A river runs through an Oligocene sea

The subject of this post is about my second and final day of fieldwork in Puerto Rico. Yes, I only managed to get two days of fieldwork because these were actually some very short vacations and on top of that it was very rainy. Anyways, I already wrote about my first day of fieldwork during which I searched for tetrapods in the Late Oligocene Lares Limestone. Now on my second day I went out to one of my favorite localities, herein referred to as Río G. This locality consists of exposures of the Early Oligocene age San Sebastián Formation along the banks of a river (See the picture below with me as scale and outcrops on each side of the river). The exposures along this river are considered as typical of the basal part of this formation (Monroe, 1980). The lithology of this formation is varied, with some layers representing ancient soils, river channels, deltaic deposits as well as marine units. Of course this is all in a sequence that makes sense with the tectonic history and paleogeography of the region, an interesting subject, which I will not touch at this moment, but might be discussed sometime in the future.

Now, some interesting tetrapods have been recovered from this formation, such as the sirenian Caribosiren turneri, described by Reinhart in 1959. Also from this formation are known pelomedusid turtles, which were previously discussed here. From the Río G locality, one of the more recent discoveries is the skull of the gryposuchine gavialid Aktiogavialis puertoricensis (Velez-Juarbe, et al. 2007). Other tetrapods found here, include sirenians, part of a croc axial skeleton and the oldest-but-crappiest rodent fossil from the Caribbean region. Some of these, like the sirenians are part of my thesis project, whereas the others are still awaiting description or for better material to turn up.

Unfortunately, same as with the prospecting in the Lares Limestone, no new or even useful vertebrate fossils were found in Río G. The most interesting fossil I found was a plant fossil that might be a seed or some sort of fruit (see picture below of the seed/fruit together with a schematic drawing – the fossil measures about 27 mm across). If it actually turns out to be a seed/fruit it would not be the first time that plant “megafossils” are found in the San Sebastián Formation; about 88 taxa of plant macrofossils from this formation were described by Sir Arthur Hollick in the 1920’s (Graham, 1996). I have yet to see Hollick’s (1926, 1928) papers; therefore I still don’t know if my fossil is similar to any of the material he described.

Well, at least since Río G is along a body of water, it turned out a nice place to do some bird watching. I have on previous occasions observed some of the birds along this river, with the difference that now I had a camera with a good zoom allowing me to take some nice pictures. The composite picture below include, clockwise beginning with the upper left: male Molothrus bonariensis (shiny cowbird); Butorides striatus (green-backed heron); Egretta caerulea (little blue heron); Actitis macularia (spotted sandpiper, this one has the winter plumage hence the lack of spots).

An interesting fact about the shiny cowbird is that it is an invasive species from South America, first reported from the Caribbean region during the latter half of the 1800’s (Post & Wiley, 1977a). It is also a brood parasite; in Puerto Rico it parasitizes about 16 different species of birds with a preference for the yellow-shouldered blackbird (Agelaius xanthomus) (Post & Wiley, 1977b; Pérez-Rivera, 1986). These are actually bad news as the yellow-shouldered blackbird is an endemic to the Puerto Rico bank.

On the earlier half of the day, while stalking a green-backed heron (Butorides striatus), I was unwillingly reminded to always keep an eye of where I put my feet. The reason was that while trying to stealthily sneak up to see where the bird was standing, I almost ended up stepping on a couple of fairly large green iguanas (Iguana iguana) (see composite picture below)!

This was actually the first time I have seen green iguanas in the wild in this part of the island. Iguanas are an introduced pest in Puerto Rico therefore their occurrence in this locality took me totally by surprise, although I am aware that they are getting more common around the island, specially in the east and north where it is more humid (I believe they are still not present in the drier southern coast or that they are much less common there). Green iguanas are doing really well in Puerto Rico; the reason might be that once they reach an adult size, nothing, except maybe humans, will eat them. Perhaps another reason for their success is that until several thousand years ago there were Anegada rock iguanas (Cyclura pinguis) in Puerto Rico (Pregill, 1981); are then green iguanas just filling in an empty niche left over by the extinction of the Anegada rock iguana from Puerto Rico? This is unlikely; rock iguanas (Cyclura spp.) are adapted to xeric environments, which, unlike today, were present in northern PR during the Pleistocene (Pregill & Olson 1981). This means that the habitat that was occupied by C. pinguis in northern Puerto Rico, no longer exist there (rock iguanas are not the only xeric-adapted tetrapod to go extinct in northern PR [op. cit.]). All I know is that from now on I will have to keep an eye out for green iguanas while doing fieldwork, at least in northern Puerto Rico.

References

Graham, A. 1996. Paleobotany of Puerto Rico-from Arthur Hollick’s (1928) scientific survey paper to the present. Annals of the New York Academy of Sciences 776: 103-114.

Hollick, A. 1926. Fossil walnuts and lignite from Porto Rico. Journal of the New York Botanical Garden 27:223-227.

