Introduction
The Falkland Islands are situated in the South Atlantic Ocean between 51° and 53°S and 57° and 62°W, and 483 km from the east coast of continental South America (Fig. 1). They are an overseas territory of the UK and are also claimed by Argentina (as Islas Malvinas). They have an area of 12173 km2, making them the largest island group in the southern subpolar region, and consist of two main islands; East Falkland (Isla Gran Malvina) and West Falkland (Isla Soledad), with more than 230 smaller islands. Because they are relatively close to Argentina, they are considered to be continental islands but have a cold marine climate, with a small temperature range (−5 to +22°C), strong westerly winds, and are predominantly cloudy and humid. The mean January temperature is 8·8°C, and mean July temperature is 2·2°C (Moore Reference Moore1968). Rain occurs on more than half the days in any year, with an average annual rainfall of c. 610 mm yr–1 (Moore Reference Moore1968). Snow can occur throughout the year, except in January and February, but does not accumulate. The terrain is rocky and hilly, Mt. Usborne (705 m) being the highest point, with some boggy, undulating plains.
Fig. 1. The Falkland Islands, showing location of main collecting areas of Imshaug and Harris.
In the early Jurassic period, the Falkland Islands were situated in the centre of the Gondwana supercontinent, adjacent to the east coast of what is now South Africa. With the break-up of Gondwana in the late Jurassic (c. 167 mya), the Falkland Islands drifted to their present position off the coast of South America (McDowall Reference McDowall2005). Consequently, many of the geological features of the Falkland Islands are similar to those found in South Africa, with quartzite, sandstone and mudstone being the most common types of rock, and with igneous dykes of dolerite bearing witness to the final break up of Gondwana. No trace of this ancient connection with South Africa is apparent in the present-day biota of the islands, the main affinity being with Patagonia/Fuegia.
Although early botanists who visited the Falkland Islands, including J. D. Hooker (Hooker & Taylor Reference Hooker and Taylor1844; Hooker Reference Hooker1847), collected some lichens, the islands were not given much attention until the first decade of the 20th century when two important Swedish expeditions, both with Carl Skottsberg as their botanist, visited the islands and collected many lichens (Darbishire Reference Darbishire1912; Zahlbruckner Reference Zahlbruckner1917). However, as Skottsberg was not a specialist lichenologist, and these expeditions were part of larger expeditions aimed at collecting many different types of organism from a wider region, lichens were not comprehensively collected. This changed in the austral summer of 1968 when Henry Imshaug led an expedition, which also included his then graduate students Richard Harris (lichens) and John Engel (bryophytes), to investigate the cryptogamic biota of the islands. Between them, Imshaug and Harris made almost 3000 collections, representing by far the largest collection of lichens ever made from the islands (Imshaug Reference Imshaug1969). Although many of their collections were accessioned into the herbarium of Michigan State University (MSC), some were filed under provisional (in sched.) names, whereas others remained in temporary storage in cardboard boxes (Fryday & Prather Reference Fryday and Prather2001). Some of these in sched. names have since been published (e.g., Messuti & Archer Reference Messuti and Archer1999; Fryday & Common Reference Fryday and Common2001; Lumbsch et al. Reference Lumbsch, Divakar, Messuti, Mangold and Lücking2010), whereas others are referable to previously described species [e.g., Lecanora falklandica Imshaug in sched. is Xenolecia spadicomma (Nyl.) Hertel]. In 1999, the US National Science Foundation (NSF) made an award to Michigan State University to ‘re-activate’ the MSC lichen collection, thus facilitating access to this extensive resource, which also includes large collections from the Caribbean Islands, southern South America, and other island groups in the southern subpolar region (Fryday & Prather Reference Fryday and Prather2001). A further recent award by NSF has resulted in the label data from the entire accessioned lichen collection at MSC being entered into a database and made available online (Johnson et al. Reference Johnson, Fryday and Prather2005). Many new lichen records for the Falkland Islands resulting from these collections have already been published (Calvelo & Fryday Reference Calvelo and Fryday2006), and new species have also been described (Messuti & Archer Reference Messuti and Archer1999; Fryday & Common Reference Fryday and Common2001; Coppins & Fryday Reference Coppins and Fryday2006; McCarthy & Fryday Reference McCarthy and Fryday2009).
The only other herbaria to house a significant number of lichen collections from the Falkland Islands are those of the Swedish Museum of Natural History (S), which houses the collections from Skottsberg's two expeditions, and that of the British Antarctic Survey (AAS). The lichen collection at AAS contains c. 400 collections from the Falkland Islands, of which around half were collected by Ronald Lewis Smith between the years 1964–2000. However, it also includes collections from other members of the British Antarctic Survey, including R. W. M. Corner, D. C. Lindsay, and other researchers (e.g., R. Upson). The only other significant collection of which we are aware is that made by D. H. Dalby in 2000 (Dalby Reference Dalby2000). This consists of some 300 collections but is in the collector's private herbarium and was not made available to us.
