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

February 12th, 2016

1 Bolinus brandaris coral reef 585We 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.
2 Bolinus brandaris opened coral reef 585On 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.
3 Gottlieb Pusch on 1944 Nazi stampTo 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.

Wooster’s Fossils of the Week: Gastropod opercula from the Pliocene of Cyprus

January 22nd, 2016

Opercula coral reef Pliocene Cyprus 585This 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.
Astraea_Screen Shot 2013-08-22 at 8.37.54 PM copyAbove 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.

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

January 15th, 2016

Astraea rugosa (Linnaeus, 1767) opened coral reefWe 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.
Astraea rugosa (Linnaeus, 1767) worm coral reefOur 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.

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.

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.

Wooster’s Fossil of the Week: A carnivorous snail from the Pliocene of Cyprus

October 20th, 2013

Euthria Gray 1850 Pliocene Cyprus_585These drab and worn shells from the Pliocene of Cyprus are the remains of deadly little snails still around today. They are from an unknown species of the genus Euthria Gray, 1850. (Sometimes Euthria is considered a subgenus of Buccinulum.) They are fossil whelks (Family Buccinidae) from the Nicosia Formation coral reef community described in earlier posts and in a paper by Dornbos and Wilson (1999).

Whelks are carnivorous snails of a group formerly known as the neogastropods. They have an incredible underwater sense of smell through an organ known as the osphradium, enabling them to track down prey items such as clams, other snails, and carrion. (Yes, “tracking down” mostly sessile critters does seem to lack a bit in drama.) With their radulae (essentially tooth-bearing ribbons) they can drill through thick shells. Some are known to cause extensive damage in oyster farms. Their characteristic boreholes have been found in shells since the Cretaceous.

Euthria is very widespread today, and contains innumerable species poorly separated from each other by shell morphology. No doubt some later genetic study will show that the genus consists of relatively few species with considerable ecophenotypic variability.
John Edward Gray 1851Euthria was described by the English naturalist John Edward Gray (1800-1875) in 1850. Gray, who eventually became a fellow of the Royal Society, started his zoological career in a classic way: he volunteered to collect insects for the British Museum in London when he was just 15 years old. He joined the Museum officially in 1824 and stayed there for 50 years, publishing hundreds of papers on zoological topics, from reptiles and birds to snails and clams. Oddly enough, for all his scientific fame, he is also recognized as the first postage stamp collector. In 1840 he purchased a group of Penny Black stamps in order to save them as curiosities rather than use them for mailing.

References:

Beets, C. 1987. Notes on Buccinulum (Gastropoda, Buccinidae), a reappraisal. Scripta Geologica 82: 83-100.

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.

Fraussen, K. 2002. A new Euthria (Gastropoda: Buccinidae) from New Caledonia. Gloria Maris. Tijdschrift uitgegeven door de Belgische Vereniging voor Conchyliologie 41: 70-74.

Petit, R.E. 2012. John Edward Gray (1800–1875): his malacological publications and molluscan taxa. Zootaxa 3214: 1-125.

Zunino, M. and Pavia, G. 2009. Lower to Middle Miocene Mollusc assemblages from the Torino Hills (NW Italy): Synthesis of new data and chronostratigraphical arrangement. Rivista Italiana di Paleontologia e Stratigrafia 115: 349-370.

Wooster’s Fossil of the Week: A gastropod/coral/hermit crab combination from the Pliocene of Florida

October 6th, 2013

Septastrea marylandica_585These two shells show a lovely symbiosis between shallow marine hermit crabs and encrusting scleractinian corals. I was first introduced to the concept of “pagurized” shells by my friends Paul Taylor and Sally Walker. They showed me the many ways by which shells that were carried around by hermit crabs display particular evidence of this specific use, from characteristic wear patterns to patterns of encrustation and boring. Further, there are some situations, such as that shown above, where encrusters and hermit crabs have developed a mutually beneficial relationship that may have even been depended upon by the crabs.

What we have here are gastropod (snail) shells that have been completely encrusted by the scleractinian coral Septastrea marylandica (Conrad, 1841). These are found in great abundance in the Pliocene Pinecrest Sand (foraminiferal zone N20) near Fruitville, Sarasota County, Florida. What is most cool is that the corals have completely encrusted these spiraling snail shells and more. If you look carefully at the aperture of the specimen on the left you see the lower surface of the coral with no snail shell. The coral had encrusted the whole shell and continued to grow from the original aperture outward, elongating the twisting tube farther than the snail ever grew. Why (and how) did it do this?

The answer is that the shells were occupied by hermit crabs. The corals extended the aperture of the shell with the crab shuffling about in the opening. The crabs gained the advantage of a shell that essentially grew along with them, meaning they did not have to make the dangerous switch to a larger shell as often. The corals gained by being carried about into diverse microenvironments, extending their feeding possibilities. Nice arrangement, and elegant fossils to show it.
Septastrea closeSeptastrea marylandica (Conrad, 1841) is a scleractinian coral. We’ve seen this order before on this blog, but usually as a recrystallized version of the original aragonitic shell. In these specimens the aragonite is still preserved in excellent detail. Each of the individual “cups” (corallites) above contained a single coral polyp in life. The radiating vertical walls are called septa and are related to the original soft parts of the polyps. The polyps extended tentacles from these corallites into the surrounding seawater. The tentacles were lined (as they are today) with stinging cells called nematocysts for subduing very small items of prey, such as larvae or tiny arthropods. Corals thus represent an ecological group of sessile benthic epifaunal predators. Sessile means stationary, benthic means on the seafloor, and epifaunal means on the surface of the seafloor (that is, not in the substrate itself). Curiously, then, these corals that encrusted shells with hermit crabs in them became in a sense vagrant rather than benthic because they were moved about on the seafloor. You don’t hear about vagrant benthic corals very often!

References:

Allmon, W.D. 1993. Age, environment and mode of deposition of the densely fossiliferous Pinecrest Sand (Pliocene of Florida): Implications for the role of biological productivity in shell bed formation. Palaios 8: 183-201.

Darrell, J.G. and Taylor, P.D. 1989. Scleractinian symbionts of hermit crabs in the Pliocene of Florida. Memoir of the Association of Australasian Palaeontologists 8:115–123.

Laidre, M.E. 2012. Niche construction drives social dependence in hermit crabs. Current Biology 22: R861–R862.

Petuch, E J. 1986. The Pliocene reefs of Miami: Their geomorphological significance in the evolution of the Atlantic coastal ridge, southeastern Florida, USA. Journal of Coastal Research 2: 391-408.

Taylor, P.D. and Schindler, K.S. 2004. A new Eocene species of the hermit-crab symbiont Hippoporidra (Bryozoa) from the Ocala Limestone of Florida. Journal of Paleontology 78: 790-794.

Vermeij , G.J. 2012. Evolution: Remodelling hermit shellters. Current Biology 22: R882-R884. [Really. The title is spelled exactly this way.]

Walker, S.E. 1992. Criteria for recognizing marine hermit crabs in the fossil record using gastropod shells. Journal of Paleontology 66: 535-558.

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