Lower Devonian spore assemblages from the Arbuthnott Group at Canterland Den in the Midland Valley of Scotland

Silurian and Lower Devonian plant assemblages from the Anglo‐Welsh Basin: a palaeobotanical and palynological synthesis

“…Amongst the most striking contrasts is the abundance of cryptospores (Table 3). In contrast to the Midland Valley assemblages, cryptospores (both laevigate and sculptured) have higher maxima in the floodplain deposits Lavender and Wellman (2002) record abundances of only 0-3%. As regards size, spores are small, often around 18 mm (range 11-62 mm) in the Anglo-Welsh area in the lower and middle MN Zone and therefore were readily dispersed by wind and water but, in what is a coarsening-upwards sequence, there is a dramatic increase in size of some of the spores in the overlying BZ Zone in that area.…”

“…Obviously, there are sufficient numbers of taxa in common to allow placement in the same palynological zone, but differences in proportions of taxa, together with presence/absence of certain taxa, may reflect local physiographic/topographic conditions, climate or even migration. Considering, for example, the Lower Old Red Sandstone sequences in the Midland Valley, they exemplify differences between the spore floras from the Scottish intermontane basin on the one hand, with thickness of sediment estimated as at least 1800 m (representing only the lower and middle MN Spore Zone) swept in from the Caledonian Mountain Chain to the north, and the external floodplain of England and Wales on the other hand where, in contrast, only c. 850 m of sediment accumulated in the same interval (Richardson 1967;Richardson et al 1984;Lavender and Wellman 2002). The most striking differences between the spore floras of the two areas are summarized in Table 3 and relate to comparative abundances of various spore types, timing of appearance of taxa and size.…”

“…The last two categories named have not been found in the Anglo-Welsh area at these low stratigraphic levels. A further difference between Scotland and the Anglo-Welsh region involves the relative abundances of species of Aneurospora and Streelispora-the two genera being rarer in Scotland Lavender and Wellman 2002). Amongst the most striking contrasts is the abundance of cryptospores (Table 3).…”

Archetypally Siluro-Devonian ichnofauna in the Cowie Formation, Scotland: implications for the myriapod fossil record and Highland Boundary Fault Movement

“…The palaeobiological and tectonic implications of the formation are presently understood on the basis that the unit is late Wenlock in age (Lavender and Wellman, 2002), but recent U-Pb dating of ash bands within the formation suggests that it may in fact be Early Devonian (Suarez et al, 2017). The Wenlock age is determined from palynomorphs retrieved from the inland exposures of the formation at Carron Water (Bridge of Graham) [NO 825853] and Carron Wood [NO 807848] (Marshall, 1991;Wellman, 1993;Lavender and Wellman, 2002).…”

“…The Wenlock age is determined from palynomorphs retrieved from the inland exposures of the formation at Carron Water (Bridge of Graham) [NO 825853] and Carron Wood [NO 807848] (Marshall, 1991;Wellman, 1993;Lavender and Wellman, 2002). However, the inland outcrop is poorly exposed in comparison to coastal exposures north of Stonehaven, from which most interpretations of sedimentary facies, and all macrofossil samples, are known.…”