| Kongonaphon Temporal range: Mid to Late Triassic,
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| Life restoration | |
Scientific classification 
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| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Ornithodira |
| Clade: | †Pterosauromorpha |
| Family: | †Lagerpetidae |
| Genus: | †Kongonaphon Kammerer et al., 2020 |
| Type species | |
| †Kongonaphon kely Kammerer et al., 2020
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Kongonaphon is an extinct genus of lagerpetid avemetatarsalians from the Middle to Late Triassic of Madagascar. It contains a single species, Kongonaphon kely, which is known from a fragmentary partial skeleton. This fossil hails from the late Ladinian or early Carnian-age "basal Isalo II beds". As the first lagerpetid found in Africa, Kongonaphon extends the range of the family significantly. It possessed a combination of features from various other lagerpetids, but developed particularly long and slender leg bones. Kongonaphon is also the first lagerpetid for which fossils of the snout and teeth are known. It was likely an insectivore based on the shape and texture of its teeth.[1]
Kongonaphon is notable for its minuscule size, even compared to other small early avemetatarsalians. The proportionally elongated femur was only about 4 cm (1.6 inches) long, and the total height of the animal was estimated at around 10 cm (3.9 inches). Alongside other miniaturized archosaurs such as Scleromochlus, it suggests that avemetatarsalians experienced an abrupt reduction in size early in their evolution. This may explain the poor preservation and scarcity of early and middle Triassic avemetatarsalian fossils. A small size also may have helped them exploit a variety of new ecological niches. The most successful avemetatarsalian subgroups, pterosaurs and dinosaurs, may have evolved as a result of this abrupt size reduction. Miniaturization has been correlated with the evolution of flight (a defining feature of pterosaurs) and the acquisition of bipedalism (which was utilized by many dinosaurs). It would also lead to poor heat retention, encouraging the evolution of feathers or other filamentous structures.
Although Kongonaphon is clearly an ornithodiran, there is uncertainty whether it was closer to pterosaurs or dinosaurs. When placed in a phylogenetic analysis without Scleromochlus, lagerpetids are found to be basal dinosauromorphs (closer to dinosaurs). However, the inclusion of Scleromochlus leads to the analysis tentatively supporting lagerpetids as pterosauromorphs (closer to pterosaurs).[1] Fossil remains from other lagerpetids described in late 2020 strongly support the hypothesis that lagerpetids were pterosauromorphs.[2][3]
- ^ a b Kammerer, Christian F.; Nesbitt, Sterling J.; Flynn, John J.; Ranivoharimanana, Lovasoa; Wyss, André R. (2020-07-02). "A tiny ornithodiran archosaur from the Triassic of Madagascar and the role of miniaturization in dinosaur and pterosaur ancestry". Proceedings of the National Academy of Sciences. 117 (30): 17932–17936. doi:10.1073/pnas.1916631117. ISSN 0027-8424. PMC 7395432. PMID 32631980.
- ^ Ezcurra, Martín D.; Nesbitt, Sterling J.; Bronzati, Mario; Dalla Vecchia, Fabio Marco; Agnolin, Federico L.; Benson, Roger B. J.; Brissón Egli, Federico; Cabreira, Sergio F.; Evers, Serjoscha W.; Gentil, Adriel R.; et al. (2020-12-09). "Enigmatic dinosaur precursors bridge the gap to the origin of Pterosauria". Nature. 588 (7838): 445–449. doi:10.1038/s41586-020-3011-4. ISSN 0028-0836. PMID 33299179. S2CID 228077525.
- ^ Baron, Matthew G. (2021-08-20). "The origin of Pterosaurs". Earth-Science Reviews. 221: 103777. doi:10.1016/j.earscirev.2021.103777. ISSN 0012-8252.