Recently returned from a three-day dig in New York. Despite all the lovely weather leading up to the trip, an almost wintry weather system was working its way through this part of the world with a lot of cold and precipitation. Not exactly pleasant collecting conditions!
Day 1: Penn Dixie
The excavator had been busy the days leading up to our visit. 160 fresh new piles of Windom shale were dug up and off limits until the annual Dig with the Experts event in May. The excavator did dig up one promising area. One of my field comrades had already visited the day before to start a bench and was finding some good material.
Friday was brutal. We only managed to stay out for three hours given the pouring rain, sleet, and the lake wind. In fact, it was so cold and wet that I didn't really take any site or collector pics.
Despite digging for only three hours, we still managed to find examples of just about every trilobite species reported at the site, missing only Pseudochenella. The two above are Bellacartwrightia sp., Eldredgeops rana, and the bottom two are Greenops barberi and Dipleura dekayi. The Dipleura is exceedingly rare at Penn Dixie, and was found in the Bayview bed.
Day 2: Deep Springs Road
Now an annual tradition, Fossil Forum members congregate at a spot in central New York, a shale outcrop on Deep Springs Road. It was snowing for a bit. Deb sat this one out, but went to Penn Dixie later in the day to find some trilobites.
As I had already hoovered up most of the usual fauna from this site last year with representatives of most of the brachs and bivalves, my sole goal was to find a complete Dipleura dekayi. Sadly, my efforts were for naught after six hours of slabbing and splitting. Most other stuff I found I gave away to other collectors there.
I did find these two phyllocarid carapaces (Rhinocaris columbina) that I gifted to my good friend Tim who had also found an amazing phyllocarid telson.
I didn't do so well on the trilobite front. It was mostly partials for me.
One of the other traditions of this meet-up is that we exchange fossil gifts. Pictured above on the left is a chunk of dinosaur jaw from Tony that could be Triceratops or Edmontosaurus. Top right are two Elrathia kingii from James who just came back from Utah, as well as some belemnites and a gastropod from Jeffrey's giveaway box. For my part I offloaded two bins of fossils to Tony for his museum. At the bottom is a fantastic gift from Tim: a Dipleura dekayi hypostome (very uncommon!) and Piochaspis sellata from the Pioche shales of Nevada.
To my good friend Tim who is a fish fossil fan, my only non-trilobite drawing. Knightia eocaena.
Day 3: Penn Dixie Again
Initially, Jay and I had plans to collect a few hours in Dunkirk where it is rumoured that Dunkleosteus pieces could be found, and a generous offer to go through some Linton coal in search of Pennsylvanian aged fish and amphibians. Things didn't work out that way, and I was kind of itching to find more trilobites at the first spot we were working on the Friday. This time, the dig was not curtailed by weather: it finally got warm and sunny. I spent 12 hours hammering and slabbing.
This is the only site pic I took, and this is a "before" image at 7 am. The chunks of rock in the foreground need to be broken down, and the area around my bucket and pry bar is the bench. By 7 pm, all of that area was cleared out.
As the day progressed, the trilobites were thinning out. I made my last significant find around 3 pm, after which it was mostly coral/brach assemblages in very tough, trashy matrix that would shatter rather than split.
Not much to write home about. This is actually a small haul compared to my usual 50-100 bugs per trip, but the pulse was pinching out and the site's excavated areas may not be ideal for trilobites this year. Still, some interesting pieces to prep.
And speaking of which, I've already thrown one into the lab to give my new tools something gainful to do. The initial field state was only showing the thorax. I used the ME-9100 to remove a lot of the excess rock, the Aro for detailing around the bug, the Paasche for abrasion, and decided to pedestal this. Matrix work was mostly filing and sanding. This kind of matrix preparation is not everyone's cup of tea, but these are common bugs and I wanted to play around with some presentation experiments.
