Wooster’s Fossils of the Week: A scleractinian coral and its tube-dwelling symbionts (Middle Jurassic of Israel)

April 20th, 2014

MatmorCoral010114aI have a weakness for the beautiful scleractinian corals of the Matmor Formation (Middle Jurassic, Callovian-Oxfordian) of southern Israel. This particular specimen is Microsolena aff. M. sadeki from locality C/W-367 in Hamakhtesh Hagadol, southern Israel. (The “aff.” in the name means “affinities with”. It is a way of saying this looks like a particular species, but we’re not quite sure.) This is a place we’ve now had ten Wooster Team Israel expeditions, the latest of which was last summer. The corals are a prominent part of the very diverse fossil fauna there. Note in the above side view of the specimen the star-shaped corallites (which held individual polyps) each with radiating septa. In the middle of the view you can see a narrow tube covered by coral skeleton. (More on this below.)
MatmorCoral010114bThis is a top view of the coral. It has a generally flat base and an upper surface with extended knobs. Usually this particular species is flat across the top as well as the base, giving it a platter shape as in this previous Fossil of the Week.
MatmorCoral010114cFlip the coral over and we see how it is preserved. The skeleton was originally made of the mineral aragonite, which dissolved after the death and burial of the colony. The resulting void was filled with stable calcite, preserving even fine details of the septa (see below). This delicate preservation, though, is only of the exterior of the skeleton. The interior is coarsely crystalline calcite with no trace of internal coral structures. This preservation, then, is properly called a cast, not true replacement.
MatmorCoral010114tubeThese scleractinian corals had many symbionts (organisms that lived with them). Among them were tube-dwelling worms, probably polychaetes, that spread across the surface. We know this happened while the coral was alive because, as seen above, the septa sometimes grew over the tubes. The tubes themselves are here preserved in three dimensions because they are originally calcitic and did not dissolve after death and burial.

We have much to learn about these gorgeous Jurassic fossil corals of Israel. They are virtually unstudied and offer a great opportunity for comparing them to the global Jurassic coral world.


Martin-Garin, B., Lathuilière, B. and Geister, J. 2012. The shifting biogeography of reef corals during the Oxfordian (Late Jurassic). A climatic control?. Palaeogeography, Palaeoclimatology, Palaeoecology 366: 136-153.

Pandey, D.K., Ahmad, F. and Fürsich, F.T. 2000. Middle Jurassic scleractinian corals from northwestern Jordan. Beringeria 27: 3-29.

Reolid, M., Molina, J.M., Löser, H., Navarro, V. and Ruiz-Ortiz, P.A. 2009. Coral biostromes of the Middle Jurassic from the Subbetic (Betic Cordillera, southern Spain): Facies, coral taxonomy, taphonomy, and palaeoecology. Facies 55: 575-593.

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.

Wilson, M.A., Feldman, H.R. and Krivicich, E.B. 2010. Bioerosion in an equatorial Middle Jurassic coral-sponge reef community (Callovian, Matmor Formation, southern Israel). Palaeogeography, Palaeoclimatology, Palaeoecology 289: 93-101.

Our camel friends in the Negev

April 18th, 2014

camel head 041814MITZPE RAMON, ISRAEL–It is a problematic relationship between camels and me. My first experience with a camel out here was watching one eat my lunch, bag and all, when I foolishly left it in the shade of the vehicle while I measured a section. My students and I have been dissuaded more than once from visiting a particular outcrop by aggressive, bellowing camels standing their ground and looked very, very big and toothy. I was thus a bit hesitant when Yoav just walked up to this beauty on our way to the center of Makhtesh Gadol. I followed and did just fine within touching distance. This is a female (hence the lack of attitude) and a pregnant one at that. She is part of a small herd owned by a Bedouin family that may or may not have an arrangement to graze animals in this nature reserve. She eased my camel anxieties.

camel bed fossils 041814After our encounter I realized that camels actually play a role in our work. This is one of our most productive fossils sites (“GPS 055″). It is an exposure of a marl in subunit 51 in the Matmor Formation. This is also a camel resting spot. They love the soft sediment, probably as a break from the rocky soil elsewhere. We thus find such dry camel wallows often in our explorations of the Matmor. By stirring up the marl, the camels unearth fossils that would otherwise lay hidden.

