New paper on crinoids of the Kalana Lagerstätte (Early Silurian) of central Estonia

May 14th, 2019

Bill Ausich (The Ohio State University), Oive Tinn (University of Tartu) have a paper that has just appeared:

Ausich, W.I., Wilson, M.A. and Tinn, O. 2019. Kalana Lagerstätte crinoids: Early Silurian (Llandovery) of central Estonia. Journal of Paleontology doi.org/10.1017/jpa.2019.27

It was an absolutely delightful project that was thoroughly documented in this blog. Last summer Bill and I traveled to Tartu, Estonia, to work with Oive on describing the extraordinary crinoids of the Silurian Kalana Lagerstätte. A Lagerstätte is a sedimentary deposit with exceptional fossil preservation. It is a privilege as a paleontologist to work on one. As you can see from the images, the crinoids here are well preserved indeed. I’ll let the paper’s abstract tell the story:

Abstract.—The Kalana Lagerstätte of early Aeronian (Llandovery, Silurian) age in central Estonia preserves a diverse shallow marine biota dominated by non-calcified algae. This soft-tissue flora and decalcified and calcified crinoids are preserved in situ in a lens of microlaminated, dolomitized micrite interbedded in a sequence of dolomitized packstones and wackestones. Although the Lagerstätte is dominated by non-calcified algae, crinoids (together with brachiopods and gastropods) are among the most common organisms that were originally comprised of a carbonate skeleton. Two new crinoids are described from this unit, Kalanacrinus mastikae n. gen. n. sp. (large camerate) and Tartucrinus kalanaensis n. gen. n. sp. (small disparid). Interestingly, these two crinoids display contrasting preservation, with the more common large camerate preserved primarily as a decalcified organic residue, whereas the smaller disparid is preserved primarily in calcite. Preservation was assessed using elemental mapping of C, Ca, S, and Si. Columns have the highest portion of Ca, once living soft tissue is indicated by C, S was dispersed as pyrite or associated with organics, and Si is probably associated with clay minerals in the matrix. This new fauna increases our understanding of the crinoid radiation on Baltica following Late Ordovician extinctions.

The top image and that above shows the new crinoid Kalanacrinus mastikae. Look at those gorgeous arms and the carbon films in the calyx that may represent internal organs. The species is named in recognition of Viirika Mastik, an Estonian graduate student who helped us in innumerable ways, and she was very patient with the sometimes clueless Americans! The genus, of course, is named for the deposit. (Scale bar is 5.0 mm.)

Here is another specimen of Kalanacrinus mastikae. Note the small angular, twiggy fossil below the calyx. I think it may be a green alga similar to the modern Hydrodictyon but marine and with larger cells.

Say hello to the new crinoid Tartucrinus kalanaensis. It’s pretty obvious how we came up with these names. Note again a carbon film in the calyx that may be from internal organs, possibly the anal sac. (Scale bar is 5.0 mm.)

The location and stratigraphy of the Kalana Quarry.

Several slabs of Kalana material. What a joy it was to study them for long, uninterrupted days.

The paleo lab at the University of Tartu, with Bill working in the background.

I loved this brand new Leica photomicroscope (model S9i).

Oive does excellent geochemistry, so she handled the elemental mapping. This example shows a close view of a Kalana crinoid column, with the elements C, Ca, S, and Si mapped. As stated in the abstract, columns have the highest portion of Ca, once living soft tissue is indicated by C, S was dispersed as pyrite or associated with organics, and Si is probably associated with clay minerals in the matrix.

Thank you to our excellent Estonian colleagues!

From the left is Oive Tinn, Mare Isakar, Bill, and Viirika Mastik.

New paper: Borings from the Silurian of Sweden — possibly the oldest deep-boring bivalves

April 27th, 2019

It was a delight to be a junior member of the team that produced this recent paper:

Claussen, A.L., Munnecke, A., Wilson, M.A. and Oswald, I. 2019. The oldest deep boring bivalves? Evidence from the Silurian of Gotland (Sweden). Facies 65: 26. https://doi.org/10.1007/s10347-019-0570-7

This may be the first paper for me where I’ve not yet met my co-authors. They are all from the GeoZentrum Nordbayern, Fachgruppe Paläoumwelt, Friedrich-Alexander Universität Erlangen-Nürnberg, Erlangen, Germany. This is where our recent graduate William Harrison is a graduate student. (He is clearly having a wonderful time there!)

