LAYOUT OF SPECIES ACCOUNTS

Sequence, numbering and nomenclature of taxa are based on the latest Census Catalogue of the British Bryological Society (Hill et al. 2008). Nomenclature, delimitation of taxa and synonyms also take into account the publications by Blockeel & Long (1998), Corley et al. (1981), Corley & Crundwell (1991), Corley & Hill (1981), Grolle & Long (2000). Hill et al. (1991, 1992, 1994), Paton (1969a, 1999), Schumacker & Vána (2000) and Smith (1978, 1990, 2004) and sometimes other more recent research literature.

The heading for each taxon contains the following information (†Threat categories are based on the revised list by Hodgetts 2011, replacing those in the British Red Data Book by Church et al. 2001).

 

ALIEN           Thought to be an introduced species in British Isles

CR                  Critically Endangered †

EN                  Endangered †

LS                   Locally Scarce (taxa recorded post-1950 from four or fewer sites in Cornwall

                        or Isles of Scilly, but which are not NR or NS)

NR                  Nationally Rare (recorded post-1950 in 1–15 hectads in Britain, mainly following list by Preston 2010, with data

                        on infraspecific taxa from other sources)

NS                   Nationally Scarce (recorded post-1950 in 16–100 hectads in Britain,

                        following list by Preston 2006 with additions by Preston 2010: 33, i.e.

                        excluding recent additions to British list and most infraspecific taxa)

S                      Recorded in Isles of Scilly (see Paton & Holyoak 2005)

s. l.                   sensu lato, i.e. aggregate species (comprising two or more taxa)

s. str.                sensu stricto

S8                    On Schedule 8 of Wildlife & Countryside Act 1981

VU                  Vulnerable †

1                      Recorded in mainland vc1 [excludes Isles of Scilly]

2                      Recorded in vc2

vc1                  West Cornwall and Isles of Scilly (vice-county 1)

vc2                  East Cornwall (vice-county 2)

[ ]                     Pre-1950 records only

{ }                    Recorded only as weed of horticulture

 

Each species account gives information in the following sequence:

 

SYNONYMS: see note above.

 

FLORISTIC ELEMENT: A note summarises the European distribution as a whole, coded as a Biogeographic 'element' (cited from Hill et al. 2007, which is based largely on the detailed account by Hill & Preston 1998), e.g. 'Temperate Oceanic' or 'Mediterranean-Atlantic European'.

 

FIRST RECORDS: (marked*) for vice-county *1 or *2, or updated records (for taxa unrecorded for fifty or more years, marked +1 or +2.

 

HABITATS: All data refer strictly to author's observations in Cornwall and the Isles of scilly [C&S], unless otherwise noted. Available data are briefly summarised for rare species. For those that are commoner, information is given on the following topics: growth form (i.e. tufts, turfs, cushions, mats, wefts: adopting terminology of Hill et al. 2007), substrate types, water relations, preferences for insolated or shaded sites; main kinds of habitats occupied; any records of unusual habitats. In many cases where a diversity of habitats has been recorded the field notes are merely listed. This avoids rather glib summaries stating, e.g., 'wet places, shaded or unshaded, acidic or basic', when the bryophyte involved is nevertheless much less common than such a description might imply. Although generalised descriptions of habitat parameters are shorter and easier to understand than lists from field data, they can be seriously misleading when a taxon is later found to consist of several cryptic species each having different ecological preferences, as is proving to be the case with some of our bryophytes now molecular data are becoming available (e.g. Aneura pinguis

s. l.).

 

ASSOCIATES: All data refer strictly to the author's observations in C&S, unless otherwise noted. Associated plants (especially bryophytes) are noted, the lists often being first of 'Common associates' then of 'other associates'. Associates were defined as plants growing in immediate contact (i.e. normally touching the species in question, not merely species present 'nearby'). For relatively common bryophytes the lists are intended only to be indicative of the usual or commoner associates, not comprehensive. Scientific or English names of vascular plants mainly follow Stace (2010), with authors given only for those not included in his Flora. Generally, English names are used for familiar trees and shrubs, scientific names for the remainder of the flora.

 

OCCURRENCE OF VEGETATIVE PROPAGULES: All data refer strictly to author's observations in C&S, unless otherwise noted. Occurrence of bulbils, gemmae, tubers, deciduous leaves or other propagules is briefly noted.

 

OCCURRENCE OF SPOROPHYTES: All data refer strictly to author's observations in C&S, unless otherwise noted.  Sexuality (dioicous, autoicous, synoicous, paroicous, etc.) is sometimes noted based on Hill et al. (2007) or a reference that is cited. c.fr. = with sporophytes (even very immature or very old). Only four categories are used for frequency of occurrence of sporophytes: Common (present on 10-100% of occurrences of taxon), Frequent (on 1-10%), Occasional (on 0.1-1 %), Rare (on <0.1 %). Generalisations like these are only attempted where taxon itself has reasonably large number of records. Additional details are given for rare taxa or where sporophytes were seen <5 times in total. Normally records of capsules in each month (1 = January, 12 = December) are summarised as Immature, Dehiscing or Dehisced; exceptional or unusual records and those based on very few capsules are given in square brackets. For cleistocarpous capsules of some mosses records are given as Immature and Large immature capsules. For many liverworts occurrence of perianths is recorded in similar way to capsules. Months are summarised as, e.g. 3-6, only when there are records for all intervening months (thus, 3-6 = March, April, May and June).

 

Additional information on some species may consider:

 

NOTES ON TAXONOMY AND IDENTIFICATION: Given mainly where changes in taxonomy have affected distributional data, e.g. newly described or newly recognised taxa, or those notorious for being misidentified or where the characters used for identification have changed over the years.

SUMMARY OF RANGE AND STATUS: A brief summary of the range in Britain and Ireland ('B.I.') may be given, mainly based on Hill, Preston & Smith (1991-1994) and Hill et al. (2008); references to literature are only given for sources additional to these. Comments on the range in Cornwall and the Isles of Scilly (C&S) are sometimes given and intended mainly to amplify or explain the data shown on the tetrad map. Where relevant, 'Status' then considers evidence of changed abundance or range in C&S since the 1960s (sometimes mentioning a numerical Change index: see the final chapter); brief references to changes elsewhere in B.I. are also added where appropriate.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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