Giant Beaver: Two Species to Choose From

By Charles R. Knight [Public domain], via Wikimedia Commons
By Charles R. Knight [Public domain], via Wikimedia Commons
There’s no type of extinct mammalian megafauna we like better than the giant beaver. Most specimens of the giant beaver, an extinct Pleistocene rodent found throughout North America that approached the size of a black bear, are considered Castoroides ohioensis. Now, scientists have proposed a new species of giant beaver, Castoroides dilophidus, based on skulls found in Florida.

This new species lived during the Late Pleistocene and is limited, so far, to Florida and surrounding states. It is distinguished from C. ohioensis by several cranial characteristics as well as the presence of a divided lophid on two teeth, the lower fourth premolar and upper third molar (hence the species name dilophidus). An earlier named species, C. leiseyorum, thought to be restricted to the Early Pleistocene, is now also subsumed into C. dilophidus as a junior synonym.

Some interesting issues regarding the collection and curation of fossils pop up. One of the skulls used to define the new species “is housed in a private collection, but a high fidelity cast is in the UF [University of Florida] collection. Furthermore, the owner of the original specimen has agreed to make it available for study to other workers.” (Hulbert et al. 2014:29). The owner is unnamed. They also discuss in detail casts of a giant beaver skull sold by the company Bone Clones that “likely reside in a number of museum collections” (Hulbert et al. 2014:38). This specimen, which the company labels C. ohioensis, also has characteristics of C. dilophidus. It appears that the original fossil has dilophidus traits, but when the fossil was restored, missing parts were reconstructed using ohioensis (and modern beaver) as references. Hulbert and colleagues were able to solve this puzzle by speaking with the original collector and the person who did the restoration, both of whom are unnamed, but the actual fossil “is now in a private collection and not available for study.” (Hulbert et al. 2014:38). The authors have tried to make the best of an awkward situation by documenting as thoroughly as possible these mystery fossils.



Hulbert, Richard C., Jr., Andreas Kerner, and Gary S. Morgan

2014       Taxonomy of the Pleistocene Giant Beaver Castoroides (Rodentia: Castoridae) From the Southeastern United States. Bulletin of the Florida Museum of Natural History 53(2):26–43.


Fossil Mammal Names Inspired by J.R.R. Tolkien: The Etymologies

"I Am No Condylarth!" Art by the Brothers Hildebrandt
“I Am No Condylarth!” Art by the Brothers Hildebrandt

Figured out the Lord of the Rings and other Middle Earth references encoded in the scientific names of these fossil condylarths? Here is Leigh Van Valen’s original explanation of how he came up with the names. Impressive how he managed to mix in allusions to Greek, English, and Egyptian meanings for some of the names.

Oxyprimus galadrielae “Galadriel (Sindarin [Elvish], radiantly garlanded woman), wise elf-queen of the Lord of the Rings and The Silmarillion.”

Protungulatum gorgun “Gorgûn, the Woses’ name for orcs in the Lord of the Rings”

Deltatherium durini “Name of many dwarf-kings in The Lord of the Rings; Durin I began Khazad-Dûm. Allusion is to size”

Chriacus calenancus “Sindarin (Elvish) calen, green; anca, jaws. Reference is to inferred herbivory.”

Thangorodrim thalion Genus from “Thangorodrim, the mountainous triple fortress of Morgoth in The Silrnarillion. Reference is to Purgatory Hill.” [the site where the fossil was collected]. Species name “Sindarin (Elvish) thalion, strong. Reference is to the massive morphology and the generic name.”

Arctocyonides [Claenodon] mumak “Mûmak, name used in Ithilien for the animal hobbits called an oliphaunt, resembling a large elephant. Reference is to size.”

Platymastus palantir “Quenya (Elvish) palantir, distant watcher, one of 7 globes made by Fëanor that gave visions through spacetime. Reference is to the long duration of the genus.”

