A new paper has appeared: A rugose coral – bryozoan association from the Lower Devonian of NW Spain.

June 14th, 2019

I’m proud to be an author with my two Spanish colleagues, Consuelo Sendino and Juan Luis Suárez Andrés, of a paper just out in the latest issue of Palaeogeography, Palaeoclimatology, Palaeoecology (we call it “Palaeo-cubed”). I’ll let the abstract tell the story (with some embedded links):

“A new rugose coralcystoporate bryozoan association is here described from the Devonian of NW Spain. This is the first evidence of intergrowths between Devonian rugose corals and bryozoans. In this case bryozoans provided a suitable substrate for the settlement of corals, which were subsequently encrusted by the bryozoans. The hypothesis of intergrowth between living organisms is supported by the absence of encrustation of the rugose coral calices by the cystoporates. We suggest that the association was specific and developed through chemical mediation. This symbiosis was facultative for the bryozoans but likely not for the corals. The association provided the bryozoan host with additional substrate for encrustation as well as protection from various predators, and it allowed the rugose corals to grow in a muddy environment and benefit from the feeding currents of the bryozoans.”

The above images show some of these specimens of corals intergrown with bryozoans. The caption from Figure 2: Intergrowth of fistuliporid bryozoans and rugose corals from the Aguión Formation of Asturias, NW Spain. A. General view of DGO12902. B. General view of MMAGE0033. C. Detail of the corallite, MMAGE0032. D. Magnified corallite of the right side, MMAGE0033.

This cartoon from the paper shows the process in which a coral larva (planula) lands on a living bryozoan, somehow survives the encounter, and then the coral grows together with the surrounding bryozoan colony. The fun part is sorting out the biological and evolutionary context of this relationship.

I thank my colleagues Consuelo and Juan for inviting me into this project. I learned a lot that will be applied to similar intergrowing situations in the fossil record.

Sendino, C., Suárez Andrés, J.L. and Wilson, M.A. 2019. A rugose coral – bryozoan association from the Lower Devonian of NW Spain. Palaeogeography, Palaeoclimatology, Palaeoecology 530: 271-280.

Birthplace of the Sandusky River

April 6th, 2019

I’ve long appreciated river confluences where two flows join to make a third, “new” river. The most impressive confluence I’ve visited is where the Bhagirathi and Alaknanda Rivers meet to produce the iconic Ganges at Devprayag, India. (The second image in the Wikipedia article is mine.) Of course, such places are only changes in our human geographical classifications. It is a subjective decision to determine which confluence merits naming a new river or stream, essentially marking its “birthplace”.

Today Nick Wiesenberg, his father David, and I had a delightful hike through Lowe-Volk Park in Crawford County, Ohio — about an hour’s drive west of Wooster. Within this small park Paramour Creek and the smaller Allen Run join to make the Sandusky River, as shown above. The Sandusky River then flows about 130 miles north into Lake Erie. The Sandusky has played a critical role in 18th and early 19th century Ohio history, so it was a privilege to visit its origin. The weather was perfect for a short hike in the woods.

Lowe-Volk Park was established around this confluence and three 19th century quarries in the Berea Sandstone, a massive Upper Devonian unit used throughout northeastern Ohio as a building stone. The quarries are now eroded walls of bedrock slowly being covered by vegetation.

As always on trips like this, Nick and David teach me many new things. For example, I knew honeylocust trees are festooned with nasty, long thorns, as you can see on this trunk. What I didn’t know was that these defensive structures evolved in response to animals no longer around — mastodons!The thorns on the honeylocust trunks go as high as a mastodon could reach, and no more. This was apparently part of a coevolutionary relationship in which the trees had no interest in being pushed over by these pachyderms for their delicious seedpods while they were still ripening on their branches. After the seedpods matured and fell to the ground it was to the benefit of the trees for the mastodons to eat them and pass the seeds through their guts for planting elsewhere, hence their sweetness. Now the thorns mount a defense against lumbering ghosts.