Hollick, A. 1928. Paleobotany of Porto Rico. Scientific Survey of Porto Rico and the Virgin Islands 7(3):177-393.

Monroe, W. H. 1980. Geology of the middle Tertiary formations of Puerto Rico. US Geological Survey Professional Paper 953:1-93.

Pérez-Rivera, R. A. 1986. Parasitism by the shiny cowbird in the interior parts of Puerto Rico. Journal of Field Ornithology 57(2):99-104.

Post, W. & J. Wiley. 1977a. The shiny cowbird in the West Indies. Condor 79:119-121.

Post, W. & J. Wiley. 1977b. Reproductive interactions of the shiny cowbird and the yellow-shouldered blackbird. Condor 79:176-184.

Pregill, G. K. 1981. Late Pleistocene herpetofaunas from Puerto Rico. University of Kansas Museum of Natural History, Miscellaneous Publications 71:1-72.

Pregill, G. K. & S. L. Olson. 1981. Zoogeography of the West Indian vertebrates in relation to Pleistocene climatic cycles. Annual Review of Ecology and Systematics 12:75-98.

Reinhart, R. H. 1959. A review of the Sirenia and Desmostylia. University of California Publications in Geological Sciences 36(1):1-146.

Velez-Juarbe, J., C. A. Brochu & H. Santos. 2007. A gharial from the Oligocene of Puerto Rico: transoceanic dispersal in the history of a nonmarine reptile. Proceedings of the Royal Society B 274:1245-1254.

Publicaciones de fósiles de Puerto Rico / Publications on fossils from Puerto Rico

Para esta nota he recopilado un listado de publicaciones que tratan sobre fósiles de Puerto Rico. Por supuesto que el listado está viciado a favor de publicaciones sobre vertebrados fósiles los cuales son mis favoritos o invertebrados con los cuales he trabajado en el pasado. Si conoces referencias adicionales me puedes avisar (a través de correo electrónico o comentarios abajo) para asi añadirlos a la lista. Algunas de las referencias incluso están enlazados su pdf gratis.

For this post I have compiled a list of publications that deals with fossils from Puerto Rico. Of course it is somewhat biased toward vertebrates, which are my favorites or invertebrates on which I have worked on previous occasions. If you know additional references that are not here just let me know (either through emails or comments below) and they will be added. Some of these are linked to their free pdf.

Updated: 29/January/2024

Allen, J. A. 1916. An extinct octodont from the island of Porto Rico, West Indies. Annals of the New York Academy of Sciences 27:17-22.

Anthony, H. E. 1916a. Preliminary diagnosis of an apparently new family of insectivores. Bulletin of the American Museum of Natural History 35(41):725-728.

Anthony, H. E. 1916b. Preliminary report of fossil mammals from Porto Rico, with descriptions of a new genus of ground sloth and two new genera of hystricomorph rodents. Annals of the New York Academy of Sciences 27:193-203.

Anthony, H. E. 1917a. New fossil rodents from Porto Rico, with additional notes on Elasmodontomys obliquus Anthony and Heteropsomys insulans Anthony. Bulletin of the American Museum of Natural History 37(4):183-190.

Anthony, H. E. 1917b. Two new fossil bats from Porto Rico. Bulletin of the American Museum of Natural History 37(19):565-568.

Anthony, H. E. 1918. The indigenous land mammals of Porto Rico, living and extinct. American Museum of Natural History, Memoirs 1(2):329-435.

Anthony, H. E. 1925. Mammals of Porto Rico, living and extinct—Chiroptera and Insectivora. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands IX:1–96.

Anthony, H. E. 1926. Mammals of Porto Rico, living and extinct—Rodentia and Edentata. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands IX:97–241.

Auffenberg, W. 1967. Notes on West Indian tortoises. Herpetologica 23(1):34-44.

Bandini, A. N., P. O. Baumgartner, K. Flores, P. Dumitrica, C. Hochard, G. M. Stampfli, and S.-J. Jackett. 2011. Aalenian to Cenomanian Radiolaria of the Bermeja Complex (Puerto Rico) and Pacific origin of radiolarites on the Caribbean Plate. Swiss Journal of Geociences 104:367-408.

Banerjee, A., K. Yemane, and A. Johnson. 2000. Foraminiferal biostratigraphy of late Oligocene-Miocene reefal carbonates in southwestern Puerto Rico. Micropaleontology 46(4):327-342.

Barbour, T. 1919. A new rock iguana from Puerto Rico. Proceedings of the Biological Society of Washington 32:145-148.

Bermúdez, P. J., and G. A. Seiglie. 1967. A new genus and species of foraminifer from the early Miocene of Puerto Rico. Tulane Studies in Geology 5:177–179.

Bermúdez, P. J., and G. A. Seiglie. 1970. Age, paleoecology, correlation and foraminifers of the uppermost Tertiary formation of northern Puerto Rico. Caribbean Journal of Science 10:17-33.