And that's it. Not sure where/when the next trip will be given the sad shrinking of viable or accessible sites in Ontario. But I'll find a way...
Amidst teaching and grading, I am spending some time at the prep bench. Deb got me an early xmas present: a much-needed shop vac as the fine dolomite dust covering everything in the basement is a sign that it is also coating our lungs! I'll be hooking up that bad boy this week.
After the recent Bowmanville trip (post here), prep has begun on a few pieces while leaving much of it for winter. I've also been voraciously reading several trilobite papers as of late during my long bus commute. But this post is more of an odds and ends one.
Kicking it off would be ongoing work on my Isotelus (likely I. "mafritzae" morph type "B"):
The going is slow when the rock is dense, and the bug is flaky. During a quick exploratory abrasion, I had that heart-stopping moment of a piece flying off and miraculously located it in the dusty, bit-strewn blast box (that I can now clean out with the new shop vac!). It was some cuticle from the occipital ring that I glued back on. The eye is intact, and I suspect the other one will be as well. This one is tucked into the plane on an angle, so that means a lot of long scribe work to bring it down. Nothing can be easy! In this case, it will be worth it, as it is only missing a few tiny pieces from natural weathering, and already seems to measure 90 mm.
A few weeks ago, my fossil comrade from Texas, Kris, sent me hot peppers he grew and dried. We are both hot-heads and love our super hot peppers. This nice selection includes the famous Trinidad moruga scorpion that taps out at over 1.2 million Scoville Heat Units (that is about 3-10 times hotter than a habanero). I am keeping a few in the freezer to seed and plant next year, and the rest were turned into hot sauce. The process is fairly simple: sterilize the jar in boiling water, reconstitute the dried peppers in boiling hot water for 15 minutes or so, cut off the stems, add vinegar and salt, puree in a small blender. But this is a fossil blog, not "Kane's Kitchen"!
Kris perked the package with some fossils! Here are some ammonites and a reptile vertebrae from the upper Cretaceous.
Some really neat fish and shark verts, as well as a shark coprolite -- also all from the upper Cretaceous.
A very cool pyrite piece showing the cubic crystallization state, and exceptionally well preserved and detailed leaves from the Eocene.
Those leaves truly deserve their own photo. In the interim, I've been putting a very Canadian package together to send his way.
I really hope to get out to collect one more time this year, likely to Arkona. That will depend on weather, opportunity, and the healing progress of an ankle I sprained pretty badly. If not, then I suspect the next few posts will be detailing preparation progress and a round-up on a year that has been hit and miss.
DAY 1: Penn Dixie
Returned Monday evening from four fabulous days swinging hammers, slabbing and splitting in the field. We managed to hit two sites, with plans for a third site falling through due to weather and site conditions.
We left home on the Friday morning to arrive at Penn Dixie, in Hamburg/Blasdell NY (south of Buffalo) by noon time. It was not a public collecting day at the site, but members of the Hamburg Natural History Society are permitted to enter the site.
A group of us digging through some fresh material
Of particular note was just how much PD had changed since last season, and that is due almost entirely to some well-directed excavations at some key spots to reveal more of the Smokes Creek trilobite layer, but also opening up other on-site locations such as the Bayview brach layer and the North Evans limestone. We had the excavator on site for the second day, with the previous day ripping up a new spot in preparation for the annual Dig with the Experts event. We did not touch those piles, and focused on other spots.
I found this piece of Devonian wood, and it is a fairly healthy size for this location.
One of the excavated spots we spent the most time working on was fairly thin on trilobites, which suggests that they appear in deposition pulses on the seabed. There's no way knowing in advance if there will be a lot of trilobites, and so you hope to hit paydirt by attacking the Smokes Creek layer.
A fairly large Goniatite, sadly all busted up.
Later in the day, we migrated to a new gully area where some of our other collectors on the Sunday previous had found a few examples of the rare Bellacartwrightia whiteleyi trilobite. Sadly, that lead dried up and no Bellas were found. For the most part, trilobites were mostly appearing as disarticulated bits and moults, with not much in the way of assemblages or complete prones and rollers.