Speaking of ghosts, this area was a bloody battleground numerous times, most notably in 1782 at the end of the Revolutionary War. The painting above hangs in the park visitor center. It shows Colonel William Crawford leading an American military expedition against Indian tribes living along the Sandusky River. The Indians, and their British allies, were well informed about this attempted surprise attack and beat it back decisively, giving the name to the fight “The Battle of Sandusky” or “Crawford’s Defeat”. Crawford himself was captured very near the present park. He had a gruesome end in captivity, which was a response to previous atrocities on the part of earlier American raiders who did not, ironically, include poor Colonel Crawford.

Wooster’s Fossils of the Week: Bivalve escape trace fossils (Devonian and Cretaceous)

April 7th, 2017

It is time again to dip into the wonderful world of trace fossils. These are tracks, trails, burrows and other evidence of organism behavior. The specimen above is an example. It is Lockeia James, 1879, from the Dakota Formation (Upper Cretaceous). These are traces attributed to infaunal (living within the sediment) bivalves trying to escape deeper burial by storm-deposited sediment. If you look closely, you can see thin horizontal lines made by the clams as they pushed upwards. These structures belong to a behavioral category called Fugichnia (from the Latin fug for “flee”). They are excellent evidence for … you guessed it … ancient storms.
The specimens above are also Lockeia, but from much older rocks (the Chagrin Shale, Upper Devonian of northeastern Ohio). Both slabs show the fossil traces preserved in reverse as sediment that filled the holes rather than the holes themselves. These are the bottoms of the sedimentary beds. We call this preservation, in our most excellent paleontological terminology, convex hyporelief. (Convex for sticking out; hyporelief for being on the underside of the bed.)

The traces we know as Lockeia are sometimes incorrectly referred to as Pelecypodichnus, but Lockeia has ichnotaxonomic priority (it was the earliest name). Maples and West (1989) sort that out for us.
Uriah Pierson James (1811-1889) named Lockeia. He was one of the great amateur Cincinnatian fossil collectors and chroniclers. In 1845, he guided the premier geologist of the time, Charles Lyell, through the Cincinnati hills examining the spectacular Ordovician fossils there. He was the father of Joseph Francis James (1857-1897), one of the early systematic ichnologists.

References:

James, U.P. 1879. The Paleontologist, No. 3. Privately published, Cincinnati, Ohio. p. 17-24.

Maples, C.G. and Ronald R. West, R.R. 1989. Lockeia, not Pelecypodichnus. Journal of Paleontology 63: 694-696.

Radley, J.D., Barker, M.J. and Munt, M.C. 1998. Bivalve trace fossils (Lockeia) from the Barnes High Sandstone (Wealden Group, Lower Cretaceous) of the Wessex Sub-basin, southern England. Cretaceous Research 19: 505-509.

[Originally published January 29, 2012]

Wooster’s Fossil of the Week: Mysterious tentaculitids (Devonian of Maryland)

March 3rd, 2017

The sharp little conical fossils above are common Paleozoic fossils, especially in the Devonian. They are tentaculitids now most commonly placed in the Class Tentaculitoidea Ljashenko 1957. Tentaculitids appeared in the Ordovician and disappeared sometime around the end of the Carboniferous and beginning of the Permian. These specimens are from the Devonian of Maryland.

The systematic placement of the tentaculitids has been controversial. Their straight, narrow shells are usually ornamented by concentric rings, and many had septa (thin shelly partitions) inside the cones. The microstructure of the shells is most interesting — it looks very much like that of brachiopods and bryozoans. For this reason and several others, several of my colleagues and I believe the tentaculitids were lophophorates (animals that filter-feed with a tentacular device called a lophophore). They may thus be related to other problematic tubeworms like microconchids and cornulitids (Taylor et al., 2010).

Tentaculitids from the New Creek Limestone (Lochkovian, Early Devonian) of New Creek, West Virginia.

Knowing how the tentaculitids fit into an evolutionary scheme, though, has not helped us figure out what they did for a living. The figure below, from Cornell et al. (2003), shows these funny cones in just about every lifestyle imaginable!

