Archive for January, 2015

Wooster’s Fossil of the Week: A stromatoporoid from the Silurian of Estonia

January 30th, 2015

Densastroma pexisumStromatoporoids are extinct sponges that formed thick, laminated skeletons of calcite. They can be very common in Silurian and Devonian carbonate units, sometimes forming extensive reefs. The stromatoporoid above is Densastroma pexisum (Yavorsky, 1929) collected from the Mustjala Member of the Jaani Formation (Silurian, Wenlock) exposed on Saaremaa Island, Estonia. It was part of Rob McConnell’s excellent Senior Independent Study he completed in 2010.
Densastroma pexisum sectionStromatoporoids are rather featureless lumps until you cut a section through them. Then you see their characteristic laminae of calcite. Looking very close you might also glimpse the tiny vertical pillars between the laminae. Identifying the species of stromatoporoid always involves a thin-section or acetate peel to discern the forms of the pillars and laminae.

In the upper left of the sectioned D. pexisum is an oval boring cut through the fabric of the stromatoporoid. This is likely the trace fossil Osprioneides kampto Beuck and Wisshak, 2008. This is the largest known Palaeozoic boring. It is relatively common in Silurian stromatoporoids of the Baltic region. Last year Olev Vinn, Mari-Ann Mõtus and I published a paper describing the same ichnospecies in large trepostome bryozoans from the Estonian Ordovician.
8 schematic drawing of Osprioneides kampto
This diagram of O. kampto is from Figure 8 of the Beuck et al. (2008) paper. The organism that made the boring was almost certainly a filter-feeding worm of some kind that gained a feeding advantage by placing itself high on a hard substrate.
Flügel in 7000 ts by Chris SchulbertDensastroma was originally named in 1958 by Erik Flügel (1934-2004). He combined the Latin densus with the Greek stroma, meaning “dense-layered”. (Yes, taxonomic purists will object to the mix of Latin and Greek in one name.) Flügel was a highly accomplished and diverse scientist who founded the Institute of Paleontology at the University of Erlangen-Nuremberg as well as the journal Facies. He is best known for his advocacy of detailed study of carbonate facies through petrography (“microfacies analysis“), developing a series of techniques and principles that I found very useful in my dissertation work. The above image is a fitting tribute to Erik Flügel made by Chris Schulbert. It is a portrait made of 7000 carbonate thin-sections!

References:

Beuck, L., Wisshak, M., Munnecke, A. and Freiwald, A. 2008. A giant boring in a Silurian stromatoporoid analysed by computer tomography. Acta Palaeontologica Polonica 53: 149-160.

Flügel, E. 1959. Die Gattung Actinostroma Nicholson und ihre Arten (Stromatoporoidea). Annalen des Naturhistorischen Museums in Wien 63: 90-273.

Freiwald, A. 2004. Erik Flügel: 1934–2004. Facies 50: 149-159.

Vinn, O., Wilson, M.A. and Mõtus, M.-A. 2014. The earliest giant Osprioneides borings from the Sandbian (Late Ordovician) of Estonia. PLoS ONE 9(6): e99455. doi:10.1371/journal.pone.0099455.

Three Days on Ice

January 25th, 2015

group

Dr. Lowell and a crew from the University of Cincinnati spent thee days with us on the ice at Browns Lake Bog. The objectives were to take a series of long cores from the ice platform at the bog and, in the big lake,  to take a short surface core that the Wooster Geomorphology class will study. In addition we installed a series of four nested monitoring wells in the sediments around the lake.coring_theoryThe coring crew taking the deep core – about 24 meters in two meters of water depth.

coring_sed_water

The sediment-water interface on TV – note the screen on the ice that helped guide the coring process to be sure the actual sediment-water interface was captured.

sed_water

Subsampling the upper core to be sure the modern sediments at the interface were in the bag.

coring_1

The ongoing coring.

probe1

Measuring dissolved oxygen, pH, TDS, ORP and Temperature along a depth profile.

 

instrument_wellMeasuring the same parameters in four sets of nested monitoring wells  – one deep, one shallow.

on_iceDrilling holes in the ice along  grid and measuring depth profiles in the big lake.

ice_holesOne of the ice hole teams.

probingThe mud probing team – not a glamorous job but necessary.

water_levelMeasuring the water levels in the well after bailing.

weather_stationThe weather station installed at the bog. 

well_prepDrilling a series of holes to act as a screen in the monitoring wells.

pumpingPumping the wells for isotope samples and installing a transducer to keep track of water levels.

shootingErika takes aim at the upper branches of a white oak – she will extract the water from these twigs and buds and measure their isotopic composition.

shavingPealing the twigs and bagging them up for transport.

our_coreTom recovering the surface core from the middle of Browns Lake – the big lake. Now the ball is in our court to do some analysis. Great thanks go out to the Core Boss and his crew.



