoda I also bought a large coffee table book of the works of my favourite paleo artist, Jay Matternes. There are a number of other books I need to track down and add to the reference library. Illustration output was very limited this year compared to last, but that was more on account of being out in the field so often. I do have a large number of trilobites in the queue for winter. This would be one of only the two illustrations I've done year, and my favourite: So, what a fabulous year it has been despite a global pandemic, and with some potential great adventures for next season! As I won't be out in the field until spring, this blog does not quite go into hibernation; it will shift to whatever I prepare, buy, or draw. Such is what we fossil fanatics do in the winter as we plot the next season the very moment the snow melts!
Readers of this blog are already familiar with my lovely finds of Terataspis fragments, all found in the early spring (and I beg forgiveness for the false match from 2019 that turned out to be Echinolichas -- certainly a face palm moment!). But I can very confidently say that I am sitting on so many Terataspis fragments it is ridiculous. I've been spending an equally ridiculous time in the prep lab on these fragments, with nothing fully complete in terms of preparation. But I am one of the select few who has chunks of Terry sitting on his dining room table -- not that this is some benchmark of anything beyond being unbearably niche! Of course, they are set in some of the most brutal matrix ever devised by depositional powers. It is variable in hardness from soft sandy shale to the hardest crystalline quartz that requires very slow scribing and even the use of aluminum oxide. I have a few choice pieces entrusted to a seasoned preparator, but I still have tons of material on hand to get through on my own, the so-called B-pile frags. So, let's get to talking about Terry. Here are some classic images of the cranidia, which includes the three glabellar lobes. All of the lobes have fine tubercles, but it is the median lobe that has the "moon rock" appearance. It is by far one of the more impressive and diagnostic features of this monotypic genus. The first image is a rendering in the classic Hall & Clarke plates,, and the second is a photograph of a specimen that was included in Ludvigsen's 1979 "green bible" of Ontario trilobites. Terataspis has undergone some... cosmetic changes... over time on the basis of found fragments. It would not be until Riemann in 1941 that we more accurately approach the proper morphology of the trilobite. In the first incarnation of reconstruction, the cranidia and the pygidium is largely correct, but there was a mishap in attributing a large dalmanitid to account for being included for the pleurae, which doesn't quite lend it the right look. Only with more fragments found properly attributed could a more fulsome and accurate reconstruction come to the fore. I'm not even going to ask about the bizarre prong-spines along the axis! It should be noted that large organisms such as these will vary significantly in terms of their prosopon and other morphological features; some will have additional tubercles, spines, and even spinose protrusions not seen on other specimens. That is a feature, not a "bug" (ok, the pun was uncalled for!), just as any complex organisms will show different phenotypic variations (think of Homo sapiens and our rich diversity as an example of how we simply don't look identical). But let's move on to some of my own examples. It certainly doesn't get more diagnostic than this. This is the left librigena, sadly missing some shell from having been exposed, and fairly flat in being preserved in a layer that is largely arenaceous and weathered. But already, the fragment is 13+ cm long, and it isn't even complete (complete cheek might be pushing over 15 cm -- that's shy of just half a foot!). The fractal-like spines appear here. Gimme some skin! This material is "perversely tough" to quote Ludvigsen. You do not split this material because it is 70-90% chert by volume in Bois Blanc Formation, dominated by coral, riddled with crinoids and other fauna. These fragments occurred in the tough micritic horizon where one may be fortunate (as I have been) to find full prone Calymene platys, but the shell is rarely going to separate from the impression. But once you find telltale signs of Terataspis, you begin to find them everywhere. At my secret location, I was able to bucket a good number! Here are some in situ pictures of what the material in the field looks like. Very underwhelming! But keep in mind that this is only what is visible, with the rest encased in tough matrix. The inexperienced collector would likely not bother with these, thinking they are just tiny fragments. An example of what lurks beneath. I am far from done with this piece, but this is likely a piece of the pygidial spine, ventally oriented. Another piece that might have been overlooked, I had already put a good innings on the cranidium of this specimen before handing it off to a seasoned preparator. I now have better tools and can manage my own workload. The left cheek will sadly not be there, but the right one might be... as well as the occipital ring... and who knows what else? The median glabella is about the size of a golfball. The initial field state only showed a few tubercles. And even close to home! These two pieces are positive/negative of each other, part of four distinct pieces I found from glacial erratics here in London. From the same glacial drift, a thumbprint-sized hypostome. Lichid hypostomes are not known for their fanciness compared to, say, Hypodicranotus. But here is a Terry hypostome I still need to prep. From the field to the lab of my comrade, a ventral portion of the pygidium (sans spines). A chunk of thorax. I'm far from done with it, but it looks... crappy in the field. A bit of scribing and dolomite abrasion, and we're seeing a wee bit more. But if we look closely... Spines... on the pleurae. These are not the end-of-pleurae spiny frills, but appearing before the tips of the pleurae. That variation I find exciting! A left genal that is not yet completed by my master preparator and comrade. I have a few free cheeks lying around, moulty buggers! Another work in progress. We have two apparent pygidial spines, but there is other specimens in the mix (see the occipital ring above, and there is a free cheek at the far right (I've since exposed that but not taken a photo yet). Moulting ground! (Or tidal sorting). Like night and day. This chunk of cranidium took me 60+ hours, including going the nuclear option of using aluminum oxide on hard, crystalline chert that dolomite was too soft to touch. Those spinose tubers "fly" over the very deep furrow (4 cm) above the occipital groove. The median glabella already measures about two inches across and long. Sadly, it is crushed, and the anterior edge has a chert separation between the tubercles and the base. Not much more I can do with this piece, and sad other parts are missing. But here is a gallery of other shots, including texture (please pardon the dust!). These photos are rubbish since they do not convey the full depth and detail of having it in hand. There is more I could do with it, and I could spin a yarn of so much that was done to ensure it could get to this state. But this was great practice for the tons of material I still have left, with the possibility of some surprises. Obviously I have no photographed and shown every piece I've collected. I've just been picking at the smaller, easier stuff -- there are bigger specimens in the mix with some hope that they might be complete.