Since 2008, we have been examining collections from AAS and MSC with a view to completing a comprehensive account of the lichens of the Falkland Islands. However, because of the large number of apparently undescribed species that we encountered, especially among the crustose genera, we realized that this was an unrealistic goal with the limited time and resources available to us. Consequently, we decided to publish this contribution of our preliminary findings so that the part of our work that has been completed is available to other researchers. We are aware of numerous other, apparently undescribed, taxa from the Falkland Islands that require further investigation before they can be formally described. These will be treated in future publications.
Material and Methods
This study is based upon specimens collected by Henry Imshaug and Richard Harris and housed in the herbarium of Michigan State University (MSC), and those in the herbarium of the British Antarctic Survey (AAS), mostly collected by Ronald Lewis Smith. Apothecial characteristics were examined by light microscopy on hand-cut sections mounted in water, 10% KOH (K), 50% HNO3 (N) or 0·15% aqueous IKI (I). Thallus sections were investigated in water, K and lactophenol cotton-blue. The ascus structure was studied in I, both without prior treatment and after pretreatment with K. Measurements of ascospores and paraphyses were made in K.
Thin-layer chromatography followed the methodologies of either Culberson & Kristinsson (Reference Culberson and Kristinsson1970), Elix & Ernst-Russell (Reference Elix and Ernst-Russell1993), or Orange et al. (Reference Orange, James and White2001). Nomenclature for apothecial pigments follows Meyer & Printzen (Reference Meyer and Printzen2000).
The main collecting areas of Imshaug and Harris are shown in Fig. 1.
Additional comparative material examined. Lecanora capistrata (Darb.) Zahlbr.: Falkland Islands (all collected by H. A. Imshaug & R. C. Harris (MSC) unless otherwise noted): East Falklands (Isla Gran Malvina): Port Louis, rocks along shore, 25 vii 1902, C. Skottsberg (S—lectotype); Stanley, UTM Grid 21F VC 3472, Empetrum-heath and outcrops on Tumbledown Mtn, 150–225 m alt., 1968, Imshaug 39774; Kidney Island, UTM Grid 21F VC 4880, coastal rocks on SE shore between landing bay and SE Pt, 1968, Imshaug 40611, 40621; Port William, UTM Grid 21F VC 4777, coastal rocks on N side of Hell's Kitchen, 1969, Imshaug 41628. West Falklands (Isla Soledad): West Point Island, UTM Grid 21F TD 4403– 4404, Hebe-scrub on steep slope and cliffs facing the Woolly Gut, 1969, Imshaug 40901; New Island, UTM Grid 21F TC 0164, polsterboden on summit of cliffs at NW tip opposite Landsend Buff, 90 m alt., 1969, Imshaug 41722; Fox Bay, UTM Grid 21F TC 9037, coastal rocks at Kelp Pt, 1969, Imshaug 42204.
Rimularia psephota (Tuck.) Hertel & Rambold: Chile: Straits of Magellan, Nohmck, 14 iii 1872, Hassler Explor.-Exped. T. Hill (holotype—FH).
The Species
Bryonora granulata Fryday sp. nov.
MycoBank No.: MB 564649
Bryonorae castaneae similis sed apotheciis saturate atrobrunneis, thallo granulato et acidum perlatonicum (non norsticticum) continenti.
Typus: Falkland Islands, East Falkland, Stanley, headwaters of Mullet Creek Stream, UTM 21F VC 3270 [−51·709500°–57·980333°], 200 ft [61 m], mosaic of Empetrum-heath & peat bogs, 30 January 1968, H. A. Imshaug (41439) & R. C. Harris (MSC-0108533—holotypus; BCRU, AAS—isotypi).
(Fig. 2)
Fig. 2. Bryonora granulata Fryday (Imshaug 41439—holotype). Scale=1·0 mm. In colour online.
Thallus effuse, widespreading to 5–10 cm, on soil; made up of flattish, pale brown to greyish areoles 0·2–0·3 mm across that soon break down into ±sorediose granules 0·03–0·05 mm across. Photobiont chlorococcoid, cells (5–)8–12(–15) µm diam.
