Dictyostelid cellular slime moulds of the United Kingdom : isolation, identification and distribution.
Soil samples were collected and processed, mainly from woodland, but also from
non-woodland soils, particularly from designated Sites of Special Scientific
Interest. The survey focussed on the East Anglian region and the north of
England and Scotland, where Cavender & Raper's semi-quantitative isolation
method was used to assess dictyostelid population densities at the sites surveyed.
Qualititative species data only were also obtained from additional soil samples
collected from within the United Kingdom.
Isolation and identification methods were examined, and a total of 12 described
species were recorded. Of these 12 species, 5 were the first reports for the United
Kingdom, D. fasciculatum, D. polycarpum, P. candidum, D. implicatum and D.
septentrionalis, the latter two being the first isolations of these species in Europe.
In addition, one new species of Polysphondylium was isolated from soil collected
from Silverdale Glen in the Isle of Man and a putative new Dictyostelium species
was isolated from Thetford Forest, Norfolk. The variant, D. aureo-stipes var.
helvetium, was also reported for the first time and one D. mucoroides variant was
encountered at two sites. Images are presented ofall of these, together with a
detailed description of the new species of Polysphondylium, and the
characteristics of the putative new Dictyostelium isolate, together with
measurements of both of these, which were obtained using image analysis.
Allozyme electrophoresis was employed in an attempt to establish the affinities of
the new species of Polysphondylium.
A relational database was designed and constructed to facilitate identification of
isolates and analysis of dictyostelid population densities.
The data obtained during this survey were combined with that obtained by Turner
(1978) to present a complete species distribution list of dictyostelids, to date, in
the United Kingdom.
A dictyostelid culture collection has been constructed, containing representatives
of most of the strains encountered during this survey, which is available for future