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70 ADVANCES IN PALAEOICHTHYOLOGY
Fig. 6. Lophosteus uralensis n. sp.; lower Lochkovian, Lower Devonian; Kuba River, Ufa
amphitheatre, western slope of Central Ural.
A, scale of right flank, holotype GIT 297-62; B, C, details of A. SEM pictures, scale bars
equal 100 µm.
chevrons in the lower ridges; the ridgelets are separated by a distinct crest in the most
prominent ridge. The angle between the crest and the ridgelets is around 10°. The pores
between the ridges open in a meshwork of bone (Fig. 6 C) in contrast to the smooth
bony surface evident in scales of other species. A second scale shows the same features,
but the anterior pustulate area is more distinct; small pustules form rows parallel to the
anterior margin of the scale, and more posteriorly they partially join with each other.
The plate surface is also uneven posteriorly. Vascular canal pores are very small and
hidden between the fine pustules of the basal plate.
Comparison: The species is distinguished from L. canadensis by the length of the
ridges, the formation of a crest in adult ridges, ridgelets that form chevrons and welldeveloped,
partially joined fine pustules on the anterior overlapped area.
Non Lophosteus
1995 lophosteiform or actinopterygian scale – Turner et al.: fig. 2.3 + 2.6.
Material: one scale (IGB B48-y2.1; Turner et al. 1995: fig. 2.3) and one spine (IGB
53-y1.4; Turner et al. 1995: fig. 2.3).
Locality: Longmenshan section, southern China.
Horizon: Ganxi and Xiejiawan formations, Emsian, Lower Devonian.
Description: The figured scale is that of the actinopterygian Ligulalepis.