Our team leader was the remarkable Lene Claussen. She did a prodigious amount of working and thinking for this study, which combines many of paleontology’s most recent tools, from isotopic analysis to micro-computed tomography. The abstract give us a synopsis of the story —

Abstract: Compared to modern counterparts, bioerosion is rare in Paleozoic reefs, especially macro-bioerosion. The unique and enigmatic Silurian reefs from Gotland (Sweden), composed of bryozoans and microbial laminates, show evidence of a large amount of bioerosion. The samples contain Trypanites trace fossils, as well as a large number of undescribed macroborings. Small articulated bivalve shells are preserved in some of these macroborings, identified from thin-sections. Three-dimensional images from micro-computed tomography (microCT) reveal an additional bivalve, which is occupying a bioerosion trace. This specimen is possibly contained in a different boring that can be classified as possibly clavate-shaped. Furthermore, evidence of nestling, such as a subsequent modification of the ichnofossils, the presence of bivalves that are much smaller than the trace, or the presence of additional specimens, is missing; therefore, it is most likely that the bivalves made the borings. This is evidence for the existence of deep-boring bivalves in the Silurian.

Top image is from Figure 3: Bioerosion traces from Nors Stenbrott, boreholes with bivalve shells in thin-section; a lateral cut through a bivalve shell (sample P3); b lateral cut through a bivalve shell (sample P13B).

From Figure 6: Processed three-dimensional microCT images of different boring traces from Nors Stenbrott, Trypanites borings in blue and the unknown ichnofossil in green; a all contained boreholes from sample SNS1; b all contained boreholes from sample Z9A, boring with bivalve with arrow.

I learned a great deal from this study and my new colleagues, especially about new techniques and the surprises they can reveal. Thank you, Lene and crew.

Bringing three new Silurian bryozoan species into the world

February 10th, 2019

I love being part of the scientific process of naming new organisms and placing them into the grand narrative that is the history of life. It is a kind of rescue — retrieving species from oblivion by giving them identities. Carolus Linnaeus, the father of taxonomy, said it well:

The first step in wisdom is to know the things themselves; this notion consists in having a true idea of the objects; objects are distinguished and known by classifying them methodically and giving them appropriate names. Therefore, classification and name-giving will be the foundation of our science.

The bryozoans described in this post are from a project led by my very accomplished bryozoologist friend Andrej Ernst at the University of Hamburg, Germany (above). In the summer of 2015, Andrej and I met up with our colleague Carl Brett (University of Cincinnati) to collect bryozoans from the Lower Silurian (Aeronian) of western New York. My fieldwork was supported by a grant from the Luce Fund at The College of Wooster. We had a very productive time and saw much geology and paleontology, as you can see from these August 2015 blog posts. That fieldwork was followed by Andrej’s prodigious lab work with the bryozoans. The results have now appeared in the Journal of Paleontology.

The abstract: Thirteen bryozoan species are described from the Brewer Dock (Hickory Corners) Member of the Reynales Formation (lower Silurian, Aeronian) at the locality Hickory Corners in western New York, USA. Three species are new: trepostomes Homotrypa niagarensis n. sp. and Leioclema adsuetum n. sp. and the rhabdomesine cryptostome Moyerella parva n. sp. Only one species, Hennigopora apta Perry and Hattin, 1960, developed obligatory encrusting colonies whereas the others produced erect ramose colonies of various thicknesses and shapes: cylindrical, branched, and lenticular. Bryozoans display high abundance and richness within the rock. This fauna is characteristic of a moderately agitated environment with a stable substrate. The identified species reveal paleobiogeographic connections to other Silurian localities of New York as well as Ohio and Indiana (USA) and Anticosti (Canada).

The top photo in this post is one of the new bryozoans, the trepostome Homotrypa niagarensis. The images are from Figure 8, with the caption: (2) branch oblique section, holotype SMF 23.470; (3) rock thin section with transverse and oblique sections of branches, holotype SMF 23.472; scale bars are 3 mm and 5 mm respectively.