Random Echinoderm bits 041814Here is a random assortment of crinoid and echinoid bits found in this camel haven. If we ignore the poop and flies, and avoid the angry males, these camels have done us a scientific favor!

Wooster’s Fossil of the Week: An unusual scleractinian coral from the Upper Cretaceous of Israel

April 13th, 2014

Aspidiscus 041114aOriginally this was going to be a mystery fossil for a crowd-sourced identification while I’m here in Israel doing fieldwork, but through the wonders of the internet I finally found a match for the strange fossil above: it is the scleractinian coral Aspidiscus König, 1825 (Family Latomeandridae) Yoav Avni and I found several specimens in the lower third of the En Yorqe’am Formation (Upper Cretaceous, Cenomanian) in the Negev of southern Israel. I had never seen anything like it before.

The view above is of the upper surface of this discoidal fossil. There are several short and seemingly random ridges, which I learned later are called monticules in this genus. Each monticule has a series of septa, or thin vertical partitions. This was a compound coral, meaning it had multiple polyps on its surface, presumably each sitting on a monticule.
Aspidiscus 041114bThis is a reverse view of the En Yorqe’am variety of Aspidiscus. The pits appear to be molds of a gastropod on which the young coral must have recruited. It then grew centripetally, making a fine series of growth lines across a soft sediment.
Aspidiscus cristatus diagramThis diagram from Pandey et al. (2011) is a diagram of Aspidiscus cristatus found in the Cenomanian of Sinai, not too far from here. (This species is also found in Algeria, Tunisia, Spain, Greece, and Afghanistan — all in the Cenomanian.) Note that the center of A. cristatus has two large crossing monticules and the Israeli specimen does not. This is why I’m keeping it in open nomenclature — it doesn’t appear to be the same species. A. cristatus is found in the middle to early late Cenomanian; the En Yorqe’am specimen seems so far to be only in the early Cenomanian. This may mean the Israeli version is an older species. Both clearly liked living in marly shallow marine sediments.
Aspidiscus symbiontsHere’s the bonus: look at the round holes in the upper surfaces of these two specimens. These are caused by symbionts of some kind that lived within the growing coral. You can see best in the specimen on the right how the coral grew around the symbionts, producing a kind of tube. Nice.

Sorry for the lower quality of images this week. I’m photographing the fossils as best I can with a bedside lamp, a tiny tripod, and a shirt for background.


Avnimelech, M. 1947. A new species of Aspidiscus from the Middle Cretaceous of Sinai and remarks on this genus in general. Eclogae geologicae Helvetiae 40: 294-298.

Gill, G.A. and Lafuste, J.G. 1987. Structure, repartition et signification paleogeographique d’Aspidiscus, hexacoralliaire cenomanien de la Tethys. Bulletin de la Societe Geologique de France 3: 921-934.

Pandey, D.K., Fürsich, F.T., Gameil, M. and Ayoub-Hannaa, W.S. 2011. Aspidiscus cristatus (Lamarck) from the Cenomanian sediments of Wadi Quseib, east Sinai, Egypt. Journal of the Paleontological Society of India 56: 29-37.

Field trip to the lesser known makhteshim at Har ‘Arif

April 10th, 2014

Har 'Arif 041014MITZPE RAMON, ISRAEL–We’ve talked a lot about makhteshim in this blog, with so much of our geological work located in Hamakhtesh Hagadol and Makhtesh Ramon. A makhtesh is essentially a breached anticline, usually with a single drainage running from it. There are two small makhteshim at Har ‘Arif that are rarely seen because it takes some effort to get to them (major dirt road challenges and a significant hike) and they are in a military area that has very limited access. The Geological Survey of Israel got permission to run a field trip up to the top of Har ‘Arif today, and I was privileged to go along. The image above is of Har ‘Arif (the peak in the middle) looking up through the axis of the larger of the two makhteshim here. Its elevation is 956 meters, and it is the ninth highest peak in Israel. It is noted for its craggy, angular top, which is unlike most other Negev mountains with their rounded or flattened outlines.

