Wooster Geologists

This shell looks like a cinnamon roll. It is another product of the 1996 Wooster-Keck expedition to Cyprus with Steve Dornbos (’97) and me. Like the rest of the Cypriot specimens on this blog, it is from the Nicosia Formation (Pliocene) exposed on the Mesaoria Plain in the center of the island. This specimen comes from the Coral Reef locality described in Dornbos and Wilson (1999). We are looking at a well-preserved specimen of the herbivorous gastropod Gibbula Risso, 1826. (I can’t fit it into any known species within the genus.)
In this side view the growth lines are evident (they are parallel to the aperture; the thin ribs following the whorls are ornamentation), as are a couple of shallow, circular pits drilled by some unsuccessful predator. That predator could have been another gastropod or even an octopus. The pits are known by the trace fossil name Oichnus.

Those growth lines are interesting in  this genus. Schöne et al. (2007) studied a species of modern Gibbula and determined that they formed “microgrowth lines” in association with tidal cycles, forming “distinct fortnight bundles of microgrowth increments and lines”. We would need to section this shell and examine it microscopically to see such patterns.

Here is the basal view of our Gibbula specimen.

The genus Gibbula was named and described by Giuseppe Antonio Risso (1777-1845), called Antoine Risso, was a productive Italian (more or less; he later can be considered French) naturalist. He was born in the city of Nice, then in the Duchy of Savoy. In 1792, soon after the French Army occupied Nice, Risso became a pharmacist’s apprentice, which encouraged his interest in medicinal botany. Risso was also a pioneering mountaineer in the Alps and other European ranges. He published several books on invertebrates, fish and plants. The work most relevant to us is his 1826 tome entitled: Histoire naturelle des principales productions de l’Europe Méridionale et particulièrement de celles des environs de Nice et des Alpes Maritimes. Risso’s Dolphin is named after him.

References:

Donnarumma, L., Bruno, R., Terlizzi, A. and Russo, G.F. 2015. Population ecology of Gibbula umbilicaris and Gibbula ardens (Gastropoda: Trochidae) in a Posidonia oceanica seagrass bed. Italian Journal of Zoology, DOI: 10.1080/11250003.2015.1073377

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.

Risso, A. 1826. Histoire naturelle des principales productions de l’Europe Méridionale et particulièrement de celles des environs de Nice et des Alpes Maritimes. Paris: F.G. Levrault. Vol. 4: IV, 1-439, 12 pls.

Schöne, B.R., Rodland, D.L., Wehrmann, A., Heidel, B., Oschmann, W., Zhang, Z., Fiebig, J. and Beck, L. 2007. Combined sclerochronologic and oxygen isotope analysis of gastropod shells (Gibbula cineraria, North Sea): life-history traits and utility as a high-resolution environmental archive for kelp forests. Marine Biology 150: 1237-1252.

Williams, E.E. 1964. The growth and distribution of Gibbula umbilicalis (da Costa) on a rocky shore in Wales. The Journal of Animal Ecology 33: 433-442.

Cyprus again for this week’s fossil. This is a nearly complete shell of the predatory snail Conus pelagicus Brocchi 1814 found at the Epsilos exposure of the Nicosia Formation (Pliocene) on the Mesaoria Plain of central Cyprus by Steve Dornbos (’97) and me in 1996. In life this species no doubt had an intricate shell color pattern, as their cousins do today.

The taxonomic intricacies of the genus Conus are far beyond the scope of a mere blog entry, so I’ll simply link to a list of associated genera, subgenera and synonymies. Conus as an organism is fantastic. These are venomous predators famous for shooting radular teeth loaded with very effective toxins. Some species can kill a human in less than five minutes. No worries, though — the venom contains analgesic compounds so there is little pain. The best way to demonstrate the extraordinary killing process used by Conus is to look at a video. You’ll never look at snails the same way again.
Conus pelagicus was originally described by Giovanni Battista Brocchi in 1814. We met him in a previous blog entry, so much of this information is repeated. Brocchi (1772-1826) was an Italian natural historian who made significant contributions to botany, paleontology, mineralogy and general geology. He was born in Bassano del Grappa, Italy, and studied law at the University of Padova. He liked mineralogy and plants much better than lawyering, though, and became a professor in Brescia. His work resulted in an appointment as Inspector of Mines in the new kingdom of Italy. He famously said, “The science of fossil shells is the first step towards the study of the earth.”

Brocchi wrote the first thorough geological assessment of the Apennine Mountains, and he included in it a remarkable systematic study of Neogene fossils. He compared these fossils to modern animals in the Mediterranean — a very progressive thing to do at the time.
Above are drawings made by Brocchi of the conid (and a couple cypraeid) fossils he found in the Apennines during his extensive study published in 1814. Note that in the Continental fashion still followed today, the shells are figured aperture-up. Americans and the rest of the English-speaking world orient them in the proper way. Figures 11a, b and c, though, are oriented in the opposite direction, maybe to fill the space efficiently.

Brocchi was an adventurous traveler, but it eventually did him in. He died in Khartoum in 1826, a “victim of the climate” and a martyr for field science.

References:

Brocchi, G.B. 1814. Conchiologia fossile subapennina con osservazioni geologiche sugli Apennini e sul suolo adiacente. Milano Vol. I: pp. LXXX + 56 + 240; Vol. II, p. 241-712, pl. 1-16.

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.