Platymastus [Aletodon] mellon “Sindarin (Elvish) mellon, friend, the password of the west gate of Khazad-dûm in The Lord of the Rings. Reference is to similarlty to P. palantir, presumptive diet of plants, and obliquely to the English word melon and Greek mellesis, delay, from mello.”

Mimotricentes mirielae “Míriel (Quenya, Jewel-woman), Númenorian queen in The Silmarillion, forced into marriage and the loss of her throne.”

Desmatoclaenus mearae “Meara, any one of the great horses of Rohan in The Lord of the Rings.”

Deuterogonodon noletil “Quenya (Elvish) nólë, knowledge, and til, horn. Reference is to the apparent relationship of D. noletil to uintatheres.”

Litaletes ondolinde “Quenya (elvish) ondo, rock, and lindë, song. Reference is to Rock Bench and to the hidden city Ondolindë or Gondolin of The Silmarillion. The Rock Bench specimens and others were formerly as hidden (and unsorted).”

Bomburia “Bombur, a fat dwarf in The Hobbit and The Lord of the Rings. Reference is to size and morphology.”

Protoselene bombadili “Tom Bombadil, the Hobbit name for a simple, powerful, and very old being. Reference is to these three traits.”

Litomylus (?) alphamon Sindarin (Elvish) alph, swan, and amon, hill. Reference is to the locality [Swan Hill], with allusion also to Alph, the sacred river of Xanadu; Amon, usually the Chief Egyptian god; alpha, the letter; and Greek monos, single.”

Maiorana noctiluca Maiorana is derived from Middle Latin maiorana, marjoram, with allusion to Latin decompositions as larger or May frog, and things pertaining to the larger, or to the gold of Maia or May. Quenya (Elvish), wandering angel. Allusion is to the pleasantly splcy Maiorana family.”

Tinuviel eurydice Sindarin (Elvish) tinúviel, daughter of twilight, or nightingale, Beren’s name for Lúthien in The Silmarillion. Eurydice: Eurydice vanished just before being led from Hades. Reference is to Purgatory Hill [the site where the fossil was collected], the late occurrence of this species, Lúthien’s rescue of Beren from Sauron’s dungeon, and their escape from Morgoth’s deep tunnels with a silmaril.

Fimbrethil ambaronae “Fimbrethil, entwife loved by Fangorn in The Lord of the Rings. Reference is to partly primate-like morphology and the disappearance of both Fimbrethils.” Quenya (Elvish) ambarona, one of Fangorn’s shorter names for his forest. Reference is to the dimness of the forest and of the affinities of this species.”

Mimatuta morgoth Mimatuta: “Sindarin (Elvish) mir, jewel, and Matuta, Roman goddess of dawn. Reference is to ancestral position, with allusion to Latin mius, imitator, and tuta, safe, and to Mim, dwarf of The Silmarillion, and Latin tuta, examined.” Morgoth (Quenya [Elvish] mor, dark, and goth, universal enemy). Fëanor’s name for Melkor, the power-lustful Vala of The Silmarillion. Reference is to the Hell Creek Formation.”

Mimatuta minuial Sindarin (Elvish) minuial, the time at dawn when the stars fade. Reference is to the dawn of the Cenozoic and the fading of the Mesozoic stars.”

Earendil undomiel “Eärendil [father of Elrond], who, (in the Silmarillion) sailed with a silmaril to get the aid that defeated Morgoth.” Quenya (Elvish), undómiel, evening star, which Eärendil with his silmaril became.”

Anisonchus athelas (later synonymized with Anisonchus eowynae) Sindarin (Elvish) athelas, kingsfoil, a healing plant in The Lord of the Rings. Reference is to the joining of phylogenies.”

Anisonchus eowynae Éowyn, woman of Rohan in The Lord of the Rings, who killed the chief of the Nazgûl and was cured of his poison by athelas.

Mithrandir Mithrandir (Sindarin, gray wanderer), elvish name for Olorin [i.e., Gandalf] wisest of the Istari in The Lord of the Rings. Reference is to the subtleness of the differences between the subgenera.”

