Most ichthyodectiforms ranged between 1 and 5 meters (3–15 ft) in length. Most of known
taxa were
predators, feeding on smaller fish; in several cases, larger ichthyodectiforms preyed on smaller members of the order. Some
species had remarkably large teeth, though others, such as Gillicus arcuatus, had small ones and sucked in their prey. Heckelichthys preopercularis is a rare example of non-predatory ichthyodectiform, more likely to be microphagous, fed on small particles.[3] There is evidence that at least one species, Xiphactinus audax, may have been
endothermic ("warm-blooded").[4]
Systematics
The
basal phylogeny is badly resolved, leading to many ichthyodectiforms that are simply known to be rather primitive, but where nothing certain can be said about their precise relationships.
^Cavin, L.; Berrell, R. W. (2019). "Revision of Dugaldia emmilta (Teleostei, Ichthyodectiformes) from the Toolebuc Formation, Albian of Australia, with comments on the jaw mechanics". Journal of Vertebrate Paleontology. 39 (1): e1576049.
Bibcode:
2019JVPal..39E6049C.
doi:
10.1080/02724634.2019.1576049.
S2CID190880286.
^
abHacker, R. J.; Shimada, K. (2021). "A new ichthyodectiform fish (Actinopterygii: Teleostei) from the Arlington Member (mid-Cenomanian) of the Upper Cretaceous Woodbine Formation in Texas, USA". Cretaceous Research. 123: 104798.
Bibcode:
2021CrRes.12304798H.
doi:
10.1016/j.cretres.2021.104798.
S2CID233806833.
^Kim, H.; Chang, M.; Wu, F.; Kim, Y. (2014). "A new ichthyodectiform (Pisces, Teleostei) from the Lower Cretaceous of South Korea and its paleobiogeographic implication". Cretaceous Research. 47: 117–130.
Bibcode:
2014CrRes..47..117K.
doi:
10.1016/j.cretres.2013.11.007.
^Kaddumi, Hani F. (2009). "Ichthyodectids of the late Maastrichtian sediments of the Muwaqqar Chalk Marl Formation of Harrana". Fossils of the Harrana Fauna and the Adjacent Areas. Amman: Eternal River Museum of Natural History.
OCLC709582892.
^Cope, E. D. (1870). On the Saurodontidæ. Proceedings of the American Philosophical Society 11:529-538
^Cope, E. D. (1873). On two new species of Saurodontidae. Proceedings of the Academy of Natural Sciences of Philadelphia 25:2-339
^Vullo, R., Buffetaut, E. and Everhart, M.J. (2012). "Reappraisal of Gwawinapterus beardi from the Late Cretaceous of Canada: a saurodontid fish, not a pterosaur." Journal of Vertebrate Paleontology, 32(5): 1198-1201.
doi:
10.1080/02724634.2012.681078
Most ichthyodectiforms ranged between 1 and 5 meters (3–15 ft) in length. Most of known
taxa were
predators, feeding on smaller fish; in several cases, larger ichthyodectiforms preyed on smaller members of the order. Some
species had remarkably large teeth, though others, such as Gillicus arcuatus, had small ones and sucked in their prey. Heckelichthys preopercularis is a rare example of non-predatory ichthyodectiform, more likely to be microphagous, fed on small particles.[3] There is evidence that at least one species, Xiphactinus audax, may have been
endothermic ("warm-blooded").[4]
Systematics
The
basal phylogeny is badly resolved, leading to many ichthyodectiforms that are simply known to be rather primitive, but where nothing certain can be said about their precise relationships.
^Cavin, L.; Berrell, R. W. (2019). "Revision of Dugaldia emmilta (Teleostei, Ichthyodectiformes) from the Toolebuc Formation, Albian of Australia, with comments on the jaw mechanics". Journal of Vertebrate Paleontology. 39 (1): e1576049.
Bibcode:
2019JVPal..39E6049C.
doi:
10.1080/02724634.2019.1576049.
S2CID190880286.
^
abHacker, R. J.; Shimada, K. (2021). "A new ichthyodectiform fish (Actinopterygii: Teleostei) from the Arlington Member (mid-Cenomanian) of the Upper Cretaceous Woodbine Formation in Texas, USA". Cretaceous Research. 123: 104798.
Bibcode:
2021CrRes.12304798H.
doi:
10.1016/j.cretres.2021.104798.
S2CID233806833.
^Kim, H.; Chang, M.; Wu, F.; Kim, Y. (2014). "A new ichthyodectiform (Pisces, Teleostei) from the Lower Cretaceous of South Korea and its paleobiogeographic implication". Cretaceous Research. 47: 117–130.
Bibcode:
2014CrRes..47..117K.
doi:
10.1016/j.cretres.2013.11.007.
^Kaddumi, Hani F. (2009). "Ichthyodectids of the late Maastrichtian sediments of the Muwaqqar Chalk Marl Formation of Harrana". Fossils of the Harrana Fauna and the Adjacent Areas. Amman: Eternal River Museum of Natural History.
OCLC709582892.
^Cope, E. D. (1870). On the Saurodontidæ. Proceedings of the American Philosophical Society 11:529-538
^Cope, E. D. (1873). On two new species of Saurodontidae. Proceedings of the Academy of Natural Sciences of Philadelphia 25:2-339
^Vullo, R., Buffetaut, E. and Everhart, M.J. (2012). "Reappraisal of Gwawinapterus beardi from the Late Cretaceous of Canada: a saurodontid fish, not a pterosaur." Journal of Vertebrate Paleontology, 32(5): 1198-1201.
doi:
10.1080/02724634.2012.681078