Lichens of the Meredith Range

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Lichens of the Meredith Range

Gintaras Kantvilas and Jean Jarman


Lichens of the Meredith Range

Gintaras Kantvilas Jean Jarman

Tasmanian Herbarium

Private Bag 4, Hobart, Tasmania 7001

A report to Practical Ecology Pty Ltd on behalf of Cradle Coast NRM

March 2011


INTRODUCTION The Meredith Range is situated in western Tasmania within an area bounded approximately by the Lower Pieman Dam Road to the south, the Pieman River and Corinna Road to the west and north, and by south-flowing tributaries of the Pieman River (e.g. the Stanley and Wilson Rivers) to the east. The range consists of undulating terrain with high points at Mt Meredith (810 m) to the north and Mt Livingstone (781 m) to the south; neither of these peaks is prominent from a distance and the whole area is very much “off the beaten track” for biologists and bushwalkers. However, the general area has, and continues to be, explored for minerals. There is no published information on the natural history of the Meredith Range nor any significant numbers of herbarium collections from there. The geology of the area is predominantly Devonian granite (Richley 1978). The whole range was heavily burnt during the Savage River Fire of 1982 (Barker 1991); there is also anecdotal information of possible multiple fires since that time.

METHODS The range was visited by helicopter on 2 February 2011. A single study site, about 3.5 km south-east of Mt Meredith, was selected on the basis of ease of landing; Mt Meredith is approximately 7 km south south-east of Savage River township. Methods involved a rapid reconnaissance and overview of the site to identify the major lichen habitats present. Multiple representatives of each habitat were then searched and collections made for identification (or confirmation of identification) in the laboratory. Identification was conducted using the standard methods of low and high-power microscopy, thin-layer chromatography of selected specimens, and comparison with published descriptions and reference herbarium specimens where necessary. Voucher specimens of all species recorded are lodged in the Tasmanian Herbarium.

GENERAL DESCRIPTION OF THE STUDY SITE The site encompassed a relatively small, irregular-shaped area on the upper slopes and ridge, its boundary dictated by terrain and distance from the landing spot. Altitude was about 760–780 m asl; co-ordinates at the landing spot were AGD 0356355E 5394580N. The landscape was hilly, with boulders and outcropping rocks of granite the predominant feature. The surrounding vegetation comprised buttongrass moorland, with taller, more heathy vegetation around the rocky outcrops, and some low open forest over scrub in patches apparently missed, or burnt lightly, by the last fire. The community comprised ‘standard’ buttongrass moorland (nomenclature after Jarman et al. 1988) with emergent Banksia marginata. Occasional gaps occurred in the moorland, exposing the ground surface and smaller

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ground cover species. Emergent, weather beaten Banksia skeletons, up to 3–4 m tall, were prominent throughout, their pale grey stems, in parts blackened by charcoal, slowly disintegrating in the harsh environment. Smaller, dead stems of Leptospermum up to about 1 m tall, bleached and devoid of all twigs, were also common. The buttongrass moorland was dominated by Gymnoschoenus sphaerocephalus, with mixtures of woody species and monocots, including Leptospermum nitidum, Sprengelia incarnata, Melaleuca squamea, Bauera rubioides, Boronia elisabethiae, Eurychorda complanata, Lepidosperma filiforme and Empodisma minor forming a very dense layer about 40–60 cm tall. Scattered low crowns of Banksia, and less commonly Hakea epiglottis, were emergent in this layer. In gaps, small herbs were visible, including Helichrysum pumilum and Stylidium graminifolium, occasionally Actinotus bellidioides, Drosera arcturi and Mitrasacme montana, and very rarely Oschatzia saxifraga. The fine-leafed sedges, Schoenus tenuissimus and Tetraria capillaris, and the fern ally Lycopodiella laterale were also common in the low ground layer. The vegetation was generally more heathy around the rocks. Most of the woody species in the moorland matrix were common, but shrubs such as Epacris serpyllifolia, Monotoca submutica, Agastachys odorata, Eucalyptus vernicosa, E. nitida and Cenarrhenes nitida were also present. Protected rock crevices supported small patches of tightly compacted Hymenophyllum marginatum, and less commonly, several other Hymenophyllum species.