Blackburn, D. C., R. M. Keeffe, M. C. Vallejo-Pareja, and J. Velez-Juarbe. 2020. The earliest record of Caribbean frogs: a fossil coquí from Puerto Rico. Biology Letters 16:20190947.

Bonilla-Rodríguez, A. J., L. A. González, J. D. Walker, and H. Santos. 2014. Strontium isotope (87Sr/86Sr) stratigraphy from the Coalcomana-Caprinuloidea rudist assemblage in the Greater Antilles (Puerto Rico, Dominican Republic and Jamaica). Cretaceous Research 50:97-109.

Brochu, C. A., A. M. Nieves-Rivera, J. Velez-Juarbe, J. D. Daza-Vaca and H. Santos. 2007. Tertiary crocodylians from Puerto Rico: evidence for late Tertiary endemic crocodylians in the West Indies? Geobios 40:51-59.

Choate, J. R. and E. C. Birney. 1968. Sub-recent Insectivora and Chiroptera from Puerto Rico, with the description of a new bat of the genus Stenoderma. Journal of Mammalogy 49(3):400-412.

Cobban, W. A., and G. R. Scott. 1988. Occurrence of the early Cretaceous Ammonite Venezoliceras in Puerto Rico. U.S. Geological Survey Bulletin 1837:D1–D2.

Coryell, H. N., and V. Ohlsen. 1929. Fossil corals of Porto Rico, with descriptions also of a few recent species. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands 3(3):169-236.

Cutress, B. M. 1980. Cretaceous and Tertiary Cidaroida (Echinodermata, Echinoidea) of the Caribbean area. Bulletin of American Paleontology 77:1-221.

Da Cunha, L., L. W. Viñola-López, R. D. E. MacPhee, L. Kerber, J. Vélez-Juarbe, P.-O. Antoine, M. Boivin, L. Hautier, R. Lebrun, L. Marivaux, and P.-H. Fabre. 2023. The inner ear of caviomorph rodents: phylogenetic implications and application to extinct West Indian taxa. Journal of Mammalian Evolution 30:1155–1176.

Domning, D. P. and O. A. Aguilera. 2008. Fossil Sirenia of the West Atlantic and Caribbean region. VIII. Nanosiren garciae, gen. et sp. nov. and Nanosiren sanchezi, sp. nov. Journal of Vertebrate Paleontology 28(2):479-500.

Donovan, S. K., S. N. Nielsen, J. Velez-Juarbe, R. W. Portell. 2019. The isocrinine crinoid Isselicrinus Rovereto from the Paleogene of the Americas. Swiss Journal of Palaeontology 138:317-324.

Edinger, E. N., and M. J. Risk. 1994. Oligocene-Miocene extinction and geographic restriction of Caribbean corals: roles of turbidity, temperature, and nutrients. PALAIOS 9(6):576-598.

Flemming, C. and R. D. E. MacPhee. 1999. Redetermination of holotype of Isolobodon portoricensis (Rodentia, Capromyidae), with notes on recent mammalian extinctions in Puerto Rico. American Museum Novitates 3278:1-11.

Frank, E. F. and R. Benson. 1998. Vertebrate paleontology of Mona Island, Puerto Rico. Journal of Cave and Karst Studies 60:103-106.

Frost, S. H., J. L. Harbour, D. K. Beach, M. J. Realini, and P. M. Harris. 1983. Oligocene reef track development, southwestern Puerto Rico. Sedimenta 9:1-144.

Gaffney, E. S., and R. C. Wood. 2002. Bairdemys, a new side-necked turtle (Pelomedusoides: Podocnemididae) from the Miocene of the Caribbean. American Museum Novitates 3359:1-28.

Galloway, J. J., and C. E. Hemingway. 1941. The Tertiary Foraminifera of Porto Rico. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands 3(4):275-491.

Gordon, W. A. 1960. The age of the middle Tertiary rocks of northwestern Puerto Rico. Second Caribbean Geological Conference, Transactions. 87–90.

Gordon, W. A. 1961. Distribution of Foraminifera in the middle Tertiary San Sebastián-Isabela section, Puerto Rico. Caribbean Journal of Sciences 1(2):48–58.

Gordon, W. A. 1961. Miocene Foraminifera from the Lajas Valley, Southwest Puerto Rico. Journal of Paleontology 35(3):610-619.

Gordon, W. A. 1961. Planktonic foraminifera and the correlation of the middle Tertiary rocks of Puerto Rico. Micropaleontology 7(4):451-460.

Gordon, W. A. 1963. Middle Tertiary echinoids of Puerto Rico. Journal of Paleontology 37(3):628-642.

Gordon, W. A. 1966. Two crab species from the middle Tertiary of Puerto Rico. Transactions of the Third Caribbean Geological Conference, Kingston, Jamaica, 2nd-11th April, 1962:184-186.

Graham, A. 1996. Paleobotany of Puerto Rico-from Arthur Hollick’s (1928) scientific survey paper to the present. Annals of the New York Academy of Sciences 776: 103-114.