Wooster’s Fossil of the Week: A predatory gastropod from the Pliocene of Cyprus

January 23rd, 2015

Naticarius millepunctatus Pliocene CyprusThis week we have another fossil from the Nicosia Formation (Pliocene) of the Mesaoria Plain in central Cyprus. It is again from a Keck Geology Consortium project in 1996 with Steve Dornbos (’97). This time, though, instead of our Coral Reef locality, our featured creature is from a sandy marl outcrop we called “Exploration”. We have above an aperture view of Naticarius millepunctatus Risso, 1826, a species still alive today and known as the “many-spotted moon shell”. It is a naticid gastropod, heir to a predatory tradition that strikes fear in the tiny hearts of bivalves.
Naticarius millepunctatus Pliocene Cyprus View 2Naticid gastropods, like our Naticarius, have a well-muscled foot that they use to essentially swim through loose sand to capture infaunal bivalves and other shelled prey. They then use their specialized radula to drill into the shell, kill the unfortunate animal, and then consume the soft goodies. Naticids leave distinct drill holes in the shells of their victims, as shown in a previous Fossil of the Week post. We found a few drilled bivalve shells with our Naticarius millepunctatus at the Exploration site.
André_Marie_Constant_DumérilNaticarius was named as a genus in 1806 by André Marie Constant Duméril (1774-1860). Duméril was another member of that marvelous group of French zoologists that lived through the French Revolution. He was a professor of anatomy, herpetology and ichthyology at the Muséum National d’Histoire Naturelle in Paris, corresponding and collaborating with such eminents as Georges Cuvier and Alexandre Brongniart. His most prominent work was Zoologie analytique, published in 1806. In this massive treatise he compiled descriptions of all the known genera of animals in an effort to sort them out in a repeatable way.
Dumeril KeyThis is a page from Duméril’s Zoologie analytique. We immediately recognize this as a binary taxonomic key, even if we can’t read the French. Starting from the left we make yes or no decisions about the anatomy of the animal we’re trying to identify, eventually ending on the right with a genus. (Naticarius is at number 10.)

André Marie Constant Duméril did prodigious work with reptiles as well, describing in detail 1393 “species” over nine volumes. (Oddly, in defiance of his fellow zoologists, he insisted that amphibians should be counted among the reptiles, thus the quotes around his number of “reptiles”.) Duméril also had major works on insects. His son, Auguste Duméril, was also a zoologist. As the elder Duméril retired, Auguste gradually took over his scientific projects.

References:

Cowper Reed, F.R. 1935. LII.—Notes on the Neogene Faunas of Cyprus.—III. The Pliocene Faunas. Journal of Natural History 16: 489-524.

Dornbos, S.Q. and Wilson, M.A. 1999. Paleoecology of a Pliocene coral reef in Cyprus: Recovery of a marine community from the Messinian Salinity Crisis. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 213: 103-118.

Duméril, C. 1806. Zoologie analytique, ou Méthode naturelle de classification des animaux, rendue plus facile à l’aide de tableaux synoptiques. Allais, Paris. 344 pp.

Tyler, C.L. and Schiffbauer, J.D. 2012. The fidelity of microstructural drilling predation traces to gastropod radula morphology: paleoecological applications. Palaios 27: 658–666.

Wooster’s Fossil of the Week: Another vermetid gastropod from the Pliocene of Cyprus

January 16th, 2015

Petaloconchus intortus (Lamarck, 1818)Why another one of those strange twisty gastropods from the Pliocene of Cyprus for our Fossil of the Week? Because this one fooled me for years. Above is a pair of images of a specimen of the vermetid gastropod Petaloconchus intortus (Lamarck, 1818) from the Nicosia Formation (Pliocene) of central Cyprus. It is encrusting a branch of the coral Cladocora. Ever since 1996 I’ve cataloged this and other such Cypriot specimens as serpulids, a type of polychaete worm that constructs adherent calcareous tubes like these. In fact, I placed on Wikipedia an image of the specimen below as a serpulid example.
Petaloconchus Cyprus Pliocene 585Last week an anonymous editor on Wikipedia changed the caption on my image from “serpulid worm tube” to “Petaloconchus“. I did some research and yes, he or she was correct. I’ve since remade the image and updated all the Wikipedia pages where it appeared. This is not the first time I’ve posted a fossil image online and been corrected, and I hope it’s not the last. Such feedback and criticism is a major advantage of online science, and I learn a great deal.

