A dusty but successful start on field work in southern Israel

MITZPE RAMON, ISRAEL–Melissa Torma, our friend Yoav Avni (Geological Survey of Israel), and I just ended a productive first day in the field. The two of them are shown above in classic paleontological poses. They are collecting fossils from Subunit 51 of the Matmor Formation (Middle Jurassic) in Hamakhtesh Hagadol in the northern Negev. We found excellent crinoid stems and calyx plates, brachiopods, corals, sponges, echinoid spines, serpulid worms, clams, and oysters.The day was very windy but seasonably cool.

You might be wondering why the sky in the above photograph is not the usual bright blue for this region? It is because the air is filled with dust blown off the Sahara Desert to the eastern Mediterranean countries (see NASA image below from 2011). This is a common occurrence here in the spring when a storm system is on its way. In the course of a year, every square kilometer in Israel receives 30-60 tons of this dust. The storm will bring rain to northern Israel tomorrow and Wednesday, but it is very unlikely to break the drought here in the southern dessert.

Shown below is a curious fossil Yoav found at our new site in the Matmor Formation we’ve called (creatively) “halfway”. It is a crinoid stem with a pair of skeletal galls, each with several holes. It appears some organisms infected the living crinoid, which then responded by growing skeletal tissue around the offending critters. Eventually the walled-in organisms drilled their way out, leaving the holes. This is what it looks like, anyway. Feel free to speculate!

I’ve placed a slightly different view of the fossil below to show that these are not encrusters but rather echinoderm skeletal material.

We had a great day despite the pervasive dust and wind gusts. It feels so good to get back to a desert again.

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Wooster Geologists in southern Israel for Spring Break fieldwork

It’s a low-light, iPad photo, but at least it shows Wooster geology junior Melissa Torma enjoying a fine meal in the Hotel Ramon of Mitzpe Ramon, deep in the Negev of Israel. We arrived here this afternoon after a 22-hour journey from Ohio. The hardest part for me was enduring the 10.5-hour flight and then making a quick transition to driving through heavy Tel Aviv traffic on our southern journey. It all went well, though, and we are safely in our rooms getting ready for our first day of fieldwork tomorrow.

Melissa and I are here to measure sections and collect specimens for her Senior Independent Study project involving the description and paleoecological analysis of a Jurassic brachiopod-crinoid community in the Matmor Formation of Hamakhtesh Hagadol. I’ve collected these crinoids before here, and now Bill Ausich of Ohio State University and I are describing them as a new species of Apiocrinites. Melissa and I want to find more specimens (we hope more complete specimens) of this crinoid and place them in the context of the entire marine community they inhabited. Our partner in this effort is again our friend Yoav Avni of the Geological Survey of Israel.

When we left the USA yesterday there was a series of violent actions between terrorists in Gaza and the Israel Defense Forces. You may hear about rockets from Gaza striking southern Israel, but they are far from us. We see no evidence of the fighting here. We are very safe in the vastness of the Negev Highlands.

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Wooster’s Fossil of the Week: An ichthyosaur vertebra (Middle-Late Jurassic of Wyoming)

It’s only half a bone, but the above is one of my favorite fossils. This is a vertebra of an ichthyosaur, identifiable by its figure-8 cross-section. It is from the Sundance Formation (Middle-Late Jurassic) of Natrona County, Wyoming … and is the first ichthyosaur bone I found. There is not a lot to go on with a single bone fragment like this, but luckily for me only one ichthyosaur has been found in the Sundance: Ophthalmosaurus natans (Marsh, 1879). (“Ophthalmosaurus” is sometimes spelled “Opthalmosaurus” in the literature, and the inconsistency maddens me.)

Finding the ichthyosaur bones on June 23, 2008. Image courtesy of my friend Paul D. Taylor at the Natural History Museum.
Ophthalmosaurus reconstruction (along with some nice ammonites) from Wikipedia. Image Creator: Dmitry Bogdanov.

Ichthyosaurs were magnificent animals that were contemporaries of the dinosaurs. Ichthyosaur means “fish-lizard”, but they were neither fish nor lizards but a unique type of marine reptile. Their streamlined bodies are excellent examples of convergent evolution with the unrelated dolphins and sharks.