References:

Cornell, S.R., Brett, C.E. and Sumrall, C.D. 2003. Paleoecology and taphonomy of an edrioasteroid-dominated hardground association from tentaculitid limestones in the Early Devonian of New York: A Paleozoic rocky peritidal community. Palaios 18: 212-224.

Taylor, P.D., Vinn, O. and Wilson, M.A. 2010. Evolution of biomineralization in ‘lophophorates’. Special Papers in Palaeontology 84: 317-333.

[Originally published May 29, 2011.]

Wooster’s Fossil of the Week: A stromatoporoid (Middle Devonian of central Ohio)

February 17th, 2017

Stromatoporoids are very common fossils in the Silurian and Devonian of Ohio and Indiana, especially in carbonate rocks like the Columbus Limestone (from which the above specimen was collected). Wooster geologists encountered them frequently on our Estonia expeditions in the last few years, and we worked with at least their functional equivalents in the Jurassic of Israel (Wilson et al., 2008).

For their abundance, though, stromatoporoids still are a bit mysterious. We know for sure that they were marine animals of some kind, and they formed reefs in clear, warm seas rich in calcium carbonate (DaSilva et al., 2011). Because of this tropical habit, early workers believed they were some kind of coral, but now most paleontologists believe they were sponges. Stromatoporoids appear in the Ordovician and are abundant into the Early Carboniferous. The group seems to disappear until the Mesozoic, when they again become common with the same form and life habits lasting until extinction in the Late Cretaceous (Stearn et al., 1999).

The typical stromatoporoid has a thick skeleton of calcite with horizontal laminae, vertical pillars, mounds on the upper surface called mamelons, and dendritic canals called astrorhizae shallowly inscribed on the mamelons. These astrorhizae are the key to deciphering what the stromatoproids. They are very similar to those on modern hard sponges called sclerosponges. Stromatoporoids appear to be a kind of sclerosponge with a few significant differences (like a calcitic instead of an aragonitic skeleton).

Stromatoporoid anatomy from Boardman et al. (1987).

Top surface of a stromatoporoid from the Columbus Limestone showing the mamelons.

There is considerable debate about whether the Paleozoic stromatoporoids are really ancestral to the Mesozoic versions. There may instead be some kind of evolutionary convergence between two groups of hard sponges. The arguments are usually at the microscopic level!

The stromatoporoids were originally named by Nicholson and Murie in 1878. This gives us a chance to introduce another 19th Century paleontologist whose name we often see on common fossil taxa: Henry Alleyne Nicholson (1844-1899). Nicholson was a biologist and geologist born in England and educated in Germany and Scotland. He was an accomplished writer, authoring several popular textbooks, and a spectacular artist of the natural world. Nicholson taught in many universities in Canada and Great Britain, finally ending his career as Regius Professor of Natural History at the University of Aberdeen.

Henry Alleyne Nicholson (1844-1899) from the University of Aberdeen museum website.

References:

Boardman, R.S., Cheetham, A.H. and Rowell, A.J. 1987. Fossil Invertebrates. Wiley Publishers. 728 pages.

DaSilva, A., Kershaw, S. and Boulvain, F. 2011. Stromatoporoid palaeoecology in the Frasnian (Upper Devonian) Belgian platform, and its applications in interpretation of carbonate platform environments. Palaeontology 54: 883–905.

Nicholson, H.A. and Murie, J. 1878. On the minute structure of Stromatopora and its allies. Linnean Society, Journal of Zoology 14: 187-246.

Stearn, C.W., Webby, B.D., Nestor, H. and Stock, C.W. 1999. Revised classification and terminology of Palaeozoic stromatoporoids. Acta Palaeontologica Polonica 44: 1-70.

Wilson, M.A., Feldman, H.R., Bowen, J.C. and Avni, Y. 2008. A new equatorial, very shallow marine sclerozoan fauna from the Middle Jurassic (late Callovian) of southern Israel. Palaeogeography, Palaeoclimatology, Palaeoecology 263: 24-29.