Graham, A. and D. M. Jarzen. 1969. Studies in neotropical botany. I. The Oligocene communities of Puerto Rico. Annals of the Missouri Botanical Garden 56:308-357.

Herrera, F., S. R. Manchester, J. Velez-Juarbe, and C. Jaramillo. 2014. Phytogeographic history of the Humiriaceae (Part 2). International Journal of Plant Sciences 175:828-840.

Hollick, A. 1924. A review of the fossil flora of the West Indies, with description of new species. Bulletin of the New York Botanical Garden 12:259–323.

Hollick, A. 1926. Fossil walnuts and lignite from Porto Rico. Journal of the New York Botanical Garden 27:223-227.

Hollick, A. 1928. Paleobotany of Porto Rico. Scientific Survey of Porto Rico and the Virgin Islands 7(3):177-393.

Howell, B. F. 1966. New Upper Cretaceous sponge from Puerto Rico. Journal of Paleontology 40(1):207-209.

Hubbard, B. 1920. Tertiary Mollusca from the Lares district, Porto Rico. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands 3(2):79-164.

Hubbard, B. 1923. The geology of the Lares District, Porto Rico. New York Academy of Science Survey of Porto Rico and the Virgin Islands, 2, 115 p.

Iturralde-Vinent, M. A. 2001. Geology of the amber-bearing deposits of the Greater Antilles. Caribbean Journal of Science 37(3-4):141-167.

Iturralde-Vinent, M. A. and E. Harstein. 1998. Miocene amber and lignitic deposits in Puerto Rico. Caribbean Journal of Science 34:308-312.

Jackson, R. T. 1922. Fossil echini of the West Indies. Carnegie Institution of Washington Publication 306:1-103.

Kauffman, E., and N. F. Sohl. 1974. Structure and evolution of Antillean Cretaceous rudist frameworks. Verhandlungen der naturforschenden Gessellchaft in Basel 84:399–467.

Krijnen, J. P. 1978. Pseudorbitoids from the Parguera Limestone, Puerto Rico, and from the Back Rio Grande Limestone, Jamaica, with remarks on the pseudorbitoidal evolutionary pattern. Geologie en Mijnbouw 57:233–242.

Luque, J., C. E. Schweitzer, W. Santana, R. W. Portell, F. J. Vega, A. A. Klompmaker. 2017. Checklist of fossil decapod crustaceans from Tropical America. Part I: Anomura and Brachyura. Nauplius 25:e2017025.

MacPhee, R.D.E. 2011. Basicranial morphology and relationships of Antillean Heptaxodontidae (Rodentia, Ctenohystrica, Caviomorpha). Bulletin of the American Museum of Natural History 363:1-70.

MacPhee, R.D.E. and M.A. Iturralde-Vinent. 1995. Origin of the Greater Antillean land mammal fauna, 1: new Tertiary fossils from Cuba and Puerto Rico. American Museum Novitates 3141:1-31.

MacPhee, R. D. E. and A. R. Wyss. 1990. Oligo-Miocene vertebrates from Puerto Rico, with a catalog of localities. American Museum Novitates 2965:1-12.

Marivaux, L., J. Velez-Juarbe, and P.-O. Antoine. 2020. 3D models related to the publication: Early Oligocene chinchilloid caviomorphs from Puerto Rico and the initial rodent colonization of the West Indies: 3D models of Oligocene Puerto Rican chinchilloids. MorphoMuseum, Association Palaeovertebrata 6(4):e127. DOI: 10.18563/journal.m3.127

Marivaux, L., J. Velez-Juarbe, and P.O. Antoine. 2021. 3D models related to the publication: An unpredicted ancient colonization of the West Indies by North American rodents: dental evidence of a geomorph from the early Oligocene of Puerto Rico. MorphoMuseum, Association Palaeovertebrata 7:e128. DOI: 10.18563/journal.m3.128

Marivaux, L., L. W. Viñola-López, M. Boivin, L. Da Cunha, P.-H. Fabre, R. Joannes-Boyau, G. Maincent, P. Münch, N. S. Stutz, J. Vélez-Juarbe, and P.-O. Antoine. 2022. Incisor enamel microstructure of West Indian caviomorph hystricognathous rodents (Octodontoidea and Chinchilloidea). Journal of Mammalian Evolution. DOI: 10.1007/s10914-022-09631-7

Marivaux, L., J. Velez-Juarbe, G. Merzeraud, F. Pujos, L. W. Viñola López, M. Boivin, H. Santos-Mercado, E. J. Cruz, A. Grajales, J. Padilla, K. I. Vélez-Rosado, M. Philippon, J.-L. Léticée, P. Münch, and P.-O. Antoine. 2020. Early Oligocene chinchilloid caviomorphs from Puerto Rico and the initial colonization of the West Indies. Proceedings of the Royal Society B 287:20192806.