Geologist camp 041014We began the day with an early departure from Mitzpe Ramon to meet most of the team camped out near Har ‘Arif. Note as the sun rises the crew has jackets on. It was an unseasonably cool start.

Hike begins 041014The hike begins. The goal is the very tippy-top of the mountain, so lots of work ahead in this beautiful setting.

Group outcrop 041014As with any geology field trip, we stopped occasionally for lectures on the outcrops. These lectures were in Hebrew so I was a spectator. It’s funny that after awhile I could pick out what the major arguments were from the tone of voice and various hand gestures. Several participants (especially Yoav) kindly interpreted for me afterwards. We are here examining an outcrop of the Middle Triassic Raaf Formation. This is a unit low in the Triassic that is not seen elsewhere in Israel.

Ripples Gyrochorte 041014These are ripplemarks in a fine sandstone of the Gevanim Formation (Middle Triassic, Anisian). Note the trace fossils that are convex epirelief, meaning they are positive relief on the surface of the bed. They are of the ichnogenus Gyrochorte, an old friend of mine from the Jurassic of Utah.

View west Har 'Arif 041014We reached the top of the mountain after an arduous climb. The coordinates are N 30.42591°, E 34.734°. (Really, google map these numbers. I worked hard for them!) This is the view to the east looking over the Negev all the way to the mountains of Jordan. One limb of the smaller makhtesh is below.

Har 'Arif Makhtesh 041014Here is the larger of the two makhteshim, looking west from the top of Har ‘Arif. It is gorgeous. All the rocks making the floor and walls are Triassic. The ridge line in the far distance is the border with Egypt.

I’ll have more later on the abundant flowers of the Har ‘Arif area. Right now it is a much-anticipated bedtime for me!

A mission in the Cretaceous of southern Israel

April 9th, 2014

Wadi Mishar viewMITZPE RAMON, ISRAEL–Today Yoav and I set out to solve a mapping dilemma concerning the boundaries of the Upper Cretaceous (Cenomanian) En Yorqe’am Formation in the Negev and, eventually, the Judean Desert to the north. It involved a bumpy ride deep into some of the most beautiful areas of the country, and it produced all sorts of delicious paleontological and sedimentological mysteries. I’ll talk more about this trip in later entires. Since it was 12 hours and I get up at 4:00 a.m. tomorrow, this is a truncated entry!

The setting is the stratigraphy of the En Yorqe’am and its bounding units: the Hevyon Formation below and the Zafit Formation above. Our job was to examine the contacts between these units and help come up with consistent definitions that can be used throughout the region. Right now there is considerable fuzziness as to where each formation begins and ends. Above is a labeled image showing the magnificent outcrop in Wadi Mishar (taken from our studied section at N 30.54899°, E 34.98843°).

Oysters En Yorqeam 040914In the process of sharpening the definition of the En Yorqe’am, we found some magnificent fossils. There are many paleontological and sedimentological projects possible in this unit. Oysters dominate the En Yorqe’am in most places we visited. Above is a close view of one outcrop (at N 30.65788°, E 35.08764°; Nahal Neqarot) showing that the sediment is almost entirely oyster. The shells are often beautifully bored, but strangely there are virtually no encrusters.

Stromatoporoid En Yorqeam 040914To our surprise, we found these large roundish objects that look very much like stromatoporoids (at N 30.65788°, E 35.08764°). The lack visible mamelons (or corallites, for that matter), but internally they appear to show the typical laminations and pillars of these calcareous sponges. I’ve never seen them in the Cretaceous before, which is at the end of their range. I could be wrong and these fossils are odd altered corals. Only cutting and polishing will tell.

