Fossils of Beelzebufo have been recovered from strata of the Maevarano FormationinMadagascar, dating to the late Cretaceous period, it is assumed to have lived 66-70 million years ago.[4] It is considered to be closely related to Baurubatrachus from the Late Cretaceous of Brazil, with both possibly being close relatives, though not members of, the extant South American frog family Ceratophryidae.[5]
Some 100 fossil isolated partial bones have been found. Some portions of articulated skull are also known: specimen FMNH PR 2512 (which preserves most of the braincase, part of the palate, and part of the skull roof) and specimen FMNH PR 2512 (which preserves one of the posterior flanges).[6] Researchers have been able to reconstruct parts of the frog's skeleton, including nearly the entire skull.
In early studies, it is suggested that snout-vent lengths of up to 42.5 cm (16.7 in).[4] But in later studies, animals of this species estimated to have grown to at least 23.2 cm (9.1 in) (snout-vent length), which is around the size a modern African bullfrog can reach.[6] The head of Beelzebufo was very big,[6] and bones of the skull roof show a rugous external surface, indicating at least parts of the head may have borne bony scales, called scutes.
The skull sutures are open in even the largest specimens of Beelzebufo, showing that it might have grown even bigger.[6]
Beelzebufo most likely was a predator whose expansive mouth allowed it to eat relatively large prey, perhaps even juvenile dinosaurs.[7][8] Bite force measurements from a growth series of Cranwell's horned frog (Ceratophrys cranwelli), suggest that the bite force of a large Beelzebufo—skull width 15.4 cm (6.1 in)—may have been between 500 and 2,200 newtons (110 and 490 lbf).[8]
The fossils of Beelzebufo are from Madagascar, which, while still attached to India, separated from the coast of Somalia in the earliest stage of the Late Jurassic.[9]Beelzebufo resembles horned frogs (Ceratophryidae) of South America, which raised the possibility of a close biogeographic link between Madagascar and South America during the Cretaceous.[4][6] The initial description of Beelzebufo hypothesis reignited interest and research into skeletal variation among living members of the Ceratophyridae. These investigations suggest several of the similarities between Beelzebufo and horned frogs may have evolved by convergence;[10][11] a possibility certainly acknowledged in the descriptions of Beelzebufo.[6]
A study from 2018 suggested that Beelzebufo, and other extinct frogs with ceratophryid-like traits, such as Baurubatrachus, were instead part of a more ancient group of Neobatrachia, distantly related to horned frogs.[11] However, a 2022 study recovered Baurubatrachus and Beelzebufo as sister genera, with the clade formed by the two genera in turn being the sister clade to extant Ceratophyridae.[5] Thus, Beelzebufo could represent a taxon on the stem of crown group Ceratophryidae as previously suggested.[6]
^Lawver, Lawrence A.; Gahagan, Lisa M.; and Dalziel, Ian W. D.; "A tight-fit early Mesozoic Gondwana: a plate reconstruction perspective", 1999, p. 5 "Africa-Madagascar", with citations (on-line textArchived 2008-10-12 at the Wayback Machine).