Full prone, but containing shell on both sides of the rock. This will need to be glued together and prepared.
I did have some luck despite the parsimonious nature of the slabs we were splitting. However, the "trilo-bonanza" was still eluding us all. A little before sunset we decided to leave and check in to our motel, grab some pub food, and rest up for day 2 of our trip.
DAY 2: Deep Springs Road
At around 6 am the next morning, our friend Jay picked us up at the motel to begin our first ever trip to Deep Springs Road in Central NY (Madison Cty). DSR, as it is known, has a shale outcrop that rests at the farthest edge of the Windom Formation, but the fauna is quite different than what is found at Penn Dixie. For example, instead of bountiful Eldredgeops rana, they are much rarer here, and in their place are more Greenops sp. and Dipleura dekayi. Also, the real stunner is the enormous diversity of bivalves and brachiopods. It is also quite abundant in Devonian plant pieces, larger cephalopods, phyllocarids, and other goodies.
Our crew gearing up to work.
We arrived just after 10 am, having gone through the scenic rolling hills and farmlands of Central NY. We were greeted at the site by so many of our Fossil Forum friends, some of whom I got to meet in person for the first time. There was no shortage of fun-loving personalities here, and the amount of camaraderie, sharing, and helpfulness was exceptional.
Jay and me ready to start wrecking it all up to do some serious landscaping.
Within five minutes, I was ready to get to it. In the picture above, that wall behind me would be the first to be ripped out to generate a lot of slabs for splitting. By the end of the day, I would have cleared an area 2 m x 2m x 1.25 m.
This slab simply has to go, 150-200kg or not.
Unlocking fresh stuff requires some slabbing, something I tend to enjoy doing. After some overburden was cleared, it was time to maneuver this one off the ledge. As can be seen above,. the rock is heavier than me as I sit on the pinch-point bar which was bending. Eventually, I was able to work from the left wall, wrestling it out, and driving it with my boots down the hill for others to split.
Group shot. From left to right: Dave, Jay, me, Mike, Tim, Dave 2, Jeffrey, and Leila (who fed us scrumptious homemade cookies).
The weather had been promising to make this trip a real bust, but fortunately we only had some intermittent drizzle, with the rest of the time being clear and not too hot. Everyone came away with lots of interesting finds, and friendships were formed or strengthened in breaking rock together.
Bivalves and gastropods. I'm not really up on the taxa, but these are fairly typical finds for this site.
More neatly ridged bivalves.
Large spiriferid brachiopods are fairly abundant at DSR.
On the left is a nice association piece: a spirifer, a Greenops pygidium, and a Devonochonetes sp. . On the right is a high-spired Glyptotomaria.
A well-preserved Cimitaria recurva.
Deb found this wee Greenops that might be complete once I can remove some matrix. This one is barely a few millimetres long.
As Eldredgeops rana are not common here, I bucketed this roller.
Large cephalons from Dipleura dekayi. Finding them full as opposed to moults and disarticulated bits is an event. I think only one of us found a complete prone that day, while someone else found a complete one with the head disarticulated.
More Dipleura dekayi. I'll need to probe this piece a bit more to see if they might be complete (but I somehow doubt it).
A nautiloid and an ammonoid fragment.
With the collecting day over, it was time for us to get back to the Buffalo area. As is natural for us fossil collectors, we never miss an opportunity if we're collecting together to share some gifts. A massive amount of gift exchanges ensued! I was sure to hand out plenty of goodies from Arkona, as well as whatever Ordovician extras I had lying around. Pictured up here is a lovely Herkimer diamond from Dave. These quartz crystals are quite spectacular, and regularly have inclusions of anthraconite.
Another of Dave's wonderful gifts: an assortment of mostly brachs, bivalves, and gastropods from Cole Hill Road.