Marivaux, L., J. Velez-Juarbe, L. W. Viñola López, P.-H. Fabre, F. Pujos, H. Santos-Mercado, E. J. Cruz, A. Grajales Pérez, J. Padilla, K. I. Vélez-Rosado, J.-J. Cornée, M. Philippon, P. Münch, and P.-O. Antoine. 2021. An unpredicted ancient colonization of the West Indies by North American rodents: dental evidence of a geomorph from the early Oligocene of Puerto Rico. Papers in Palaeontology 1–19. DOI: 10.1002/spp2.1388

Matthew, W. D. 1916. New sirenian from the Tertiary of Porto Rico. Annals of the New York Academy of Sciences 27:23-29.

Matthew, W. D. 1918. Affinities and origin of the Antillean mammals. Bulletin of the Geological Society of America 29:657-666.

Matthew, W. D. 1919. Recent discoveries of fossil vertebrates in the West Indies and their bearing on the origin of the Antillean Fauna. Proceedings of the American Philosophical Society 58:161-181.

Mattson, P. H., and E. A. Pessagno, Jr. 1979. Jurassic and Early Cretaceous radiolarians in Puerto Rican ophiolite—Tectonic implications. Geology 7:440–444.

Maury, C. J. 1920. Tertiary Mollusca from Porto Rico and their zonal relations. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands 3(1):1-77.

McDowell, S. B. 1958. The Greater Antillean insectivores. Bulletin of the American Museum of Natural History 115:113-214.

McFarlane, D. A. 1999. A note on dimorphism in Nesophontes edithae (Mammalia: Insectivora), an extinct island-shrew from Puerto Rico. Caribbean Journal of Science 35:142-143.

McFarlane, D. A. 1999. Late Quaternary fossil mammals and last occurrence dates from caves at Barahona, Puerto Rico. Caribbean Journal of Science 35(3-4):238-248.

Mitchell, S. F. 2013. Revision of the Antillocaprinidae Mac Gillavry (Hippuritida, Bivalvia) and their position within the Caprinoidea d'Orbigny. Geobios 46:423–446.

Mitchell, S. F. 2020. Exceptionally well-preserved silicified hippuritid rudist bivalves from the lower Maastrichtian of Puerto Rico. Carnets de Géologie 20:333–366.

Mitchell, S. F. 2022. Revision of the hippuritid rudists from the Pozas Formation (upper Santonian/lower to middle Campanian), Puerto Rico, and their evolutionary and stratigraphical significance. Cretaceous Research 138:105289.

Mitchell, S. F., M. Martínez-Colón, R. Ramsook and H. Santos. 2012. A primitive tube-bearing antillocaprinid rudist bivalve, Parasarcolites sohli, sp. nov., from Jamaica and Puerto Rico, West Indies. Cretaceous Research 34:149-153.

Montgomery, H., E. Robinson, J. Saunders, W. Van den Bold. 1991. Paleontology of the Toa Baja #1 well, Puerto Rico. Geophysical Research Letters 18:509-512.

Morgan, G. S. 2001. Patterns of Extinction in West Indian Bats; pp. 369-407 in C. A. Woods and F. E. Sergile (eds.), Biogeography of the West Indies: Patterns and Perspectives, Second Edition. CRC Press, Boca Raton, Florida.

Moussa, M. T. 1974. Tertiary brachiopods from Puerto Rico and their paleontologic and paleoecologic significance. Journal of Paleontology 48(6):1202-1206.

Moussa, M. T., and G. A. Seiglie. 1970. Revision of Mid-Tertiary stratigraphy of Southwestern Puerto Rico. American Association of Petroleum Geologists Bulletin 54:1887–1898.

Nieves-Rivera, A. M. 2007. Paleobotanical notes on mangrove-like plants of Puerto Rico. Interciencia 32:175-179.

Nieves-Rivera, A. M., J. E. Mylroie, and D. A. McFarlane. 1995. Bones of Puffinus lherminieri Lesson (Ages: Procellaridae) and two other vertebrates from Cueva del Agua, Mona Island, Puerto Rico (West Indies). National Speleological Society Bulletin 57:99-102.

Nieves-Rivera, A. M., M. Ruiz-Yantín and M.D Gottfried. 2003. New record of the Lamnid shark Carcharodon megalodon from the Middle Miocene of Puerto Rico. Caribbean Journal of Science 39:223-227.

Nieves-Rivera, Á. M., J. P. Zegarra Vila, C. E. Figuerola Hernández, J. E. García-Hernández, and N. V. Schizas. 2020. Recent and historical explorations of the underwater section of Cueva del Agua, Punta Los Ingleses, Mona Island (Puerto Rico), with a new faunal record. Life: The Excitement of Biology 8(1):4-22.

Olson, S. L. 1974. A new species of Nesotrochis from Hispaniola, with notes on other fossil rails from the West Indies (Aves: Rallidae). Proceedings of the Biological Society of Washington 38:439-450.

