Megalictis

{{Short description|Extinct genus of carnivores}} {{Automatic taxobox | fossil_range = Early Miocene, {{fossilrange|22.7|18.5}} | image = Megalictis skull.PNG | image_caption = Skull AM 25430 of ''M. ferox'' | taxon = Megalictis | authority = | subdivision_ranks = Species | subdivision = * ''M. ferox'' Matthew, 1907 * ''M. frazieri'' * ''M. petersoni'' | synonyms = * ''Aelurocyon'' * ''Paroligobunis'' }}

'''''Megalictis''''' (meaning "great weasel") is an extinct genus of large predatory mustelids that existed in North America during the "cat gap" from the Late Arikareean (Ar4) in the Miocene epoch. It is thought to have resembled a huge, jaguar-sized ferret, weighing up to {{convert|60|-|100|kg|lb}}.<ref>{{cite book|first1=David W.|last1=Macdonald|first2=Chris|last2=Newman|chapter=6 – Musteloid sociality: the grass-roots of society|editor1=Macdonald, David W.|editor2=Newman, Chris|editor3=Harrington, Lauren A.|year=2017|title=Biology and Conservation of Musteloids|publisher=Oxford University Press|pages=167–188|doi=10.1093/oso/9780198759805.003.0006}}</ref>

==History of discovery== [[File:Megalictis frazieri FLMNH.jpg|left|thumb|''M. frazieri'' jaw, Florida Museum of Natural History]] The genus ''Megalictis'' was first described by W. D. Matthew in 1907, and assigned to the family Mustelidae.<ref name="PaleobiologyDatabase">Paleobiology Database</ref> Two similar genera discovered at the same time, ''Aelurocyon'' (Peterson, 1907) and ''Paroligobunis'' (Peterson, 1910) were identified as synonymous with ''Megalictis'' in 1996<ref name="Andersson">Andersson, p.39</ref> though ''Paroligobunis'' was re-established as a separate genus in 1998.<ref name=PDB>{{cite web |url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=41128 |title=''Megalictis'' at the Paleobiology Database. |publisher=paleodb.org |access-date=2008-11-25}}</ref> P. R. Bjork, in 1970, assigned the genus to the subfamily Mellivorinae,<ref>Bjork, p.18</ref> whilst J. A. Baskin reassigned it to Oligobuninae in 1998.<ref name="PaleobiologyDatabase" /> Three species have been identified in the genus: ''M. ferox'', ''M. petersoni'', and ''M. frazieri'', whilst two more, ''Megalictis brevifacies'' and ''Megalictis simplicidens'', have since been determined to be synonymous with ''M. ferox''. Other synonyms of ''M. ferox'' include ''Aelurocyon brevifacies'', ''Brachypsalis simplicidens'' and ''Paroligobunis simplicidens''.<ref name="PaleobiologyDatabase" />

Specimens of ''M. ferox'' have been found at ten sites in South Dakota, Nebraska and Wyoming, dated to the Harrisonian period - from 24.8 to 20.6 million years ago.<ref name="PaleobiologyDatabase" /> The 19 specimens so far identified have a wide range of sizes,<ref name="Andersson" /> which is believed to be evidence of extreme sexual dimorphism, a phenomenon where males and females of the species will grow to different sizes; a 1996 study rejected the possibility of multiple "morphologically uniform" but differently sized species as unlikely.<ref>Hunt & Skolnick, quoted Andersson, p.39-40</ref> However, later studies identified significant morphological variation in the joints of the forearms, which would not be consistent with sexual dimorphism. Andersson suggests that the identification of all of these as a single species may need revision.<ref>Andersson, p.11 & p.40</ref>

