Laomaki Temporal range: Early Oligocene ~ | |
---|---|
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Mammalia |
Order: | Primates |
Suborder: | Strepsirrhini |
Family: | † Sivaladapidae |
Genus: | † Laomaki Ni et al. 2016 |
Type species | |
†Laomaki yunnanensis Ni et al., 2016 |
Laomaki is a genus of adapiform primate that lived during the Early Oligocene in Asia, containing only the species Laomaki yunnanensis. It was described from a right maxilla fragment. Its molars and premolars are somewhat similar to those of Rencunius and Anthradapis respectively. Its placement within the family Sivaladapidae is uncertain; it has not been placed in a subfamily. It has been found at sites in Jammu and Kashmir and Yunnan, having lived around the time of the Eocene–Oligocene transition.
The type species of Laomaki, L. yunnanensis, was first described by Xijun Ni, Qiang Li, Lüzhou Li, and K. Christopher Beard in 2016 from a right maxilla fragment found at the Early Oligocene Lijiawa fossil site, part of the Caijiachong Formation in Yunnan Province, China. The generic name comes from the Mandarin word lao (lit. 'old') and the Malagasy word maky (lit. 'lemur'), while the specific name is in reference to the geographic location of the remains. [1] As of 2023, no additional species of Laomaki have been described. [2]
Laomaki belongs to the family Sivaladapidae, a group of adapoid primates whose relationship with other taxonomic groups remains uncertain; they are possibly close relatives of the European cercamoniids. The placement of Laomaki within the family is unknown, making the genus incertae sedis . A 2017 phylogenetic study found support for a clade within Sivaladapidae containing the basal genera Laomaki, Hoanghonius , Paukkaungia , and Kyitchaungia . While the original description of Laomaki found it to be intermediate between the genera Hoanghonius and Rencunius , the aforementioned 2017 study found Laomaki closer to Hoanghonius, as sister taxa. [3]
Unlike any other sivaladapid besides Rencunius, Laomaki has strongly developed conules on its upper molars. Both the upper and lower molars of Laomaki differ from those of the former taxon in their extremely crenulated enamel, pyramidal cusps, and sharper crests. The upper molars are also more transverse than those of Rencunius, with pyramidal conules as opposed to bulbous ones, and its hypocones (small cusps found on mammalian upper molars) are smaller. The P4 and P4 premolars being are less molarized than those of Yunnanadapis and Miocene sivaladapids. [1] Its premolars were also compared to those of Anthradapis in the latter's taxonomic description. [4] It has an estimated body mass of 188 grams (6.6 oz). [3]
The holotype of the genus Laomaki was found in strata of Early Oligocene age in Yunnan, about 34 million years old. This coincides with the Eocene-Oligocene transition, an episode of cooler and drier climactic conditions that led to the extirpation of primates in North America and Europe. Still, several clades of primates managed to persist in Asia, Sivaladapidae among them. In China, Myanmar, and Thailand, anthropoids dominate the Late Eocene primate fossil record; by contrast, only one of six primates known from the Early Oligocene in Yunnan is a member of the group, while multiple sivaladapid genera, including Laomaki, have been discovered. [1] Specimens have also been found in the Lower Siwalik deposits near the town of Ramnagar in Jammu and Kashmir, with a mean age estimate of c. 33 million years. [3]
Within China, Laomaki is known solely from the Ulantatalian stage (a Chinese land mammal age for fossils of Early Oligocene age named after the Ulantatal area in Inner Mongolia). Other mammalian taxa known exclusively from this stage include the artiodactyls Eumeryx culminis and Praetragulus gobiae ; the lagomorphs Desmatolagus pusillus , D. youngi , and Ordolagus teilhardi ; the hyaenodont Hyaenodon neimongoliensis ; the erinaceomorph Palaeoscaptor acridens ; the other primates Yunnanadapis folivorus , Y. imperator , Gatanthropus micros , Bahinia banyueae , and Oligotarsius rarus ; and over twenty species of rodents belonging to various genera. [5] Early Oligocene mammal taxa recovered specifically from the Lijiawa fossil site include Ptilocercus kylin (a treeshrew), Gigantamynodon giganteus , Cricetops, and Eucricetodon. [6]
During the Eocene-Oligocene transition, the physical environment of Asia changed significantly as a result of aridification, with open grasslands replacing forests, although a 2020 study found that this change in climate may have had a less dramatic effect on fauna than previously thought. [5] On a geographic scale, the Paratethys Sea retreated from Central Asia, the uplift of the Himalayas continued, and the South China Sea opened. [1]
The treeshrews are small mammals native to the tropical forests of South and Southeast Asia. They make up the entire order Scandentia, which split into two families: the Tupaiidae, and the Ptilocercidae.
The simians, anthropoids, or higher primates are an infraorder of primates containing all animals traditionally called monkeys and apes. More precisely, they consist of the parvorders Platyrrhini and Catarrhini, the latter of which consists of the family Cercopithecidae and the superfamily Hominoidea.
Oligopithecus is a fossil primate that lived in Africa during the Early Oligocene. It is represented by one species, Oligopithecus savagei, known from one jaw bone found in Egypt.
Ptilocercus is a genus of treeshrew and the sole member of the family Ptilocercidae.
Bugtilemur is an extinct genus of Strepsirhine primate belonging to the adapiform family Ekgmowechashalidae.It is represented by only one species, B. mathesoni, which was found in the Chitarwata Formation of Pakistan.
