. Bulletin of the Natural Histort Museum. Geology series. PALYNOLOGICAL ZONATION OF MID-PALAEOZOIC, NW SPAIN 125 LP19), Geras (sample Ger 12) and La Vid (sample LV 10). This spore event occurs in England in sections from Hereford and Worcester in strata below the micrornatus - newportensis (MN) Zone. Although the Aneiiwspom Sub-Biozone in the Cantabrian Mountains occurs a little below (c. 5 m) the occurrence of the typical Lochkovian chitinozoans Eisenackitina hohemica and Angochitina tsegelnjucki (Geras), we regard the base of this Sub-Biozone as close to the Silurian/Devonian Boundary (Richa
. Bulletin of the Natural Histort Museum. Geology series. PALYNOLOGICAL ZONATION OF MID-PALAEOZOIC, NW SPAIN 125 LP19), Geras (sample Ger 12) and La Vid (sample LV 10). This spore event occurs in England in sections from Hereford and Worcester in strata below the micrornatus - newportensis (MN) Zone. Although the Aneiiwspom Sub-Biozone in the Cantabrian Mountains occurs a little below (c. 5 m) the occurrence of the typical Lochkovian chitinozoans Eisenackitina hohemica and Angochitina tsegelnjucki (Geras), we regard the base of this Sub-Biozone as close to the Silurian/Devonian Boundary (Richardson. Rodriguez & Sutherland, 2000). This correlation is based partly on comparisons with material from Podoliadescribed by Arkhangerskaya( 1980). In Podolia, below the base of the equivalents of the MN Biozone (Chortkov Group), there is distinct spore assemblage in the Mitkov Formation (Borshchov Group). This lower assemblage probably contains non-papillate spores of the gtnu?, Aneurospora and is above the first occurrence of the graptolite Mo/!Ogra/j?(M (//ir/o/v);/^ H/!//bn«/.y providing support for the idea that the Anewrospora (A) Sub-Biozone is Devonian. Based on the distribution of key chitinozoan species, Paris & Grahn (1996) used the base of Motwgniptiis unifonnis unifonnis. the higher of the two critical graptolite subspecies, to mark the base of the Devonian. In particular Eisenackitina hohemica. also found by us in the Cantabrian Mountains, and other restricted chitinozoan species occur in the upper Tajna Formation along with M. unifonnis unifonnis. Although it is difficult to be certain, because of the nature of the spore illustrations (Arkhangel'skaya, 1980), this Lower Podolian spore assemblage appears to include non-papillate species/varieties oiAneurospora and may, therefore, be equivalent to the Aneurospora Sub-Zone. Assem- blages with tripapillate spores (Aneurospora/Streelispora'l) occur in the Chortkov Group c. 70 m above the Mitkov assemblage. Th
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