Taitia catena Crookall, 1930

Candela, Yves & Crighton, William R. B., 2019, Synoptic revision of the Silurian fauna from the Pentland Hills, Scotland described by Lamont (1978), Palaeontologia Electronica (19 A) 22 (2), pp. 1-45 : 38-39

Taitia catena Crookall, 1930 ;

described on page 279

Figure 20.9 ; see also Figure 20.2 , 4 for labels

NMS G. 1979.45.1: the locality, although not clearly cited by Lamont, may be the “Gutterford Burn flags”, which corresponds to the lower part of the Deerhope Formation (possibly localities R 189 to R 195).

The specimen figured here ( Figure 20.9 ) is possibly the specimen described by Lamont, but in the absence of an illustration, this is putative. The label figured on Figures 20.2 and 20.4 (recto and verso) mentions both Mirmor and Taitia , which indicates that both specimens may be on the same sample (here NMS G. 1979.45.1). Lamont speculated on the possible affinity of Taitia catena (see page 279) and thought it could represent the “reproductive bodies” of a Tunicate ( Figure 20.4 ).

This taxon was tentatively assigned to the Plantae by Crookall (1930) and does not resemble the specimen shown here. We suspect Lamont to be mistaken.

The structure figured here shows the characteristic reticulate scuplture of Dictyocaris alga (see for example Botting (2007), text-fig. 4.2 B). Dictyocaris ramsayi Salter, 1860 is recorded from the NEI in the lower part of the Deerhope Formation, but also from the Lower Silurian of Lesmahagow (30 km SE of Glasgow). This species is characterised by “a variable ornament of irregular polygonal embossing, sometimes with polygons (1–2 mm across) combining to form meandering channels” (Botting 2007, p. 39), which is present in the present specimen. Therefore, Lamont’s specimen is here identified as Dictyocaris ramsayi Salter.

Figures

FIGURE 4. 1–5: Cyrtolites (Balsillia) limbus Lamont, 1978, from the Deerhope Burn; 1: side view of specimen NMS G.1876.42.72.2 from the Henderson Collection; 2: handwritten label associated with the specimen (right hand side); 3–5: handwritten labels discussing the possible affinity of the specimen (see Lamont 1978, page 247) – note that the information on some labels is crossed out by Lamont. 6–9: Phanerotrema tomkeieffi Lamont, 1978, from the Deerhope Burn; 6: side view of specimen NMS G.1876.42.58.1 from the Henderson Collection; 7–9: handwritten labels associated with the specimen. Scale bars: 5 mm (figures 1, 6).

FIGURE 20. 1–4: Mirmor andreae Lamont, 1978, from the Gutterford Burn, lowest Deerhope Formation; specimen NMS G.1979.45.1, original external mould (1), the latex cast of this specimen is figured by Lamont on plate XXXII, figure 1, and counterpart (3) registered as NMS G.2001.100.4; 2, 4: handwritten labels with information on the specimen. 5–8: Scotoharpes domina Lamont, 1948, from the Henshaw Burn (possibly R98), Wether Law Linn Formation; 5, 8: close-up of handwritten label (5) glued on specimen NMS G.1978.61.547 (image 8), which was not figured in Lamont (1978); 6, 7: close-up of cephalon (part and counterpart). 9: Taitia catena Crookall, 1930, from the Gutterford Burn, lowest Deerhope Formation; specimen NMS G.1979.45.1, near bottom right of Mirmor andraea on Figure 20.1; Figures 20.2 and 20.4 relate also to this species. Scale bars: 10 mm (figures 1, 3, 8); 5 mm (figures 6, 7); 2 mm (figure 9).