In my research on Petaloconchus, I found a delightful Journal of Paleontology paper by Stephen Jay Gould in which he defines a new subspecies of Petaloconchus sculpturatus and discusses the genus and its evolution in classic Gouldian ways (Gould, 1994). He, for example, found this quote by Myra Keen (1961, p. 183):

The Vermetidae (worm gastropods) probably hold a record among molluscs for the degree of confusion they have promoted, both in collections, and in the literature; for they have been misconstrued at every level from subspecies to phylum.

I’m happy to see I’m not the only one who has had trouble with vermetid gastropods. Even in Gould’s (1994, p. 1035) taxonomy of his new subspecies we see some of the issues with Petaloconchus:

Etymology.–alaminatus to recognize key feature of the absent internal laminae. The Linnean name is a paradox, as Petaloconchus means laminate shell (the supposed, but inadequate, definition of the genus), while the subspecific name alaminatus negates this characteristic feature. But who ever denied either nature’s complexity or evolution’s capacity to eliminate structures?

HCLeaPetaloconchus was named in 1843 by Henry Charles Lea (1825-1909), an American historian and political activist — an unexpected description of someone who named a snail. Lea came from a family deeply embedded in early American politics, and his father, Isaac Lea (1792-1886) was a prominent naturalist. Henry was clearly a prodigy in many endeavors. Note that his paper describing Petaloconchus and other fossils was completed when he was just 18 years old. In 1847, as a young man of 22, he suffered a mysterious nervous breakdown. During his long convalescence he read French medieval history, which turned his interests to the humanities. He eventually became a renowned historian of the Spanish Inquisition. (No one expects the Spanish Inquisition.)
LeaPetaloconchusOriginal image of Petaloconchus sculpturatus by Lea (1843).

Serpulids Cyprus PlioceneAbove are some real serpulid worm tubes from the Pliocene of Cyprus, although I’m open to corrections!

References:

Aguirre, J., Belaústegui, Z., Domènech, R., de Gibert, J.M., and Martinell, J. 2014. Snapshot of a lower Pliocene Dendropoma reef from Sant Onofre (Baix Ebre Basin, Tarragona, NE Spain). Palaeogeography, Palaeoclimatology, Palaeoecology 395: 9-20.

Bradley, E.S. 1931. Henry Charles Lea. A Biography. Philadelphia, University of Pennsylvania Press, 418 pages.

Carpenter P. 1857. First steps toward a monograph of the recent species of Petaloconchus, a genus of Vermetidae. Proceedings of the Zoological Society of London 24: 313-317.

Gould, S.J. 1994. Petaloconchus sculpturatus alaminatus, a new Pliocene subspecies of vermetid gastropods lacking its defining generic character, with comments on vermetid systematics in general. Journal of Paleontology 68: 1025-1036.

Keen, A.M. 1961. A proposed reclassification of the gastropod family Vermetidae. Bulletin of the British Museum (Natural History), Zoology, 7:183-213.

Lea, H.C. 1843. Descriptions of some new fossil shells, from the Tertiary of Petersburg, Virginia. Transactions of the American Philosophical Society 9: 229-274. [The volume was actually published in 1846.]

Wooster’s Fossil of the Week: A worm-like gastropod from the Pliocene of Cyprus

January 9th, 2015

Vermetus Pliocene Cyprus aperture viewThis week we continue with fossils from the Nicosia Formation (Pliocene) of the Mesaoria Plain in central Cyprus. These fossils are from a Keck Geology Consortium project in 1996 with Steve Dornbos (’97). Above we have one of the most distinctive forms at the Coral Reef locality: the gastropod Vermetus Daudin, 1800. It doesn’t look much like a snail with its irregular, twisty tube of a shell, but the animal within was very snaily indeed.
Vermetus Pliocene CyprusVermetus and its relatives are still alive today, so we know a lot about their biology. They are sessile benthic, cemented, filter-feeding marine organisms, meaning they are stationary on some hard oceanic substrate sorting out organic materials from the water. They gather their food in one of two ways: capturing plankton in their gills (much like most bivalves) or making a net of mucus threads that is gathered occasionally with their radulae, with the food passed to the mouth. They have separate sexes. The male broadcasts sperm into the water column. The female catches some of this sperm in her mucus feeding net. She then broods the fertilized eggs in her mantle cavity. Vermetids are common enough that they are even used today to determine tectonic movements in the Mediterranean (Sivan et al., 2010).