Above is the new trepostome Leioclema adsuetum. The image is from Figure 10, with the caption: (1) longitudinal section of exozone showing autozooecia, mesozooecia, and acanthostyles, paratype SMF 23.553; scale bar is 0.5 mm.

This is the third new species, the cryptostome Moyerella parva. The images are from Figure 11, with the caption: (3) longitudinal section of a colony segment with a pointed base and widened proximal part showing medial axis and autozooecia, holotype SMF 23.559; (4) tangential section showing autozooecial apertures, tubules, and tectitozooecia, holotype SMF 23.559; scale bars are 0.5 mm and 0.2 mm respectively.

The paper is about more than these new species, of course. There are other bryozoans assessed, and Carl Brett’s stratigraphy section is magnificent and a new resource for the area. The new taxa, though, are worth celebrating by themselves.

Thank you to Andrej and Carl for being such good colleagues. I hope we return to the Silurian of western New York for more work.

Reference:

Ernst, A., Brett, C.E. and Wilson, M.A., 2019. Bryozoan fauna from the Reynales Formation (lower Silurian, Aeronian) of New York, USA. Journal of Paleontology, doi.org/10.1017/jpa.2018.101.

Sunday at the University of Tartu Natural History Museum — this time as tourists

August 5th, 2018

Tartu, Estonia — Bill Ausich and I returned to the Natural History Museum today to tour the public exhibits. It was hard to not make it into a study trip, though, for our research. I suppose since our “work” is so enjoyable it is difficult to separate it from a holiday. Above, for example, is a display of our favorite rhombiferan, Echinosphaerites aurantium of the Estonian Upper Ordovician.

There is a display about the Kalana Lagerstätte that we are studying.

Here is the museum description of the Lagerstätte.

And a close-up of some crinoids (“meriliilia”, sea lilies) from the Kalana.

It is a fun museum with a very thorough geology section, including meteorites you can touch (a favorite of mine). It has what is now an old-fashioned style of emphasizing actual specimens that Bill and I appreciated. There is a large biology section with much taxidermy and mounted skeletons. One of the featured exhibits is a rare “rat king” (see below), which you must look up!

Back to work in the University of Tartu Geology Department

August 3rd, 2018

Tartu, Estonia — Today Bill Ausich and I returned to the geology lab on the university campus to continue our work on the Kalana Lagerstätte crinoids. There is Bill above working on specimens.

I spent most of the day working with this beautiful Leica photomicroscope (model S9i). It is the most intuitive photomicroscope I have ever seen. The images are superb. I want.

Here I am at the microphotography station, looking wistfully outside.

We don’t have anything new to report today, so here’s an image of one of the best Kalana crinoids.

This is my favorite specimen because it is squashed in a way that separated the calyx plates to make them easier to see.

The calyx is on the left side of this specimen. The pinnules from the arms are preserved so well here they look like hair. Note the small angular fossil just below the crinoid on the right. These are common in the Lagerstätte, often appearing to be attached to crinoids. We think they may be green algae, possibly like the modern Hydrodictyon but marine — and with larger cells. Another mystery in this fossil assemblage.

We’ve now completed a week in Tartu. The Kalana crinoid project has gone especially well. Thank you to graduate student Viirika Mastik who collected most of the Kalana crinoids, and to her supervisor Oive Tinn. They have helped us immensely in the lab.

Back to the paleontology lab in Tartu, Estonia

August 1st, 2018

Tartu, Estonia — Disconcertingly it says “chemistry”, but there really is a geology department inside this building on the University of Tartu campus.

The Geology Department is part of the Institute of Ecology and Earth Sciences. We are very impressed with their facilities and friendly academics.

Here again is the lab room loaned to us for our stay. Bill is working in the back. The crinoid-rich specimens from the Kalana Lagerstätte at the Kalana Quarry (Silurian, Llandovery, Aeronian) are spread out through the room. We are very fortunate to have such space.

This is my workstation with my trusty laptop. The Leica microscope is fantastic.

We are examining the crinoids preserved on this dolomicritic limestone slabs that were carefully collected by university staff from Kalana Quarry in central Estonia. The crinoids are quickly apparent because their beautiful hair-like pinnulate arms are visible.

