Haramiyida

Haramiyida Temporal range: Late Triassic-Late Cretaceous, 216.5–65 Ma PreЄ Є O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Synapsida
Order:	Therapsida
Suborder:	Cynodontia
Clade:	Mammaliaformes
Clade:	†Haramiyida Hahn, Sigogneau-Russell & Wouters, 1989
Subgroups
†Haramiyoidea †Haramiyidae †Haramiya †Haramiyaviidae †Haramiyavia †Kirtlingtonia †Millsodon †Avashishta †Hahnodontidae †Theroteinida †Theroteinidae †Theroteinus †Euharamiyida †Eleutherodon †Sineleutherus †Arboroharamiya †Shenshou †Xianshou

Haramiyidans seem to be the earliest known herbivores amongst basal mammals. Their teeth, which are by far the most common remains, resemble those of the multituberculates. However, based on Haramiyavia, the jaw is less derived; and at the level of evolution of earlier basal mammals like Morganucodon and Kuehneotherium, with a groove for ear ossicles on the dentary. They are the longest lived mammalian clade of all time. However, a more recent study, in November 2015, may dispute this and suggested the Haramiyida were not mammals after all, but were part of a more ancestral side branch instead.

Relationships

Haramiyids show certain similarities to multituberculates, a group of mammals that survived until about 40 million years ago. So it's possible that haramiyids are ancestral to multituberculates, although the available evidence is insufficient to be conclusive. Certain characteristics of the teeth seem to rule out a special relationship between the two groups, although some scientists still unite haramiyids (or at least euharamiyids) and multituberculates in the Allotheria hypothesis.

Taxonomy

For a long time it was unknown if haramiyids were crown-group mammals, or if they should be placed in the stem-group Mammaliaformes. This uncertainty stems from the fact that haramiyid remains were mostly restricted to teeth and jaw fragments. However, new discoveries of much more complete haramiyid fossils have settled the issue—haramiyids are undoubtedly crown-group mammals. For example, the specimens show evidence of a typical mammalian middle ear, the area just inside the eardrum that turns vibrations in the air into ripples in the ear's fluids. The middle ears of mammals are unique in that they have three bones, as evidenced in the new fossils.

Order †Haramiyida Hahn, Sigogneau-Russell & Wouters 1989 [Haramiyoidea Hahn 1973 sensu McKenna & Bell 1997]

• †Kirtlingtonia catenata Butler & Hooker 2005 [tooth-taxa]
• †Millsoson superstes Butler & Hooker 2005 [tooth-taxa]
• Family †Haramiyaviidae Butler 2000
  • †Haramiyavia clemmenseni Jenkins et al. 1997
• Family †Eleutherodontidae Kermack et al. 1998 [Arboroharamiyidae Zheng et al. 2013; Euharamiyida Bi et al. 2014; Eleutherodontida Kermack et al. 1998]
  • †Megaconus mammaliaformis Zhou et al. 2013
  • †Shenshou lui Bi et al. 2014
  • †Arboroharamiya jenkinsi Zheng et al. 2013
  • †Eleutherodon oxfordensis Kermack et al. 1998
  • †Xianshou Bi et al. 2014
    • †X. linglong Bi et al. 2014
    • †X. songae Bi et al. 2014
  • †Sineleutherus Martin, Averianov & Pfretzschner 2010
    • †S. uyguricus Martin, Averianov & Pfretzschner 2010
    • †S. issedonicus Averianov, Lopatin & Krasnolutskii 2011
• Family †Theroteinidae Sigogneau-Russell, Frank & Hammerle 1986
  • †Theroteinus nikolai Sigogneau-Russell, Frank & Hammerle 1986
• Family †Thomasiidae Poche 1908 [Haramiyidae Simpson 1947 sensu Jenkins et al. 1997; Microlestidae Murry 1866; Microcleptidae Simpson 1928]
  • †Eoraetica
  • †Avashishta bacharamensis Anantharaman & al. 2006
  • †Allostaffia aenigmatica (Heinrich 1999) Heinrich 2004 [Staffia Heinrich 1999 non Schubert 1911; Staffia aenigmatica Heinrich 1999]
  • †Thomasia Poche 1908 [Haramiya Simpson 1947; Hypnoprymnopsis Dawkins 1864; Microlestes Plieninger 1847 non Schmidt Goebel 1846; Microcleptes Simpson 1928 non Newman 1840; Plieningeria Krausse 1919; Stathmodon Henning 1911]
    • †T. rhaeticus (Dawkins 1864) [Hypsiprymnopsis rhaetica Dawkins 1864; Haramiya rhaeticus (Dawkins 1864); Microlestes rhaeticus (Dawkins 1864)]
    • †T. woutersi Butler & MacIntyre 1994
    • †T. hahni Butler & MacIntyre 1994
    • †T. moorei (Owen 1871) Butler & MacIntyre 1994 [Haramiya moorei (Owen 1871) Simpson 1947; Microleptes moorei Owen 1871; Microlestes (Plagiaulax) moorei Henning 1922; Haramyia moorei Piveteau 1961 (sic); Microleptes mosrei Piveteau 1961 (sic); Microcleptes moorei] [upper tooth]
    • †T. antiqua (Plieninger 1847) Poche 1908 [Microlestes antiquus Plieninger 1847; Haramiya antiqua (Plieninger 1847); Microleptes fissurae Simpson 1928; Haramiya fissurae (Simpson 1928); Haramiya butleri Sigogneau-Russell 1990; Thomasia anglica Simpson 1928] [lower tooth]

Lifestyle

Haramiyids seem to have generally been herbivorous or omnivorous, possibly the first mammalian herbivores. At least some species were very good climbers and were similar to modern day squirrels; and several others have more recently been more recently reassessed as possibly arboreal. In fact, general arboreal habits might actually explain their rarity in the fossil reccord.

Range

Most fossils have been reported from Europe, but some are known from Africa and Greenland. Since 2005, the published range extended to Mongolia and China. The age of haramiyid fossils range from Upper Triassic up to Late Cretaceous. This has important implications: the fact that haramiyids were present in the Late Triassic supports the idea that crown-group mammals originated at least 208 million years ago, much earlier than some previous research suggests.

The youngest haramiyid fossil genus is Avashishta bacharamensis from the Maastrichtian of India. Cretaceous haramiyids are previously known from the Early Cretaceous of Morocco, suggesting that these animals may have survived in gondwannan landmasses as relics. With a temporal range of at least 150 million years, they are the longest lived mammalian lineage.

External links

• Palaeos, Mammaliaformes: Allotheria
• John H Burkitt, Mammals, A World Listing of Living and Extinct Species. Archived from the original on 21 December 2004. Retrieved 2015-06-18.
• Mikko K Haaramo, Haramiyida

References

• Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo, Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure (New York: Columbia University Press, 2004), 249-260.