Terebratulids En Yorqeam 040914Also unexpected was the prevalence of brachiopods in parts of the En Yorqe’am (at N 30.65788°, E 35.08764°). These are articulated terebratulid brachiopods. They look very Jurassic in their appearance, but here they are in the Upper Cretaceous.

I’m looking forward to working with Wooster students on these outcrops next year! More on the En Yorqe’am later this week.

Cretaceous echinoderms are today’s stars

April 8th, 2014

Zichor 040814MITZPE RAMON, ISRAEL–There’s a joke in the title, in case you didn’t notice! I was on my own for my second day of fieldwork in southern Israel. I revisited yesterday’s outcrops of the Upper Cretaceous (Coniacian) Zichor Formation, taking more time to plot out future section-measuring and fossil-collecting sites for students. I was also able to spend a lot of classic nose-on-the-ground time sorting out the fossils.

The outcrop above is about the top half of the Zichor Formation in this area (N 30.30587°, E 34.96543°). Note the cemented limestones near the top and the soft marls in the foreground. Both have plenty of fossils, but you can imagine which is easier to collect from.

Filograna? 040814One mystery of this unit is at the very top of the section in one of the last bedding planes. There are extensive amounts of a twisty worm-tube called Filograna (or at least something close to it). You can see it in the above image. I was told earlier it was a “mat”, but it appears to be instead broken fragments of tube accumulations scattered about. Strange critter, this worm.Echinoid tests 040814The marls of the Zichor have an impressive echinoderm content. Since they have calcitic tests, they are very well preserved. Above are five heart urchins showing their classic pentameral symmetry.

Echinoid test plates 040814Here are fragments of a cidaroid echinoid test. In the middle of each plate is a circle with a boss extending outwards. Spines were attached to these, one of which is included in the image. I hope on our later expedition we can find whole specimens. Students are always up for these discovery challenges.

Asteroid ray oral 040814This was a first find for me: an asteroid (sea star) ray fragment. I don’t think I’ve ever found a sea star fossil before. We are looking above at the oral side where tube feet would have extended.

Asteroid ray aboral 040814This is the other side of the fragment — the aboral side. Beyond being cool, I’m afraid there is not a lot of significance for this fossil unless I can identify it further. Sea stars are famous for living in all sorts of marine environments, from the intertidal to deep trenches.

Some future Wooster students are going to have a good time with this unit sorting out the paleontological, sedimentological and stratigraphic contexts and then comparing this tropical fauna to the better known assemblages in the temperate north.

A Triassic afternoon in southern Israel

April 8th, 2014

Mitzpe Ramon distant view 040814MITZPE RAMON, ISRAEL–This afternoon I walked through the spectacular Middle Triassic sections in Wadi Gevanim on the southern side of the Makhtesh Ramon structure. I will be on a fantastic trip this Thursday to a little-visited Triassic section farther south, so I wanted to refresh my memory of these units. The above image is looking north from Wadi Gevanim to Mitzpe Ramon just visible on the cliff edge of the makhtesh. (What a setting, eh?)

Nautiloids Ammonites 040814I found myself almost completely repeating an entry from last year on Wadi Gevanim (which had the added bonus of students in it). Today I gathered some impressive fossil cephalopods from the Saharonim Formation (Middle Triassic, Anisian-Ladinian) for a group photograph. I note only now that one of the nautiloids above appears last year as well! From the upper left going clockwise: nautiloid, ammonite, nautiloid, ammonite. All are internal molds (the outer shell has been removed).

Nautiloid 040814That upper left nautiloid is worth a closer look. The mold has been split down the middle showing the septa (internal walls dividing the chambers) and an impressive “beaded” siphuncle (connecting tube) running the length of the conch (shell).

Terebratulids 040814Finally, here is a handful of the common terebratulid brachiopods from the Saharonim. Speaking of which, have I mentioned the species Menathyris wilsoni from the Saharonim? You certainly must meet Menathyris wilsoni!