Ancalagon “The mightiest dragon of Morgoth, in the Silmarillion.”

Niphredil radagasti “Sindarin (Elvish) niphredil, white-flowering forb of open woods in Neldoreth and Lothlorien.” and “Radagast, naturalist of the Istari in The Lord of the Rings.”


L. M. Van Valen. 1978. The beginning of the Age of Mammals. Evolutionary Theory 4:45-80


One giant crocodile fossil with a Tolkien name? How about 26 small mammals?

Giant condylarths prior to becoming fossilized. Or not.

University of Florida scientists have name a newly discovered extinct crocodile Anthracosuchus balrogus, after the Tolkien’s Balrog, defeated by Gandalf in the Mines of Moria.

Name one new species after a character from the Lord of the Rings? Big deal. For Leigh Van Valen, evolutionary biologist, longtime University of Chicago professor, and intellectual eccentric, Tolkien was the inspiration for over two dozen species named after people, places, and things in Middle Earth.

In 1978, long before the Peter Jackson movies, Van Valen described 26 newly recognized early mammal species based on fossils (almost exclusively teeth) from Montana and Wyoming belonging to a group known as condylarths, considered the ancestors of ungulates, the hoofed mammals. They date from the Paleocene epoch (as does A. balrogus), the time just after the extinction of the dinosaurs.

Van Valen put some serious thought into these names. For example,  the name Thangorodrim thalion was derived from “Thangorodrim, the mountainous triple fortress of Morgoth in The Silmarillion. Reference is to Purgatory Hill.” [the site where the fossil was collected]. Species name “Sindarin (Elvish) thalion, strong. Reference is to the massive morphology and the generic name.”

Here are all of them. Can you identify the references? The first one is easy, but they get harder. Better have your Elvish dictionary on hand.  Coming soon will be the answers, as provided by Van Valen himself in the original article [Edit: Find the answers here]:

L. M. Van Valen. 1978. The beginning of the Age of Mammals.  Evolutionary Theory 4:45-80

Oxyprimus galadrielae

Protungulatum gorgun

Deltatherium durini

Chriacus calenancus

Thangorodrim thalion (synonym of Oxyclaenus Cope 1884)

Arctocyonides [Claenodon] mumak

Platymastus palantir

Platymastus [Aletodon] mellon

Mimotricentes mirielae

Desmatoclaenus mearae

Deuterogonodon noletil

Litaletes ondolinde

Bomburia (New genus, later reassigned)

Protoselene bombadili [reassigned to Bubogonia bombadili  Williamson 1996]

Litomylus (?) alphamon

Maiorana noctiluca

Tinuviel eurydice

Fimbrethil ambaronae  (Oxyacodon agapetillus (Cope 1884))

Mimatuta morgoth

Mimatuta minuial

Earendil undomiel

Anisonchus athelas

Anisonchus eowynae

Mithrandir  (New subgenus of Anisonchus)

Ancalagon (New genus later renamed Ankalagon Van Valen, 1980 because the original genus name was preoccupied a Cambrian priapulid, Ancalagon Conway Morris, 1977. No, Van Valen was not the first scientist to have read the Lord of the Rings.)

Niphredil radagasti (an insectivoran now in the genus Paleotomus)

Incidentally, Tolkien wasn’t the only fantasy author he read. Van Valen is most famous for the Red Queen hypothesis, which helps explain why evolution occurs. Its name comes from the character in Lewis Carroll’s Through the Looking-Glass, and What Alice Found There.

For more on Leigh Van Valen, read his obituary in the New York Times.

Still want to read about giant extinct crocodiles? See the Anthracosuchus article here:

 A new blunt-snouted dyrosaurid, Anthracosuchus balrogus gen. et sp. nov. (Crocodylomorpha, Mesoeucrocodylia), from the Palaeocene of Colombia