Gastropholis

Gastropholis is derived from the ancient Greek words "gaster" (γαστήρ) which means "belly, stomach" and, "pholis" (φολῐ́ς), a "horny scale of a reptile". The common name of these lizards is Keel-bellied Lizards.[4]

Not much is known but all species of this genus are diurnal, arboreal and often secretive. They inhabit forests, woodland and thicket of coastal plains from sea level to 2000 m altitude. Usually they live high up in the trees 10 m or more above ground level and hide in holes or under loose bark. For sun-basking and feeding (insects and other arthropods, also smaller lizards) they move on branches using their prehensile tails as balancing organs.[4]

Eggs are laid in moist tree holes. Gastropholis prasina is known to produce clutches of five-ten eggs. At 26-29 °C incubation temperature the eggs hatched after 61 days.[4][5]

Gastropholis shares with the other genera of Equatorial African lacertids (EAL; Adolfus, Congolacerta, Holaspis) the consistently absent parietal foramen, the parietal scale extending to the edge of the parietal table and a single postnasal scale.[2]

The species of Gastropholis are characterized by a high ventral scale count (10-14 rows, other EAL only 6 rows transversely), keeled ventrals (smooth in all other EAL), and a long prehensile tail. Gastropholis species are the largest of the EAL clade with adult snout-vent lengths of 80–110 mm.[3] They are well adapted for climbing with their long limbs, hooked claws and long tails.[4] For a key to the species of Gastropholis see Arnold (1989).

Four species are recognized:[6]

• Gastropholis echinata (Cope, 1862)
• Gastropholis prasina (Werner, 1904) - green keel-bellied lizard
• Gastropholis tropidopholis (Boulenger, 1916)
• Gastropholis vittata (Fischer, 1886) - keelbelly ground lizard

• Arnold, E.N. (1989): "Systematics and adaptive radiation of Equatorial African lizards assigned to the genera Adolfus, Bedriagaia, Gastropholis, Holaspis and Lacerta (Reptilia: Lacertidae)". Journal of Natural History 23: 525-555.
• Ashe, J. & Ashe, S. (1999): "Some notes on Gastropholis prasina". British Herpetological Society Bulletin 66: 31-34.
• Boulenger, G.A. (1916): "Description of a new genus of the family Lacertidae from Central Africa". The Annals and Magazine of Natural History (8) 18: 112-114.
• Cope, E.D. (1862): "On Lacerta echinata and Tiliqua dura". Proceedings of the Academy of Natural Sciences of Philadelphia 1862: 189-191.
• Ferwerda, W.H. (1997): "Gastropholis prasina, een boombewonende hagedis uit Kenia". Lacerta 55 (6): 221-223.
• Fischer, J.G. (1886): "Herpetologische Notizen". Abhandlungen des Naturwissenschaftlichen Vereins in Hamburg 9: 1-19, Taf. I – II. Description of the Genus Gastropholis
• Greenbaum, E., Villanueva, C.O., Kusamba, C., Aristote, M.M. & Branch, W.R. (2011): "A molecular phylogeny of Equatorial African Lacertidae, with the description of a new genus and species from eastern Democratic Republic of the Congo". Zoological Journal of the Linnean Society 163: 913–942.
• Schmidt, K.P. (1919): "Contributions to the herpetology of the Belgian Congo based on the collection of the American Congo Expedition, 1909-1915. Part I. Turtles, crocodiles, lizards, and chameleons". Bulletin of the American Museum of Natural History 39 (2): 385–624.
• Spawls, S., Howell, K.M., Drewes, R.C. and Ashe, J. (2002): "A Field Guide to the Reptiles of East Africa". Academic Press, Elsevier Science, San Diego, San Francisco, New York, Boston, London.
• Tornier, G. (1900): "Neue Liste der Crocodilen, Schildkröten und Eidechsen Deutsch-Ost-Afrikas". Zoologische Jahrbücher. Abteilung für Systematik, Geographie und Biologie der Tiere, Jena, 13: 579-681. (Gastropholis lutzei n.sp. = G. vittata)
• Werner, F. (1904): "Beschreibung neuer Reptilien aus den Gattungen Acanthosaura, Calotes, Gastropholis und Typhlops". Zoologischer Anzeiger 27: 461-464.