A Wooster Geologist is finally warm enough

April 7th, 2014

Yoav Zichor 040714MITZPE RAMON, ISRAEL–When I left Wooster on Saturday morning it was 34°F and overcast. It was sunny and an astonishing 84°F when I arrived in Tel Aviv on Sunday afternoon. That additional 50 degrees felt very good indeed after a winter of polar vortices and late-March snowstorms. I’m now based in the Ramon Suites Hotel in Mitzpe Ramon near the lip of the spectacular Makhtesh Ramon (N 30.60638°, E 34.80128°).

I’m back in Israel as part of my research leave from the College. This is my chance to explore new outcrops and ideas with my Israeli colleagues to prepare for the next generation of Independent Study students — and, of course, to do plenty of science for its own sake. I miss my students, though, for their companionship, sharp eyes, challenging questions, and navigation abilities (i.e., telling me when I’ve taken a wrong turn). This is how the leave system works so that we always have fresh projects with interesting and testable hypotheses. This is my 11th field season in Israel.

Today I met my long-time friend Yoav Avni of the Geological Survey of Israel, along with Zeev Lewy, a paleontologist retired from the Survey, to look at a fossiliferous unit Zeev discovered over two decades ago south of Mitzpe Ramon. We looked at the thickest section of the Zichor Formation (Late Cretaceous, Coniacian) to sort out a remarkably diverse set of silicified (silica-replaced) fossils associated with a mat of worm tubes (possibly of the genus Filograna). The top image shows the upper portion of the Zichor, with Yoav for scale (location: N 30.30587°, E 34.96543°). The image below is a view of the bedding plane with most (but not all) of the silicified fossils colored dark brown.

Zichor silcified fossils 040714One of the cool things about this layer is that the fossils are silicified, which is rare in this part of the Cretaceous section. Another is that aragonitic mollusks are preserved in this way (especially gastropods and bivalves), along with their calcitic cousins (like oysters and pectenids). The Filograna-like worm tube layer itself is fascinating since no one knows much about the paleoecology of this group, and we suspect it may have some significant evidence about the paleoenvironment encoded in its spaghetti-like appearance.

Zichor Menuha contact 040714The top of the Zichor meets the bottom of the Menuha Formation chalks (Late Cretaceous, Santonian). In this view, the yellow and brown Zichor is in the foreground and middle ground, with the whitish Menuha in the background.

Zichor Menuha close 040714Yoav and I visited the boundary between the Zichor (darker unit on the left) and Menuha (lighter on the right) to assess their relationship (N 30.30212°, E 34.95909°). At outcrops 30 km to the north this boundary is marked by a deep unconformity (eroded interval) and a layer of encrusted and bored cobbles. Here the boundary is flat and nearly continuous. The layer of silicified shells is just a few centimeters below the unconformity. This may not be by chance — units immediately below unconformities often have silicified zones.

Some of you may remember these unit names from previous expeditions. Micah Risacher (’11) worked on the Zichor Formation and its fossils in the Makhtesh Ramon area, and Andrew Retzler (’11) did his Independent Study research on the Menuha. We can now build on their excellent work as we develop additional outcrops and new questions.

Ordnance 040714Finally, it wouldn’t be the Negev if there wasn’t some ordnance on the outcrop. Can you tell what kind of bomb is shown above? The clues are in its current condition!

Wooster’s Fossil of the Week: A brontothere jaw fragment (Miocene of South Dakota)

April 6th, 2014

Titanotherium proutiiThis fossil has been sitting in a glass case outside my office door for nearly three decades. Only this year — in the desire to find more Fossils of the Week — did I bother to open the cabinet and take it out for a looksie. On the reverse was a 19th century label: “Titanotherium proutii, Badlands, SD”. That started me on a complicated journey through the literature to see just what sort of creature bore these magnificent molars, as well as the history of its discovery.
Titanotherium proutii occlusalIn this occlusal (meaning the biting surface) view you can see in the beautiful flowing lines of the hard (dark) and softer (light) enamel that there are some serious cracks repaired with a dodgy yellowish glue. The specimen is very fragile — that glue has probably been holding it together for well over a century. These are classic plant-eating teeth for both cutting and grinding leaves, roots and small branches.
TitanotheriumThe animal represented here is a titanothere, a large extinct mammal common in what would become the Badlands of South Dakota during the Paleogene. Above is a recreation of a relative of our species: Megacerops (Titanotherium) robustum. (The artist who drew this illustration in 1912 was Robert Bruce Horsfall, 1869-1948.) The titanotheres, now better known as brontotheres, were roughly the size and shape of rhinoceroses, but were actually more closely related to horses. They had elephant-like feet, inwardly-curved skull caps, and impressive horns on the nose.

