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C.G.Miller, T. Marss, H. Blom. New anaspid material from Britain and Estonia
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(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