The other Dave put out a box for all of us to take whatever we fancied. This is a fern from the St Clair site, a site that is no longer open to public collecting.
Of course, little did I know that Tim remembered that Deb really liked those St Clair ferns, and so she received some pieces as well!
Tim gifted me a plethora of trilobites. Two new species on my list: Crotalochephalina gibbus (the Devonian phacopid from Morocco at the very top), Changaspis elongata (a wee corynexochid from the Cambrian, China), a full Greenops sp. from DSR in case I had no luck, and three nodular Eldredgeia venustus from Bolivia.
And the second bunch from Tim. A large Elrathia kingii with cheeks intact + impression, and the rest are Eldredgeops rana.
And Jay gave me a copy of the reprinted classic, Geology and Palaeontology of Eighteen Mile Creek by Grabau. The taxa listed in this one is pretty much the same as what is found at Penn Dixie, and some of those taxa are now outdated or reassigned. But it is indeed a classic from a real pioneer and giant of palaeontology.
DAY 3 - Penn Dixie
After two days collecting with Fossil Forum friends, it was now time for Deb and me to hit out on our own. Plans to visit another site on Sunday were nixed on account of weather... Yes, it was snowing in the Buffalo area! Deb went shopping in the morning, but by the afternoon the sun was out, so we figured we may as well play at Penn Dixie again. Although it was 10 C, the winds were bitterly cold.
Deb standing in the newly excavated zone we were all working on the Friday.
We decided to make a go of trying to find the elusive trilobite layer. This involved a great deal of hauling out slabs. Again, we treated the piles for the Experts event as off-limits.
The Smokes Creek layer is usually at or below the water table. This is what one of the gully areas looked like before I came in to rip out about 2 m wide of slabs. Sadly, the rock was far too dense, and shattered rather than split. Much of what was coming out was just bits and pieces anyway.
This trio of images shows the process required to access fresh material. As these slabs at the contact layer tend to interlock, it is important to kind the keystone slab to unlock them. In this instance, I've used the chisel to exploit and widen a crack running vertically. This one is tucked under another rock, so I had to use the pry bar to wiggle and jiggle it out. After that, I flip the rock over and scrutinize the underside; if there are trilobites or impressions thereof, I then carefully inspect the mini-domes at the site of extraction. As the water is muddy, this is largely done by touch. After that, it is time to remove another slab or split the ones I have.
Probably my best find of the day. The split runs right through the trilobite, but some crazy glue and prep will make this fairly large one turn out just fine.
This one came with a small price to pay. As I was tossing down a slab, it hit the pick end of my rock hammer, which then came at my face like a bullet. It struck and split my cheek, not far from my eye! It could have used a stitch or two, but I simply clamped it together with a bandaid.
Day 4 - Penn Dixie (Again)
After three days of slabbing, splitting, pounding with sledges, wrestling with pry bars, shovelling tons of overburden, my body just about had it! It was also our departure day, which meant we needed to get back on the road by 2 pm at the latest. So we agreed to inspect the newly excavated Bayview brachiopod area where, last October, we were pulling out buckets of brachs.
This stuff splits fairly easily - sometimes just with your hands. Trilobites like Greenops are much more common here, but the shale is so thin and fragile, and the trilobites usually only come out as disarticulated bits.
Brachiopods come out easily from the shale, if they haven't already weathered out and make for some easy picking. These are from about a minute of searching. Inasmuch as we agreed that we'd just do some light surface collecting, after 20 minutes we were getting bored with the brachs (we still have several hundred of them from October's visit),.so we went exploring back to the trilobite beds in search of a plentiful area.
Going through my splits, Deb finds this beauty.
A spot-check on some nearby rocks indicated that this particular area on the site might prove productive. Pictured here, after I removed the covering slab, is a very large dome. Domes at PD can either be full of trilobites or full of nothing.