GENERAL DESCRIPTION OF THE LICHEN FLORA Eighty-three species of lichen were recorded (Table 1). The lichen flora is generally typical of what would be expected in buttongrass moorland (see Kantvilas & Jarman 1988, Kantvilas 2007 for general descriptions), although the overall abundance and species richness, especially on trees and rocks, was lower than expected (based on past experience and qualitative observations). Major genera with respect to prominence and biomass are the ground-dwelling Cladia, Cladonia and Siphula. The flora comprises mostly rather weedy species that are able to cope with disturbance such as fire and life in dynamic conditions where succession of vascular plants occurs relatively quickly. There are also small numbers of more restricted species persisting in tiny, highly localised refugia within this landscape of disturbance (Kantvilas 2007). The main factors influencing lichen distribution in general are the macroclimate (rainfall, temperature etc), the nature of the vegetation communities (forest, heathland, moorland etc) in so far as this determines the substrates that might be colonised by lichens as well as determining the microclimate conditions (shade, moisture etc), and the underlying geology. The incidence of large scale catastrophic disturbance such as fire or land clearance is also critical, as is local disturbance such as windthrow or landslips. These factors determine what habitats are available for lichens. At the Meredith Range study site, the major habitats for lichens included

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peaty soil within the buttongrass moorland itself, emergent woody shrubs in the moorland and in scrubby copses, and large boulders and outcrops of bedrock, including peat-filled crevices found on the larger outcrops.

1. Soil In buttongrass moorlands, lichens compete with small vascular species or fill the gaps between the larger plants including buttongrass hummocks. Siphula decumbens is particularly prominent, forming ashen white carpets of tiny erect flattened lobes. The genus Cladia, with entangled, tubular, hollow, perforated lobes, also has its stronghold here. Tasmania is the world centre of speciation for this genus, and the Meredith Range site supports as many as eight of the 13 species known worldwide. In open, boggy areas, the dominant lichens tend to be Cladia moniliformis, Parasiphula jamesii and the brownish, tea-leaf like P. fragilis. The flora in better drained, elevated sites, such as near rotting, dead buttongrass hummocks includes the greyish coral lichen, Cladia retipora, the mottled yellow-brown C. sullivanii, as well as numerous species of Cladonia. The most common of these is the yellowish Cladonia southlandica, which forms dense mats of small scales (squamules) with erect, scattered, rather deformed trumpets. Also common is Cladonia capitellata, which forms compact tufts of erect, narrow, pale yellow branches.

Common soil-colonising lichens. Above: Siphula decumbens (left), one of the most conspicuous lichens in moorlands, forming extensive swards; Parasiphula jamesii (right), typically restricted to boggy areas. Below: Cladonia southlandica (left), forming extensive mats on well-drained peat or rotting hummocks; Cladia retipora (right), one of the most conspicuous lichens in moorlands.

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2. Trees and shrubs Emergent trees and shrubs in buttongrass moorland would be expected to support a rich epiphytic lichen flora, including some species typical of rainforest and eucalypt woodland. However, at the study site, all the living vascular plants appear to be too young to support any epiphytes at all, and the only habitat for such species is provided by dead, fire-killed plants. Most of these are Banksia, forming spreading, bleached skeletons, but there are also occasional dead eucalypts and tea-trees. This habitat is very species poor and its lichens are mostly inconspicuous. Trunk bases and stumps with soft, damp, rotted bark and wood, and sheltered by the surrounding sedges, support Cladia aggregata, C. schizopora, Cladonia rigida and Trapeliopsis granulosa. More elevated parts of the trees that are exposed to the sun and wind have a patchy flora dominated by tufts of the yellow Old Mans Beard (Usnea spp.), leafy Hypogymnia enteromorphoides and Hypotrachyna sinuosa, and Ramboldia

Top: Dead Banksia provides the main substrate for wood-colonising lichens. Below, left: Hypocenomyce australis is common on or near charcoal. Below right: Ramboldia stuartii, visible only as glossy black fruiting bodies, occurs on dead, bleached wood.

