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66 ADVANCES IN PALAEOICHTHYOLOGY
Lophosteus connexus Märss, 1986
Fig. 4
1986 Lophosteus? connexus n. sp. — Märss: 59, 90; pl. 34, figs 7-11.
1997 Lophosteus? connexus — Märss: 35; fig. 8.
2000 Lophosteus? connexus — Märss: 68.
Holotype: scale GIT 232-413 (= Pi 7042; Märss 1986: pl. 34, fig. 10).
Additional material: 15 scales and plates.
Type locality: Vaivere outcrop, Saaremaa, Estonia.
Type horizon: lowermost part of Äigu Beds, Ozarkodina remscheidensis
eosteinhornensis Conodont Subzone (Viira and Männik 1997), Kaugatuma Regional
Stage, Pridoli, Upper Silurian.
Localities: Äigu, Saaremaa, Estonia; the following bore holes in Estonia: Ohesaare,
depth 64.65 m, and in Latvia: Kolka-54, depth 261.3-261.5 m; and north bank of
Mikhailovsk Pond, Ufa amphitheatre, western slope of Central Urals, Russia.
Emended diagnosis: small scales (up to 1.5 mm deep and 0.3 mm long), curved and
straight dentine ridges ending posteriorly in a pointed tip and reaching the posterior
margin of the scale or beyond. The ridges carry very oblique, short, lateral ridgelets
angled at 20° or less to the crest. The ridges have a narrow, smooth and flat crest. The
posterior-most pair of ridgelets form a wider, flattened, wing-like structure.
Description: Märss (1986) figured five specimens and chose an elongated low scale as
the holotype (Märss 1986: pl. 34, fig. 10). Specimen GIT 232-412 (Märss 1986: pl.
34, fig. 8) represents a typical scale (Fig. 4 A, B) with broad, dorsally overlapped area
(“peg”); the scale has a weakly developed keel on the inner side. Vascular canals open
as pores around the ridges as in L. superbus. A median ridge scale (probably from the
dorsal midline) is shown in figure 11 (Märss 1986: pl. 34). Specimen GIT 232-415
(Märss 1986: pl. 34, fig. 9) looks like a scale, but it is a plate with a convex posterior
border and a flat inner surface; it carries the typical ridges with oblique ridgelets and a
wing-like posterior-most pair of ridgelets.
Fig. 4. Lophosteus connexus; Pridoli, Upper Silurian; Vaivere outcrop, Saaremaa, Estonia.
A, scale GIT 232-412; B, detail of A. SEM pictures, scale bars equal 100 µm.