Ophthalmosaurus is best known for its very large eyes, up to 10 cm in diameter, with protective bones called sclerotic rings. They probably used these eyes to see in deep, murky waters, or they hunted prey at night.
This view of vertebrae cut in half is from the first paper to describe ichthyosaurs: Home (1814). You can see the distinctive figure-8 shape, known professionally as “cupped vertebrae”. The ichthyosaur specimen Home presented was found by the famous Mary Anning and her brother Joseph. Home thought the animal was some kind of odd fish. Home and the Annings had much more than just these vertebrae, but I like the symmetry of their big discovery and my little one.
Sir Everard Home, 1st Baronet FRS, 1756-1832, was a British physician fascinated by anatomy. Besides the ichthyosaur, he is also known for the earliest anatomical work on the platypus.

References:

Home, E. 1814. Some account of the fossil remains of an animal more nearly allied to fishes than any of the other classes of animals. Philosophical Transactions of the Royal Society of London 104: 571–577.

Huene, F. von. 1922. Die Ichthyosaurier des Lias und ihre Zusammenhage: Berlin (Gebr. Bonrntraeger), 114pp.

Maisch, M.W. 2010. Phylogeny, systematics, and origin of the Ichthyosauria – the state of the art. Palaeodiversity 3: 151–214.

Marsh, O.C. 1879. A new order of extinct reptiles (Sauranodontia), from the Jurassic Formation of the Rocky Mountains. American Journal of Science, 3rd series, 17: 85-86.

O’Keefe, F.R., Street, H.P., Cavigelli, J.P., Socha, J.J. and O’Keefe, R.D. 2009. A plesiosaur containing an ichthyosaur embryo as stomach contents from the Sundance Formation of the Bighorn Basin, Wyoming. Journal of Vertebrate Paleontology 29: 1306–1310.

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On Being A Female Geologist

Happy International Women’s Day! I’ve been reflecting on what it means to be a female geology professor ever since the Wooster Alumni Magazine featured an article on Annie Irish, the first woman on Wooster’s faculty. Her portrait graces the foyer of the Timken Science Library, so I see Annie every Research Friday, yet I’ve never really thought about her role (or mine) in Wooster’s legacy.

The portrait of Annie Irish that presides over the Timken Science Library entry.

Annie clearly made an impact on the Wooster community and was much loved on campus. According to an 1897 Wooster Alumni Bulletin, her portrait was a gift given by alumni (Annie’s former students) to Hoover Cottage. Women’s cottages were one of the many ways that Annie advocated for female students. She envisioned campus housing that would help female students feel comfortable and develop networks. Annie’s legacy is carried on by the Women’s Advisory Board, established in 1892, which provides financial support for international and female students.

Supporting the education of women is a longstanding and widespread issue, particularly in the Science, Technology, Engineering, and Mathematics (STEM) fields. Every two years, the National Science Foundation (NSF) compiles a report on the status of Women, Minorities, and Persons with Disabilities in Science and Engineering. They’ve found that women are participating in the physical sciences and mathematics at relatively low levels. Although the percentage of physical science degrees awarded to women has grown since the early 1990s, women are still earning those degrees at relatively low levels compared to men.

Percentage of degrees awarded to women in the physical sciences and mathematics between 1990 and 2008. Source: Women, Minorities, and Persons with Disabilities in Science and Engineering: 2011.

The participation of women in the sciences can be broadened by funding agencies that make it a strategic goal at all academic levels. The NSF ADVANCE program, for example, supports projects that encourage women to pursue academia as a career. Some ADVANCE projects, like MU-ADVANCE at my undergraduate alma mater, make changes at the institutional level. Other ADVANCE projects support women by establishing and maintaining partnerships. The Earth Science Women’s Network is just one example of an ADVANCE project that provides peer-mentoring opportunities for female scientists. At the undergraduate and graduate levels, the Clare Boothe Luce Program supports women who are pursuing degrees in science, engineering, and math. Just this year, Wooster had the good fortune to designate four female science majors as Clare Boothe Luce Research Scholars, who will be provided funding to conduct research and travel to conferences.

