Calicium Corynellum (Ach.) Ach

Calicium corynellum (Ach.) Ach.

Rock Nail CALICIACEAE SYN.: Lichen corynellus Ach. (1803); Calicium paroicum Ach.; Strongyleuma paroicum (Ach.) Vainio non auct. (1799); Cyphelium chlorinum (Sten.) Krempelk sec.auct.ital.

Status: Nationally Scarce UK BAP Priority Species Lichens Red Data Book – Critically Lead Partner: Plantlife Endangered (1996) 3 / 233 10-km squares (2 in England, 1 in Scotland)

UK Biodiversity Action Plan:

These are the current BAP targets following the 2001 Targets Review:

T1 - Maintain all known populations. T2 - If biologically feasible, restore Bywell population to former extent.

Progress on targets as reported in the UKBAP 2002 reporting round can be viewed by selecting this species and logging in as a guest on the following web site http://www.ukbap.org.uk/asp/2002_LPLogin.asp

The full Action Plan for Calicium corynellum can be viewed on the following web site, http://www.ukbap.org.uk/asp/UKPlans.asp?UKListID=179

Contents

Status:...... 1 UK Biodiversity Action Plan:...... 1 1 Morphology, Identification, Taxonomy & Genetics...... 2 1.1 Morphology & identification ...... 2 1.2 Taxonomic considerations ...... 3 1.3 Genetic implications ...... 4 2 Distribution & Current Status ...... 4 2.1 World...... 4 2.2 Europe ...... 4 2.3 United Kingdom...... 5 2.3.1 England ...... 7 2.3.2 Northern Ireland...... 7 2.3.3 Scotland...... 8 2.3.4 Wales ...... 8 3 Ecology & Habitat Requirements ...... 8 3.1 Habitat...... 8 3.2 Humidity ...... 9

3.3 Site Management...... 9 3.4 Atmospheric pollution ...... 9 3.5 Position ...... 9 3.6 Substrate ...... 10 3.7 Aspect...... 10 3.8 Associated Species...... 10 3.9 Dispersal ...... 10 4 Threats ...... 11 4.1 Factors Threatening Survival & Dispersal...... 11 5 Management Implications ...... 13 6 Recommendations for Future Work ...... 13 7 References ...... 14 8 Acknowledgements ...... 15 9 Contacts ...... 15

1 Morphology, Identification, Taxonomy & Genetics

1.1 MORPHOLOGY & IDENTIFICATION

Description Calicium corynellum is a “pin-head” lichen with a distinctive, powdery (granular-leprose), yellowish-green thallus. The apothecia are black, sessile or more commonly short- stalked (usually no more than 0.5-0.6mm) and 3-5 times as high as the width of the central part of the stalk. The disc can reach 2.5mm diameter in sessile fruits, and the brownish exciple supports a well-developed, black dry-spore mass (mazedium). A faint yellowish pruina can be seen on the lower side of the exciple. (See figure 1)

Figure 1 - Line drawing of Calicium corynellum indicating main features (Fred Rumsey)

‘Pin-head’-

apothecium

Yellow-green thallus

Figure 2 - Calicium corynellum (by Jenny Duckworth)

Chemistry The thallus contains rhizocarpic acid. Scandinavian specimens also contain usnic acid, but in central Europe this is replaced by atranorin (Middleborg and Mattsson). Chemical reactions are all negative (Pd-, K-, KC-, UV-), and the apothecia are I-.

Microscopic characters Microscopic characters must be examined to confirm the identity of this species, particularly the shape and ornamentation of the spores. The photobiont is Trebouxia. Asci are clavate. Ascospores are 12-16 x 4-6µm, 1-septate with a distinct incision at the septum. The ascospore wall is thick with a distinct ornamentation of spirally arranged ridges when semi-mature, later becoming uneven and cracked.

Similar species C. corynellum is one of the few calicioid lichens, and the only one of its genus, that is found only on rock. However, it can be confused with:

Calicium viride – this species is similar in appearance and much more common. It grows on wood and bark, and the thallus is verrucose, taller apothecia (often 1.0- 1.9mm) that are 9-16 times as high as the width of the stalk and have a brown pruina.

