Archive for November, 2013

Wooster’s Fossil of the Week: A crinoid calyx from the Lower Carboniferous of Iowa

November 24th, 2013

Macrocrinus verneuilianus (Shumard, 1855) 585In honor of Echinoderm Week for my Invertebrate Paleontology course, we have a beautiful crinoid calyx (or crown, or just “head”) on a slab from the Burlington Limestone (Lower Carboniferous, Osagean) found near Burlington, Iowa. I inherited this fossil when I arrived at Wooster, so I have no idea who collected it or when. The handwritten number is similar to those on many of our 19th century specimens. The sharp features of the specimen have been a bit dulled by a preparation technique that probably involved abrasives.

The crinoid is Macrocrinus verneuilianus (Shumard, 1855) of the Order Monobathrida. It is unusual in that it is preserved with its filter-feeding arms intact, along with a magnificent anal tube (see closer view below).
Macrocrinus anal chimney 585The anal tube, sometimes called an anal chimney, is just what you guessed it would be — an anus at the end of a long pipe of calcitic plates. Its primary purpose was all about hygiene. The tube allowed waste products to be whisked away far from the mouth of the crinoid, which was at the base of the arms. Some researchers suggest that the long tube served another function as well: it may have helped stabilize and direct the filter-feeding fan of outstretched arms in a stiff current, something like the tail of an airplane or a panel on a weather vane.

Macrocrinus verneuilianus (Shumard, 1855) diagramFigure of Macrocrinus verneuilianus (9) from “Paleontology of Missouri” (1884) by Charles Rollin Keyes. That long anal tube is not exaggerated!
Shumard585Benjamin Franklin Shumard (1820-1869) named Macrocrinus verneuilianus in 1855. As you might have deduced from his name, Shumard was a Pennsylvanian, having been born in Lancaster. He received his bachelor’s degree from Miami University in Oxford, Ohio, and then later earned an MD in Louisville, Kentucky, in 1843. As a young doctor in Kentucky, he began to collect fossils as a hobby. After just three years of medicine, he gave it up to pursue a career as a geologist. (Those Kentucky fossils must have been particularly fine!) By 1848 he was on geological surveys for Minnesota, Wisconsin and Iowa, and in 1850 he went on a geological survey expedition to Oregon. (Imagine that trip in 1850.) In 1853 he became the paleontologist in the Missouri Geological Survey. In 1858 he left Missouri to begin the first Geological Survey in Texas. The Civil War must have caused him considerable pain, since he was a Pennsylvanian in Texas. He moved to St. Louis and renewed his medical career in 1861. In 1869, he decided to move south to New Orleans for health reasons. The steamship he took burned to the waterline one evening north of Vicksburg. He was safely rescued, but contracted pneumonia in the process. He returned quickly to St. Louis and there died at 49 years of age. At the time of his death Shumard was president of the St. Louis Academy of Science and a member of the Geological Societies of London, France, and Vienna, and he was also a member of the academies of science in Philadelphia, Cincinnati, and New Orleans. No doubt we would have had much more scientific accomplishment from this young paleontologist had he lived longer.

References:

Ausich, W.I. 1999. Lower Mississippian Burlington Limestone along the Mississippi River Valley in Iowa, Illinois, and Missouri, USA, p. 139-144. In: H. Hess, W.I. Ausich, C.E. Brett and M.J. Simms (eds.), Fossil Crinoids, Cambridge University Press.

Ausich, W.I. and Kammer, T.W. 2010. Generic concepts in the Batocrinidae Wachsmuth and Springer, 1881 (Class Crinoidea). Journal of Paleontology 84: 32-50.

Lane, N.G. 1963. Two new Mississippian camerate (Batocrinidae) crinoid genera. Journal of Paleontology 37: 691-702.

Shumard, B.F. 1855. Description of new species of organic remains. Missouri Geological Survey 2:185–208.