Funding isn’t the only strategy for supporting female scientists; women need strong role models and effective mentoring. The Association for Women Geoscientists (AWG), for example, is one organization that not only awards scholarships, but also sponsors outreach activities and facilitates mentoring. I didn’t discover AWG until graduate school, which is where I first encountered female geology professors (with the exception of one fabulous female geoscientist who ran an REU that changed my life). This isn’t to say that my undergraduate professors were poor mentors; I just wonder how my perspectives (and those of my classmates) would have changed if we had had a female role model.

Fortunately, strong female geoscientists are somewhat easier to find today. In fact, half of the Wooster Geology Department consists of female faculty members, and this is where I might find my legacy at Wooster. I can encourage women to pursue the geosciences by sharing my experiences, connecting them to resources, and helping them realize their potential. A quick glance at the list of recent College and Departmental award recipients reveals a talented group of female geology majors:

Tricia - One of the four Clare Boothe Luce Scholars from The College of Wooster.

Lindsey - Co-winner of the 2012 Charles B. Moke Prize for showing the greatest improving during her college career.

Sarah - Co-winner of the 2012 Charles B. Moke Prize for showing the greatest improvement during her college career.

Anna - 2012 Karl VerSteeg Prize winner, awarded to the major who has the highest general standing in the middle of the junior year.

Congratulations to these talented young geologists! You are examples of promising young women who enhance the image of female geoscientists everywhere.

UPDATED (11:55 PM): Looking for other posts on female geologists? Try  Looking for Detachment’s 2010 post on Cornelia Clermont Cameron or Scientific American’s post on Geologizing Women. Thanks to @sfoxx for the links!

References:

Dixon, M. 2012. Reconstructing Annie. Wooster 126: 28-31.

Scovel, S.F., and Compton, E., eds. 1897. Alumni Roundtable. The Post-Graduate and Wooster Quarterly XI (4): 339-354.

 

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Wooster’s Fossil of the Week: an encrusted nautiloid (Upper Ordovician of Kentucky)

Two fossils this week in our series. The large segmented cone is a bisected nautiloid cephalopod from the Upper Ordovician of northern Kentucky. The original shell (made of the mineral aragonite) has been dissolved away, leaving the sediment that filled it (making an internal mold). Encrusting the nautiloid mold is a grayish, bumpy layer called Dermatostroma Parks, 1910.

The nautiloid belongs to a subclass of cephalopods still with us today. This Ordovician fossil is in the Family Orthoceratidae McCoy, 1844, which existed from the Early Ordovician (490 million years ago) through the Triassic (230 million years ago). It had a straight, conical shell with walls inside separating chambers (camerae) and a central tube (the siphuncle) connecting them. They were swimming (nektic) predators that could control their buoyancy through a mix of gases and liquids in the camerae mediated by the siphuncle.
Reconstruction of an orthocerid nautiloid by Nobu Tamura.

The fact that the mold is encrusted is interesting in itself. The encrusting organism (Dermatostroma) had to grow over the mold after the aragonitic shell had dissolved and the sediment cemented up. This must have happened on the seafloor, not long after the death and partial burial of the nautiloid. Such rapid dissolution and cementation is characteristic of Calcite Sea conditions, a situation we don’t have in today’s oceans.

Dermatostroma is a genus of stromatoporoid sponge named and described by William Arthur Parks in 1910. It is always very thin and often distinguished by a field of tiny bumps (meaning this species is likely Dermatostroma papillatum). It was a filter-feeding organism, and its fossils are often overlooked.

William Arthur Parks (1868-1936) was a Canadian paleontologist from Hamilton, Ontario. He was a professor at the University of Toronto for most of his career. In 1927, he was elected President of the Paleontological Society. Parks did detailed work on the almost microscopic details of fossil stromatoporoid sponges, and then made a dramatic field change and became an accomplished dinosaur paleontologist. The small ornithopod dinosaur Parksosaurus is named after him.

References:

Palmer, T.J., Hudson, J.D. and Wilson, M.A. 1988. Palaeoecological evidence for early aragonite dissolution in ancient calcite seas. Nature 335 (6193): 809–810.

Parks, W.A. 1910. Ordovician stromatoporoids of America. University of Toronto Studies, Geology Series 7, 52 pp.

Sweet, W.C. 1964. Nautiloidea — Orthocerida, in Treatise on Invertebrate Paleontology. Part K. Mollusca 3, Geological Society of America, and University of Kansas Press, New York, New York and Lawrence, Kansas.