Psilolechia lucida – a saxicolous species commonly found in the same habitat as C. corynellum. It resembles the sterile thallus but can be distinguished by its thicker, often rimose, thallus, bright yellow-green colour, and sometimes the presence of convex yellow apothecia. Under long wave UV light the thallus glows dull orange.

1.2 TAXONOMIC CONSIDERATIONS The close proximity of some C.corynellum populations to the very similar but corticolous C. viride has led to speculation that they may be the same species, however closer examinations of apothecial form and spore structure do not support this.

1.3 GENETIC IMPLICATIONS None.

2 Distribution & Current Status

2.1 WORLD Calicium corynellum is widespread but rare throughout temperate and hemiboreal parts of Western Europe, from Fennoscandia to Italy, and in western North America (Purvis et al. 1992, Nimis 1993, Wirth 1995, Ahti 1999, Tibell 2002). It is not known from Asia, Australasia or South America, although suitable habitats would seem to be available. This species is easily overlooked and may be under-recorded.

In North America C. corynellum was first collected from the Wells Gray Provincial Park in British Columbia. In the United States it has been recorded from scattered localities in California, Idaho and Montana. An earlier record from Arizona has recently been redetermined as Calicium montanum. (Kolb & Spribelle 2001).

Figure 3 - World distribution of Calicium corynellum

60N

30N

30S

60S

150W 120W 90W 60W 30W 0 30E 60E 90E 120E 150E

2.2 EUROPE Most of the European records are from Fennoscandia, where it is now rare and thought to be declining (Tibell 2002). Most of the known sites are in central and northern Sweden and in southern Finland; however some of these records are from the 19th century and have not been relocated.

The species has also been recorded from temperate areas of France, Germany, Moravia, Portugal, Tenerife, Italy (including Sardinia) and Turkey.

Table 1 - Country by country status of Calicium corynellum across Europe (*Country codes are taken from Flora Europaea as of 1964 with red data book listings where available [Definitions of the red list categories].)

Country Status notes Source(s) Au 1 record from Moravia (probably now in Austria) Tibell 2002 Az Britain [Br] Regarded as Nationally Scarce in Britain (occurring in 100 or fewer 10-km squares of the national grid). The species is known only from three sites in two stronghold areas. Bu Cz Da Finland [Fe] Scattered in Southern Finland Ahti et al 1999 France [Ga] Present Tibell 2002 GERMANY 2 sites in Baden-Wurttenburgs Wirth 1987 [Ge] Hb He Ho Hs ITALY [It] At least 8 sites in northern, central and southern Nimis 1993 Italy, also 1 site in northern Sardinia Tibell 2002 Ju Lu NORWAY 1 site in southern Norway Middleborg & [No] Mattsson 1987 PORTUGAL Present in Portugal and Tenerife Tibell 2002 [Po] Rm Rs(N) Rs(B) Rs(C) Rs(W) Rs(E) SWEDEN Rare in southern Sweden, scattered in central and Ahti et al 1999 [Su] northern Sweden. Turkey Present Tibell 2002

2.3 UNITED KINGDOM Overview In Britain Calicium corynellum has a northern distribution restricted to the millstone grit and limestone areas of south Northumberland and Midlothian. At present it is known only from artificial habitats in churchyards, where it has been recorded from four sites (3 in northern England, 1 in southern Scotland), and survives in three of these.

A thorough search of 24 suitable natural sites within 30 miles of the Northumberland populations has so far failed to locate any more, but this species is easily overlooked and probably under-recorded.

Calicium corynellum is classified as Critically Endangered in the Red Data Book for Lichens (Britain) (Church et al, 1996). At that time it qualified for this on three counts:

80% population decline in the last ten years

Recently recorded in fewer than ten 1x1km squares, with only site and in decline Small population of fewer than 50 mature individuals.

