Mececyon trinilensis, the Trinil dog, is an extinct canid species that lived on the island of Java in Indonesia during the Pleistocene.[1]

Mececyon
Temporal range: Pleistocene
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Canidae
Genus: Mececyon
Species:
M. trinilensis
Binomial name
Mececyon trinilensis
Stremme, 1911

Description edit

The body size of Mececyon trinilensis been estimated at around 6.8–17.1 kilograms (15–38 lb),[2] comparable to a dhole.[3] This small size is the result of insular dwarfism.[2]

Habitat and ecology edit

Mececyon trinilensis is endemic to the island of Java. It was part of the Pleistocene Trinil Fauna of Java, which dates to the late Early-Middle Pleistocene.[2] Other animals of this Faunal assemblage were Bos palaesondaicus, the Indian muntjak (Muntiacus muntjak), Bubalus palaeokerabau, the Dubois santeng and Stegodon trigonocephalus. Other predators of the Trinil Fauna were the Trinil tiger (Panthera tigris trinilensis) and the leopard cat (Prionailurus bengalensis).[4][5]

Mececyon is suggested to have been a hypercarnivore.[2] It has been estimated that Mececyon trinilensis hunted prey of 1 kg to 10 kg, preferably 5 kg in size. However this number could vary, because it is yet unknown if the Mececyon trinilensis hunted in packs, or if carrion left over by the Trinil tiger influenced its feeding habits.[6] Likely prey included rats and birds.[2]

Evolution edit

Mececyon trinilensis probably ultimately originated from the mainland Xenocyon, perhaps Xenocyon lycanoides, likely via the intermediate species Megacyon merriami, which is proportionally larger than mainland Xenocyon species, and known from older Early Pleistocene fossils on Java.[2] The similarly dwarfed Sardinian dhole (Cynotherium sardous) is also suggested to have evolved from Xenocyon. Its closest living relatives are the African wild dog (Lycaon pictus) and the dhole (Cuon alpinus).[7] Some authors have suggested sinking Mececyon and Megacyon into Xenocyon.[2]

During the early Middle Pleistocene, the extinct dhole species Cuon priscus arrived on Java. It has been suggested that C. priscus outcompeted M/X. trinilensis, resulting in its absence in younger deposits.[3]

References edit

  1. ^ Elias, Scott A. (2013). Encyclopedia of Quaternary Science. Amsterdam: Elsevier. p. 1000. ISBN 9780444536433.
  2. ^ a b c d e f g van der Geer, Alexandra A.E.; Lyras, George A.; Volmer, Rebekka (October 2018). "Insular dwarfism in canids on Java (Indonesia) and its implication for the environment of Homo erectus during the Early and earliest Middle Pleistocene". Palaeogeography, Palaeoclimatology, Palaeoecology. 507: 168–179. doi:10.1016/j.palaeo.2018.07.009. S2CID 134585999.
  3. ^ a b Volmer, Rebekka; van der Geer, Alexandra A.E.; Cabrera, Patricia Andrea; Wibowo, Unggul Prasetyo; Kurniawan, Iwan (September 2019). "When did Cuon reach Java? – Reinvestigation of canid fossils from Homo erectus faunas". Geobios. 55: 89–102. doi:10.1016/j.geobios.2019.06.004. S2CID 198403467.
  4. ^ Lyras, George A. (2007). "Characteristics of Pleistocene megafauna extinctions in Southeast Asia" (PDF). Palaeogeography, Palaeoclimatology, Palaeoecology. 243 (1–2): 152–173. doi:10.1016/j.palaeo.2006.07.011.
  5. ^ Christine Hertler/ Yan Rizal (2005): Excursion guide to the Pleistocene Hominid Sites in Central and East Java, Johann Wolfgang Geothe-Universität, Frankfurt am Main, Germany/ ITB, Bandung, Indonesia
  6. ^ Rebekka Volmer (2005). Ökomorphologische Rekonstruktion pleistozäner Hyaeniden (Jawa, Indonesien) (PDF) (Diplomarbeit im Fachbereich Biowissenschaft). Frankfurt am Main: Johann Wolfgang Goethe-Universität. Archived from the original (PDF) on 15 February 2018.
  7. ^ "Body size of insular carnivores: Evidence from the fossil record (PDF Download Available)". ResearchGate. Retrieved 2017-05-04.