This week’s Fossil Friday post showcases a hammerhead (Sphyrna sp.) shark tooth. This particular specimen is from the Milwhite Gunn Farm Mine site in Florida, but fossil hammerhead teeth have been found in the Gatún Formation in Las Lomas and the Chucunaque Formation in Lago Bayano. Hammerhead sharks are found worldwide today but are only found in the Caribbean in the fossil record.
To learn more about fossil hammerhead sharks from Panama, check out the “Fossils of Panama” page on hammerhead shark teeth here.
This week’s Fossil Friday post features the turrid snail Hindsiclava consors (Family Turridae). H. consors would have been found in both on the Caribbean and the Pacific sides of Panama from the early Miocene to the late Pliocene. This specimen was found by Gary Morgan in the Gatún Formation and is late Miocene in age.
This family of predatory snails is known to prey primarily on polychaete worms (Phylum Annelida, Class Polychaeta). One modern-day polychaete worm is the Christmas tree worm, which uses its Christmas tree-shaped appendages for respiration and for filter feeding.
To learn more about this turrid snail, see the “Fossils of Panama” post on it here.
This week’s Fossil Friday is the mandible of the camel Aguascalientia minuta. This specimen was found at the Lirio Norte Graben site in the Las Cascadas Formation and is early Miocene in age. This fossil camel species is the smallest known floridatraguline (Family Floridatragulinae).
To learn more about this specimen, read the publication on it here. Also, be sure to check out another floridatraguline from Panama (Aguascalientia panamaensis) at one of our previous Fossil Friday posts here.
Rincon, A., Bloch, J.I., Suarez, C., MacFadden, B.J., and Jaramillo, C. 2012 New Floridatragulines (Mammalia, Camelidae) From The Early Miocene Las Cascadas Formation, Panama. Journal of Vertebrate Paleontology, 32: 456-475. www.dx.doi.org/10.1080/02724634.2012.635736
This week’s Fossil Friday (the 13th) post features an anthracothere astragalus! This specimen was found in El Lirio Norte of the Las Cascadas Formation and is early Miocene in age. The astragalus is a tarsal, which is a bone found in the ankle. Astragali are very helpful in determining what kind of animal the bone might have belonged to. For example, the “double-pulley” morphology of this anthracothere astragalus is indicative of artiodactyls, so you would also be able to see this kind of morphology in the astragali of camels, deer, and other artiodactyls.
This Fossil Friday I would like to focus on the genus Mellita, a group of flat sand dollars (Class Echinoidea, Order Clypeasteroida). Members of this genus are restricted to the shores of North and South America, however they are found on both the Atlantic and Pacific sides of the continents. Members of Mellita feed by plowing through the surface of sand and collecting food particles. The split that resulted in two extant species of the genus, M. quinquiesperforata and M. notabilis, can be attributed to the closing of the Isthmus of Panama.
To learn more about the current distribution and phylogeography of this genus, read this paper that includes specimens from Panama.
Reference: Coppard, S.E., Zigler, K. S., Lessios, H.A. Phylogeography of the sand dollar genus Mellita: Cryptic speciation along the coasts of the Americas. Molecular Phylogenetics and Evolution. (2013). doi:10.1016/j.ympev.2013.05.028
This Fossil Friday we have a caiman (Family Alligatoridae, Subfamily Caimaninae) named Culebrasuchus mesoamericanus. This specimen was found by PCP PIRE Ph.D. student Aldo Rincon on March 13, 2009 at the El Lirio Norte site of the Culebra Formation, making it early Miocene in age. It is the sister taxon to all other caimans, making it the first documented taxon to have diverged in the caiman evolutionary lineage. Because of this, this specimen can help us learn more about the divergence of alligators and caimans.
To learn more about this specimen, read the publication about it here. You can also read an eNewsletter article on other fossil crocodylians from Panama here.
Hastings, A., Bloch, J., Jaramillo, C., Rincon, A., MacFadden, B. 2013. Systematics and Biogeography of Crocodylians from the Miocene of Panama. Journal of Vertebrate Paleontology 33: 239-263. www.dx.doi.org/10.1080/02724634.2012.713814
For this rendition of Fossil Friday we have the upper tooth of a lemon shark, Negaprion brevirostris. It was collected from the Lirio Este site of the Culebra Formation and is early Miocene in age. Continue reading →
Different views of a cast of UF 280165, a right m1 or m2 of a chalicotheriid. A: Schematic drawing showing morphology of occlusal view; B: Occlusal view; C: Posterior view; D: Buccal view; E: Lingual view. (Figure excerpted from Wood and Ridgwell 2015)
This week’s Fossil Friday is the subject of a paper recently published by former PCP PIRE Post Doc Aaron Wood and Spring 2013 field intern Nicole Ridgwell. The specimen is a right first or second lower molar of a chalicothere (Family Chalicotheriidae), which are an extinct group of clawed perissodactyls. The molar, collected by one of the authors of the paper, Nicole Ridgwell, was found in the Las Cascadas Formation in the Lirio Norte area of the Panama Canal. It is early Miocene in age and is the first record of a chalicothere from Central America.
A mural of a group of chalicotheres called Moropus and other animals they might have shared their environment with. One member of the group is fending off a pair of Daphoenodon. (Mural on display at the Smithsonian, painted by Jay Matternes; photo of mural by FunkMonk)
To access the paper detailing this chalicothere molar, click here.
Reference: Wood, A. R., Ridgwell, N. M. 2015. The first Central American chalicothere (Mammalia, Perissodactyla) and the paleobiogeographic implications for small-bodied schizotheriines, Journal of Vertebrate Paleontology. DOI: 10.1080/02724634.2014.923893
Museum intern Justy Alicea (left) and SMIF technician Jimmy Thostenson set up the CT scanner using a live X-ray image of teeth inside the scanner. (Photo courtesy of Andrea De Renzis)
[This is the unabridged version of museum interns Andrea De Renzis and Justy Alicea’s April 2015 eNewsletter article.]
Traditional specimen-based research in paleontology sometimes requires destructive sampling in order to obtain measurements of features to identify specimens or understand ancient environments. Micro-CT scanning uses x-rays to create high-resolution virtual slices that, when layered together, form a three dimensional model that can be manipulated and measured. These digital models can also be shared with other researchers, educators, and the public, giving more people access to fragile, rare, or scientifically valuable fossils. Continue reading →