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stuartii, the last species discerned only by its fruiting bodies (apothecia) which look like tiny black specks. On or near patches of charcoal, Hypocenomyce australis is usually abundant. Careful searching also revealed minute scraps of a few normally epiphytic lichens (species of Mycoblastus and Pertusaria, Leifidium tenerum) but these minute thalli are interpreted more as struggling survivors from the last fire rather than active recolonisers. It is noteworthy that two of the most common epiphytes of buttongrass moorland, the crustose lichens Tasmidella variablis and Ramboldia laeta, were not recorded.

3. Rocks Rocks are extremely abundant and dominate the landscape at the study site. Normally these would represent by far the richest lichen habitat in buttongrass moorland, and an almost total coverage of the exposed surface by lichens is not unusual in Tasmania. At Meredith Range, however, the rocks have been very severely scorched by fire and most of their surfaces are bare. However, their mottled colour indicates that extensive mosaics of species were once present. Whereas some lichens occur directly on rock, others are found in sheltered, peat-filled crevices. Due to their markedly different ecologies and species composition, these two habitats are best considered separately.

Large rock outcrops are a major lichen habitat in buttongrass moorland. As well as the exposed rock surfaces, specialised habitats for more restricted species occur in sheltered overhangs and peat-filled crevices. The bright orange-red splashes of colour are the filamentous alga Trentepohlia.

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3a. Rock surfaces. The most common species by far is Paraporpidia leptocarpa, a highly variable crustose lichen discerned mainly by its flat, disc-like, black fruiting bodies that form irregular patterns following the microtopography of the rock surface. Occasionally this species also has a rusty orange thallus. Although many additional lichens were recorded, the distribution of these was very patchy and confined to local spots (often only a few centimetres across) where they had escaped the worst effects of the fire. Some of these species, and ones which may have been expected to be common there once, are the pale orange Hymenelia sp. (a common Tasmanian highland species that is yet to be named formally), the pale yellow Pertusaria lophocarpa and Poeltiaria coromandelica, the pale lilac Trapelia lilacea, the greenish Rhizocarpon geographicum, and the whitish Lecanora farinacea. Macrolichens are generally very scarce, although Umbilicaria cylindrica, a typical species of highland rocks, was found as one tiny remnant thallus, as were several species of the green, foliose genus Xanthoparmelia. As was the case with epiphytic lichens, it is noteworthy that three of Tasmania’s most common and widespread species, the crustose Ramboldia petraeoides, and the foliose Flavoparmelia haysomii and Parmelia signifera, were not recorded.

Lichens of exposed rock surfaces. Above: Yellow tufts of Usnea torulosa, surrounded by mosses, occur near white patches of the crustose lichen Lecanora farinacea. Left: Black specks marking the numerous fruiting bodies of Paraporpidia leptocarpa surround the circular greenish thallus of Xanthoparmelia mougeotina.

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A mosaic of lichen forms and colours on a rock surface. Species present include Xanthoparmelia xanthomelaena (yellowish green thallus), an undescribed species of Hertelidea (black and white speckled lichen), and Lecanora farinacea (white thallus).