Since then three more sites have been discovered, but the original population appears to have been lost and the extant populations are much smaller, so the status should remain unchanged.

Table 2 - Present & former distribution of Calicium corynellum by vice-county

V-C. MODERN ADMINISTRATIVE TOTAL NUMBER OF DATE AND PLACE(S) OF LAST NO. COUNTY EXTANT SITES RECORD (POST-1990) / EXTINCT SITES 67 NORTHUMBERLAND 2 / 1 2002 (Whitfield, Bywell) 83 MIDLOTHIAN 1 / 0 2002 (Borthwick)

1 Figure 4 - British distribution of confirmed populations of Calicium corynellum 0

0 -2 -1 0 1 2 3 4 5 6

Table 3 - Records of Calicium corynellum – historical and extant

Locality County V.C. 10km Grid Date Rec. Herb. sq Reference * * Bywell St Northumberland 67 NZ06 NZ052620 1972 D B, D Peter Bywell St Northumberland 67 NZ06 NZ052620 1996 D Peter Bywell St Northumberland 67 NZ06 NZ052620 1999 D Peter Bywell St Northumberland 67 NZ06 NZ052620 18.2.01 E Peter Whitfield St Northumberland 67 NY75 NY778583 14.5.00 E B, E John Whitfield St Northumberland 67 NY75 NY778583 19.10.02 E John Borthwick Midlothian 83 NZ06 NT368596 2002 F Bywell St Northumberland 67 NZ06 NZ052620 16.5.02 E Andrew *Key to sources of records and herbaria: A - Natural History Museum, London; B - Royal Botanic Gardens, Edinburgh; D - Dr Oliver Gilbert; E - Janet Simkin; F - Dr Brian Coppins. A search of the literature and herbarium specimens has failed to reveal any historical British records.

2.3.1 ENGLAND The colony was first recorded by Dr. Oliver Gilbert in 1972, on the north wall of the 14th century tower at Bywell St Peter. At this time it was thriving, forming a large patch with thalli on 28 stones at 1-2.5m above ground level, and even spread onto the mortar between the sandstone blocks. There was a small outlier population on the west wall of the tower, round the corner from the main colony. This situation is lightly shaded by trees, and is often humid or misty due to its proximity to the River Tyne. The humidity was raised further by an overflowing roof gutter, the water from which hit a stone slab and splashed up onto the wall. In the 1990s this slab was replaced by a gravel soakaway and the gutter became blocked by vegetation, and the colony declined to less than 10% of its former size. In 1998 the stone slab was reinstated, but there was probably some physical damage to the remaining populations when the tower was scaffolded and repaired the same year. A tiny remnant persisted until 2001, but the thallus appeared dry and bleached, and there was no further development of the existing 8 small apothecia. The wall is now quite dry, and parts of the stone surface appear to have flaked off recently. The remaining lichens are in a poor condition. Lepraria incana is confined to a lower zone on the wall, and the remnants of Calicium corynellum appear to be dead.

A new colony appeared in 2002 at the adjacent churchyard of Bywell St Andrew, presumably as a result of dispersal from the remnant on Bywell St Peter.

A large population was discovered by Janet Simkin at St John’s Whitfield in 2000. The lichen is present and fertile on three headstones, in the north-west corner of the churchyard. A sterile green thallus had been noted on one of the same stones during the previous year, so it is possible that it may have only produced apothecia during the winter of 1999-2000. Possible sterile thalli on other headstones nearby are being monitored.

2.3.2 NORTHERN IRELAND Not recorded.

2.3.3 SCOTLAND Another large population was found by Dr Brian Coppins at Borthwick church in 2002. It is on two adjacent headstones, at the west end of the churchyard.

2.3.4 WALES Not recorded.

3 Ecology & Habitat Requirements

The ecology and habitat requirements of Calicium corynellum have been assessed from observations of existing British sites, recent literature and personal communications.