We return to Cyprus for this week’s fossil. This is a broken shell of the predatory muricid Bolinus brandaris (Linnaeus, 1758) found at the Coral Reef exposure of the Nicosia Formation (Pliocene) on the Mesaoria Plain of central Cyprus by Steve Dornbos (’97) and myself in 1996. It has had some significant battering, probably by a crab peeling away the shell to get to the goodies. The ribs are prominent on the whorls, representing previous strengthened apertures. The base was a long, narrow siphonal canal now broken off. You can see the complete shell shape in modern examples.
On the other side of the same specimen we see that the last whorl has been opened, showing the spiral columella at the axis of coiling. The arrow points to a puncture hole in an upper whorl. This appears to be the result of a “ballistic” impact on the shell by some predatory organism. Pether (1995) gave the name Belichnus to this trace fossil, attributing it to stomatopod crustaceans and their wicked-fast and powerful claws. Cadée and de Wolf (2013) expanded the possible tracemakers of Belichnus to seagulls.

Bolinus brandaris is well known today throughout the Mediterranean as the Purple Dye Murex. It has been used since ancient times as the source of a deep, permanent fabric dye called Tyrian Purple. It was highly prized by royalty and the wealthy elite for millennia.

Linnaeus originally placed this species in the genus Murex, but in 1837 Georg Gottlieb Pusch described a new but similar genus Bolinus, to which the species now belongs. Pusch, who also had the Polish name Jerzy Bogumił Koreński, was a very interesting fellow in the early days of paleontology and geology. He was born in Kohren, Saxony, in 1790 (or 1791, depending on which calendar you use). He was very early interested in what would become geology, so in 1806 he enrolled in the Mining Academy in Freiberg. In his first year he was recognized as an outstanding student by the famous Abraham Gottlob Werner. In 1811 he also studied law in Leipzig. After graduating he explored the geology of Saxony, and in 1813 participated in battles against Napoleon. Then in 1816, Pusch moved to Poland, which at that time was partitioned by foreign powers. He became professor of Chemistry and Metallurgy at the Kielce Academy and later head of the Mining and Mineralogy Department in Warsaw. His most important geological work was to explore and describe the geology of the Carpathians. He died in 1846.
To his misfortune, a portrait of Georg Gottlieb Pusch was used on the above 1944 German Occupation of Poland postage stamp, probably for the simple reason that he was a German who had done well in the Polish territories. I like to think Pusch would have been appalled to have been used in this way. He was a hero of geology.

References:

Cadée, G. C. and de Wolf, P. 2013. Belichnus traces produced on shells of the bivalve Lutraria lutraria by gulls. Ichnos 20: 15-18.

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.

Pether, J. 1995. Belichnus new ichnogenus, a ballistic trace on mollusc shells from the Holocene of the Benguela region, South Africa. Journal of Paleontology 69: 171-181.

Radwin, G.E. and D’Attilio, A. 1986. Murex shells of the world. An illustrated guide to the Muricidae. Stanford University Press, Stanford, 284 pages.

This week’s brief entry (it is short because we’re in the first few days of a new semester at Wooster) is related to last week’s post. Above are two gastropod opercula from the Nicosia Formation (Pliocene) of Cyprus. They were collected on a Keck Geology Consortium expedition to Cyprus in the summer of 1996 with Steve Dornbos (’97). An operculum for a gastropod is a kind of hard door attached to the muscular foot that closes off the aperture when the snail is fully retracted into its shell. On the left is the inside of an operculum, and on the right is the elegantly spiraled outside. The operculum provides protection for the snail from both drying out during a low tide and from prying (literally!) predators.

We can’t tell for certain, but we think these opercula are from the herbivorous gastropod Astraea rugosa featured in last week’s entry. We found them at our fossil coral reef site in the same deposit as the A. rugosa shells. They also look very much like these modern A. rugosa opercula.
Above is a diagram of Astraea rugosa with the operculum (“opérculo calcificado”) in place. (The drawing comes from a Spanish webpage no longer in existence.)

References:

Checa, A.G. and Jiménez-Jiménez, A.P. 1998. Constructional morphology, origin, and evolution of the gastropod operculum. Paleobiology 24: 109-132.

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.

We saw this broken gastropod from the Pliocene of Cyprus in this blog post about two and a half years ago. I recently rediscovered it while sorting specimens and decided to show this intriguing perspective through the broken part of the shell. It was collected on a Keck Geology Consortium expedition to Cyprus in the summer of 1996. My Independent Study student on that expedition was Steve Dornbos (’97), now a professor of geology at the University of Wisconsin, Milwaukee. One sunny day Steve and I came across a beautiful coral reef weathering out of the silty Nicosia Formation (Pliocene) on the hot and dry Mesaoria Plain in the center of the island near the village of Meniko (N 35° 5.767′, E 33° 8.925′ — go ahead, search these coordinates for a great satellite view). The reef records the early recovery of marine faunas following the Messinian Salinity Crisis and the subsequent refilling of the basin (the dramatic Zanclean Flood). Steve and I published our observations and analyses of this reef community in 1999.
Our featured fossil is the herbivorous turbinid gastropod Astraea rugosa (Linnaeus, 1767). That beautiful generic name means “star-maiden” in Greek and was originally used by Linnaeus in homage to the mythological Astraea, daughter of Zeus (maybe) and a “celestial virgin”. The species name rugosa means “rough” or “wrinkled”, in reference to the many ridges on the shell. The common name for this species, which is still alive today (as you can see in this video) is “rough star”. In the top image you can see the internal shell twist at the axis of coiling called the columella. In the image above is a delicate little coiled tube of the vermetid gastropod Petaloconchus preserved where it attached to the shell about five million years ago.

Stay tuned here for additional fossils from the Pliocene of Cyprus. They are too good not to share!

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.