Wooster’s Fossil of the Week: A long scleractinian coral from the Middle Jurassic of Israel

November 17th, 2013

Enallhelia_370_Callovian_Israel_585Just one image for this week’s fossil, but we make up for the numbers in image length! The above fossil with the alternating “saw teeth” is the scleractinian coral Enallhelia d’Orbigny, 1849. It is a rare component of the diverse coral fauna found in the Matmor Formation (Callovian-Oxfordian) in southern Israel. I collected this particular specimen (from locality C/W-370 in Hamakhtesh Hagadol, for the record) during this past summer’s expedition to the Negev. It is preserved remarkably well considering that its original aragonite skeleton has been completely calcitized.

Enallhelia is in the Family Stylinidae, also named by French naturalist Alcide Charles Victor Marie Dessalines d’Orbigny. (Love that name; he was briefly profiled in a previous entry.) There are many species in the genus (at least two dozen), but I can’t figure out which this one is. I’ll need a coral expert because half of the available species look pretty much the same to me. Enallhelia is a dendroid coral, meaning its corallum has tree-like branches, only one of which we see here. Each branch has alternating corallites on each side, which in life would have held the individual tentacular polyps. Each corallite has radial symmetry, not the usual hexameral symmetry as seen in most scleractinians. The genus ranges from the Jurassic into the Cretaceous and is cosmopolitan. Enallhelia is especially well known from Europe, but that may be just a collector effect.

What I like about Enallhelia is that it can be an excellent paleoenvironmental marker. Leinfelder and Nose (1997) show that it is most often found in “marly coral meadows” near storm wavebase on carbonate platforms. This means it is in shallow but quiet waters well within the photic zone most of the time, but may be occasionally disturbed by storm wave currents. This is an accurate description of most of the depositional environment of the Matmor Formation.

References:

Hudson, R.G.S. 1958. The upper Jurassic faunas of southern Israel. Geological Magazine 95: 415-425.

Leinfelder, R.R. and Nose, M. 1997. Upper Jurassic coral communities within siliciclastic settings (Lusitanian Basin, Portugal): Implications for symbiotic and nutrient strategies. Proceedings of the 8th International Coral Reef Symposium 2: 1755-1760.

Olivier, N., Martin-Garin, B., Colombié, C., Cornée, J.-J., Giraud, F., Schnyder, J., Kabbachi, B. and Ezaidi, K. 2012. Ecological succession evidence in an Upper Jurassic coral reef system (Izwarn section, High Atlas, Morocco). Geobios 45: 555-572.

Wooster’s Fossil of the Week: A colonial scleractinian coral from the Pliocene of Cyprus

November 10th, 2013

Cladocora_585This week’s fossil is another from the collection made in 1996 on a Keck Geology Consortium expedition to Cyprus with Steve Dornbos as a Wooster student. Steve and I found a spectacular undescribed coral reef in the Nicosia Formation (Pliocene) near the village of Meniko (N 35° 5.767′, E 33° 8.925′). Finding a reef was a surprise because the unit is mostly quartz silt, which is not a sediment you usually associate with coral reefs. It was an advantage, though, because the silt was poorly lithified and could be easily removed from the fossils. The significance of this reef was that it represents the early recovery of marine faunas following the Messinian Salinity Crisis and the later refilling of the Mediterranean basin (the Zanclean Flood). Steve and I published our observations and analyses of this reef community in 1999.

The coral is a species of the genus Cladocora Ehrenberg, 1834. This genus, a member of the Family Caryophylliidae, ranges from the Late Cretaceous to today, so it is a hardy group. This may be because it is unusually diverse in its habits, ranging from the shallow subtidal down to at least 480 meters, and including both zooxanthellate (containing symbiotic photosynthesizing organisms called zooxanthellae) and azooxanthellate (with no such symbionts) species. Since our fossils lived in shallow water, they were almost certainly zooxanthellate.