3.1 HABITAT C. corynellum is saxicolous, growing on siliceous rocks. The natural locations reported for it are all very similar, on steep or vertical rock faces that are protected from direct rainfall by rock overhangs but are in humid situations such as along rivers. Typically these sites are lightly shaded by trees and north-facing. (Purvis et al 1992, Church et al 1996, Tibell 2002).

The British sites are similar, but in the artificial situation of churchyards. The first recorded population was on the sheltered, north-facing wall of an ancient church tower, where it grew over the sandstone blocks on a part of the wall that was just above the splash zone from an overflowing gutter. This site is close to the River Tyne and often misty. When thriving this colony is even reported to have spread over the mortar between blocks. The wall is now much drier and the colony has been lost.

Figure 5 - sheltered, north- facing wall of an ancient church tower with remnant Calicium corynellum population

Trace of remnant population

The other three sites all have populations on large sandstone gravestones that are slightly leaning. The lichen grows on the underside and in the carving, where the surface is protected from the impact of direct rainfall and is less subject to physical weathering and surface flaking.

The habitat requirements, deduced from investigation of the British sites only, are summarised below.

Table 4 - Habitat features important to Calicium corynellum in Britain

Type Description Physical and Low altitude – below 250m topographical High humidity – frequent mists rising from a nearby river or stream Dry surface - vertical or slightly overhanging Aspect east or north Undisturbed by site management and visitors Substrate of coarse sandstone Mature stone surfaces that have been exposed to weathering for at least 90 years Height more than 50cm above ground level

Vegetation/structural Partly shaded by trees Growing over Lepraria incana Minimal competition from other lichens and algal/cyanobacterial growth

Chemical Free from pesticide and herbicide usage Relatively low atmospheric levels of SO2 and N

3.2 HUMIDITY In Britain Calicium corynellum is only known from churchyards. These sites are very similar, in that they are at a low altitude (below 250m), and are close to rivers or streams. They are unusually humid for eastern Britain, with frequent and prolonged mists which raise the humidity in the local area. This humidity is retained close to ground level by overhanging trees, predominantly sycamore, which also provide partial shade.

3.3 SITE MANAGEMENT Site management is minimal, with occasional mowing of the grass or light grazing by sheep, and no use of herbicides close to the stones. Although all the churches are still in use, services take place no more than once a week and the congregations are small, so disturbance to the site is minimal. The occasional visitors to the churchyards tend not to visit the more shaded areas where C. corynellum is present.

3.4 ATMOSPHERIC POLLUTION All the sites are in rural locations, and with few buildings nearby. As a result atmospheric pollution levels from both SO2 and N compounds are reasonably low.

3.5 POSITION Colonies are found on smooth sandstone surfaces that have been undisturbed and exposed to the elements for at least 90 years. The surface may be carved, and is

vertical or slightly leaning (by up to 10o), in which case the lichen is growing on the underside. It particularly favours areas of carving, and the inscriptions on the stones.

On gravestones C. corynellum grows on the underside and in the carving, where the surface drains quickly and is dry for much of the time. In this position the fragile apothecia are generally protected from the impact of direct rainfall, and the stone surface is less subject to physical weathering and surface flaking.

Although the host species is often present on the lower parts of the stone, C. corynellum is only found more than 50cm above the ground where it is less subject to competition from algae and cyanobacteria, and to grazing by slugs and snails.

3.6 SUBSTRATE The substrate at all the British sites appears to be the local coarse sandstone of Upper Carboniferous (Namurian) age, which in Northumberland is known as the Longhouton Grits. European records are from a wider range of substrates, including an argillaceous schist and gneiss, but these rock types are scarce in those areas of Britain that are otherwise suitable for C. corynellum.

3.7 ASPECT All the extant colonies are on the east faces of headstones, although the original at Bywell was on the north face of the church tower.

3.8 ASSOCIATED SPECIES All the known British populations are growing over Lepraria incana. This species is not tolerant of drought, and is restricted to damp surfaces protected by shade or overhangs. Competition from other lichens is limited in such situations, and overgrowth by algae and cyanobacteria is restricted by the lack of surface water. Successional development if the lichen community is only likely if there has been some change to the microhabitat.

