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H.-P. Schultze, T. Marss. Revisiting Lophosteus
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Comparison: Scales and sculpture elements of L. connexus are smaller, the ridges relatively
longer and with more ridgelets than in L. superbus. The posterior-most wing-like pair of
ridgelets distinguish this taxon from all other species of Lophosteus. The ridges fuse to
form a united dentine cover on some scales of L. connexus, showing similarities to some
scales of Andreolepis hedei.
Lophosteus incrementus Burrow, 1995
1995a Lophosteus incrementus nov. sp. — Burrow: 328-332; fig. 2, pl. 1, figs 1-6 + 8-9, pl. 2,
figs 1-8.
Holotype: Scale MMM C01955 (Burrow 1995a: pl. 1, fig. 6).
Additional material: see Burrow (1995a).
Type locality: Site C661, Trundle beds, central New South Wales, Australia.
Type horizon: Base of Garra Formation, Pedavis pesavis Conodont Zone, upper
Lochkovian, Lower Devonian.
Diagnosis: Short, tubercle-like ridges not running over the entire free (exposed) field,
no crest, but many ridgelets, smaller ridges in-between larger ones, small triangular
pustules on anterior overlapped field.
Description: see Burrow (1995a).
Comparison: The star-like tubercles of L. incrementus (Burrow 1995a: pls 1 and 2)
are lower, the tip of the tubercles is sharply pointed, and the bony pustules on the
anterior overlapped area are triangular and relatively larger and more strongly developed
than in L. canadensis and L. superbus.
Lophosteus ohesaarensis n. sp.
Fig. 5
1986 Lophosteus superbus — Märss: pl. 34, fig. 6
Holotype: Scale GIT 382-87 (Fig. 5 A).
Etymology: Named after locality of origin (Ohesaare cliff).
Additional material: Scales GIT 382-82, 382-88-92, 382-121, -123 and tessera GIT
382-93, from Ohesaare Cliff, Saaremaa; scale GIT 232-42 (= Pi 6218; Märss 1986: pl.
34, fig. 6) from Ventspils, Latvia.
Type locality: Ohesaare cliff, Saaremaa, Estonia.
Type horizon: Ozarkodina remscheidensis eosteinhornensis Conodont Subzone,
Ohesaare Regional Stage, upper Pridoli, Upper Silurian.
Localities: Bore holes Ventspils, depth 280,0 m and Kolka-54, depth 205.6 – 205.9 m
in Latvia, Jura Formation, upper Pridoli, Upper Silurian.
Diagnosis: Scales with fine parallel ridgelets on crest, ridgelets change angle from 10°
to nearly 90° to crest on lateral sides of the ridges; lower part of ridgelets with nodular
serrations; anterior overlapped field weakly pustulate.
Description: Lophosteus superbus is the common species at Ohesaare cliff, Saaremaa;
L. ohesaarensis is rare (10 scales and 8 pieces of bones and spines). A deep scale has
been chosen as the holotype (Fig. 5 A); two elongate, steep and two smaller intercalated