Saber-toothed cat

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The fossilized skeleton of a saber-toothed cat (Smilodon californicus).

The terms saber-toothed cat, sabertooth, and saber-toothed tiger describe numerous species, mainly in the families Felidae (subfamily Machairodontinae), Hyaenodontidae, and Nimravidae, but also including two marsupial families, that lived during various parts of the Cenozoic Era and evolved their saber-toothed characteristics entirely independently. They are most known for having maxillary canines which were, in some species, up to 20 cm long and extended down from the mouth even when the mouth was closed. Saber-tooth cats were generally more robust than today's cats and were quite bear-like in build.

1 Saber-tooth genera
2 Saber-tooth evolutionary tree
3 External links

[edit] Saber-tooth genera

The first saber-toothed cats appeared sometime during the Mid-Eocene, and the last genera died out thousands of years ago. The genera of saber-toothed cats, along with the regions and time periods where they have been found, is summarized here.

Genus Name	Species	Appeared	Died out	Regions	Canine Size
Smilodon	6	02.5 2.5 MYA	0.008 8,000 YA	North & South America	17-20cm
Hoplophoneus	5	33.7 MYA	23.8 MYA	North & South America
Eusmilis	3	30.5 MYA	28 MYA	Europe, North & South America
Dinictis	4	40 MYA	25 MYA	North America
Dinaelurus	1	?	?	North America
Dinailurictis	1	?	?	?
Eofelis	1	?	?	?
Nimravidus (Nimravides)	2	?	?	?
Nimravus (Nimravinus)	6	33.5 MYA	20 MYA	Europe, North America
Nimraviscus	1	?	?	?
Pogonodon	2	15 MYA	06 6 MYA	Europe, North America
Quercylurus	1	?	?	?
Archaelurus	1	?	?	?
Aelurogale (Ailurictis)	1	?	?	?
Ictidailurus	1	?	?	?
Albanosmilus	3	18 MYA	03 3 MYA	Africa, Eurasia
Afrosmilus	1	25 MYA	10 MYA	Africa
Barbourofelis	7	15 MYA	03 3 MYA	Africa, Eurasia
Ginsburgsmilus	1	23 MYA	10 MYA	Africa
Prosansanosmilus	2	18 MYA	05 5 MYA	Africa, Eurasia
Sansanosmilus	3	12 MYA	03 3 MYA	Africa, Eurasia
Syrtosmilus	1	23 MYA	08 8 MYA	Africa
Vampyrictis	1	15 MYA	03 3 MYA	Africa, Eurasia
Vishnusmilus	1	?	?	?
Homotherium	10	03 3 MYA	0.01 10,000 YA	Africa, Eurasia, North America
Thylacosmilus (marsupial)	2	10 MYA	01.8 1.8 MYA	South America	30+cm
Metailurus	9	15 MYA	08 8 MYA	Eurasia
Adelphailurus	1	23 MYA	05 5 MYA	North America (Kansas)
Paramachairodus	3	20–15 MYA	09 9 MYA	Europe
Machairodus (Ancestral to Homotherium)	18	15 MYA	02 2 MYA	Africa, Eurasia, North America
Megantereon	8	03 3 MYA	0.5 0.5 MYA	Africa, Eurasia, North America
Dinofelis	6	05 5 MYA	01.5 1.5 MYA	Africa, Eurasia, North America
Pontosmilus	4	20 MYA	09 9 MYA	Eurasia
Xenosmilus (1 specimen)	1	01.7 1.7 MYA	01 1 MYA	North America (Florida)
Stenailurus	1	?	?	?
Epimachairodus	1	?	?	?
Miomachairodus	1	?	?	?
Hemimachairodus	1	?	?	?
Ischyrosmilus	1	?	?	?

[edit] Saber-tooth evolutionary tree

A statue of two saber-tooth cats fighting

Saber-Tooth model display in the La Brea Tar Pits Museum.

All saber-tooth mammals lived between 33.7 million and 9,000 years ago, but the evolutionary lines that lead to the various saber-tooth genera started to diverge much earlier.

The lineage that led to Thylacosmilus was the first to split off, in the late Cretaceous. It is a marsupial, and thus more closely related to kangaroos and opossums than the felines. The creodonts diverged next, and then the nimravids, before the blossoming of the truly feline saber-tooths.

Class Mammalia
- Subclass Marsupialia (diverged ? MYA, in the Cretaceous)
  - Order †Sparassodonta (an extinct group of marsupial carnivores)
    - Family †Borhyaenidae
    - Family †Thylacosmilidae
      - †Thylacosmilus
- Subclass Placentalia
  - Order †Creodonta (diverged ? MYA, in the Paleocene)
    - Family †Hyaenodontidae
      - †Hyaenodon
      - †Boualitomus
      - †Laekitherium
      - †Metapterodon
      - †Triacodon
      - †Parvagula
  - Order Carnivora
    - Family †Nimravidae (diverged from the feliforms 48–55 MYA, in the late Eocene)
      - Subfamily †Nimravinae (Dinictis)
      - Subfamily †Hoplophoninae
    - Suborder Feliformia ('cat-like' carnivores)
      - Family †Barbourofelidae (sister taxa to Felidae)
      - Family Felidae (true cats)
        
        Subfamily †Machairodontinae (diverged ? MYA, in the ?)
        
        Tribe †Homotheriini
        
        †Homotherium
        
        †Machairodus
        
        †Xenosmilus
        
        Tribe †Metailurini
        
        †Dinofelis
        
        †Metailurus
        
        Tribe †Smilodontini
        
        †Megantereon
        
        †Paramachairodus
        
        †Smilodon