I've not been out in the field much in the last bit, but that is something I will be rectifying shortly. I've actually been getting a head start on a big backlog of prep projects. I've put in about 120 hours of lab time, with about half of that involving specimens that I am not ready to show yet, but which may turn out to be very exciting. like, "knock your socks off" exciting. For now, more show and less tell! This common Flexicalymene senaria from the Neuville Fm of Quebec was lodged sideways into the bedding plane. This one took a bit more effort because, like most Neuville material, the first few millimetres are easy-breezy shale, and then you hit very hard limestone that even dolomite at higher pressures struggles with. There is still a bit of matrix stuck here and there, but there are also three major cracks running through the trilobite, so it is by the miracle of matrix that this holds together. It has a lot of compression damage on account of its orientation. Apart from the unfortunate ding on one of the axial rings due to exposure, this turned out okay. Much of this bug was set in a hard, calcitic crust where dolomite tends to polish rather than abrade. But I soldiered through it. The right eye is a bit busted, so I didn't continue abrading that any further. I spent some time organizing the chaos of many, many flats of rocks, and came upon various prep projects I either abandoned or forgot about for one reason or another. This Penn Dixie bug was consigned to "B-grade" status on account of its compression damage. I don't seem to have a "before" photo of this one, but I recall it was listing on its side. Notably, as I took this one up again, I removed every little grain of matrix from this one, apart from where it is crushed (right eye and anterior margin of the left cephalon). Sometimes you have to leave a bit of the crud on as that is the only thing keeping it from breaking apart! It certainly has character, and can sit in the display case as a partially pedestaled piece. And now on to a recent arrival in the Postal Formation... Not the very best of preps, but I got this for a sweet price. This is a Walliserops trifurcatus from the Devonian of Morocco. It differs from W. hammi in having a very long trident. It is one of the more enigmatic trilobites insofar as there is no clear consensus as to what purpose and function the long trident served. Competing theories suggest camouflage, sensory apparatus, competitive sexual selection (akin to stag beetles), or simply a means of levering off the sea bed. With no access to observational behaviour or DNA, we likely will never know. But we do know it must have served a key purpose as nature abides by the conservation of energy, and having to regrow this ornament in the course of 30 moultings would take a lot of energy for it to be simply decorative!
And that is all for now. I do have a Russian lichid on the way, and I'm occupied working on some exciting fragments (yes, fragments!) that I hope to show in the near future. The season is just about over, save for one last hurrah, but it has been my very best. I've spent a good number of days taking advantage of the welcome and unseasonable warm and sunny days by getting out in the field, collecting with good comrades. I can't say we found much of anything worth posting, but the camaraderie and doing the real work of reconnaissance is all part of this passion. It was an incredible time involving a lot of very unique events, gorgeous late fall scenery, rough terrain, old farmers, exotic radishes, laughter, and mud. I am hoping to check on a few more spots while the weather lasts, but there will not be any exciting big trips for what remains of 2020. Any of my trips that run out the clock will be local, and mostly prospecting work. I did acquire some lovely new bugs. A lovely example of this species, this is a fairly above average in size Odontocephalus aegeria. This was found and prepared by a very renowned trilobite collector, and measures 90 mm. I've been more drawn to the synphorinae this year given the excitement of finding a potentially new species of this genus in a relatively local spot. The purpose of the cephalic denticles is not entirely known with certainty, but it is an intriguing piece of morphological ornament that many of the synphorinae share. The Illinois classic, Gravicalymene celebra (or some people call them Sthenocalymene). These always come out as steinkerns, and they are harder to come by these days. Although I already have a tiny pair of these, the inflation, size, and detail made this a very worthy addition to the displayable collection. The calymenid body plan doesn't change all that much, being fairly consistent through the Ordovician, Silurian, and early Devonian. The Silurian calymenids (of which this one belongs) seemed to reduced their size from some of the very large ones in the Ordovician (think here of Flexicalymene ouzregui, Colpocoryphe roualti, or Nesereutus tristani), but then reverted to large sizes again in their last hurrah in the early Devonian (Calymene platys). This is not to say that there weren't smaller Ordovician species on par with their Silurian descendants when we consider Flexicalymene senaria, Flexicalymene croneisi, Gravicalymene sp.). Most Gravis need a bit of a taxonomic clean-up. Usually one of the distinguishing characteristics of the different genera is the presence/absence and shape of the cephalic protrusion.
There are more bugs coming soon, but maybe I can hit paydirt at one of my local sites. As long as the weather holds, I may as well make the best of it! |
Kane Faucher
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