Palaeogale

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Palaeogale
Temporal range: 33.9–15.97  Ma
Palaeogale skull lateral Matthew 1902.png
Lateral view of Bunaelurus (=Palaeogale) from Matthew 1902
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Suborder: Feliformia
Family: Palaeogalidae
Genus: Palaeogale
von Meyer 1846, p. 474
Species [1]
Synonyms

Palaeogale is an extinct genus of carnivorous mammal known from the Late Eocene, Oligocene, and Early Miocene of North America, Europe, and Eastern Asia. A small carnivore often associated with the mustelids, Palaeogale might have been similar to living genets, civets, and linsangs.

Contents

Time range

The ancestry of Palaeogale remains enigmatic. The genus appears in Europe 32 Ma, after the Grande Coupure, but 35-36 Ma-old (Chadronian NALMA) specimens from Pipestone Springs, Montana, are the oldest known. [2] Palaeogale survived until the late Early Miocene of Europe and the early Early Miocene of East Asia. [3]

Morlo & Nagel 2007 noted that the Palaeogale specimens found in Mongolia are the most plesiomorphic (p1 double-rooted, m2 relatively large, very small overall size) and that the genus probably originated there and migrated to Europe and North America. [3]

Anatomy

Palaeogale was the size of a small mustelid but had a hypercarnivorous dentition and its taxonomic position remains enigmatic. Its dental morphology includes both mustelid (reduced m2) and feliform (slit-like carnassial notch, loss of metaconid on m2, presence of parastyle on P4) features, and Palaeogale is typically placed in Carnivora incertae sedis . [4] [5]

The body mass of Palaeogale sectoria, one of the smallest species, has been estimated to much less than a kilo based on teeth sizes. It was probably semifossorial. [6] P. sanguinarius is slightly larger than P. dorothiae and probably equivalent in age. [5]

Taxonomic history

Mandible of the type species P. minuta, from Schlosser 1888 Palaeogale minuta Schlosser 1888.png
Mandible of the type species P. minuta, from Schlosser 1888

When von Meyer 1846 named the genus Palaeogale and two species (P. pulchella and P. fecunda), he only gave a very vague description of these taxa. Gervais 1848 described a related species, Mustela minuta, which Schlosser 1888 [7] thought identical and named Palaeogale minuta, a name that has remained accepted for the type species. [8]

Inferior view of Bunaelurus (=Palaeogale) from Matthew 1902 Palaeogale skull inferior Matthew 1902.png
Inferior view of Bunaelurus (=Palaeogale) from Matthew 1902

Simpson 1946 wrote that when Cope 1873 described the North American species Bunaelurus lagophagus, he distinguished the genus from the European Plesiogale (=Palaeogale in part) based on differences in M2. Simpson, however, thought this molar was "very closely similar" in both genera and synonymized Cope's genus with Palaeogale. [9] Matthew 1902 described a skull which he referred to Cope's genus "Bunaelurus". The skull was found without lower jaws (on which all Bunaelurus specimens were based), but Matthew argued that the correspondence in horizon and size made the "identification reasonably safe." He nevertheless described it as a "Palaeogale with a minute second molar still retained." [9] [10]

De Bonis' four species [4]
SpeciesTime spanSizeDental morphology
P. sectoriaLate Eocene, Early OligoceneMediumM2 and p1 retained
P. minutaLate Oligocene, Early MioceneSmallestM2 and p1 lost
P. hyaenoidesMioceneMedium
P. dorothiaeLate Oligocene, Early MioceneLargest

de Bonis 1981 synonymized the then described Palaeogale species from Europe and North America into four taxa based on age occurrence, size difference, presence of M2, and loss of p1. Two species from Mongolia (P. ulysses and P. parvula) described by Matthew & Granger 1924 were synonymized by Simpson 1946 [11] who argued that the smaller individuals most likely were female and the larger male members of the same species, like in modern mustelids. [4]

Flynn & Galiano 1982 created the infraorder Aeluroida to accommodate Palaeogale, Ictidopappus , and Feloidea and argued that these taxa share some derived dental features not present in other feliforms, and retain some primitive dental features that have been modified in other feliforms. [12] Flynn & Galiano, however, placed Ictidopappus as incertae sedis within this infraorder, [13] and pointed out that the grouping of Palaeogale and the Viverravidae in the superfamily Viverravoidea was a hypothetical arrangement. [14]