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A Wooster Geologist … on TV?

The irony of me appearing for brief moments as a commentator on last night’s episode of Ancient Aliens (“Aliens and Mega-Disasters“) is that I teach a course at Wooster entitled “Nonsense! And Why It’s So Popular“. One of our favorite topics is the American obsession with extraterrestrials, ancient and otherwise. Now I’m actually embedded forever in an episode of this popular pseudoscientific show, and getting there was so much fun.

My stint as a TV talking head was not the result of a national talent search for a suave and photogenic geologist — I’d have no chance at that! — but instead through our Director of Public Information, John Finn. He convinced me to let him nominate me for the show after the producer asked if we had any geologists who might want to give it a go.

The producer of this episode of Ancient Aliens, who works for Prometheus Entertainment, called me in December 2011 and outlined what she wanted from the “scientific talent”. She was very friendly, honest and frank about the programming, assuring me from the start that I wouldn’t “lose my science card” by participating. She wanted scientists to help frame the scientific issues, naturally, and then she would slot in the “other talent” to present the extraterrestrial angles. She knew very well from my webpages, CV and continual reminders that I am, shall we say politely, not convinced by the evidence for the ancient alien hypothesis. She kept her word, too, and made certain that I and the other scientists in the show did not appear to be lending any support to these speculations.

On January 3rd a film crew arrived at the College early in the morning and set up an interview studio in our second-floor teaching laboratory (Scovel 205). They knew just what to do and where because the producer had asked me earlier to send her photographs of likely places for filming. The crew consisted of four men: a lighting expert, a sound man, a guy who helped set up equipment and communicate with headquarters, and a field producer in charge. Watching these men work was fascinating. They love their craft and spent hours making sure everything looked and sounded right. They were so much fun to work with, and they told many stories of other “shoots” they had been on for dozens of other shows. They were all very informed on scientific issues, and they asked me lot of questions just out of curiosity.

In the one photo (above) I snapped of the set up process, you can see some of the preparations in the lab, including the many lights, filters and cables. Eventually that whole wall was covered with black-out sheets. On the tables are trays of fossils for demonstrations and extra footage that may prove useful someday (for what they called “B-roll”).

The field producer made sure I signed the various contracts necessary for this work. “Scientific talent” does not get paid on these shows, in case you were wondering, and the exclusive rights to the footage are given to the production company “forever” and “throughout the universe”. After the interview studio was constructed in our lab and the camera set up, the film team sent test shots to Hollywood for their approval. Once it came (and it came quickly), we started the interview.

I had been sent a list of questions about a week before the shoot, so I knew the broad outlines of what was coming. The field producer was so good at essentially having a conversation with me about the topics that all my rehearsed answers quickly dropped away. There is some danger in that as a scientist, of course, when you find yourself just glibly talking for hours without notes, but I certainly understand why they don’t just want to record one of our tedious lectures. We just chatted, with my interviewer occasionally reminding me to repeat the question at the start of my answers. He had many of his own ideas and insights, so the process was quite engaging. It is hard to believe now, but at the time I had quickly forgotten about the microphones, camera and hot lights. I suppose this is how reality television works.

The interviews, which lasted all day, were recorded on actual film. At the end of the process they bundled up all the film for an overnight express mailing to Hollywood. The film crew deconstructed the interview set-up and returned the lab to exactly its former condition, aided by iPhone photos they made of the room beforehand. You would never know they were there.

Last night the results appeared on the History Channel. In the screen-grab above (I tried hard to snap a non-dorky pose but was not successful!) you can see the carefully placed microscope in the background, the backlit door, the posters to fill blank spaces on the walls, and the subtly-lit bookshelves. It really does look like professional television. The episode itself is available here, at least for a short time.

Through this adventure I learned a lot about the profession of filming and the integrity of the production crews, and I now have some insights into how an episode of a program like this is constructed. Again, I must emphasize that this whole aliens-came-to-Earth scenario has zero scientific support (and really, alien bases in active volcanoes?). I like to believe, though, that even through this unlikely medium some people out there are receiving the occasional veiled hints of real science.