Paydirt! We finally found the productive part of the layer. Although none of these are complete, it is strongly indicative of the presence of more assemblages in the depositional environment. Of course, it was almost time for us to leave just when we found the sweet spot. But we did manage to pull out a few rollers and near-completes that I haven't had a chance to photograph yet, but I think I've got the real highlights here in this post anyway.
And so it was back to Canada after a four day adventure. I was beyond sore, of course, but overall it was great to collect with friends old and new, enjoy the outdoors, and come away with treasures found and gifted.
Upcoming digs will likely be in the Arkona/Thedford area, and a trip to Bowmanville at the end of this month. Until then, time to manage some new backlog on the prep bench!
Although I said in my last blog post that the next post would feature the big spring dig, a lovely gift came in the mail today courtesy of Tony, a Fossil Forum friend. I had won a "guess the number" contest and chose an ammonite as my prize. Well, he added two Cambrian trilobites to the box, because that is just the generous guy he is.
The ammonite is from the Triassic of Nevada (possibly Frechites sp.). Let's have a closer look at the two ptychopariids...
The ventral view of a nice Bythicheilus typicum. This is described as a "fast-moving low-level epifaunal deposit feeder."
This is Bolaspidella reesae a lovely trilobite from the Wheeler Fm.
Ok, I promise the next post will be about the big dig. I just couldn't resist sharing this lovely gift.
The snow has (only briefly, I hope) returned once again and it is coming close to May. I'm hoping this will be the last blast of winter... but I think I've said that before! The weather looks like it will turn around for the weekend and return to normal seasonal values. And that is great news as I gear up for a four day dig at three sites in NY next weekend with plenty of Fossil Forum folks.
Speaking of Forum folks, one of our very generous members, Ralph, sent me a lovely package of trilobite partials he was able to pick up from a rock show. Ralph was also exceptionally kind in sending me (and several others) large boxes of Conasauga Fm matrix from Georgia, USA to play with, loaded with Cambrian trilobites.
Pictured here are three species of trilobite new to my expanding collection (standing at a whopping 76 distinct species now). Let's zoom in...
These are the pygidia of the Silurian phacopid, Trimerus delphinocephalus that occurs in the Rochester shale of NY. These trilobites are narrow and could grow quite large and somewhat resemble Dipleura dekayi in terms of shape.
A nice assortment of partials of the dalmanatid, Dalmanites limulurus, also from the Silurian Rochester shale. These ones do not preserve very well, and many of the ones for sale are missing the cuticle and their eyes, with some people choosing to restore them by adding eyes from other partials to make a frankenbug. That is fine if the seller is honest about the restoration (not all sellers are, though). One remark about the Rochester shale trilobites is that they tend to appear as though "listing" in the rock, leaning to the right or left.
Although missing some parts, this is another phacopid, Huntoniatonia sp. Without more diagnostic detail, drilling down to the species level may not be possible with this one. This one appears in the lower Devonian limestone of the Haragan Fm in Oklahoma, which is also famously known for producing some lovely spiny and horned trilobites like Kettneraspis and Dicranurus which usually only appear in Moroccan deposits. To some trilobite collectors, Oklahoma is like a little Morocco with the similarities between species, although with continental drift now thousands of kilometres apart from one another.
So, a lovely gift from Ralph once again keeps my spirits up while the weather is not cooperating fully with my digging plans.
I traded some material with a friend on the Fossil Forum and just received an immensely generous package filled with new trilobites that will be added to the gallery.
Pseudoasaphinus gosilicyensis - sitting atop a Proterocameroceras mishinagorense. From the Gosilitsy Quarry in Russia.
Modocia brevispina - Middle Cambrian, Wheeler shale, Utah
An Asaphus latus for me to prep! From Russia.
An Olenellus gilberti from the Cambrian. Pioche, Nevada.
Assemblage of Ptychagnostus richmondensis from the Wheeler shale in Utah. Mid Cambrian.