==Description== thumb|upright|left|Life restoration, reconstructed skull, and skull AM 25430 of ''M. ferox'' ''Megalictis'' was one of the largest terrestrial mustelids ever recorded, surpassing in size other mustelids like ''Ekorus'', ''Eomellivora'', and ''Plesiogulo''.<ref name=Valenciano2016>{{Cite journal|last1=Valenciano|first1=Alberto|last2=Baskin|first2=Jon A.|last3=Abella|first3=Juan|last4=Pérez-Ramos|first4=Alejandro|last5=Álvarez-Sierra|first5=M. Ángeles|last6=Morales|first6=Jorge|last7=Hartstone-Rose|first7=Adam|date=2016-04-07|title=''Megalictis'', the Bone-Crushing Giant Mustelid (Carnivora, Mustelidae, Oligobuninae) from the Early Miocene of North America|journal=PLOS ONE|language=en|volume=11|issue=4|article-number=e0152430|doi=10.1371/journal.pone.0152430|issn=1932-6203|pmc=4824437|pmid=27054570|doi-access=free }}</ref> Recovered skulls of ''Megalictis ferox'' had similar condylobasal lengths to small modern jaguars, ranging from {{cvt|189.5 to 241.1|mm|in}} in length, and were almost as wide in mastoid width as those of some black bears, ranging from {{cvt|106.1 to 136|mm|in}} wide. The enlarged anterior edge of the coronoid process confers a wide gape relative to its short rostral length, suggesting ''Megalictis'' possessed a powerful bite force; together with blunt, stout postcanine teeth, ''Megalictis'' was well equipped to engage in osteophagy, similar to modern hyenas and wolverines.<ref name=Valenciano2016/> It has been described as having short stout legs, with short feet and long non-retractible claws, similar to a modern ferret but about twice the size,<ref name="Andersson" /> and noted that "the teeth indicate an animal fully as predaceous as the wolverine, but the skeleton points to more fossorial habits".<ref>Quoted in Gratacap, p.921</ref> Research comparing the joints of the forelegs to modern mammalian carnivores suggests that it waited in ambush and grappled with its prey, rather than hunting it down by pursuit like a modern cheetah.<ref>Hopkin</ref>

==References==

===Sources===

*{{cite book|last=Andersson|first=Ki|title=Locomotor evolution in the Carnivora (Mammalia): evidence from the elbow joint|year=2003|url=http://www.carnivoreconservation.org/files/thesis/anderson_2003_msc.pdf}} *{{cite journal|last=Bjork|first=Philip Reese|year=1970|title=The Carnivora of the Hagerman Local Fauna (Late Pliocene) of Southwestern Idaho|journal=Transactions of the American Philosophical Society|volume=60|issue=7|pages=3–54|doi=10.2307/1006119|jstor=1006119}} * {{cite journal | last1 = Valenciano | first = Alberto | last2 = Baskin | first2 = Jon A. | last3 = Abella | first3 = Juan | last4 = Pérez-Ramos | first4 = Alejandro | last5 = Álvarez-Sierra | first5 = M. Ángeles | last6 = Morales | first6 = Jorge | last7 = Hartstone-Rose | first7 = Adam | date = 7 April 2016 | title = ''Megalictis'', the bone-crushing giant mustelid (Carnivora, Mustelidae, Oligobuninae) from the Early Miocene of North America | journal = PLOS ONE | doi = 10.1371/journal.pone.0152430 | volume=11 | issue = 4 | article-number=e0152430 | pmid=27054570 | pmc=4824437| bibcode = 2016PLoSO..1152430V | doi-access = free }} *{{cite book|editor=Allaby, Michael|title=A Dictionary of Zoology|publisher=Oxford University Press|location=Oxford|year=1999}} *{{cite journal|last=Gratacap|first=L. P.|date=June 12, 1908|title=Scientific Publications of the American Museum of Natural History for 1907|journal=Science|volume=27|issue=702 | doi=10.1126/science.27.702.920 |pages=920–923|bibcode=1908Sci....27..920G|url=https://zenodo.org/record/1448004}} *{{cite journal|last=Hopkin|first=Michael|date=30 September 2004|title=Research highlights: elbow room for top predators|journal=Nature|volume=431|issue=7008|page=524|doi=10.1038/431524a|doi-access=free}} *{{cite journal|last1=Hunt |first1=R. H. Jr. |last2=Skolnick |first2=R.|year=1996|title=The giant mustelid Megalictis from the Early Miocene carnivore dens at Agate Fossil Beds National Monument, earliest evidence of dimorphism in New World Mustelidae|journal=Contributions to Geology|issue=31|pages=35–48}} *{{cite web |url=https://paleobiodb.org/classic/checkTaxonInfo?taxon_no=48009 |title=''Megalictis ferox'' at the Paleobiology Database. |publisher=paleodb.org |access-date=2008-11-25}}

Category:Prehistoric mustelids Category:Miocene mustelids Category:Miocene mammals of North America Category:White River Fauna Category:Fossil taxa described in 1907 Category:Prehistoric carnivoran genera