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Accretionary Wedge #43: Fun with Chemographic Projections

This month’s Accretionary Wedge calls for posts on our favorite geological illustrations. Some of my personal favorites are drawn by Dr. Kurt Hollocher from Union College. His collection of hand-drawn thin sections is enough to make any petrologist drool.

One of Dr. Hollocher’s most whimsical illustrations involves the AFM chemographic projection. Chemographic projections are often used in metamorphic petrology to plot complex compositions on two-dimensional triangular diagrams. A popular chemographic projection for metapelites is the AFM diagram, which represents Al2O3, FeO, and MgO at its corners. In his series of AFM diagrams, Dr. Hollocher has a little fun with the retrograde garnet-out reaction.

Retrograde chloritoid-in reaction. Courtesy of Dr. Kurt Hollocher.

Poor garnet. Courtesy of Dr. Kurt Hollocher.

Garnet is doomed! Courtesy of Dr. Kurt Hollocher.

Goodbye garnet. Courtesy of Dr. Kurt Hollocher.

The progressive garnet-out reaction. Courtesy of Dr. Kurt Hollocher.

Almost gone. Courtesy Dr. Kurt Hollocher.

Hello chlorite pesudomorph after garnet! Courtesy of Dr. Kurt Hollocher.

Special thanks to Dr. Kurt Hollocher for the fantastic illustrations and the permission to use them in our Accretionary Wedge Post.

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Wooster’s Fossil of the Week: A holey brachiopod (Lower Cretaceous of southeastern Spain)

This striking and unusual brachiopod is Pygites diphyoides (d’Orbigny, 1847) from Hauterivian (Lower Cretaceous) of Cehegin, Murcia, Spain. Wooster acquired it through a recent generous exchange of brachiopods with Mr. Clive Champion in England. I had heard about this brachiopod genus with a hole through its shell, but never before actually seen one. Thank you very much, Clive.

Pygites diphyoides is a terebratulid brachiopod, an order that is still in existence today. It is commonly called a “keyhole brachiopod” because of the perforation running vertically through the shell. It attached to the substrate with a pedicle (a stem-like device protruding through the pointy end of the shell). Pygites and its relatives appear to have been adapted deep sea, poorly oxygenated conditions, although they are found in shallower facies as well (Dieni and Middlemiss, 1981; Kazmer, 1993; Michalik, 1996).
In this reconstructed cross-section of Pygites (from Michalik, 1996, fig. 4) we can see how the central perforation may have helped with the flow of nutrient-bearing currents through the shell. (Although I must admit to being a bit baffled by the arrows!)
Pygites diphyoides was orginally described as “Terebratula diphyoides” in 1847 by the famous French naturalist Alcide Charles Victor Marie Dessalines d’Orbigny (1802-1857). He was a prolific scientist in many fields, including paleontology, general geology, zoology, archaeology and anthropology. D’Orbigny was a native Frenchman who grew up on the Atlantic coast of his country. He was especially fascinated with marine organisms, even giving the name (in 1826) to a group of protists we now know as “foraminiferans“. He was a proponent of the ideas of his countryman and esteemed zoologist Georges Cuvier during what were exciting times in the development of zoology and paleontology. He was an astonishingly productive scientist, with dozens of reports, papers and books to his credit, and he accumulated a spectacular collection of fossils and zoological specimens. D’Orbigny combined geology and paleontology in very useful ways, becoming one of the earliest biostratigraphers. As a Cuvier disciple, though, he believed the rock record showed a series of successive catastrophes and new creations, so he rejected the developing ideas of evolution during his lifetime (Taylor, 2002).

In 1853 d’Orbigny became professor of paleontology at the Paris Muséum National d’Histoire Naturelle, a new chair created for him. He died at the shockingly young age (for me!) of 54 years.

My friend Paul Taylor at the Natural History Museum in London knows the work of Alcide d’Orbigny very well, and is an expert in his voluminous collections of bryozoans, which you can read about at the link. You will see that the legacy of d’Orbigny is a bit mixed when it comes to his taxonomic contributions, so Paul has his challenges when it comes to sorting out the many names and descriptions this active scientist produced.

References:

Dieni, I. and Middlemiss, F.A. 1981. Pygopid brachiopods from the Venetian Alps. Bollettino della Societá Paleontologica Italiana 20: 19–48.