(Courtesy of Wikimedia Commons user Esculapio)

(Courtesy of Wikimedia Commons user Esculapio)

Cladocora is still found today in the Mediterranean (see the above Cladocora caespitosa). Like all zooxanthellate scleractinian corals, these shallow species of Cladocora obtain their nutrition from the byproducts of their photosynthetic symbionts and a diet of small animals (mostly arthropods and larvae) they collect with their tentacles. These tentacles are lined with “stinging cells” called nematocysts.
CladocoraSpondylus_585Our Pliocene Cladocora formed the framework of a reef at least six meters high and 50 meters wide. It had many shelled organisms living entwined in the branches of the coral, like the bivalve Spondylus pictured above. You can see the corallites (individual tubes) embedded in the shell.
EhrenbergChristianGottfried_585Christian Gottfried Ehrenberg (1795-1876) named the genus Cladocora from specimens in the Red Sea. He was a German naturalist and explorer who is often credited with founding the field of micropaleontology (the study of microfossils such as foraminiferans, ostracodes and diatoms). He earned an M.D. at the University of Berlin and remained on the university staff for his entire career. He was no homebody, though, traveling as a scientist throughout the Mediterranean and Middle East, Central Asia and Siberia. (His first expedition to the Middle East was an adventure, as you can read at the link.) He was the first to prove that fungi reproduce via spores, to describe the anatomy of corals, and to identify plankton as the source for marine phosphorescence. Ehrenberg was also the first to discover microfossils in rocks, noting that some rocks (like chalk) are made almost entirely of them. His best known books include Reisen in Aegypten, Libyen, Nubien und Dongola (1828; “Travels in Egypt, Libya, Nubia and Dongola”) and Die Infusionsthierchen als volkommene Organismen (1838; “The Infusoria as Complete Organisms”). That last concept (“volkommene Organismen” or “complete organisms”) was his idea that even the smallest organisms had all the working organs of the largest. That one didn’t go so well!

References:

Cowper Reed, F.R. 1935. Notes on the Neogene faunas of Cyprus, III: the Pliocene faunas. Annual Magazine of Natural History 10 (95): 489-524.

Cowper Reed, F.R. 1940. Some additional Pliocene fossils from Cyprus. Annual Magazine of Natural History 11 (6): 293-297.

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.

Citizen scientist to the rescue (in more ways than one)

November 9th, 2013

StephLizzie110913NEW LONDON, OHIO–The Wooster paleontologists spent a pleasant afternoon with our favorite amateur fossil collector Brian Bade. Brian has been mentioned in this blog previously for the many important fossils he has found and donated. He is a spectacular citizen scientist with a deep love (some would say obsession) with fossils of all kinds. He has a tremendous collection of fossils from the region and elsewhere carefully cataloged as to formations and localities. He knows what specimens may have scientific importance, and he has always been most generous with his time and fossils.

Today Steph Bosch (’14), Lizzie Reinthal (’14) and I visited Brian to examine specimens he recently collected from the Waldron Shale (Silurian) exposed in the St. Paul Stone Quarry in St. Paul, Indiana. My colleagues and I need to examine Silurian microconchids from North America and, sure enough, Brian came to the rescue with his collections and eagle eyes. Not only did he have his cleaned and sorted Waldron material laid out for us, he also had segregated specimens that had encrusting microconchids on them. The fossils were fantastic. Check out this webpage to get an idea of the paleontological diversity at this site.

Brian also brought out other trays and boxes of fossils from the Silurian and Early Devonian that had encrusters. Lizzie and Steph proved adept at picking out the tiny microconchids with their bare, young eyes as I struggled with my usual handlens. (This was the typical situation during our fieldwork in Israel this summer as well.) We accumulated several excellent specimens for later study under a Scanning Electron Microscope. Brian once again came through with critical fossils collected with all the right information for scientific analysis.