The genus Vermetus was named in 1800 by François Marie Daudin (1774-1804). Daudin was a French zoologist with a hard, short but very productive life. He contracted a disease in childhood that left his legs paralyzed, and thereafter devoted his time to natural history. He started (but did not complete) one of the first modern books on ornithology, combining description with Linnean taxonomy. His work on amphibians and reptiles was epic, finishing eight volumes that described 517 species. In all his research he was helped by his wife Adèle, who drew his hundreds of illustrations, including those below. She died of tuberculosis in 1804, and he died soon after only 29 years old. They both lived in poverty in Paris during the dislocations of the French Revolution.
Screen Shot 2014-12-31There are no portraits of François Marie Daudin, so the best I can do in his memory is reproduce some of the illustrations of modern Vermetus (drawn by Adèle Daudin) in his 1800 book titled (in translation) “Collection of memories and notes on new or little-known species of molluscs, worms and zoophytes”. Here’s to our memory of the Daudins.

References:

Cowper Reed, F.R. 1935. LII.—Notes on the Neogene Faunas of Cyprus.—III. The Pliocene Faunas. Journal of Natural History 16: 489-524.

Daudin, F.M. 1800. Recueil de Mémoires et de Notes sur des espèces inédites ou peu connues de Mollusques, de Vers et de Zoophytes, orné de gravures. Chez Fuchs, Libraire, rue des Mathurins. Treuttel et Wurtz, quai Voltaire; 50 pp.

Dornbos, S.Q. and Wilson, M.A. 1999. Paleoecology of a Pliocene coral reef in Cyprus: Recovery of a marine community from the Messinian Salinity Crisis. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 213: 103-118.

Sivan, D., Schattner, U., Morhange, C. and Boaretto, E. 2010. What can a sessile mollusk tell about neotectonics? Earth and Planetary Science Letters 296: 451-458.

Wooster’s Fossil of the Week: An encrusted scallop from the Pliocene of Cyprus

January 2nd, 2015

Chlamys Pliocene CyprusOne of the very best paleontological sites I had the pleasure of collecting was on the hot Mesaoria Plain near the center of the island of Cyprus. It was the summer of 1996 and Steve Dornbos (’97) and I were pursuing research as part of a Keck Geology Consortium project. We were exploring the Nicosia Formation, a Pliocene series of thick marls with occasional fossiliferous beds. We stumbled across a remarkable fossil coral reef preserved in a hillside. This deposit and its fossils became the basis of Steve’s Independent Study project and a paper (Dornbos and Wilson, 1999). One of the most prominent (and beautiful) fossil types we found was the pectinid clam Chlamys. The specimen above fell into our category of “Chlamys sp. 1″ because we couldn’t further identify it. Note that it has near the hinge on the left a juvenile Chlamys attached to it, as well as a circular serpulid tube near the top center. The details of the shell are very well preserved.
Chlamys interior Pliocene CyprusThis is the interior view of the same specimen of Chlamys. Visible at the hinge is the isodont dentition and, extending to the left, the distinctive auricle of the genus. On the right side of the hinge is a bit of the young Chlamys.

This species of Chlamys likely nestled between the branches of the coral in our reef, opening its valves to filter-feed. It was not a swimmer like some of its thin-valved, symmetrical pectinid cousins living in the same reef.
Peter Friedrich RödingChlamys was named in 1798 by Peter Friedrich Röding (1767–1846), a German naturalist who lived in Hamburg. He chose the name from the Greek chlamys (χλαμύς) because he thought it looked like the folds of this ancient Greek cloak. In 1798 Röding published a sale catalogue of mollusk shells (fossil and modern). The descriptions of specimens were minimal, but he had long lists of new taxonomic names, making him the official author of dozens of molluscan genera. Strangely, Röding didn’t put his name on the catalogue. He was only officially recognized as its author by a ruling of the International Commission on Zoological Nomenclature in 1956, thus ensuring the perpetuation of his name in our taxonomic system.

We’ll see more gorgeous fossils from the Pliocene of Cyprus in the coming weeks.

Wooster’s Fossil of the Week feature is four years old today. There have been 208 posts in this series, starting with the first posted on January 2, 2011. I hope there are many more to come!

References:

Dornbos, S.Q. and Wilson, M.A. 1999. Paleoecology of a Pliocene coral reef in Cyprus: Recovery of a marine community from the Messinian Salinity Crisis. Neues Jahrbuch für Geologie und Paläontologie, Abhandlungen 213: 103-118.

Röding, P.F. 1798. Museum Boltenianum sive catalogus cimeliorum e tribus regnis naturæ quæ olim collegerat Joa. Fried Bolten, M.D. p. d. per XL. annos proto physicus Hamburgensis. Pars secunda continens conchylia sive testacea univalvia, bivalvia & multivalvia. – pp. [1-3], [1-8], 1-199. Hamburgi, Trapp.