Kazmer M. 1993. Pygopid brachiopods and Tethyan margins. In: Palfy, J., Voros, A. (eds.), Mesozoic Brachiopods of Alpine Europe. Hungarian Geological Society, Budapest, pp. 59-68.

Michalik, J. 1996. Functional morphology – paleoecology of pygopid brachiopods from the western Carpathian Mesozoic. In: Copper, P. (ed.), Brachiopods: proceedings of the third International Brachiopod Congress, Sudbury, Ontario, Canada, 2-5 September, 1995. CRC Press.

d’Orbigny, A. 1847. Pal. franc., terr. crét., 4, p. 87, pl. 509. Barreme, Lieous, Berrias, Mons, près d’Alais.

Taylor, P.D. 2002. Alcide d’Orbigny (1802-1857). The Linnean 18: 7-12.

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Wooster Geologists Visit the Miller Oil and Gas Museum in Shreve, Ohio

Geology 350 - The Oil and Gas of Geology spending a beautiful day in Shreve.

Drs. Judge and Wiles are teaching a half credit course in The Geology of Oil and Gas. After weeks of well log interpretation, rock core description and interpretive contour mapping exercises the class caught a break and traveled to the Miller Oil and Gas Museum on a beautiful February day in Shreve Ohio. We are grateful to the Raymond’s for showing us around the museum and explaining the use of the some of the equipment.

 

Picking out a plug for an abandoned well.

 

Fishing tools for when there is a problem or a lost drill string downhole.

A proponent of the health benefits of oil.

A class cube - the small class size at Wooster is measured in a cube cell.

One of the old rigs of the oilfields.

A question that commonly comes up is "what would an oilfield geologist do with a cannon?" (see below)

A creative solution to the problem of managing a flaming oil well.

Looking over a field rig.

Destined for law school this geologist models next to a drill string tamper.

 

 

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Wooster’s Fossils of the Week: star sand (Recent of southern Japan)

Yes, that “Recent” in the title was a clue that these are not actually fossils, but the little beauties fit the spirit of our series. This is sand from an unknown island beach in southern Japan. The spotted star-shaped grains are the foraminiferan Baculogypsina sphaerulata (Parker & Jones, 1860). They occur by the billions in tropical and sub-tropical parts of the Pacific Ocean.
Foraminifera are single-celled organisms that often build shells (tests) of calcite and other materials. They have a long fossil record, and we know their evolutionary history in great detail. Foraminifera are thus excellent index fossils for correlating rock units and estimating geological time relationships.
Baculogypsina sphaerulata collected on the famous HMS Challenger expedition of 1873-1876. Image from Brady (1884).

Baculogypsina sphaerulata is an especially interesting foraminiferan. It has a radial canal system that gives it a characteristic star shape. Like many other larger foraminiferans, they have other organisms living inside their tissues called endosymbionts. Here the endosymbionts are pennate (feather-like) diatoms (which was news to me). Diatoms are photosynthetic so they require sunlight to make their carbohydrates. They cluster next to the most transparent parts of the Baculogypsina test interiors, using them like windows to catch some rays. The diatoms release carbohydrate metabolites and oxygen which are used by the host foraminiferan, completing the mutually-beneficial symbiotic relationship.

References:

Brady, H.B. 1884. Report on the Foraminifera dredged by H.M.S. Challenger during the years 1873-1876. Report of the scientific results of the voyage of H.M.S. Challenger, 1873-1876, Zoology 9: 1-814.

Hyams-Kaphzan, O. and Lee, J.J. 2008. Cytological examination and location of symbionts in “living sands” — Baculogypsina. Journal of Foraminiferal Research 38: 298-304.

Lee, J.J., Faber, W.W., Nathanson, B., Roettger, R., Nishihira, M. and Krueger, R. 1993. Endosymbiotic diatoms from larger Foraminifera collected in Pacific habitats. Symbiosis 14: 265-281.

Lee, J.J., Morales, J., Symons, A. and Hallock, P. 1995. Diatom symbionts in larger foraminifera from Caribbean hosts. Marine Micropaleontology 26: 99-105.

Röttger, R. and Krüger, R. 1990. Observations on the biology of Calcarinidae (Foraminiferida). Marine Biology 106: 419-425.

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