Host species - C. corynellum is thought to be parasitic on other leprose lichens, particularly Lepraria species (Purvis et al 1992) and Haemotomma ochroleucum (Nimis 1993). The suggested relationship is that C. corynellum is not itself fully lichenised but is a parasymbiont parasite, forming a symbiotic relationship with the host’s photobiont. In Britain the host seems always to be Lepraria incana.

Associated species - Existing British populations are all closely associated with Lepraria incana. Other associated species are those typical of an acid sandstone substrate in a damp, slightly shaded environment, particularly Psilolechia lucida, Lecanora expallens, Parmelia sulcata and P. saxatilis, but also Ramalina farinacea, Rinodina genarii, Lecanora gangaleoides, L. caesiosora, L. dispersa, Parmelia glabratula fuliginosa, Hypogymnia physodes, Acarospora fuscata, Cetraria chlorophylla, Pertusaria corallina, and Porpidia tuberculosa.

3.9 DISPERSAL Dispersal is by ascospores. Unusually for lichenised ascomycetes, these are released passively from a dry-spore mass (mazedium) on the surface of the apothecium rather than being actively ejected into the air.

The ascospores are relatively large (12-16 x 4-6µm), elliptical in shape, with a thick, pigmented wall that is heavily ornamented. The ornamentation causes the spores to adhere to insects, bird’s feet or other contacts. It will also cause them to stick together and form clumps, which will only be released from the mazedium in exceptional circumstances (Tibell 1994).

Calicium species do not produce asexual dispersal propagules. Conidia are produced by some species, but these are generally thin-walled and non-pigmented and so are unable

to survive the prolonged desiccation and intense UV radiation of long distance aerial dispersal (Tibell 1994).

Given the position of most C. corynellum colonies, under trees and on steep rock faces beneath overhangs, the release of spores into the air above the tree canopy must be a rare event. Driving rain might occasionally reach the pin-head apothecia and knock the spores off, but most of these will then be washed to the ground. Insects and mites are probably the main vectors (B.J. Coppins pers.comm.), picking up the spores by contact and transporting them to other sites favoured by the animals. Generally these sites will be close by, but flying insects may be responsible for occasional long distance transport.

The spores are resistant to desiccation and UV radiation, so once away from the source lichen they should be able to survive for months. Successful germination to form a new colony will depend on the spore landing in an appropriate situation and on a compatible leprose lichen host. Germination to form new thalli may be favoured when spores are clumped together, but such clumps are less likely to be transported over a long distance than individual spores.

The infrequency of successful dispersal may go a long way to account for the rarity of this species. The dispersal strategy would suggest that new populations are most likely to occur close to the source of spores, and this is supported by the recent spread of C.corynellum from Bywell St Peter to Bywell St Andrew, only 200m away, and from one headstone at Whitfield St John to others within 20m. Colonies in the more artificial situation of a British churchyard are perhaps more likely to achieve long distance dispersal than those in a natural forest habitat.

4 Threats

4.1 FACTORS THREATENING SURVIVAL & DISPERSAL

Table 5 - Summary of the threats to the survival and spread of Calicium corynellum in Britain.

Type Threat

HABITAT DESTRUCTION Climate change Local habitat changes, particularly increase in or removal of tree cover Elevated sulphur or nitrogen levels Relocation of substrate changing the microclimate Pesticides affecting dispersal vectors Inappropriate collection

DAMAGE Chemical damage by fertilisers, herbicides or cleaning agents Physical damage – handling, animal damage and weathering

Climate change The effects of climate change on this species are difficult to predict, but as it occupies a narrow ecological niche it is likely to be sensitive to regional and global environmental changes. Some authorities predict an increase in precipitation for this area, and the increase in humidity could favour the further spread of this species. Changes in the local vegetation and invertebrate populations could affect both survival and dispersal.

Changes to the microhabitat C. corynellum needs a humid and slightly shaded environment, and so is generally found under trees. Any significant increase or reduction in the shade provided by these trees would lead to competition from other species, and affect both its survival and, by changing the local invertebrate populations, its dispersal.