I’ll write more paleontological details later, but here is the part-counterpart of the best specimen of what will be a new crinoid taxon. From the bottom is the cylindrical stem, followed upwards by the conical calyx, and then the long arms with thin extensions called pinnules. You can also see some black smears of carbonaceous material on the right. These specimens are compressed and mostly decalcified. Their preservation is still a bit mysterious to us.

This is why we’re here so far from home!

Here is an image of the Kalana Quarry, where the Lagerstätte is found, from this wonderful Estonian geology website.

Fieldwork in Estonia, with a bonus visit to Narva

July 31st, 2018

Tartu, Estonia — Today Bill and I had a spectacular geology and culture field trip in northeastern Estonia. As you can see in the images, the weather was excellent, if a little warm. Our Estonian hosts took us from Tartu to several places north and east to the border with Russia. Our fieldwork in an oil shale quarry is shown above, but first our journey there —

Lake Peipsi (or Lake Peipus) is near Tartu. It is one of the largest freshwater lakes in Europe, with the Russian border running down its center. We stopped briefly for this view. It looks like one of North America’s Great Lakes from here. There is much history along these shores.

This is the Kiviõli Concentration Camp Holocaust Memorial near our collecting site today. The 20th century history of this region, especially during World War II, is notably grim and brutal. Relatively little has been published on the German concentration camps in Estonia.

This is the oil shale mine we visited near Põhja-Kiviõli in northern Estonia. The oil shales, in the form of kukersite, are the brown units in the top half of the outcrop. The shales are dug from these pits and then separated from the limestones, which appear light gray. The pits fill quickly with water, so there are massive pumps continually working nearby.

A closer view of an oil shale outcrop. These units are Late Ordovician in age (Sandbian) and nearly unique to Estonia. They are very rich in organic material — up to 55% of the rock. The oil shales are used in a variety of ways for energy and petroleum products.

Finding specimens of the spherical rhombiferan echinoderm Echinosphaerites was one of our goals for this trip. Here is one in limestone. The best are those that are in the oil shale because they pop free of the matrix. We didn’t find very many, though.

Giant bryozoans were surprisingly common in the oil shales. This is the base of a large trepostome. We found many of these bryozoans with beautiful borings. It was a good collecting site.

Here are our delightful Estonian hosts at lunch following fieldwork. From left to right: Olev Vinn (a colleague since 2006), Ingrid Vinn, and Mare Isakar.

Much to our surprise we were able to go to the storied easternmost Estonian city of Narva. This was very much a treat. Narva sits along the Narva River, which is the border with Russia. The city has a high concentration of Russian-speakers and a distinct Estonian-Russian culture. Its history has been, needless to say, complex even to present times.

This is Hermann Castle, also called Narva Castle, the focus of our visit. Hermann Castle is the blocky, high structure. To the right is visible another castle on the other side of the Narva River (see below).

This is that Russian castle opposite the Hermann Castle on the castle on the other bank of the Narva River. It is the Ivangorod Fortress. It makes for quite a striking boundary at the western edge of Russia.

The Narva River between the two castles, looking upstream. The Ivangorod Fortress is on the left. This is effectively the boundary between East and West in Europe.

The Narva border crossing bridge between Estonia on the left and Russia on the right. This is the view from the top of the Hermann Castle. At this point my phone gave me a message: “Welcome to the Russian Federation”.

The interior of the Hermann Castle is a museum. I thought these stone cannon balls were geologically interesting, considering that earlier this summer I saw their equivalents in Wales. Note my foot for scale.

On the way back to Tartu, we visited the town of Sillamäe on the Baltic coast. During Soviet times factories in Sillamäe extracted uranium oxides from local oil shales and then from other ores mined throughout the Soviet Empire. Because of the high concentration of scientists and engineers, this town was built with, shall we say, higher architectural and aesthetic standards than the usual Soviet constructions. It was a “closed town” forbidden to foreigners or even most Estonians.

This is a 1987 statue in Sillimäe celebrating its atomic achievements. By then this town produced almost 100,000 tons of uranium oxides for Soviet nuclear weapons and energy plants. It all stopped in 1989, and when Estonia reclaimed the area two years later there were serious contamination problems to solve. [Update: Cheryl Rofer, Los Alamos National Laboratory (retired), added a comment and a link to her story about the clean-up: Averting a Baltic Sea Disaster. It is an excellent read!)