Baskin 1998 accepted Palaeogale as closely related to the family Viverravidae but, because it does not share any "unambiguous synapomorphies with either Feliformia or Caniformia", should be considered incertae sedis within Carnivora (together with Stenogale , another very small carnivoran.) [5]

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<span class="mw-page-title-main">Carnivora</span> Order of mammals

Carnivora is an order of placental mammals that have specialized in primarily eating flesh, whose members are formally referred to as carnivorans. The order Carnivora is the fifth largest order of mammals, comprising at least 279 species.

<span class="mw-page-title-main">Amphicyonidae</span> Extinct family of carnivores

Amphicyonidae is an extinct family of terrestrial carnivorans belonging to the suborder Caniformia. They first appeared in North America in the middle Eocene, spread to Europe by the late Eocene, and further spread to Asia and Africa by the early Miocene. They had largely disappeared worldwide by the late Miocene, with the latest recorded species at the end of the Miocene in Africa. They were among the first carnivorans to evolve large body size. Amphicyonids are colloquially referred to as "bear-dogs".

<span class="mw-page-title-main">Caniformia</span> Suborder of mammals

Caniformia is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs, bears, raccoons, and mustelids. The Pinnipedia are also assigned to this group. The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia, the center of diversification of which was in Africa and southern Asia.

<span class="mw-page-title-main">Nimravidae</span> Extinct family of mammals in the order Carnivora

Nimravidae is an extinct family of carnivorans, sometimes known as false saber-toothed cats, whose fossils are found in North America and Eurasia. Not considered to belong to the true cats, the nimravids are generally considered closely related and classified as a distinct family in the suborder Feliformia. Fossils have been dated from the Middle Eocene through the Late Miocene epochs, spanning about 33.2 million years.

<span class="mw-page-title-main">Ailuridae</span> Family of carnivores

Ailuridae is a family in the mammal order Carnivora. The family consists of the red panda and its extinct relatives.

<span class="mw-page-title-main">Viverravidae</span> Extinct family of carnivorous mammals

Viverravidae is an extinct monophyletic family of mammals from extinct superfamily Viverravoidea within the clade Carnivoramorpha, that lived from the early Palaeocene to the late Eocene in North America, Europe and Asia. They were once thought to be the earliest carnivorans and ancestral to extant ones, but now are placed outside the order Carnivora based on cranial morphology as relatives to extant carnivorans.

<span class="mw-page-title-main">Eupleridae</span> Family of carnivores

Eupleridae is a family of carnivorans endemic to Madagascar and comprising 10 known living species in seven genera, commonly known as euplerids, Malagasy mongooses or Malagasy carnivorans. The best known species is the fossa, in the subfamily Euplerinae. All species of Euplerinae were formerly classified as viverrids, while all species in the subfamily Galidiinae were classified as herpestids.

<i>Phlaocyon</i> Extinct genus of carnivores

Phlaocyon is an extinct genus of the Borophaginae subfamily of canids native to North America. It lives from the Early Oligocene to the Early Miocene epoch 33.3–16.3 Mya, existing for approximately 17.3 million years. It is closely related to Cynarctoides.

<span class="mw-page-title-main">John Day Formation</span>

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References

Notes

  1. "Palaeogale". Fossilworks. Retrieved 17 December 2021.
  2. Baskin & Tedford 2005 , p. 496
  3. 1 2 Morlo & Nagel 2007 , p. 228
  4. 1 2 3 Hayes 2000 , pp. 23–26
  5. 1 2 3 Baskin 1998 , p. 165
  6. Nagel & Morlo 2003 , p. 424; Morlo & Nagel 2007 , p. 227, Fig. 2
  7. Schlosser 1888 , p. 157
  8. Simpson 1946 , p. 2
  9. 1 2 Simpson 1946 , p. 4
  10. Matthew 1902 , pp. 137–138
  11. Simpson 1946 , pp. 9–11
  12. Flynn & Galiano 1982 , p. 35
  13. Flynn & Galiano 1982 , p. 60
  14. Flynn & Galiano 1982 , p. 47

Sources

Commons-logo.svg Media related to Palaeogale at Wikimedia Commons