A wide diversity of fossils may be found in Arkansas. The map shows where some of them have been found. Below the map is a list of known Arkansas fossils. It is very much an incomplete list, but it will grow with time. A link is supplied for every fossil which has been discussed in more detail thus far on Paleoaerie. Just click on the name and you will be taken to its description. Most of the descriptions were done as part of a Mystery Monday fossil identification series. You will quickly see that this list is heavily weighted towards vertebrates. That will change as I have more time to delve more deeply into the invertebrates. Partly this is due to the fact that many of our most common fossils are invertebrates which cannot be very closely identified, such as crinoid stems, which can only be identified any further than “crinoid” except possibly by crinoid experts. In those cases, going further into them will not serve the vast majority of people, and as I am not a crinoid expert, I couldn’t do it anyway. The other reason for this bias is that I am more familiar with vertebrate fossils. If anyone who knows a good bit about Arkansas invertebrates and would like to write an article for Paleoaerie, please let me know. Input from other knowledgeable people is always welcomed.
The following list does not precisely follow phylogenetic relationships. It is very simplified, designed to make it easier for nonspecialists to quickly find organisms they are interested in. Perhaps in the future, a phylogenetic map showing more detailed relationships will be added, but that will not be in the foreseeable near future.
If you know of fossils that are not on the list, please contact me and it can be added to the list.
Hexactinellida (glass sponges) – Stioderma hadra
Arachnomorpha – trilobites, other chelicerates
Insecta – Phylloxerids (aphids), Blattodea (cockroaches)
Formicinae (ants) – Protrechina carpenteri
Annelida – Serpula (polychaete)
Bivalvia (clams) – Exogyra ponderosa, Exogyra costata, Gryphaea, Ostrea franklini, Ostrea fulcata, Nuculana
Bryozoa – Archimedes
Hemichordata – Graptolites
Conodont – Gnathodus, Cavusgnathus
Actinopterygii – Lepisosteus, Arius, Trichiurus, Sphyraena, Diaphyodus, Enchodus, Paralbula, Pycnodus, Hadrodus, Stephanodus, Protosphyraena
Testudinata – Prionochelys, Trionychid, Chedighaii, Toxochelys
Crocodylia – Goniopholid
Aves – Hesperornis
Xenarthra – Megalonyx (giant ground sloth), Dasypus (armadillo)
Afrotheria – Mammut (mastodon), Mammuthus (Mammoth)
Glires – Lepus (rabbit), Castor (beaver), Peromyscus, Microtus, Tamiasciurus, Ondatra, Geomys
Chiroptera (bats)– Eptesicus, Myotis
Perissodactyla – Equus (horse)
Soricomorpha – Blarina, Scalopus, Sorex