Olson, S. L. 1976. A new species of Milvago from Hispaniola, with notes on other fossil caracaras from the West Indies (Aves: Falconiformes). Proceedings of the Biological Society of Washington 88:355-366.

Olson, S. L. 1976. Fossil woodcocks: an extinct species from Puerto Rico and an invalid species from Malta (Aves:Scolopacidae: Scolopax). Biological Society of Washington, Proceedings 89(20):265-274.

Olson, S. L. 1977. Pleistocene birds from Puerto Rico. National Geographic Society Research Reports. 1977 Projects:563-565.

Olson, S. L. 1982. A new species of palm swift (Tachornis: Apodidae) from the Pleistocene of Puerto Rico. The Auk 99:230-235.

Olson, S. L. 2015. History, morphology, and fossil record of the extinct Puerto Rican parakeet Psittacara maugei Souancé. The Wilson Journal of Ornithology 127(1):1-12.

Olson, S. L. and E. J. Maíz López. 2008. New evidence of Ara autochthones from an archeological site in Puerto Rico: a valid species of West Indian macaw of unknown geographic origin (Aves: Psittacidae). Caribbean Journal of Science 44(2):215-222.

Olson, S. L. and M. C. McKitrick. 1981. A new genus and species of emberizine finch from Pleistocene cave deposits in Puerto Rico (Aves: Passeriformes). Journal of Vertebrate Paleontology 1(3/4):279-283.

Olson, S. L. and Á. M. Nieves-Rivera. 2010. Fossil evidence and probable extinction of the greater fishing bat Noctilio leporinus (Chiroptera: Noctilionidae) on Isla de Mona, Puerto Rico. Mastozoología Neotropical 17(1):167-170.

Ortega-Ariza, D., E. K. Franseen, and M. K. Boudagher-Fadel. 2021. Effects of sea level and upwelling on development of a Miocene shallow-water tropical carbonate ramp system, Ponce, Puerto Rico. Journal of Sedimentary Research 91:1227–1256.

Ortega-Ariza, D., E. K. Franseen, H. Santos-Mercado, W. R. Ramírez-Martínez, and E. E. Core-Suárez. 2015. Strontium isotope stratigraphy for Oligocene-Miocene carbonate systems in Puerto Rico and the Dominican Republic: implications for Caribbean processes affecting depositional history. Journal of Geology 123:539-560.

Panuska, B. C., J. M. Mylroie, D. Armentrout, and B. McFarlane. 1998. Magnetostratigraphy of Cueva del Aleman, Isla de Mona, Puerto Rico and the species duration of Audubon's shearwater. Journal of Cave and Karst Studies 60:96-100.

Pearson, P. N. and B. S. Wade. 2009. Taxonomy and stable isotope paleoecology of well-preserved planktonic foraminifera from the uppermost Oligocene of Trinidad. Journal of Foraminiferal Research 39(3):191-217.

Pessagno, E. A., Jr. 1960. Stratigraphy and micropaleontology of the Cretaceous and lower Tertiary of Puerto Rico. Micropaleontology 6(1):87-110.

Pessagno, E. A., Jr. 1961. The micropaleontology and biostratigraphy of the middle Eocene Jacaguas group, Puerto Rico. Micropaleontology 7:351–358.

Pessagno, E. A., Jr. 1962. The Upper Cretaceous stratigraphy and micropaleontology of south-central Puerto Rico. Micropaleontology 8(3):349-368.

Pessagno, E. A., Jr. 1963. Planktonic Foraminifera from the Juana Diaz Formation, Puerto Rico. Micropaleontology 9(1):53-60.

Pessagno, E. A., Jr. 1963. Upper Cretaceous Radiolaria from Puerto Rico. Micropaleontology 9(2):197-214.

Pisera, A., M. Martínez and H. Santos. 2006. Late Cretaceous siliceous sponges from El Rayo Formation, Puerto Rico. Journal of Paleontology 80(3):594-600.

Pregill, G. K. 1981. Late Pleistocene herpetofaunas from Puerto Rico. University of Kansas Museum of Natural History, Miscellaneous Publications 71:1-72.

Pregill, G. K., and S. L. Olson. 1981. Zoogeography of West Indian Vertebrates in relation to Pleistocene climatic cycles. Annual Review of Ecology and Systematics 12:75-98.

Rabell-Cabrero, N. 1914. Notas paleontológicas. Revista de las Antillas 2(1):66-69.

Rabell-Cabrero, N. 1924. Notas sobre algunos escuálidos fósiles de Puerto Rico. Revista Agricultura de Puerto Rico 12:377-384.

Ray, C. E. 1964. The taxonomic status of Heptaxodon and dental ontogeny in Elasmodontomys and Amblyrhiza (Rodentia: Caviomorpha). Bulletin of the Museum of Comparative Zoology 131(5):107-127.

Reinhart, R. H. 1959. A review of the Sirenia and Desmostylia. University of California Publications in Geological Sciences 36(1):1-146.

