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The Essex Naturalist
Clearly we will need to carry out a systematic survey of likely habitats in each
10km square before we can produce an accurate picture of Stonewort occurrence
within the county, hence the interim status of this account. Before embarking
on this systematic survey we need to get permission to investigate the largely
private reservoirs and lakes within the county and enlist the cooperation of
potential recorders. The deep water regions of lakes such as Gosfield, for
example need to be systematically investigated with a boat and grapnel. Such an
overall picture would be most valuable if it could be completed in a relatively
short space of time, to offset the sporadic aspects of charophyte distribution, and
the false impression of overall abundance created by accumulating large numbers
of sporadic records over the years. Nevertheless, the mere 20 records assembled
for the Flora of Essex, (Jermyn &. Adams, 1974) has already been expanded to
around 170, and a picture of relative abundance is beginning to emerge.
Chara vulgaris sensu lato, is the commonest taxon in the county, with var.
longibracteata the commonest variety, but Chara globularis var. globularis is also
common, and in Epping Forest (and probably elsewhere) so to is Nitella flexilis.
The systematic account is arranged as in Moore et al, 1986 using the same code
numbers for ease of reference, and the records have been shoehorned into the
most appropriate varietal forms. Where additional or intermediate characters have
been observed, these have been detailed under each record. In the introduction to
each taxon I have included its salient features and attempted to define its overall
status in Essex. Where specimens have been referred to from the Natural History
Museum Herbarium (BM) collection, they have, where available, been given the
specimen numbers quoted in the Atlas & Catalogue (Moore & Greene, 1983).
Acknowledgements
The author is very grateful to Nicholas F. Stewart, (BSBI recorder for
Stonewarts) for critically reading the manuscript, making helpful suggestions,
and for several additional records.
References
Allen, CO., 1950. British Stoneworts. Haslemere Natural History Society.
Gibson, G.S., 1896. Flora of Essex. London.
Groves, J. & Bullock-Webster, G.R., 1971. The British Charophyta. Vol.I & II. The Ray Society.
London. 1920 & 1924. Johnson Reprint Corporation.
Jermyn, S.T. & Adams, K. J., 1974. Flora of Essex. Essex Naturalist Trust.
Moore, J.A. & Greene, D.M., 1983. Provisonal atlas and catalogue of British Museum (Natural
History) specimens of the Characeae. Institute of Terestrial Ecology.
Moore, J.A., Tebbs, M. & Greene, D., 1986. Charophytes of Great Britain and Ireland. BSBI
Handbook No: 5. Botanical Society of the British Isles.
Leister, G.L. & West, W.R., 1989. The Green Alga Chara: A botanical enigma. Carolina Tips.
No: 3. Carolina Biological Supply Co.
Stewart, N.F. 6k Church, J.M., 1992. Red Data Books of Britain and Ireland: Stoneworts. Joint
Nature Conservation committee.
Wood, R.D. & Imahori, K., 1965. A revision of the Characeae. First part. Monograph of the
Characeae. Weinheim.