[Originally published on October 30, 2011]

Wooster’s Fossil of the Week: An atrypid brachiopod from the Devonian of Spain

April 15th, 2016

1 Atrypid dorsal Lr Couvinian M Dev El Pical Leon SpainOur featured fossil this week is another gift from brachiopod enthusiast Clive Champion of England. This fine specimen of Atrypa sp. was collected from the Middle Devonian (Lower Couvinian) exposed at El Pical, Leon, Spain. Atrypa is the emblematic genus of the atrypid brachiopods, which were common in the Devonian around the world. They were also prominent in the Late Ordovician of the Cincinnati region, as seen here and here. We are looking at the dorsal valve in the above view.

2 Atrypid spiraliaThis particular specimen is not notable for its special beauty (it is, after all, exfoliated and a bit misshapen), but for the view it provides of an internal feature: the spiral brachidium, sometimes called the spiralia. This was a ribbon of calcite that supported the lophophore, a tentacular apparatus used in filter-feeding. We see it here because the dorsal valve eroded away, exposing the inside of the shell. Our friends at The Falls of the Ohio have another specimen showing the spiral lophophore of an atrypid.

3 Atrypid ventralThis is a view of the flat ventral valve of our atrypid brachiopod. Inside during life the spiral lophophore would have looked like two springs perpendicular to the floor of this valve.

Thank you again, Clive, for the beautiful and inspiring brachiopods!

References:

Bose, R. 2013. A geometric morphometric approach in assessing paleontological problems in atrypid taxonomy, phylogeny, evolution and ecology, p. 1-9. In: Biodiversity and Evolutionary Ecology of Extinct Organisms. Springer, Berlin and Heidelberg.
Rudwick, M.J.S. 1960. The feeding mechanisms of spire-bearing fossil brachiopods. Geological Magazine 97: 369-383.

 

Wooster’s Fossil of the Week: A mystery from the Middle Devonian of Ontario, Canada

March 11th, 2016

Hungry Hollow 1This week’s fossil is a strange one. Mr. Darrell Ellis collected the above tiny specimen from the Hungry Hollow Member (Middle Devonian) at the famous Hungry Hollow location near Arkona, Ontario. (He also took this excellent photograph.) In the classic way exploratory paleontology works, he contacted an expert, my friend Olev Vinn at the University of Tartu in Estonia. Olev was puzzled, having never seen anything like it, so he sent the image to me. I was baffled. Darrell next sent me the actual specimen, which I examined an photographed. I could see that it is a calcitic spiral, flattened tube extending from a discoidal holdfast at its proximal end. I then passed images on to another buddy and expert, Paul Taylor at the Natural History Museum in London. The form is new to Paul as well, and he suggested it might be an odd microconchid, a twisty tube-dweller now extinct. That made sense, even if no microconchid like this has ever been described. We know that some microconchids did grow tubes extended upwards (such as Helicoconchus from the Permian of Texas, described earlier in this blog). Since we need to see the microstructure of the calcitic tube to support the hypothesis that this is a microconchid, I then sent the specimen to yet another friend, Michał Zatoń at the University of Silesia in Poland. He will examine the specimen with a scanning electron microscope (SEM). This is citizen science at work. Thank you, Darrell, for donating this specimen to science. It is also a reflection of how small scientific networks exchange ideas, information and specimens — Olev, Paul and Michał have been featured in this blog many times; we are old friends and colleagues with similar interests and diverse skill sets (and equipment!).

Hungry Hollow 2This is a closer view of the top of the spiral. We hope that Michał will be able to see the microstructure of the calcite on these broken surfaces.

Hungry Hollow 3This is the simple holdfast of this specimen. The tube began to grow  upwards very early in its ontogeny.

If you have ever seen a specimen like this before, whole or partial, please let me know in the comments or by email. We have only this one specimen that is clearly “new to science”. Other collectors and paleontologists may have bits of this they did not recognize before.

Again, thank you to Darrell Ellis for his sharp eyes, eagerness to contact experts, and generosity!