I usually delight in tracking down taxonomic histories (the technical history of scientific names), but Titanotherium proutii has defeated me. The history of this taxon is convoluted beyond recovery — a sad tale of mistakes, misplaced fossils, specimens given multiple names, and over-zealous “splitting” of taxa. In other words, typical middle 19th century vertebrate paleontology. Mader (1998) says that Titanotherium Leidy 1853 (or 1852?) is a nomen dubium or “doubtful name”. Even the species, which later became Palaeotherium proutii, is nomen dubium. The names are simply worthless to science. I have been unable to figure out what the accepted name for our fossil now is.
Joseph_LeidyJoseph Leidy (1823-1891) named Titanotherium and (maybe) T. proutii (there is dispute as to who named it first). Leidy was a well known American biologist and paleontologist who taught first at the University of Pennsylvania and then Swarthmore College. He described and named the first nearly-complete dinosaur skeleton, Hadrosaurus foulkii. (It was found in the Cretaceous of New Jersey and he named it in 1858.) Leidy was also an early supporter of Charles Darwin and his the new theory of evolution, early enough for this to be an unpopular position. Edward Drinker Cope was one of his students, which forever places him at the beginning of the famous “Bone Wars” between Cope and Othniel Charles Marsh, which raged from 1877 to 1892. That epic conflict actually began in the New Jersey marl pits where Leidy’s hadrosaur was found. Leidy thus leaves us with a mixed legacy of discoveries, innovations and insights mixed with errors and folly. Just the sort of character we would expect on the frontier of a new science in a new country.
Leidy1Leidy’s 1853 (Plate XVI) figure of a jaw fragment of “Titanotherium proutii“.


Leidy, J. 1853. The ancient fauna of Nebraska: or, a description of remains of extinct Mammalia and Chelonia, from the Mauvaises Terres of Nebraska. Smithsonian contributions to knowledge, vol. 6. Washington, Smithsonian Institution.

Mader, B.J. 1998. Brontotheriidae. In: C.M. Janis, K.M. Scott, and L.L. Jacobs (eds.), Evolution of Tertiary Mammals of North America 1: 525-536.

Mihlbachler, M.C., Lucas, S.G. and Emry, R.J. 2004. The holotype specimen of Menodus giganteus, and the “insoluble” problem of Chadronian brontothere taxonomy. Paleogene Mammals. New Mexico Museum of Natural History and Science Bulletin 26: 129-135.

Warren, L. 1998. Joseph Leidy: the last man who knew everything. Yale University Press, New Haven; 303 pages.

Wooster’s Fossil of the Week: Thoroughly encrusted brachiopod from the Upper Ordovician of Indiana