Tupaiidae is one of two families of treeshrews, the other family being Ptilocercidae. The family contains three living genera and 19 living species. The family name derives from tupai, the Malay word for treeshrew and also for squirrel which tupaiids superficially resemble. The former genus Urogale was disbanded in 2011 when the Mindanao treeshrew was moved to Tupaia based on a molecular phylogeny.
Ekgmowechashala is an extinct genus of primate belonging to Adapiformes.
Dermotherium is a genus of fossil mammals closely related to the living colugos, a small group of gliding mammals from Southeast Asia. Two species are recognized: D. major from the Late Eocene of Thailand, based on a single fragment of the lower jaw, and D. chimaera from the Late Oligocene of Thailand, known from three fragments of the lower jaw and two isolated upper molars. In addition, a single isolated upper molar from the Early Oligocene of Pakistan has been tentatively assigned to D. chimaera. All sites where fossils of Dermotherium have been found were probably forested environments and the fossil species were probably forest dwellers like living colugos, but whether they had the gliding adaptations of the living species is unknown.
Azibiidae is an extinct family of fossil primate from the late early or early middle Eocene from the Glib Zegdou Formation in the Gour Lazib area of Algeria. They are thought to be related to the living toothcombed primates, the lemurs and lorisoids, although paleoanthropologists such as Marc Godinot have argued that they may be early simians. It includes the genera Azibius and Algeripithecus, the latter of which was originally considered the oldest known simian, not a strepsirrhine.
Afrasia djijidae is a fossil primate that lived in Myanmar approximately 37 million years ago, during the late middle Eocene. The only species in the genus Afrasia, it was a small primate, estimated to weigh around 100 grams (3.5 oz). Despite the significant geographic distance between them, Afrasia is thought to be closely related to Afrotarsius, an enigmatic fossil found in Libya and Egypt that dates to 38–39 million years ago. If this relationship is correct, it suggests that early simians dispersed from Asia to Africa during the middle Eocene and would add further support to the hypothesis that the first simians evolved in Asia, not Africa. Neither Afrasia nor Afrotarsius, which together form the family Afrotarsiidae, is considered ancestral to living simians, but they are part of a side branch or stem group known as eosimiiforms. Because they did not give rise to the stem simians that are known from the same deposits in Africa, early Asian simians are thought to have dispersed from Asia to Africa more than once prior to the late middle Eocene. Such dispersals from Asia to Africa also were seen around the same time in other mammalian groups, including hystricognathous rodents and anthracotheres.
Indraloris is a fossil primate from the Miocene of India and Pakistan in the family Sivaladapidae. Two species are now recognized: I. himalayensis from Haritalyangar, India and I. kamlialensis from the Pothohar Plateau, Pakistan. Other material from the Potwar Plateau may represent an additional, unnamed species. Body mass estimates range from about 2 kg (4.4 lb) for the smaller I. kamlialensis to over 4 kg (8.8 lb) for the larger I. himalayensis.
Sivaladapidae is an extinct family of adapiform primates from Asia. They survived longer than any other adapiform primate because they were able to shift south as the climate cooled. Their remains date from the Eocene through the Miocene.
Urtinotherium is an extinct genus of paracerathere mammals. It was a large animal that was closely related to Paraceratherium, and found in rocks dating from the Late Eocene to Early Oligocene period. The remains were first discovered in the Urtyn Obo region in Inner Mongolia, which the name Urtinotherium is based upon. Other referred specimens are from northern China.
Sivaladapis is a genus of adapiform primate that lived in Asia during the middle Miocene.
Siamoperadectes is a genus of non-marsupial metatherian from the Miocene of Thailand. A member of Peradectidae, it is the first member of its clade known from South Asia, and among the last non-marsupial metatherians.
Helohyidae were a group of artiodactyl mammals. They were most prominent in the mid-to-upper Eocene.
Achaenodon is an extinct artiodactyl mammal, possibly belonging to the family Helohyidae. It lived in the mid-late Eocene and its fossil remains have been found in North America.
Kapi is an extinct primate genus that lived in northern India about 13.8 to 12.5 million years ago during the Miocene. The only species, K. ramnagarensis, was described in 2020 and is known from a complete lower molar. The fossil was discovered in 2015 from Ramnagar, a town in Jammu and Kashmir, for which the species name was created. Though originally identified as member of the gibbons and popularised in the news as the oldest gibbon, it was later reassessed as a pliopithecoid, a group of extinct Old World monkeys.
Ramadapis sahnii was a primitive primate belonging to Sivaladapidae that existed around 11 to 14 million years ago. Only a mandible was found at the dig site, which was near Ramnagar in Udhampur district in Jammu and Kashmir specifically the lower Siwalik deposits. The jawbone indicates that Ramadapis resembled a modern day ring-tailed lemur. The early lemur was named after Ashok Sahni, who discovered the first sivaladapid in the Siwalik deposits. The mandible was only around one and a quarter inch long, which led scientists to assume that it was only around 11 pounds.
Palaeohodites is an extinct genus of primate from the Eocene Nadu Formation of China. Living about 35 million years ago during the late Eocene, Palaeohodites belongs to an extinct group of primates known as adapiforms, related to modern day lemurs and lorises. Specifically, this genus is one member of the family Ekgmowechashalidae, known primarily from the Eocene and Oligocene of Asia. Notably, Palaeohodites has been recovered as the sister taxon of Ekgmowechashala, the latest primate known to exist in North America before the arrival of humans at the end of the Pleistocene.