What a rich trip this was. Thank you again to Olev, Ingrid and Mare.

Starting work in Estonia

July 30th, 2018

Tartu, Estonia — Ah, fossils at last! Bill Ausich and I are here to explore several topics, but the main one is describing the crinoids in a Silurian (Aeronian) Konservat Lagerstätte at Kalana Quarry in central Estonia. Much more on this later, but above is one of the crinoids, from the stem to the calyx to the pinnulate arms. The preservation is very odd, with most of the original calcite dissolved away and considerable carbonization and, maybe, some recrystallization. (Much of the list of preservation modes we teach!)

We’re working in a beautiful teaching lab at the University of Tartu. We have plenty of space to lay out the specimens collected by the geologists here. (These particular quarry beds are no longer accessible.) The microscopes are new and the best student models I’ve seen.

Today was mostly orientation for us in the lab. After dinner we walked down to the Emajõgi River, which runs through the campus and has been very important in Estonian history. Its name means “Mother River”. Beautiful.

Wooster’s Fossils of the Week: Peanut worms from the Silurian of Illinois

February 3rd, 2017

1-lecthaylus-gregarius-5-copyThis week’s fossils are a set of cool sipunculan worms from the Lockport Shale Member of the Racine Formation (Wenlockian, Silurian) of Blue Island, Illinois (which, it turns out, is not an island.). This is Lecthaylus gregarius Weller, 1925. (There is a common misspelling of the genus name as “Lecathylus”, which is how it is labeled in our collection.) They are masses of partially-carbonized bodies and external molds in a very fine-grained matrix. They are well known from this particular fossil-lagerstätte (a fossil fauna of remarkable preservation) in northern Illinois.

The Phylum Sipuncula did not often make it into the fossil record because of their entirely soft bodies, but a few are preserved way back in the Cambrian Chengjiang and Burgess Shale faunas. They show virtually no evolutionary changes in their long run to today, at least not in their outer form. They are commonly known as “peanut worms”.

2-lecthaylus-gregarius-2This is an example of the preservation modes: a black carbon film that has mostly flaked away, leaving behind a detailed external mold of the squashed peanut worms.

3-lecthaylus-gregarius-1Sipunculan bodies are divided into a main thick posterior trunk and a narrow, retractable anterior “introvert”. We’re looking here at the anterior introvert of Lecthaylus gregarius.

4-lecthaylus-gregarius-3-copyThis is the squat trunk of Lecthaylus gregarius.

5-themiste_petricola_evertedHere is the modern sipunculan Themiste petricola with introvert extended. It is the same basic plan as the Silurian Lecthaylus gregarius. Image from Wikipedia courtesy of Tomás Lombardo and Guillermo A. Blanco.

6-themiste_petricola_invertedThe modern sipunculan Themiste petricola with its introvert retracted. Image from Wikipedia courtesy of Tomás Lombardo and Guillermo A. Blanco.

stuart-weller-1870-1927Lecthaylus gregarius was described and named by Stuart Weller (1870-1927), an American paleontologist and geologist. He was born in the small town of Maine, New York. He earned a Bachelor’s degree in geology at Cornell University in 1894 followed by a PhD at Yale in 1901. Shortly after his Cornell degree, though, Weller traveled to the University of Chicago, where he worked his way through the ranks from a research associate to a full professor of Paleontology and Geology in 1915. He was also the director of the Walker Museum at the University of Chicago, and in 1926 he was president of the Paleontological Society. One of his sons, J. Marvin Weller (1899-1976) had a remarkably similar career as a stratigrapher and paleontologist.

References:

Kluessendorf, J. 1994. Predictability of Silurian Fossil‐Konservat‐Lagerstatten in North America. Lethaia 27: 337-344.

Roy, S.K. and Croneis, C. 1931. A Silurian worm and associated fauna. Field Museum of Natural History, Geological Series IV(7): 229-247.

Weller, S. 1925. A new type of Silurian worm. Journal of Geology 33: 540-544.