Extremely fire-protected surfaces on the largest outcrops supported a few additional inconspicuous species such as Chiodecton montanum and several species of Micarea, whereas Lecanora polytropa was found on the tops of some rocks where birds perch and defaecate. Smaller rock outcrops, deeply shaded beneath shrubs and sedges, supported patches of the whitish Dibaeis absoluta. 3b. Peat-filled rock crevices. The largest rock outcrops tend to provide a degree of protection from fire and the extremes of climate. Their peat-filled crevices and shady underhangs represent a specialised habitat where rainforest or alpine species, probably relicts from a past vegetation, have survived. It is not unusual to find normally epiphytic species in such places, either directly on rock (Leifidium tenerum) or over mats of bryophytes (Coenogonium lutescens). The severity of the fire at Meredith Range appears to have markedly reduced this component of the flora, although noteworthy records included the alpine species Arthroraphis citrinella and Pertusaria flavoexpansa, several woodland species of Cladonia, and Lepraria yunnaniana, which colonises dry, shaded soil in the deepest overhangs. Such sites also support remnant individuals of some rainforest vascular species; for example, species of filmy ferns (Hymenophyllum).

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LICHENS OF SIGNIFICANCE Most of the lichen species recorded are common and widespread in Tasmania, but a small number of records is highly significant (see below). 1. Baeomyces rufus. This is a widespread temperate species, previously unrecorded in Australasia. The specimen from the Meredith Range lacks fruiting bodies but compares favourably with reference herbarium material from the Northern Hemisphere. It grew on peaty soil in a sheltered rock crevice. 2. Cladia sp. A specimen of Cladia was collected that appears to represent a species new to science. It is morphologically most similar to C. dumicola but differs in its chemical composition. Further collection and study are required to confirm its novelty and to formally describe it as new. It grows on peaty soil in buttongrass moorland. 3. Lithographa graphidioides. This widespread austral cool temperate species is known in Tasmania from only two other locations. It grew on moist rocks in the shelter of a large granite outcrop. 4. Rimularia intercedens. This species is known only from the British Isles and Scandinavia. The identity of the Tasmanian specimen requires confirmation via comparison with reliable reference material, but the material appears to display all the diagnostic features of this species as described in the literature. Such disjunctions between Tasmania and the cool temperate Northern Hemisphere are not rare but are nevertheless noteworthy.

ACKNOWLEDGEMENTS We thank Nic McCaffrey for his companionship in the field, Joy MacDonald for planning and logistics, and Jen Archer and Jen Evans for initiating the project.

REFERENCES Barker, M. (1991) The Effects of Fire on West Coast Lowland Rainforest. Tasmanian NRCP Report No 7. Forestry Commission, Tasmania, and Department of Arts, Sport, the Environment, Tourism and Territories, Canberra. Jarman, S.J., Kantvilas, G. & Brown, M.J. (1988) Buttongrass moorland in Tasmania. Tasmanian Forest Research Council Inc., Hobart. Research Report No. 2. Kantvilas, G. (2007) Lichens: an overlooked Lilliput in Tasmania’s Buttongrass moorlands. Australasian Plant Conservation 16 (3): 18–19. Kantvilas, G. & Jarman, S.J. (1988) Lichens of buttongrass (Gymnoschoenus) moorland in Tasmania. Papers and Proceedings of the Royal Society of Tasmania 122 (2): 1–17. Richley, S.R. (?1978) Land Systems of Tasmania Region 3. Tasmanian Department of Agriculture, Hobart.