References:

Wilson, M.A., Vinn, O. & Yancey, T.E. 2011. A new microconchid tubeworm from the Artinskian (Lower Permian) of central Texas, USA. Acta Palaeontologica Polonica 56: 785-791.

Zatoń, M. & Vinn, O. 2011. Microconchids and the rise of modern encrusting communities. Lethaia 44:5-7.

Zatoń, M., Wilson, M.A. and Vinn, O. 2012. Redescription and neotype designation of the Middle Devonian microconchid (Tentaculita) species ‘Spirorbis’ angulatus Hall, 1861. Journal of Paleontology 86:417-424.

 

Five-Year Anniversary Edition of Wooster’s Fossil of the Week: A tabulate coral from the Devonian of northwestern Ohio

January 1st, 2016

AuloporaDevonianSilicaShale010211This post of Wooster’s Fossil of the Week marks five years of this feature. If you’re counting, that is 260 entries, with never a week missed. To celebrate, I’m returning to the very first fossil in the series, a beautiful encrusting tabulate coral. The original entry is below, with some updates and added links.

This week’s fossil was collected by Brian Bade of Sullivan, Ohio, and donated to Wooster as part of my hederelloid project.  It is a beautiful specimen of the tabulate coral Aulopora encrusting a brachiopod valve from the Silica Shale (Middle Devonian — about 390 million years old) of northwestern Ohio.  [Update: I now know the species is A. microbuccinata Watkins, 1959.] Auloporid corals are characterized by an encrusting habit, a bifurcating growth pattern, and horn-shaped corallites (individual skeletal containers for the polyps).

What is especially nice about this specimen is that we are looking at a well preserved colony origin.  The corallite marked with the yellow “P” is the protocorallite — the first corallite from which all the others are derived.  You can see that two corallites bud out from the protocorallite 180° from each other.  These two corallites in turn each bud two corallites, but at about 160°.  This pattern continues as the colony develops (a process called astogeny).  The angles of budding begin to vary depending on local obstacles; they never again go below 160°.

The polyps inside the corallites are presumed to have been like other colonial coral polyps.  Each would have had tentacles surrounding a central opening, and all were connecting by soft tissue within the skeleton.  They likely fed on zooplankton in the surrounding seawater.  This type of coral went extinct in the Permian, roughly 260 million years ago.

Again, we thank our amateur geologist friends for such useful donations to the research and educational collections in the Geology Department at Wooster.

Later I began to add information about a notable paleontologist associated with the highlighted fossil. I especially wanted to put a face and brief biography with a name we may often see in our taxonomic pursuits but know little about. We can now add this German gentleman from a previous entry —
August_Goldfuss_1841Aulopora was first described in 1826 by Georg August Goldfuss (1782-1848), a German paleontologist and zoologist. (Goldfuß is the proper spelling, if I can use that fancy Germanic letter.) He earned a PhD from Erlangen in 1804 and later in 1818 assumed a position teaching zoology at the University of Bonn. With Count Georg zu Münster, he wrote Petrefacta Germaniae, an ambitious attempt to catalog all the invertebrate fossils of Germany (but only got through some of the mollusks). The 1841 portrait above is by Adolf Hohneck (1812-1879).

Since the first few entries I began to add a few critical references for the fossils and related stratigraphy. At first these were for me so that I could remember where I got the information used in the text. Later I noted that students and others were finding these entries online and using them as brief introductions to particular taxa. A few references made each entry a starting point for someone else’s paleontological explorations. Here are some added citations for Aulopora

References:

Fenton, M.A. 1937. Species of Aulopora from the Traverse and Hamilton Groups. American Midland Naturalist 18: 115-119.

Fenton, M.A. and Fenton, C.L. 1937. Aulopora: a form-genus of tabulate corals and bryozoans. American Midland Naturalist 18: 109-115.

Goldfuß, G.A. 1826-1844. Petrefacta Germaniae. Tam ea, quae in museo universitatis Regia Borussicae Fridericiae Wilhelmiae Rhenanae servantur, quam alia quaecunque in museis Hoeninghusiano Muensteriano aliisque extant, iconibus et descriptionibus illustrata = Abbildungen und Beschreibungen der Petrefacten Deutschlands und der angränzenden Länder, unter Mitwirkung von Georg Graf zu Münster, Düsseldorf.