And the other rescue by Brian? You can see the situation in the image below. After all the driving I did in exotic places this summer, I managed to burrow into deep mud in Brian’s front yard. My little car was completely mired. (Note the smirking students in the background getting ready to tweet photos.) Brian has a tractor, fortunately enough, and a long chain. I left behind two deep trenches in his grass, and a little bit of my pride.
CarStuck110913

Wooster’s Fossils of the Week: Very common orthocerid nautiloids from the Siluro-Devonian of Morocco

November 3rd, 2013

Nautiloids585_092313If you’ve been to a rock shop, or even googled “fossil”, you’ve seen these beautiful and ubiquitous objects. They are polished sections through a nautiloid known as “Orthoceras“. We put quotes around the genus name because with these views it is nearly impossible to identify the actual genus, so “Orthoceras” becomes the go-to term for unknown orthoconic (straight) nautiloids. We also do not know exactly where in Morocco these fossils come from, but chances are they were dug out of the Orthoceras Limestone (Siluro-Devonian) exposed near Erfoud in the Ziz Valley near the edge of the Sahara Desert. They are easily excavated, take a nice polish, and look good from almost any angle of cut. People bring these to me often to ask about their origin, so let’s do a Fossil of the Week about the critters.

These fossil nautiloids consisted in life of a long, straight conical shell with internal chambers pierced by a long tube. The shells were originally made of aragonite, but almost all have been replaced and recrystallized with calcite. A squid-like animal produced the shell. Most of its body was in the large body chamber at the open end of the cone. They were effective nektic (swimming) predators during the Paleozoic Era around the world. In some places (like Morocco) nautiloids were so common that their dead shells carpeted shallow seafloors. Nautilus is a living descendant.
SingleNautiloid092313 annotatedIn this closer cross-sectional view of a Moroccan “Orthoceras“, we can identify the critical parts. A = a chamber (or camera); B = the siphuncle (tube running through the center of the shell); C = a septum that divides one chamber from another; D = an orthochoanitic (straight) septal neck of shell that runs briefly along the siphuncle. The white to gray material is crystalline (“sparry”) calcite that filled the empty shell after death and burial.

By the way, you can buy “Orthoceras healing stones“. A quote from that site: “Fossils are believed to increase life span, reduce toxins, anxiety, stress, balance the emotions, make one more confident. Containing supernatural and physical healing powers. They promote a sense of pride and success in business. Healers use fossils to enhance telepathy and stimulate the mind. Traditionally, fossils have been used to aid in  reducing tiredness, fatigue, digestive disorders, and rheumatism.” No wonder paleontologists are always the very image of health and wealth!
BRUGIEREThe genus Orthoceras was named in 1789 by the French zoologist (and physician) Jean Guillaume Bruguière (1749–1798). The only image I could find of him is the small one above. Bruguière earned a medical degree from the University of Montpellier in 1770, but like many aspiring naturalists, he never practiced. He traveled very widely for an 18th Century scientist, usually to pursue living and fossil mollusks on various expeditions. That he was a Republican in revolutionary France probably saved his head, but he lost his income in the turmoil. Most of his descriptions of fossil taxa appeared in print decades after he died on a voyage back from Persia. Of all his taxonomic contributions, the genus Orthoceras is the most widely known.

References:

Histon, K. 2012. Paleoenvironmental and temporal significance of variably colored Paleozoic orthoconic nautiloid cephalopod accumulations. Palaeogeography, Palaeoclimatology, Palaeoecology 367–368: 193–208.

Kröger B. 2008. Nautiloids before and during the origin of ammonoids in a Siluro-Devonian section in the Tafilalt, Anti-Atlas, Morocco. Special Papers in Palaeontology 79, 110 pp.

Lubeseder, S. 2008. Palaeozoic low-oxygen, high-latitude carbonates: Silurian and Lower Devonian nautiloid and scyphocrinoid limestones of the Anti-Atlas (Morocco). Palaeogeography, Palaeoclimatology, Palaeoecology 264: 195-209.