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Temporary road sections for the A303 bypass at Ilminster, Somerset, revealed Upper Pliensbachian and Toarcian sediments from an alternating limestone–marl facies, in marked contrast to the limestone-dominated Dorset coast succession. The lithostratigraphy is described, with the standard ammonite zonation providing chronostratigraphical correlation. The uppermost Pliensbachian (Spinatum Chronozone) and much of the Toarcian (Serpentinum, Bifrons, Variabilis, Thouarsense and Pseudoradiosa chronozones) of the classic Dorset coast Lower Jurassic sequence are represented by the Beacon Limestone Formation, formerly the ‘Junction Bed’ (a highly condensed carbonate deposit). The Tenuicostatum Chronozone is largely missing from the sequence. Elsewhere in southern and eastern England this interval is poorly or rarely exposed. The argillaceous units have yielded rich microfaunas and -floras (foraminifera, ostracods, calcareous nannofossils and palynomorphs), the biostratigraphical distributions of which are analysed and discussed in relation to contemporary evolutionary patterns and other UK records. This study provides an insight into the micro-biostratigraphy of the Late Pliensbachian to Toarcian interval for onshore southern England.

John Eustace Whittaker was born near Burnley, Lancashire on 25 September 1945 and educated at St Mary’s College, Black-burn. Despite being a devoted Lancastrian, fate has decreed that since leaving school he has spent the rest of his life elsewhere and he is now a resident of south Essex. His interest in earth science was stimulated by the Geography and Geology teacher at St Mary’s College, Ken James, and consequently he entered the then University College of Wales, Aberystwyth to read Joint Geography and Geology in 1964. John was, however, ‘rescued’ from the geographical side of things by the redoubtable Robin Whatley (TMS Honorary Member 2004) and, in 1967, commenced research under his supervision, at the same time striking up what was to become a lifelong friendship with him, and also with John Haynes. John’s doctoral work concerned living ostracods of coastal sites in southern England and his thesis, ‘The taxonomy, ecology and distribution of Recent brackish marine Ostracoda from localities along the coast of Hampshire and Dorset (Christchurch harbour, The Fleet and Weymouth Bay)’, was a monumental two volumes submitted in 1972. From this developed Marine and Brackish Water Ostracods (Athersuch et al., 1989), an important synoptic work still in regular use (if you can find a copy). Fate again took a hand when, in 1971, a position in the Natural History Museum, London became available, working with another formidable character, the late Geoffrey Adams – on foraminifera rather than ostracods! John worked at the NHM until his retirement in . . .

Recently, the monotypic ostracod genus Ankumia van Veen, 1932 was abandoned as nomen dubium by Jones (2003, p. 85) in favour of Platella Coryell & Fields, 1937 and a new combination was proposed for the type species of Ankumia, i.e. Platella bosqueti (van Veen, 1932). However, Ankumia bosqueti from the Maastrichtian of The Netherlands was introduced as an available taxon and, as documented by Jones (2003), the specific name is valid for recognizing the species in which ‘pathological individuals with retained moults’ occur. Therefore, there is no reason to treat Ankumia as nomen dubium. Yet, although there is no doubt about the cytherellid relationship of the species, two taxonomical questions still remain.(1) Do pathological individuals of cytherellids justify specific and/or generic ranking? Certainly they do not, and demonstration of a corresponding ‘normal’ species (including ‘pathological individuals’) among the associated cytherellids is wanting. On the other hand, if these pathological individuals can be proven as representing a discrete pathological genus, Ankumia remains as a valid genus to characterize the available species name bosqueti.(2) Why should Ankumia be abandoned in favour of Platella? When van den Bold (1967, pp. 306, 308) compared Coryell & Fields’ original Gatún ostracod fauna with his own collection from the Neogene Gatún Formation in the Panama Canal Zone, he recognized the type species, Platella gatunensis, as a small-sized cytherellid moult. Over the years about a dozen small- and normal-sized cytherellid species from all over the world have been assigned to Platella, ignoring the questionable taxonomic . . .

The Thanetian Stage in the type area is composed of the Thanet Formation, the Woolwich Bottom Bed and the Oldhaven Beds. The Thanet Formation at the stratotype localities in southeastern England contains calcareous nannoplankton Zones NP 6/7 and NP 8. The Woolwich Bottom Bed and Oldhaven Beds are not zonable in the type area. The marine “Bottom Bed” of the Woolwich and Reading Beds is, however, assignable to Zone NP 9 outside the type area (at Clarendon Hill in Wiltshire).