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Table 1. Lichens recorded from the Meredith Range, February 2011. wood Aptrootia robusta (P.M. McCarthy & Kantvilas) Aptroot Arthroraphis citrinella (Ach.) Poelt var. catolechioides Obermayer Baeomyces heteromorphus Nyl. ex C. Bab & Mitten Baeomyces rufus (Huds.) Rebent. Chiodecton montanum Thor Cladia aggregata (Sw.) Nyl. Cladia deformis Kantvilas & Elix Cladia dumicola Kantvilas & Elix Cladia moniliformis Kantvilas & Elix Cladia mutabilis Kantvilas & Elix Cladia retipora (Labill.) Nyl. Cladia schizopora (Nyl.) Nyl. Cladia sullivanii (Müll. Arg.) W. Martin Cladia sp. Cladonia capitellata (Hook.f. & Taylor) C. Bab. var. capitellata Cladonia corniculata Ahti & Kashiwadani Cladonia ochrochlora Flörke Cladonia pleurota (Flörke) Schaer. Cladonia pyxidata (L.) Hoffm. Cladonia rigida (Hook.f.& Taylor) Hampe var. rigida Cladonia southlandica W. Martin Cladonia subsubulata Nyl. Cladonia tenerrima (Ahti) S. Hammer Cladonia ustulata (Hook.f. & Taylor) Leighton Coenogonium lutescens (Vezda & Malcolm) Malcolm Dibaeis absoluta (Tuck.) Kalb & Gierl Fuscidea subasbolodes Kantvilas ?Gyalidea cf. fritzii (Stein) Vezda ?Hertelidea sp. Hymenelia sp. Hypocenomyce australis Timdal Hypogymnia enteromorphoides Elix Hypogymnia lugubris (Pers.) Krog Hypotrachyna sinuosa (Sm.) Hale ?Immersaria athroocarpa (Ach.) Rambold & Pietschmann Lecanora farinacea Fée Lecanora lugubris (C.W. Dodge) D.J. Galloway Lecanora polytropa (Hoffm.) Rabenh. Lecidea sarcogynoides Körb. Lecidea cf. xylogena Müll. Arg. Lecidella sp. Leifidium tenerum (Laurer) Wedin Lepraria yunnaniana (Hue) Zahlbr. Lithographa graphidioides (Cromb.) Imshaug ex Coppins & Fryday Micarea magellanica (Mull. Arg. Fryday Micarea cf. ternaria (Nyl.) Vezda Micarea sp.

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Table 1. Continued. wood Mycoblastus coniophorus (Elix & A.W. Archer) Kantvilas & Elix Mycoblastus kalioruber Kantvilas Paraporpidia leptocarpa (C. Bab. & Mitt.) Rambold & Hertel Parasiphula fragilis (Hook.f. & Taylor) Kantvilas & Grube Parasiphula georginae (Kantvilas) Kantvilas & Grube Parasiphula jamesii (Kantvilas) Kantvilas & Grube Pertusaria flavoexpansa Kantvilas & Elix Pertusaria lophocarpa Körb. Pertusaria novaezelandiae Szatala Pertusaria pertractata Stirt. Poeltiaria coromandelica (Zahlbr.) Hertel & Rambold Polychidium contortum Henssen Psilolechia sp. Ramboldia blastidiata Kantvilas & Elix Ramboldia stuartii (Hampe) Kantvilas & Elix Rhizocarpon geographicum (L.) DC. Rhizocarpon sp. Rimularia intercedens (H. Magn.) Coppins Rimularia psephota (Tuck.) Hertel & Rambold Siphula decumbens Nyl. Siphula gracilis Kantvilas Steinia geophana (Nyl.) B. Stein Stereocaulon corticatulum Nyl. Trapelia coarctata (Sm.) M. Choisy Trapelia ?glebulosa (Sm.) J.R. Laundon Trapelia lilacea Kantvilas & Elix Trapeliopsis granulosa (Hoffm.) H.T. Lumbsch Umbilicaria cylindrica (L.) Delise ex Duby Usnea inermis Motyka Usnea oncodes Stirt. Usnea torulosa (Müll. Arg.) Zahlbr. Xanthoparmeila isidiotegeta Elix & Kantvilas Xanthoparmelia mougeotina (Nyl.) D.J. Galloway Xanthoparmelia stygiodes (Nyl. ex Cromb.) O. Blanco et al. Xanthoparmelia tegeta Elix & J. Johnst. Xanthoparmelia xanthomelaena (Müll. Arg.) Hale

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