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52 ADVANCES IN PALAEOICHTHYOLOGY Fig. 3. SEM pictures of fragments of scales in external view unless stated. All scale bars are 0.2 mm. A-F, Trimpleylepis concatenata gen. et sp. nov., fragments of scales from Ohesaare Borehole, Saaremaa, Estonia, depth 94.32-94.40 m, Ludfordian, Upper Silurian. A, GIT 384-1; B, GIT 384-2; C, GIT 384-3, D; GIT 384-4; E, GIT 384-5; F, GIT 384-6. G-H. Silmalepis cf. erinacea Blom, Märss and Miller, 2002, scale fragment from Man Brook, upper part of Prídolí Series, Upper Silurian, NHM P 66018(1): G, scale in external view; H, close up of sculpture. I- L, Family Rhyncholepididae Kiær, 1924 gen. et sp. indet., fragments of scales from Gardner’s Bank, c. 7m below Psammosteus Limestone, U. Downton Group, Prídolí, Silurian. I, GIT 384- 7. J; GIT 384-8; K, scale now sectioned and illustrated in Fig. 2D; L. GIT 384-9, visceral view.
C.G.Miller, T. Marss, H. Blom. New anaspid material from Britain and Estonia 53 (Fig. 1F) to more elongate in the holotype (Fig. 1C) and the Estonian material certainly falls within these variations. However, we prefer to classify the Estonian material under T. concatenata gen. et sp. nov. which has only one row of tubercles per scale, and three of the six scales are saddle shaped in cross section (Fig. 2E), whereas T. juncta gen. et sp. nov. scales show two to four rows of tubercles joined by more prominent ridges (Figs 1, 2C). The Ludlow age of T. concatenata gen. et sp. nov. suggests that the range of the genus Trimpleylepis should be Ludlow-Prídolí. Family RHYNCHOLEPIDIDAE Kiær, 1924 Silmalepis cf. erinacea Blom, Märss and Miller, 2003 Fig. 3G-H Material. One broken scale from Man Brook from uppermost Prídolí, Upper Silurian, Man Brook, near Trimpley, Shropshire, U.K. Description. Scale with wide smooth overlapped area; groove extends entire length of scale close and parallel to the sculpture margin on the main scale area. External sculpture of closely spaced fine tubercles of variable diameter followed by relatively closely spaced ridges that point into the gap between the following row. The ends of ridges are broken in this specimen but three distinct rows of ridges can be seen across the scale. Visceral side with single rib and no evidence of vascular canal openings. No histological sections have been made due to lack of material. Remarks. Precise identification of this scale is not possible due to lack of material and the preservation of the scale, which has broken spine-like ridges. Septentrionia mucronata Blom, Märss and Miller, 2002 has spine-like ridges that point between the next set of ridges, as the spines do in the material figured here. S. mucronata is also similar as it has a wide overlapped area, but it differs in having a narrow well developed ridge with granular sculpture (Blom et al. 2003, fig. 45g-h) in the position where there is a groove developed in the scale illustrated here. In our opinion the scale figured here (Fig. 3G, H) is much closer to Silmalepis erinacea Blom, Märss and Miller, 2002 that also has a coarse tuberculated to granular sculpture to the anterior of the main area of the scale (Blom et al. 2002, fig. 34a). The long spines inclined at a low angle to the main scale area of Silmalepis (Blom et al. 2003, fig. 34b) look to have broken off in the material figured here. The broken spines also have a concave upper surface as they do in S. erinacea. As the spines are broken, and because the scale figured here has a much broader overlapped area than typical S. erinacea, we consider the material certainly belongs within Silmalepis but identify S. erinacea with doubt. The material figured here extends the range of Silmalepis from mid Ludlow (Blom et al. 2003, fig. 10) to mid Ludlow-late Prídolí. RHYNCHOLEPIDIDAE gen. et sp. indet. Figs 2B, D; 3I-L Material. One intact scale, one small fragment, and two fragments that were used for thin sectioning, all from from Gardner’s Bank. Description. Scales with a narrow furrowed overlapped area that is incompletely preserved on most of specimens available. Low ridges on the main scale area are wellspaced with the ends nearest the anterior overlapped area slightly curved. Each ridge
Page 1 and 2: LATVIJAS UNIVERSITĀTES RAKSTI 679.
Page 3 and 4: LATVIJAS UNIVERSITĀTES RAKSTI 679.
Page 5 and 6: Contents Ervīns Lukševičs and Ģ
Page 7 and 8: ACTA UNIVERSITATIS LATVIENSIS, 2004
Page 9 and 10: Ervīns Lukševičs, Ģirts Stinkul
Page 15 and 16: Olga Afanassieva. Microrelief on th
Page 23 and 24: D.K. Elliott, E. Mark-Kurik, E.B. D
Page 47 and 48: C.G.Miller, T. Marss, H. Blom. New
Page 51: C.G.Miller, T. Marss, H. Blom. New
Page 59 and 60: H.-P. Schultze, T. Marss. Revisitin
Page 81 and 82: O.A. Lebedev. A new tetrapod from R
Page 101 and 102: E. Lukševičs, I. Zupiņš. Sedime
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E. Lukševičs, I. Zupiņš. Sedime
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J. Valiukevičius. Silurian acantho
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V. Pernegre, V. Dupret. Biostratigr
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Ž. Žigaite. New telodont from Tuv
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