Helm, C. 1999. Astogenese von Aulopora cf. enodis Klaamann 1966 (Visby-Mergel, Silur von Gotland). Paläontologische Zeitschrift 73 (3/4): 241–246. [Courtesy of Paul Taylor]

Scrutton, C.T. 1990. Ontogeny and astogeny in Aulopora and its significance, illustrated by a new non‐encrusting species from the Devonian of southwest England. Lethaia 23: 61-75.

Watkins, J.L. 1959. Middle Devonian auloporid corals from the Traverse Group of Michigan. Journal of Paleontology 33: 793-808.

Wooster’s Fossil of the Week: A fragmentary rostroconch from the Middle Devonian of Ohio

November 27th, 2015

1 Hippocardia 1Not all of our featured fossils are particularly beautiful, or even entire, but they are interesting in some way. Above is the broken cross-section of a rostroconch mollusk known as Hippocardia Brown, 1843. It was found somewhere in Ohio by the late Keith Maneese and kindly donated to the department by his widow Cameron Maneese. From its preservation and the kind of rock making up the matrix inside, we can tell that it almost certainly came from the Columbus Limestone (Middle Devonian, Eifelian).

In the top image it is apparent that this fossil has bilateral symmetry, a heart-shaped cross-section, and a ribbed calcitic shell. This is the dorsal view.
2 Hippocardia 2Flipping the specimen upside-down, we now have a view of the ventral portion. Again we see the ribs and bilateral symmetry.
3 Hippocardia side viewThis side view shows that the ribs extend from the dorsal to the ventral sides and are angled to the axis of the shell. That’s about all we can tell. (And this is the best specimen of a rostroconch we have! Thank you again, Cameron.)
4 CzechVirtualRostroThis diagram of a complete rostroconch (from the Czech Virtual Museum). This is a side view of a species that does not have the dorsal-ventral ribbing. The shell is superficially like that of a bivalve (clam), but the valves are fused together and their is a distinctive tube (rostrum) extending to the posterior. Much study and debate about the rostroconchs has at least confirmed that these are a class of mollusks separate from the bivalves. They lived semi-infaunally with the rostrum extending into the seawater to channel a flow of water into the body chamber for filter-feeding, much like infaunal bivalves today that have siphons. Rostroconchs and cephalopods appear to be sister groups, and some rostroconchs may have evolved into the scaphopods. Plenty of arguments to go around, though, on the evolution and diversification of mollusks
5 Thomas 1843 p 976 Thomas pl 8 fig 10 1843Captain Thomas Brown (1785-1862) named the genus Hippocardia in 1843. He was a Scottish naturalist who studied many topics, including mollusks. Above are the sections of his book The Elements of Fossil Conchology that describe and illustrate Hippocardia (considering it a bivalve). Captain Brown was born in Perth and went to school in Edinburgh. He joined the militia at 20, becoming a captain at 26. When he was transferred to Manchester, England, Brown acquired an interest in nature. He bought a flax mill after leaving the military, but it burned down while still uninsured. He thus turned to nature writing for support. He was became a Fellow of the Royal Society of Edinburgh in 1818, and in 1840 he was appointed curator of the Manchester Museum. He retained this position for the rest of his life. He was later a Fellow of the Linnean Society and a member, in classic 19th Century fashion, of several other groups, including the Wernerian, Kirwanian and Phrenological Societies. (I love the addition of phrenology to his interests!) The marine gastropod Zebina browniana d’Orbigny, 1842, was named after him. An interesting character, this Captain Brown, but I’ve been unable to find a single portrait of him.

References:

Brown, T. 1843. The elements of fossil conchology according to the arrangement of Lamarck; with the newly established genera of other authors. Houlston & Stoneman, London; 133 pages.

Hoare, R.D. 1989. Taxonomy and paleoecology of Devonian rostroconch mollusks from Ohio. Journal of Paleontology 63: 838-846.

