Building on the success of the now much appreciated and well-used A Field Key to Churchyard Lichens by the same author (2003), we are now provided with a companion volume to the lichens of the coasts and seashore of the British Isles. Like the churchyards the coast offers a wealth of substrata for lichens and is, for the most part, now readily accessible, given the recent introduction of new coastal paths.
In walking these paths, particularly along the rocky west coast of Britain, if lichens have never previously intruded into your life you cannot but help but be amazed at their wealth and diversity.
This is an ideal book for someone of an inquisitive mind wishing to develop a new acquaintance with lichens of the coast. It includes not just those species occurring on rock but is also useful along the non-rocky coast as it includes terricolous, lignicolous and species of an assortment of further coastal substrata such as plant debris. In its introductory sections it clearly explains what lichens are and the way in which a number of species respond to their environment by developing in distinct and easily observable zones. A brief section explains the impact of oil pollution and in this potentially very hazardous terrain advice is offered on safe methods of observing coastal lichens.
Three methods of species identification are provided. Firstly, the beginner will probably turn to the almost entirely good quality colour illustrations of 96 common and rare species on six pages of plates. Many of these were previously used in the excellent laminated Guide to Rocky Shore Lichens of this author, published by the Field Studies Council in their AIDGAP series.
Method two consists of a table of only the species that are illustrated, to which are attached four simple, readily observable descriptive characteristics and notes, the whole table being divided into seven blocks of species based on the growth form of the lichen. The crustose sub-table with just over 50 entries is perhaps the most challenging to use and might best be employed following an initial photographic match. It is easy to criticise these helpfully simple aids to identification but they do not pretend to be comprehensive or foolproof. However, the notes column in the identification table occasionally refers to the existence of a similar but not illustrated species though often makes no mention of the fact. It might have been preferable to take a little more space and at least register that there are “x” similar species that might key out here.
The third and most comprehensive method of identification consists of a key to over 400 species. Such a large key is made more manageable by being split into eight sections based on the growth form of the lichen. The largest section, consisting of the crustose species, is further subdivided into three, based on the position of occurrence on the shore combined with the type of ascocarp body. The keys are clearly laid out and line drawings are provided in the margin to augment the description. Technical terms are kept to a minimum and a useful glossary is provided to assist where such terms cannot be avoided. If all else fails then in a final section of six pages of notes is provided to assist in the identification of over 90 of the rarer coastal species not included in the main key should you have been fortunate to discover them.
The author over many years has been responsible, through the field courses he has run, for introducing many people to the study of lichens and the keys presented here have been tested and modified in the light of this experience. They offer one of the most pain-free and enjoyable ways for the beginner and even the somewhat more experienced lichenologist of identifying coastal lichens. Even if you possess the author's excellent Lichens an Illustrated Guide this publication offers a way round the often rather difficult to use main key to genera in that work.
As a key designed to be used in the field, microscopic characteristics are avoided. In this respect it differs from the keys produced by Fletcher (Reference Fletcher1975a, Reference Fletcherb) that employ both suits of characters. Fletcher (op cit) undoubtedly offers greater certainty of a successful identification but at the price of having to resort to microscopic examination and with a taxonomy that is now seriously out of date.
The Field Key to Coastal and Seashore Lichens will I hope open up the world of coastal lichens to those who have found the existing literature too hard to obtain or too technical to use. It is clearly printed on robust paper between shiny card covers and is likely to stand up to some of the weather the coast can produce. The spiral binding allows the pages to lie flat, a huge advantage in a book to be used in the field when hands are required to manipulate a lens and specimen at the same time. The author is to be congratulated on producing such a useful book at a competitive price. I for one will never be visiting the coast again without my copy.