Wooster’s Fossils of the Week: New Early Silurian crinoids from Estonia

September 16th, 2016

1 Hilliste crinoidsIt has been a good year for new fossil taxa on this blog. I’m pleased to present a fauna of Early Silurian crinoids from the Hilliste Formation (Rhuddanian) exposed on Hiiumaa Island, western Estonia. They are described in a paper that has just appeared in the Journal of Paleontology (early view) written by that master of Silurian crinoids, Bill Ausich of Ohio State University, and me, his apprentice.

Here’s the simplified caption for the above composite image: Rhuddanian crinoids from western Estonia: (1) Bedding surface comprised primarily of crinoid columnals and pluricolumnals; (2) Radial circlet of an unrecognizable calceocrinid; (3) Basal circlet of an unrecognizable calceocrinid; (4) Holdfast A: Virgate radices anchored in coarse skeletal debris; (5) Holdfast D: Simple discoidal holdfast cemented to a bryozoan; (6, 7, 8) Hiiumaacrinus vinni n. gen. and n. sp.: 6, D-ray lateral view of calyx, 7, E-ray lateral view of calyx, 8, basal view of calyx; (9) Holdfast B: Dendritic holdfast in coarse skeletal debris; (10) Eomyelodactylus sp. columnal; (11) Holdfast C: Simple discoidal holdfast cemented to a tabulate coral; (12) Two examples of Holdfast E: Stoloniferous holdfasts cemented to a tabulate coral; (13) Protaxocrinus estoniensis n. sp. lateral view of partial crown, top of radial plate indicated by line.

Here is the abstract: “Rhuddanian crinoid faunas are poorly known globally, making this new fauna from the Hilliste Formation of western Estonian especially significant. The Hilliste fauna is the oldest Silurian fauna known from the Baltica paleocontinent, thus this is the first example of the crinoid recovery fauna after the Late Ordovician mass extinction. Hiiumaacrinus vinni n. gen. n. sp., Protaxocrinus estoniensis n. sp., Eomyelodactylus sp., calceocrinids, and five holdfast types are reported here. Although the fauna has relatively few taxa, it is among the most diverse Rhuddanian faunas known. Similar to other Rhuddanian crinoid faunas elsewhere, the Hilliste crinoid fauna contains crinoids belonging the Dimerocrinitidae, Taxocrinidae, Calceocrinidae, and Myelodactylidae; most elements of the new fauna are quite small, perhaps indicative of the Lilliput Effect.”
3 Hilliste diagramNo crinoid paper is complete without camera lucida drawings (scale bar for all figures is one mm): (1) Hiiumaacrinus vinni n. gen. and n. sp.; (2) Radial circlet of an unrecognizable calceocrinid; (3) Basal circlet of an unrecognizable calceocrinid; (4) Protaxocrinus estoniensis n. sp.
4 Olev062511There are two new species and one new genus here. Hiiumaacrinus vinni is named first after the lovely Estonian island where the species is found, and then after our good friend and colleague Olev Vinn (above) at the University of Tartu. Olev first introduced me to the Ordovician and Silurian of Estonia, and then was an excellent field companion for Bill and me on our Estonian field trips.
2 Hiiumaa mapA reminder where Hiiumaa Island is, and for that matter, the nation of Estonia.

5 HillisteQuarry071312Here is Hilliste Quarry on Hiiumaa Island. Still one of my favorite places to work. Very, very quiet.

6 HillisteAusich071112Here is Bill Ausich in the quarry during our 2012 expedition. The pose is known among paleontologists as “the Walcott“.

7 Holdfasts071112Here is one of the specimens collected by Bill in July of 2012. You may recognize this field scene as figure 12 in the top image of this post. These are two examples of crinoid holdfasts on a tabulate coral.

Please welcome Hiiumaacrinus vinni and Protaxocrinus estoniensis to the paleontological world!

References:

Ausich, W.I. and Wilson, M.A. 2016. Llandovery (Early Silurian) crinoids from Hiiumaa Island, Estonia. Journal of Paleontology (early view).

Ausich, W.I., Wilson, M.A. and Vinn, O. 2012. Crinoids from the Silurian of Western Estonia (Phylum Echinodermata). Acta Palaeontologica Polonica 57: 613‒631.

Ausich, W.I., Wilson, M.A. and Vinn, O. 2015. Wenlock and Pridoli (Silurian) crinoids from Saaremaa, western Estonia (Phylum Echinodermata). Journal of Paleontology 89: 72‒81.

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