Schismotherium
| Schismotherium Temporal range:
| |
|---|---|
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Pilosa |
| Superfamily: | Megatherioidea |
| Genus: | †Schismotherium Ameghino, 1887 |
| Type species | |
| Schismotherium fractum Ameghino, 1887
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| Other species | |
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Schismotherium is an extinct genus of megatherioid sloth that lived during the Santacrucian South American land mammal age of the Miocene epoch.
Description
Schismotherium can be distinguished from the closely related Pelecyodon by a number of apomorphies. The dorsal region of the frontal bone of Schismotherium has a small postorbital process, along with anteriorly concave sutures with the nasal and maxilla. Schismotherium has very strong temporal lines characterised by a deep concavity separating them, in contrast to the slight concavity found in Pelecyodon.[1]
Taxonomy
The type specimen of Schismotherium fractum was lost since its description, leading to the specimen MACN-A 6445–6470 being designated as the neotype.[2]
Palaeobiology
Schismotherium had very good sound localisation capabilities and is suggested to have had good binocular vision, which may indicate that it was an arboreal animal. Its sensory capabilities may also be indicative of it being a social animal that used high-frequency short-range vocalisations such as predator alarms to communicate with other members of its family group or herd.[3]
References
- ^ Gaudin, Timothy; Scaife, Thomas; Toledo, Nestor; De Iuliis, Gerardo (February 2024). "Cranial osteology of the basal megatherioid sloth Schismotherium (Mammalia, Xenarthra) and its taxonomic implications". Historical Biology. 36 (2): 350–368. doi:10.1080/08912963.2022.2162399. ISSN 0891-2963. Retrieved 24 December 2025 – via Taylor and Francis Online.
- ^ Racco, Augusto; Fernicola, Juan C.; Bargo, M. Susana; Vizcaíno, Sergio F.; Iuliis, Gerardo De (2 August 2017). "On the Type of Schismotherium fractum Ameghino, 1887 (Xenarthra, Folivora, Megatherioidea) from the Early Miocene Santa Cruz Formation (Santa Cruz Province, Argentina)". Ameghiniana. 55 (1): 117–125. doi:10.5710/AMGH.18.07.2017.3109. ISSN 0002-7014. Retrieved 11 October 2025 – via BioOne Digital Library.
- ^ Ernesto Blanco, R.; Jones, Washington W. (2 April 2016). "Estimation of hearing capabilities of Early Miocene sloths (Mammalia, Xenarthra, Folivora) and palaeobiological implications". Historical Biology. 28 (3): 390–397. doi:10.1080/08912963.2014.946415. ISSN 0891-2963. Retrieved 13 October 2025 – via Taylor and Francis Online.