Physical damage The pinhead apothecia are easily broken off by contact and the thallus itself is powdery and loose, so that any handling or contact with machinery is likely to cause severe damage. This is an immediate threat as many church authorities are now proposing to stabilize and repair any potentially dangerous gravestones. Even the handling or use of machinery to check their stability could be extremely damaging. In this area headstones of the 19th and early 20th centuries generally have a broad plinth at the base which ensures that they can tilt by several degrees before the centre of gravity is no longer over the base and the stone becomes unstable. The process of setting them in the ground has often caused them to lean slightly since they were new, and such stones should only be a cause for concern if the angle of lean is extreme or increasing, or if the ground is being undermined by animals. Monuments constructed in two or more parts are vulnerable to dangerous deterioration and should be examined more carefully, but this does not apply to any of the known C. corynellum sites.

In a churchyard physical damage can also be caused by children playing, adults reading inscriptions, and by sheep rubbing against the stones. Weathering causes flaking of the sandstone surface, but this only seems to have occurred at Bywell St Peter, where it may have contributed to the loss of this population.

Relocation Any action taken to relocate, reset or lay gravestones flat will change the microhabitat and be extremely damaging to the lichens on the stones, and can be expected to result in the loss of this species.

Chemical damage Contamination by fertilisers, herbicides or pesticides used on the surrounding vegetation, or by chemicals used to clean gravestones to reveal the inscription, can be very damaging to lichens. The restriction of this species to undisturbed sites where chemicals are not used in site management suggests that it may be particularly sensitive.

Pesticides Insecticides used in the vicinity of C. corynellum populations may also reduce populations of dispersal vectors.

Elevated nitrogen and sulphur levels Many lichens are known to be sensitive to elevated nitrogen and sulphur levels. The distribution and scarcity of this species suggests that it may be sensitive to these factors. Existing populations could be damaged by any increase in industrial activity or intensive agriculture in the near vicinity.

Inappropriate collection Known populations of C. corynellum are small and easily damaged. Collection should only be permitted when needed to verify identification, and then kept to a minimum. At present this is enforced by encouraging visiting lichenologists to be accompanied by the project officer when visiting the sites, but as the locations become better known this could become a problem.

5 Management Implications

Suggested management involves:

informing site managers and providing practical assistance when appropriate

minimisation of disturbance to the C. corynellum populations, whether physical or chemical

maintenance of the required microhabitat

monitoring existing populations and any threats to them

monitoring suitable sites nearby to detect any new populations soon after they become established.

None of the known sites of C. corynellum in Britain have any formal protection or are covered by national conservation schemes, so it is necessary to agree the management plan for each site in discussion with the site managers. The level of formality appropriate in each case will vary.

6 Recommendations for Future Work

Future work on this species in Britain should include the following:

Site management to minimize physical and chemical damage, and ensure that the microhabitat of each population is maintained

Monitoring existing populations

Survey for new and unrecorded populations

Research into aspects of the species ecology and dispersal that are at present poorly understood.

Site management Accidental damage to C. corynellum populations is inevitable unless site managers are kept informed about the location of colonies and any threats to them. Appropriate management practices, in which disturbance to the gravestones is minimized and the microhabitat is maintained by planned tree thinning and felling, and avoiding the use of chemicals, should be agreed for each site and documented in a site management plan.

The stability of headstones is an immediate concern in many graveyards, and it is essential that someone with detailed knowledge of the species is involved from an early stage when any safety review is carried out. Physical damage may occur during stability testing as well as during stabilization works, so it will be necessary for such work to be supervised. If remedial works are required, site managers may seek financial support to ensure that such works can be carried out in a sympathetic manner.

Monitoring Population sizes change rapidly and this species is particularly vulnerable to damage and small environmental changes, so monitoring of the existing populations should continue on an annual basis. This should include a search of suitable habitats in the near vicinity for new or unrecorded colonies, and an assessment of any threats to the site as a whole and the stones supporting C. corynellum in particular.