A Piochaspis sellata from the Chisholm shale of Pioche, Nevada (Cambrian).
The tiny Bolaspidella housensis from the Wheeler shale of Utah (Cambrian)
A fabulous pair of Itagnostus interstrictus from Utah's Wheeler shale (Cambrian)
The very last on my list, alphabetically, Zacanthoides sp. (?typicalis). Cambrian, Pioche, Nevada.
A complete surprise (apart from all the surprise new specimens above!), a genuine Spinosaurus tooth!
I ordered these cool membrane frames for cheap online, and that will help fill this:
Deb's birthday present to me, a lovely glass display cabinet to host all my lovely trilobites!
So, wow, what a great haul today!
Starting off the week with a bang, I had no fewer than three packages waiting for me when I got home. Two were purchases, and one was a gift from a dear Fossil Forum friend from the Netherlands.
First up, a "gold bug":
This phacopid is Metacanthina barrandei from the Couche Rouge, Maeder Region of Morocco. The trilobites in this layer are entirely replaced by chalcopyrite. In this case it is likely that the trilobite during preparation was painted or polished/buffed to appear in this fashion. It has two interesting features that distinguish this species: a tiny "spathe" at the end of the glabella (looks like it is sticking out its tongue) and a distinct occipital spike just below the cephalon. This one is not tiny, either, at about 90 mm tip to tip.
Similar to the trilobite I featured first last week, this is of the same genus. I welcome Gerastos ainrasifus to my collection. Just like the other proetid, it is fairly small at around 30 mm.
And now for the splendid gifts from my friend Pat overseas. This first is the classic, glabella-bulging Moroccan phacopid, Reedops sp. Some fabulous eye detail, yes, but that "shnozz" is something else!
This one is a bit tough to make out until I hook up the digital scope, but this barely 5 mm wide cephalon belongs to the very rare Diacanthaspis (Acanthalomina) minuta, a Silurian Odontopleurid (my first!) from Lodenice, Czech Republic. It has the tuberculate cephalic markings somewhat similar to various species of Ceraurus, but is more closely related to various Lichid trilobites.
And another lovely gift: the Ordovician asaphid Ogyiocaris dilatata. This was collected from the Oslo fjord area in Norway and are considered very rare.
And this one, well, this Belgian trilobite has yet to be formally described! It comes from the Hotton area, Ardennes, Belgium. I am guessing a phacopid of some kind, and it looks like I might give some matrix removal a try to see if I can find more of it in there.
And apart from these lovely trilo-gifts, I also received a cool Roman coin from the reign of Constantine II (337-340 AD), and shrapnel from the battlefield of the very famous - and one of the bloodiest - Battle of the Somme, which took place between the British (+Canada!) and the French against the Germans, July to November 1916. These are two pieces of non-trilobite history I very much cherish. It's been a fantastic day indeed!
Today's post is another that beats the winter blahs. The first is just some tinkering with some of my finds from the previous year, and the second is a generous gift from a forum member.
I am definitely running out of material to explore and prep, so I took a look at some of my one-of-a-kind specimens and noticed that maybe, just maybe, I could poke around my little Achatella achates from Brechin a bit more. I knew it was not complete, but finding even a cephalon of this Ordovician phacopid is quite uncommon.
This is a before and after sequence. Using a pin vice and my fancy microscope, I was able to remove some of the matrix to uncover more of the cephalon, but also the characteristic long genal spines of this species. Finding a whole one would be a trip-maker, for sure, but having an intact cephalon of this species is not too shabby.
The next item is the result of a very lovely gift by one of our very great forum members, Dave A. from NY state. I've been wanting one of these for some time. The fragments my friend Tim gave me last April managed to make me pine in finding a fuller one of these very interesting holmonotid bugs. So here is Dipleura dekayi in its semi-prone, semi-enrolled glory:
This one measures 10 cm along the axis if full prone, and so close to the upper end for how big these got. It is speculated by Whittington that it was a benthic critter that buried itself in sand with only its turret-like eyes protruding, hunting in a manner reminiscent of modern day crabs. This is one great Devonian delight for me.