Reynolds, T. E., K. F. Koopman, and E. E. Williams. 1953. A cave faunule from western Puerto Rico with a discussion of the genus Isolobodon. Breviora 12:1–8.

Sachs, K. N., Jr. 1959. Puerto Rican upper Oligocene larger Foraminifera. Bulletin of American Paleontology 39:399-416.

Sachs, K. N., Jr. 1964. Multilocular embryonts in Lepidocyclina (Eulepidina) undosa Cushman from Puerto Rico. Micropalaeontology 10:323-329.

Sachs, K. N., Jr., and W. A. Gordon. 1962. Stratigraphic distribution of middle Tertiary larger Foraminifera from southern Puerto Rico. Bulletins of American Paleontology 44:5-24.

Schweitzer, C. E., M. A. Iturralde-Vinent, J. L. Hetler and J. Velez-Juarbe. 2006. Oligocene and Miocene Decapods (Thalassinidea and Brachyura) from the Caribbean. Annals of the Carnegie Museum of Natural History 75(2):111-136.

Schweitzer, C. E., J. Velez-Juarbe, M. Martinez, A. Collmar Hull, R. M. Feldmann and H. Santos. 2008. New Cretaceous and Cenozoic decapoda (Crustacea: Thalassinidea, Brachyura) from Puerto Rico, United States Territory. Bulletin of the Mizunami Fossil Museum 34:1-15.

Seiglie, G. A. 1972. A new genus and species of foraminifera from the Tertiary of Puerto Rico. Caribbean Journal of Science 12:115–118.

Seiglie, G. A. 1973. Revision of mid-Tertiary stratigraphy of southwestern Puerto Rico. Bulletin of the American Association of Petroleum Geologists 57:405–406.

Seiglie, G. A., and P. J. Bermúdez. 1969. Informe preliminar sobre los foraminíferos del Terciario del sur de Puerto Rico. Caribbean Journal of Science 9:67-80.

Seiglie, G. A., and M. T. Moussa. 1976. Smaller benthic foraminifera and correlation of the Oligocene-Pliocene rocks in Puerto Rico. Caribbean Geological Conference Transactions 7:255–262.

Seiglie, G. A., K. Grove, and J. A. Rivera. 1976. Revision of some Caribbean Archaiasinae, new genera, species and subspecies. Ecologiae Geologicae Halvetiae 70:855–883.

Sohl, N. F. 1987. Cretaceous gastropods: contrasts between Tethys and the temperate provinces. Journal of Paleontology 61(6):1085–1111.

Sohl, N. F. 1992. Upper Cretaceous gastropods (Fissurellidae, Haliotidae, Scissurellidae) from Puerto Rico and Jamaica. Journal of Paleontology 66(3):414-434.

Sohl, N. F. 1998. Upper Cretaceous trochacean gastropods from Puerto Rico and Jamaica. Palaeontographica Americana 60:1-109.

Sohl, N. F., and H. A. Kollmann. 1985. Cretaceous actaeonellid gastropods from the Western Hemisphere. U.S. Geological Survey Professional Paper 1304:1–104.

Soto-Centeno, J. A., and D. W. Steadman. 2015. Fossils reject climate change as the cause of extinction of Caribbean bats. Scientific Reports 5:7971.

Smith, A. G., N. F. Sohl, and E. L. Yochelson. 1968. New upper Cretaceous Amphineura (Mollusca). U.S. Geological Survey Professional Paper 593-G:1–9.

Todd, R., and D. Low. 1976. Smaller Foraminifera from deep wells on Puerto Rico and St. Croix. U.S. Geological Survey Professional Paper 863:1–32.

Turvey, S. T. 2010. Evolution of non-homologous venom delivery systems in West Indian insectivores? Journal of Vertebrate Paleontology 30(4):1294-1299.

Turvey, S. T., F. V. Grady and P. Rye. 2006. A new genus and species of ‘giant hutia’ (Tainotherium valei) from the Quaternary of Puerto Rico: an extinct arboreal quadruped? Journal of Zoology 270:585-594.

Turvey, S. T., J. R. Oliver, Y. M. Narganes Storde and P. Rye. 2007. Late Holocene extinction of Puerto Rican native land mammals. Biology Letters 3:193-196.

van den Bold, W. A. 1965. Middle Tertiary Ostracoda from Northwestern Puerto Rico. Micropaleontology 11(4):381-414.

van den Bold, W. A. 1969. Neogene Ostracoda from southern Puerto Rico: Caribbean Journal of Science 9:117-133.

van den Bold, W. A. 1975. Remarks on Ostracode-bioestratigraphy of the late and middle Tertiary of southwest Puerto Rico. Caribbean Journal of Science 15:31-40.

Vaughan, T. W. 1919. Fossil corals from Central America, Cuba, and Porto Rico, with an account of the American Tertiary, Pleistocene, and recent coral reefs. US National Museum Bulletin 103:189-524.