C. corynellum does not lend itself to easy monitoring, because its diffuse thallus makes it impossible to define what is a single plant. However, the abundance and vigour of populations can be measured by recording the extent of each colony and the number of apothecia (estimated for large populations).

Location of additional sites As a result of this autecological study a much better understanding has been gained of the habitat requirements of this species. Further work to locate populations of C. corynellum can be more accurately targeted on suitable sites, and is more likely to be successful.

Research Further research is needed into aspects of the ecology and life-cycle of C. corynellum, particularly

its relationship with associated leprose species identification of dispersal vectors substrate restrictions

7 References

Ahti, T. et al., (1999). Nordic Lichen Flora vol.1. Allen, M.A., (2002). Pers. comm. Auerswald, B., (1858). Drei anf Steinen wachsende Calycien. Hedwigia 21:12-14 Blatchley, I., (2002). Pers. comm. British Lichen Society, (2002). Churchyard Lichens Fact Sheet. BLS. British Lichen Society, (2002). Permanence and Change. Stonechat 9. BLS. Church, J.M. et al., (1996). Red Data Books of Britain and Ireland: Lichens Vol 1. Britain. Gilbert, O.L., (1980). A lichen flora of Northumberland. Lichenologist 12: 325-395 Gilbert, O.L., (1999a). Calicium corynellum Species Recovery Programme. English Nature. Gilbert, O.L., (1999b). Conserving Calicium corynellum. British Lichen Society Bulletin 85:19-22. Goward, T., (1999). The lichens of British Columbia. British Columbia Ministry of Forests, Victoria. Historic Scotland, (2001), Conservation of Historic Churchyards – A Guide for Practitioners. Kolb, A. and Spribille, T., (2001). Calicium corynellum (Ach.) Ach. In the United States, and Calicium montanum Tibell new for North America. Evansia 18(3):90-92. Local Authority Circular 23/18, (2001). Management of Unstable Memorials. Health and Safety Executive and Local Authorities Enforcement Liaison Committee. Middleborg, J. and Mattsson, J., (1987). Crustaceous lichenised species of the Caliciales in Norway. Sommerfeltin 5. Nimis, P.L. and Poelt, J., (1987). The lichens and lichenicolous fungi of Sardinia (Italy), an annotated list. Studia Geobotanica 7 suppl.1. Nimis, P.L. (1993) The lichens of Italy: an annotated catalogue. Museo Regionale di Scienze Naturali, Torino. 897pp. Purvis, O.W. et al., (1992). The Lichen Flora of Great Britain and Ireland. Natural History Museum, London. 710pp. Tibell, L.B., (1975). The Caliciales of boreal North America. Symb. Bot. Upsaliensis 21(2):1-128. Tibell, L.B., (1994). Distribution patterns and dispersal strategies of Caliciales. Botanical Journal of the Linnean Society 116:159-202. Tibell, L.B., (2002). Pers. comm. Wirth, V., (1995). Die Flechten Baden-Wurttenbergs, Teil 1. Eugen Ulmer, Stuttgart. 527pp.

8 Acknowledgements

Stephen Ward (SNH), Nick Brodin (EN), Deborah Spray (EN), Dr Brian Coppins (RGBE), Dr Simone Louwouff (NHM), Tim Charlson (CCT), John Blackett-Ord, Fr. Tom Emmett, Dr Brian Coppins (RGBE), Dr Simone Louwouff (NHM), Jill Sutcliffe (EN), Peter Lambley and especially Dr Jenny Duckworth (Plantlife) and Dr Oliver Gilbert for their support throughout the project.

This species dossier is supported by English Nature and Scottish Natural Heritage.

9 Contacts

Plantlife 21 Elizabeth Street, London, Jenny Duckworth (Jenny. SW1W 9RW [email protected]) Tel: 0207 808 0113 / 0119 Amanda Miller, ([email protected])

Janet Simkin First draft dated 5th January 2003 Last revised 24th January 2003