March 30th, 2014

1 Rafinesquina ponderosa (Hall) ventralLast week was an intensely bored Upper Ordovician bryozoan, so it seems only fair to have a thoroughly encrusted Upper Ordovician brachiopod next. The above is, although you would hardly know it, the ventral valve exterior of a common strophomenid Rafinesquina ponderosa from the Whitewater Formation exposed just south of Richmond, Indiana (locality C/W-148). I collected it earlier this month on a trip with Coleman Fitch (’15).
2 Rafinesquina ponderosa (Hall) dorsalThis is the other side of the specimen. We are looking at the dorsal valve exterior. Enough of the brachiopod shows through the encrusters that we can identify it. Note that both valves are in place, so we say this brachiopod is articulated. Usually after death brachiopod valves become disarticulated, so the articulation here may indicate that the organism had been quickly buried. This brachiopod is concavo-convex, meaning that the exterior of the dorsal valve is concave and the exterior of the ventral valve is convex.
3 Protaraea 032314Returning to the ventral valve, this is a close-up of the encruster that takes up its entire exterior surface. It is the colonial heliolitid coral Protaraea richmondensis Foerste, 1909. (Note the species name and that it was collected just outside Richmond, Indiana.) This thin coral is a common encruster in the Upper Ordovician. Usually it is a smaller patch on a shell. This is the most developed I’ve seen the species. The holes, called corallites, held the individual polyps.
4 Bryo on Protaraea 032314The encrusting coral has an encruster on top of it. This is a trepostome bryozoan, which you can identify by the tiny little holes (zooecia) that held the individuals (zooids). The patch of coral it is occupying must have been dead when the bryozoan larva landed and began to bud.
5 Trepostome 032314Now we’re returning to the concave dorsal valve with its very different set of encrusters. This is a close-up of another kind of trepostome bryozoan, this one with protruding bumps called monticules. They may have functioned as “exhalant current chimneys”, meaning that they may have helped channel feeding currents away from the surface after they passed through the tentacular lophophores of the bryozoan zooids. For our purposes, this is a feature that distinguishes this bryozoan species from the one on the ventral valve.
6 Cuffeyella 032314There is a third, very different bryozoan on the dorsal valve. This blobby, ramifying form is a well-developed specimen of Cuffeyella arachnoidea (Hall, 1847). It is again a common encruster in the Upper Ordovician, but not usually so thick.
7 Cuffeyella on hinge 032314If we look closely at the hinge of the brachiopod on the dorsal side, we can see a much smaller C. arachnoidea spreading on the ventral valve.
8 Encrusted edge 032314Finally, this is a side view of the brachiopod with the ventral valve above and the dorsal valve below. We’re looking at the junction of the articulated valves, the commissure. For the entire extent of the commissure, the encrusting coral grows to the edge of the ventral valve and no further. This is a strong indication that the brachiopod was alive when the coral was growing on it. The brachiopod needed to keep that margin clear for its own feeding.

The paleoecological implications here are that the coral was alive at the same time as the brachiopod. This means that the convex exterior surface of the ventral valve was upwards for the living brachiopod. The concave exterior surface of the dorsal valve faced downwards. The coral and bryozoan encrusting the top of the living brachiopod were exposed to the open sea; the bryozoans encrusting the undersurface of the living brachiopod were encrusting a cryptic space. We are thus likely seeing the living relationships between the encrusters and the brachiopod — this encrustation took place during the life of the brachiopod.

Further, this demonstrates that this concavo-convex strophomenid brachiopod was living with the convex side up. This has been a controversy for decades in the rarefied world of brachiopod paleoecology. This tiny bit of evidence, combined with some thorough recent studies (see Dattilo et al., 2009; Plotnick et al., 2013), strengthens the case for a convex-up orientation. Back when I was a student these would be fighting words!


Alexander, R.R. and Scharpf, C.D. 1990. Epizoans on Late Ordovician brachiopods from southeastern Indiana. Historical Biology 4: 179-202.

Dattilo, B.F., Meyer, D.L., Dewing, K. and Gaynor, M.R. 2009. Escape traces associated with Rafinesquina alternata, an Upper Ordovician strophomenid brachiopod from the Cincinnati Arch Region. Palaios 24: 578-590.

Foerste, A.F. 1909. Preliminary notes on Cincinnatian fossils. Denison University, Scientific Laboratories, Bulletin 14: 208-231.

Mõtus, M.-A. and Zaika, Y. 2012. The oldest heliolitids from the early Katian of the East Baltic region. GFF 134: 225-234.

Ospanova, N.K. 2010. Remarks on the classification system of the Heliolitida. Palaeoworld 19: 268–277.

Plotnick, R.E., Dattilo, B.F., Piquard, D., Bauer, J. and Corrie, J. 2013. The orientation of strophomenid brachiopods on soft substrates. Journal of Paleontology 87: 818-825.

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