Velez-Juarbe, J. 2014. Ghost of seagrasses past: using sirenians as a proxy for historical distribution of seagrasses. Palaeogeography, Palaeoclimatology, Palaeoecology 400:41-49.

Velez-Juarbe, J., and D. P. Domning. 2014. Fossil Sirenia of the West Atlantic and Caribbean region: X. Priscosiren atlantica, gen. et sp. nov. Journal of Vertebrate Paleontology 34:951-964. 

Velez-Juarbe, J. and D. P. Domning. 2015. Fossil Sirenia of the West Atlantic and Caribbean region: XI. Callistosiren boriquensis, gen. et sp. nov. Journal of Vertebrate Paleontology 35(1):e885034.

Velez-Juarbe, J. and T. E. Miller. 2007. First report of a Quaternary Crocodylian from a cave deposit in Northern Puerto Rico. Caribbean Journal of Science 43(2):273-277.

Velez-Juarbe, J. and H. Santos. 2008. Fossil Echinodermata from Puerto Rico; pp. 369-395 in W. I. Ausich and G. D. Webster (eds.), Echinoderm Paleobiology. Indiana University Press, Bloomington, Indiana.

Velez-Juarbe, J., C. A. Brochu and H. Santos. 2007. A gharial from the Oligocene of Puerto Rico: transoceanic dispersal in the history of a nonmarine reptile. Proceedings of the Royal Society B, 274:1245-1254.

Velez-Juarbe, J., T. Martin, R. D. E. MacPhee, and D. Ortega-Ariza. 2014. The earliest Caribbean rodents: Oligocene caviomorphs from Puerto Rico. Journal of Vertebrate Paleontology 34:157-163.

Vokes, H. E., and E. H. Vokes. 1968. Variation in the genus Orthaulax (Mollusca: Gastropoda). Tulane Studies in Geology and Paleontology 6:71–84.

Wetmore, A. 1920. Five new species of birds from cave deposits in Porto Rico. Biological Society of Washington, Proceedings 33:76-81.

Wetmore, A. 1922. Bird remains from the caves of Porto Rico. Bulletin of the American Museum of Natural History 46:297-333.

Wetmore, A. 1927a. Birds of Porto Rico and the Virgin Islands—Colymbiformes to Columbiformes. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands IX:245–406.

Wetmore, A. 1927b. Birds of Porto Rico and the Virgin Islands—Psittaciformes to Passeriformes. New York Academy of Sciences, Scientific Survey of Porto Rico and the Virgin Islands IX:409–571.

Wetmore, A. 1937. Ancient records of birds from the island of St. Croix with observations on extinct and living birds of Puerto Rico. Journal of Agriculture of the University of Puerto Rico 21(1):5–16.

Whidden, H. P. and R. J. Asher. 2001. The origins of the Greater Antillean Insectivorans; pp. 237-252 in C. A. Woods and F. E. Sergile (eds.), Biogeography of the West Indies: Patterns and Perspectives, Second Edition. CRC Press, Boca Raton, Florida. 

White, J. L., and R. D. E. MacPhee. 2001. The sloths of the West Indies: A Systematic and Phylogenetic Review; pp. 201-235 in C. A. Woods and F. E. Sergile (eds.), Biogeography of the West Indies: Patterns and Perspectives, Second Edition. CRC Press, Boca Raton, Florida.

Williams, E. E. 1952. A new fossil tortoise from Mona Island, West Indies and a tentative arrangement of the tortoises of the world. Bulletin of the American Museum of Natural History 99(9):541-560.

Williams, E. E. and K. F. Koopman. 1951. New fossil rodent from Puerto Rico. American Museum Novitates 1515:1-9.

Wood, R. C. 1972. A fossil pelomedusid turtle from Puerto Rico. Breviora 392:1-13.

Woods, C. A. 1996. The land mammals of Puerto Rico and the Virgin Islands. Annals of the New York Academy of Sciences 776:131-149.

Woods, C. A., R. Borroto Paéz, and C. W. Kilpatrick. 2001. Insular Patterns and Radiations of West Indian Rodents; pp. 335-353 in C. A. Woods and F. E. Sergile (eds.), Biogeography of the West Indies: Patterns and Perspectives, Second Edition. CRC Press, Boca Raton, Florida.

Woods, R., I. Barnes, S. Brace, and S. T. Turvey. 2021. Ancient DNA suggests single colonization and within-Archipelago diversification of Caribbean caviomorph rodents. Molecular Biology and Evolution 38:84-95.

Young, K. 1977. Cretaceous (Albian) ammonites from Puerto Rico and St. Thomas. Texas Journal of Science 29:263–277.

Zimmerman, A. N., C. C. Johnson, G. E. Phillips, and D. J. Ehret. 2023. Taxonomy and paleobiogeography of rudist bivalves from Upper Cretaceous strata, Gulf Coastal Plain and Puerto Rico, USA. Journal of Paleontology 97(2):318–340.