Pojeta, J., Jr., Runnegar, B. 1976. The paleontology of rostroconch mollusks and the early history of the phylum Mollusca. United States Geological Survey Professional Paper 968: 1-88.

Pojeta, J., Jr., Runnegar, B., Morris, N.J. and Newell, N.D. 1972. Rostroconchia: a new class of bivalved mollusks. Science 177: 264-267.

Runnegar, B., Goodhart, C.B. and Yochelson, E.L. 1978. Origin and evolution of the Class Rostroconchia [and discussion]. Philosophical Transactions of the Royal Society B: Biological Sciences 284(1001): 319-333.

Wagner, P.J. 1997. Patterns of morphologic diversification among the Rostroconchia. Paleobiology 23: 115-150.

Wooster’s Fossil of the Week: A tall brachiopod from the Devonian of western Russia

November 20th, 2015

1 Ladogia Nalivkin, 1941In the summer of 2009 I had a field adventure in Russia. It was an extraordinary time. I learned considerable amounts of Russian geology and paleontology, of course, and was immersed in the Russian geological culture. Along the way I collected the above unusual brachiopod. We are looking at its posterior (where the articulating hinge is), with the ventral valve below and dorsal valve above.
2 Ladogia Nalivkin, 1941This is the anterior view of the same specimen showing the junction between the valves (the commissure). The brachiopod is Ladogia Nalivkin, 1941, a rhynchonellid from the Upper Devonian (Frasnian) of the Central Devonian Field somewhere along the Syas River in the Leningrad Oblast of western Russia. We can immediately see that this brachiopod is very tall for its kind, with a strongly defined fold (the top part of the “anticline” in the dorsal valve) and sulcus (the lower folded surface in the  ventral valve). Note that the sulcus has several encrusting organisms, including eroded microconchids.
3 Ladogia Nalivkin, 1941The side view shows the dramatic upward sweep of the dorsal valve and the fine radiating ornamentation. The tall fold was effective in separating the incoming water for filter-feeding from the outflow of filtered water, essentially functioning like a chimney. Many brachiopods have such a fold and sulcus, but few have a set of such amplitude.
4 Nalivkin, Dmitrii VasilevichLadogia was described by Dmitrii Vasil’evich Nalivkin (1889-1982) in 1941. Nalivkin was a Soviet paleontologist and geologist born in 1889 in St. Petersburg. He graduated from the Institute of Mines in Petrograd (the name was changed from St. Petersburg) in 1915. In 1917 he joined the Geological Commission of Russia, staying a member through its many changes for over six decades. In 1920 he became a professor at the Institute of Mines after, we presume, the political situations from the Great War, the Bolshevik Revolution and the Russian Civil War calmed down. He is notable for giving the first lecture series on facies theory in the USSR in 1921. After World War II he was chairman of the Turkmen section of the Academy of Sciences. In 1954 he was made chairman of the Interdepartmental Stratigraphic Committee of the Academy of Sciences of the USSR. In 1954 he was appointed chairman of the Interdepartmental Stratigraphic Committee of the Academy of Sciences of the USSR. Nalivkin specialized in stratigraphy and paleontology of the Paleozoic, especially the Devonian and Carboniferous. He is best known for his geological maps of the USSR, for which he received the Lenin Prize in 1957. Here’s a man who saw a lot of history in his time.

References:

Nalivkin, D.V. 1941. Brachiopods of the Main Devonian field. Akademii Nauk SSSR Trudy 1: 139-226.

Sokiran, E.V. 2002. Frasnian-Famennian extinction and recovery of rhynchonellid brachiopods from the East European Platform. Acta Palaeontologica Polonica 47: 339-354.

Zhuravlev, A.V., Sokiran, E.V., Evdokimova, I.O., Dorofeeva, L.A., Rusetskaya, G.A. and Malkowski, K. 2006. Faunal and facies changes at the Early-Middle Frasnian boundary in the north-western East European Platform. Acta Palaeontologica Polonica 51: 747-758.

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