Early Cretaceous Freshwater Fish Fauna in Kyushu, Japan

Early Cretaceous Freshwater Fish Fauna in Kyushu, Japan 171
U2
U1p
Fig. 47. Aokiichthys uyenoi gen. et sp. nov., caudal region of the holotype, KMNH VP
100,176.
articular is not visible and the posterior part of lower jaw is poor in preservation.
The premaxilla bears small canine like teeth. The teeth of jaws are almost same in
size. The posterior end of the lower jaw is placed below the posterior margin of the
orbit. There are villiform teeth on the endopterygoid. The frontal is long and
wide, and carries a superficial canal. The canal is separated at the posterior end.
A part of the opercle is visible (Fig. 46).
The total number of vertebrae is 34, with 18 caudal vertebrae. The number of
ribs is 14. There is a series of median supraneurals beginning immediately behind
the head and ending above the first caudal vertebra. The first preural centrum
bears the narrow parhypural. The neural arch and spine of the first preural
centrum are complete. There are 7 hypurals. The first hypural is the largest.
The second hypural is about one third of the first one in width. There is a space
between the second and third hypurals. The third to seventh hypurals are slender.
There are two ural centra. The anterior and posterior parts of the first ural centrum
are present. The second ural centrum bears at least five hypurals (HYU3-7).
Three uroneurals are visible. The first uroneural extends forward to the first ural
centrum. The anterior ends of the uroneurals are not visible. The epural is not
visible (Fig. 47).
Description of the paratypes.
In KMNH VP 100,177, the body depth is contained 2.5 times in the standard