Apothecia flat to slightly convex, lecideine, 0·3–0·4 mm diam., disc dark to reddish brown (especially when wet), proper margin 0·05 mm wide, persistent, darker than the disc and slightly raised. Hymenium 70–80 µm high, epihymenial zone 10 µm high, brown (K+ greenish brown, N+ reddish brown); paraphyses sparingly branched and anastomosing, septate, 2 µm wide, gradually widening to 3–4 µm at the apex, the upper 10 µm with pale brown pigment and a dark brown cap. Hypothecium composed of randomly arranged, brown pigmented hyphae (K+ greenish brown, N+ reddish brown), 4–5 µm wide; periclinally layered and narrower (2 µm wide) towards exciple. Exciple brown, composed of randomly radiating hyphae, 5–6 µm wide. Asci Lecanora-type, 45–50×12–15 µm, cylindrical, becoming sub-clavate; ascospores simple (rarely 1-septate), hyaline, ellipsoid to somewhat fusiform, 12–15(–16)×5·5–6·5 µm.
Conidiomata not observed.
Chemistry. C−, K−, Pd−; perlatolic acid by TLC.
Comments. This species is unique within the genus in having a thallus that contains perlatolic acid. The only other Bryonora species known from the Southern Hemisphere are B. castanea (Hepp) Poelt from New Zealand (Galloway Reference Galloway2007) and Antarctica (Poelt Reference Poelt1983; Øvstedal & Lewis Smith Reference Øvstedal and Lewis Smith2001) which has a thallus containing norstictic acid (K+ red), and B. peltata Øvstedal from Antarctica (Øvstedal & Lewis Smith Reference Øvstedal and Lewis Smith2001), which has a thallus containing protocetraric acid (Pd+ red).
Additional specimen examined. Falkland Islands: West Falkland: West Point Island, summit of Mt. Misery, UTM 21F TD 4201 [−51·374833°–60·703333°], 1100 ft [335 m], polsterboden, 1968, Imshaug (40697) & Harris (MSC, BG, NY, BM). East Falkland: Mt Usborne, The Gap, UTM 21F UC 7171 [−51·692333°–58·868167°], 900–950 ft [274–290 m], Cortaderia-heath, 1968, Imshaug (39895) & Harris (MSC, HO, M).
Bryoria mariensis Øvstedal, Common & Fryday sp. nov.
MycoBank No.: MB 564650
Thallus decumbens, ad 10 cm longus, brunneo-nigrus. Pseudocyphellae rarae, brunneolae. Soralia rara, globosa, subterminalia, grisea. Thallus acidum norsticticum continens. Pseudephebe pubescens similis, sed thallus cum pseudocyphellae et soralia.
Typus: Falkland Islands, West Falkland, Port Howard, summit of Mt. Maria, UTM 21F UC 2079 [−51·607500°–59·593500°], 2158 ft. [658 m], feldmark, 28 January 1968, H. A. Imshaug (41327) & R. C. Harris (MSC-0080870—holotypus).
(Fig. 3)
Fig. 3. Bryoria mariensis Øvstedal, Common & Fryday (Imshaug 41327—holotype). Scale=1·0 mm. In colour online.
Thallus fruticose, up to 10 cm wide, prostrate, no distinct main branches, thickest branches up to 0·4 mm diam. but usually<0·2 mm diam., branching isotomic dichotomous, young branches brown, old branches blackish; with pseudocyphellae and soralia. Pseudocyphellae rare, straight, up to 0·3 mm long and 0·05 mm broad, in young branches sometimes with medulla showing, otherwise closed and blackish. Soralia globose, 0·3–0·5 mm diam, concolorous with thallus, on end of branches or terminating small side-branches near branch tips; soredia 14–20 µm diam. Cortex approaching Nodobryoria-type (see Common & Brodo Reference Common and Brodo1995), with pseudoparenchymatous surface cells which look knobbly on the surface, below that prosoplechtenchymatous hyphae in a massive gelatinous matrix.
Chemistry. C−, K+ red (acicular crystals – microscope), Pd+ yellow; norstictic acid by TLC. Lichenan present in cell wall.
Distribution and ecology. Known only from grassland and Empetrum-heath, apparently not attached to rock, at three different localities from c. 500–650 m on Mt. Maria, West Falkland.
Comments. This taxon resembles Pseudephebe pubescens more than any known Bryoria sp., but a number of characters exclude that genus, such as the pseudocyphellae, the soralia and the presence of norstictic acid (see Brodo & Hawksworth Reference Brodo and Hawksworth1977). The genus Nodobryoria Common & Brodo (Common & Brodo Reference Common and Brodo1995) might be considered, due to the cortex type, but the cell walls of that genus lack lichenan (Common Reference Common1991).
Additional specimens seen. Falkland Islands: West Falkland: Port Howard, Mt. Maria, UTM 21F UC 2078-2079 [−51·608833°–59·595667°], 2000–2150 ft [610–655 m], feldmark and outcrops on summit ridge, 1968, H. A. Imshaug (41393) & R. C. Harris (MSC); ibid., slope above Castle Rock, alt 500 ft., on short dry grassland and Empetrum, 1992, R. I. Lewis Smith 8506 (AAS).
