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68 ADVANCES IN PALAEOICHTHYOLOGY
ridges cover the scale, the ridgelets run nearly parallel on the crest, barely reaching the
posterior end of the crest. The angle of the ridgelets on the lateral sides changes from
10° to nearly vertical to the crest posteriad on the lateral sides. The lower part of each of
the ridgelets bears a nodular serration increasing in number with the size of the tubercles
(Fig. 5 C). One tessera with a vertical tubercle (Fig. 5 B) is assigned to the species,
because it shows fine ridgelets running to the tip in addition to stronger ridgelets with
nodules located more basally. The ridges on the spines have parallel ridgelets on their
anterior part.
Comparison: L. uralensis is closest to L. ohesaarensis; the ridgelets do not form
chevrons in L. ohesaarensis in contrast to L. uralensis and L. canadensis. L. superbus
has broader ridges with strong ridgelets that form a distinct angle to the crest. The
serration of the lower part of the ridgelets is unique to L. ohesaarensis.
Lophosteus sp. indet.
2000 Lophosteus? sp. — Turner et al.: 492; fig. 3 F.
Material: A section of a single spine QMF35785 (Turner et al. 2000: fig. 3 F).
Locality: Between Gray Creek and Basalt Bore, Broken River district, north Queensland,
Australia.
Horizon: Pedavis pesavis - Eognathodus sulcatus conodont zones, Shield Creek
Formation, upper Lochkovian/lower Pragian, Lower Devonian.
Description: Turner et al. (2000) cited the specimen in connection with the description
of microvertebrates from the Broken River district, Queensland. A short piece of one
spine is preserved. It shows five arch-like tubercles with a smooth crest and with ridgelets
on the sides; smaller pointed tubercles are present on the side of the spine.
Lophosteus uralensis n. sp.
Fig. 6
1997 Actinopterygii gen. et sp. A — Märss: pl. 5, figs 14-16.
1997 Osteichthyan — Märss: 35.
Holotype: scale GIT 297-62 (= Pi 7236; Märss 1997: pl. 5, fig. 15).
Etymology: Named after region of origin (Ural).
Additional material from the type locality: 2 scales (GIT 297-63 + 297-61 [= Pi 7237
+ 7238; Märss 1997: pl. 5, figs 16 + 14])
Type locality: locality 67, Kuba River, Ufa amphitheatre, western slope of Central
Ural.
Type horizon: lower Lochkovian, Lower Devonian.
Diagnosis: Ridgelets of ridges reach to top of the crest where they join and form
chevrons; oblique angle between crest and ridgelets (around 10°); anterior overlapped
field pustulate.
Description: Scales of the new species are only known from the Central Ural. They
show the main features of Lophosteus, pustulate anterior overlapped field, separated
ridges of different size on the free field and a narrow dorsal overlapped area without a