Will there be more trilobites? There will be more trilobites, as they are en route as I type this. Stay tuned!
Winter is still dragging, and so one is forced to trade in the rock hammer for the credit card, or otherwise engage in some friendly fossil trades. Today was a good one for receiving a few new delights.
This might not be exciting to, well, anyone, but I quite desperately needed this prep tool. This is a double-collared pin vice that will make any of my pin-prepping much easier. Up until now, I've been holding the sewing needle between my fingertips, and after a while my hand starts to cramp. This tool will give me much more control. This tool didn't quite break the bank at about a dollar, free shipping.
This was part of a marvellous package sent to me by Hong Chan Ui from South Korea. I had sent him a package of trilobites last month with a few other fossil goodies, and he in turn sent me two trilobite species I don't have and also perked the package with some South Korean coins and tektites. How cool is that! The specimen above is a partial pygidium of the rare Ordovician asaphid, Dolerobasilicus sp. from Taebaek, Gongwon-Do, South Korea.
This glorious Devonian phacopid in the same package is Mrakibina cattoi from the El Oftal formation Jebel Mrakib, Ma'der, Alnif, Morocco. A near cousin of Greenops. The preservation detail and preparation is just remarkable.
This large Silurian phacopid was an eBay steal. Meet Coronocephalus gaoluoensis, coming in at 7 cm, or 3 inches long. Note the impressive pygidial spikes, if not the crazy number of segments. You usually find these as pygidia only. This is from Hunan Province, China.
These new acquisitions surely take a bit of the grinding gloom out of winter. But, as always, stay tuned: six or more bugs are still on their way, and it isn't even the official start of the 2018 collecting season yet!
Recently, Ralph J., a Fossil Forum friend, had made a trip to Georgia to collect some fossils from the Conasauga Formation, which is Cambrian in age. After he had posted his finds from the trip, I expressed delight at the seeming abundance of trilobites in the mudstone-shale, and he very kindly offered to send me some of the trilobites and some matrix to split. I was absolutely floored with his generousity - and this was only exceeded by the size of the box. There will be enough for Deb and me to split for a while.
And none too soon, either! The forecast is calling for flurries this Friday, which hopefully does not prematurely bring closure to such a memorable 2017 collecting season. I am dimly holding out hope that there will be at least one day left where Malcolm and I can get out to Arkona... just one last kick at the can before the snows fly.
At the moment, I am completely buried under a lot of grading and other work, so this gift arriving in the mail was certainly a great respite. I have not yet had an opportunity to get at the matrix, but here is a four panel picture of the newly added species to my burgeoning collection, Aphelaspis brachyphasis.
The matrix itself has a kind of slick, smooth, almost velvety texture. It splits fairly easily, and has a nice olive and tan colour to it, some with a deep orange staining, sometimes yellow (a very colourful matrix!). This layer has virtually nothing else visible to the eye except for this species of trilobite, and more uncommonly small fragments of a very tiny agnostid trilobite that perhaps only a magnifying lens will be able to spot.
These guys can be pretty small. The biggest ones are about under an inch, with plenty of others barely a millimetre or so long. The preservation is new to me. The trilobites are replaced entirely by minerals and in-filled with a kind of mud, and so you may find more detail in the impression than in the positive.
I've made the attempt above to put one of the very tiny ones (~1.5 mm) under the digital microscope to show some of the diagnostic details. Not the best picture, but you get the idea. Once I find the time to go through the matrix, I may have some better examples to show - and even if not, these are welcome new specimens to the collection.
Stay tuned as I am expecting three species of trilobite from Bolivia, and eventually my air scribe to work on some of my previous finds in the hopes of discovering some surprises.