Titanichthys (meaning "titanic fish") is an extinct genus of giant, aberrant marine placoderm from shallow seas of the Late Devonian of Morocco, Eastern North America, and possibly Europe.
Phylogeny
Titanichthys is thought to have been a basal
Aspinothoracidi, closest related to
Bungartius and
Tafilalichthys.
Species
The genus shows a great diversity in the
Famennian-aged
Cleveland Shale, though species are also found in similarly aged strata in Morocco and possibly the Holy Cross Mountains in Poland.
T. agassizi
This is the type species, from the Cleveland Shale. Its infrognathals are strongly recurved medially, and is elongated with a spatula-like process at the anterior end. The headshield averages about in length.
T. attenuatus
This Cleveland Shale species is based on an infragnathal bone more than in length. May possibly be a synonym of
T. agassizi.
T. clarkii
This Cleveland Shale species has infragnathals that are not as recurved as
T. agassizi's. The cranial roof is comparatively narrower and more rounded. It is the largest known species in the genus, and possibly one of the largest Devonian vertebrates known. The head is about in length.
T. hussakofi
This Cleveland Shale species is known from a badly preserved, incomplete infragnathal. It was originally described by Claypole as "Brontichthys clarki" in 1894.
As "Brontichthys" is a junior synonym of
Titanichthys, it should not be confused with another, similarly-named arthrodire,
Bruntonichthys of
Dunkleosteidae.
T. rectus
This Cleveland Shale species has an infragnathal as large as that of
T. clarkii, though
T. rectus' infragnathal is much straighter, and does not have a spatula-like process on its anterior end.
T. kozlowskii
This species placement within the genus is in doubt. It is based on incomplete nuchal and central plates found in Upper Famennian-aged marine strata of the Holy Cross Mountains in Poland.
T. termieri
This species is found in Lower Famennian-aged marine strata of Tafilalet, Southern Morocco. The fossil material of this species strongly suggests it is as large as the Cleveland Shale'
T. clarkii.
The average combined length of the head and trunk shields for
T. termieri is estimated to be
When the first fossils of
T. termieri were found by geologist
Henri Termier, the specimens were originally placed within the genus
Gorgonichthys - that is, after Termier was able to convince his colleagues that the bone scraps were of a placoderm, and not a
dinosaur.
[See Janvier (1998) p.323 for details.]
Bibliography
-
(1998): Early Vertebrates. Oxford University Press, Oxford, New York.
Further reading