Bryoria chalybeiformis (L.) Brodo & D. Hawksw.
Two species of Bryoria have been reported previously from the Falkland Islands; B. austromontana P. M. Jørg. & D. J. Galloway and B. implexa (Hoffm.) Brodo & D. Hawksw. (Øvstedal & Lewis Smith Reference Øvstedal and Lewis Smith2004). In addition to the species described above, B. chalybeiformis is also reported here from the islands based on the following collection:
Falkland Islands: West Falkland: West Point Island, at summit of Bold Hill, 21F TC 0764 [−51·695333°–61·242333°], 527 ft. [161 m], Empetrum-heath, 1968, H. A. Imshaug (41794) & R.C. Harris (MSC).
Carbonea hypopurpurea Fryday sp. nov.
MycoBank No.: MB 564651
Carboneae vorticosae similis sed hypothecio K+ purpureo, thallo acida confluentica et 2′-O-methylperlatolica continenti.
Typus: Falkland Islands, West Falkland, Port Howard, outcrops on pass SW of Mt. Maria summit, UTM 21F UC 2078 [−51·6105°–59·5985°], 2000 ft [610 m], 28 January 1968, H. A. Imshaug (41294) & R. C. Harris (MSC-0136484—holotypus; BCRU—isotypus).
(Fig. 4A)
Fig. 4. A, Carbonea hypopurpurea Fryday (Imshaug 41372—holotype); B, Cliostomum falklandica (Imshaug 41673—holotype). Scales: A=0·5 mm; B=1·0 mm. In colour online.
Thallus effuse, widespreading up to 5 cm across, with black prothallus when adjacent to other lichens; areolate, areoles c. 0·2–0·5 mm across; pale grey, flat to slightly convex, cortex absent but with thin epinecral layer (c. 5 µm). Medulla I−. Photobiont chlorococcoid, cells 10–15 µm diam.
Apothecia frequent to scattered, lecideine, black, ±orbicular becoming angular, 0·4–0·6 mm diam., flat with an indistinct proper margin when young but soon becoming immarginate, margin±white pruinose when emerging from thallus but soon concolorous with disc, 0·05 mm wide, disc rough. Hymenium 60–70 µm tall; paraphyses unbranched, rarely with a short side branch, not anastomosing, non-septate, lax in K, c. 1·5 µm wide, slightly swollen to 3 µm at apex with upper 5–10 µm with blue-black pigment; epihymenium not granular, with blue-black pigment (N+ red: cinereorufa-green) often in clumps. Hypothecium brown, K+ purple. Asci ±cylindrical when young, becoming slightly clavate, Lecanora-type, 45–50×15–17 µm; ascospores hyaline, simple, oblong with rounded ends becoming slightly ellipsoid, (12–)15–17(–19)×5–6(–7) µm. Exciple poorly developed, blue-black pigmented.
Conidiomata not observed.
Chemistry. Confluentic and 2′-O-methylperlatolic acids by TLC.
Distribution and ecology. Carbonea hypopurpurea is currently known only from the mountains of West Falkland. The only associated species on the three collections are Pertusaria spegazzinii and Poeltidea perusta.
Comments. The holotype is densly covered with apothecia (Fig. 4A) but they are much more widely scattered in the two other collections. However, apothecial characteristics and thalline chemistry are identical and they are clearly referable to the same taxon.
Additional specimens examined. Falkland Islands: West Falkland: Port Howard, Mt. Maria, UTM 21F UC 2078-2079, 2000–2150 ft., feldmark and outcrops on summit ridge, 1968, H. A. Imshaug (41372) & R. C. Harris (MSC); Mt. Adam, basin E of summit, UTM 21F TC 8781, 1900–2000 ft., Cortaderia-heath, 1968, H. A. Imshaug (41106) & R. C. Harris (MSC).
Two other taxa described from the Falkland Islands or southern Argentina are also referable to Carbonea.
Carbonea agellata (Darb.) Fryday comb. nov.
MycoBank No.: MB 564662
Lecidea agellata Darb., Wiss. Ergebn. Schwedisch. Südpolarexpedit. 1901–1903. 4: 4 (1912); type: Falkland Islands, Port Louis, 25 July 1902, C. Skottsberg 130 (S!).
Carbonea subdeclinans (Müll. Arg. ) Hertel ex Fryday comb. nov.
MycoBank No.: MB 564652
Lecidea subdeclinans Müll. Arg. Nuovo G. bot. Ital. 21: 45 (1889).—Lecidella subdeclinans (Müll. Arg.) Hertel, Beih. Nova Hedwigia 79: 451 (1984); type: Argentina, saxicola in Staten Island [Isla de los Estados], Port Cook, 1888, C. L. Spegazzini 68 (G!).
In 1992 Hertel annotated an original specimen of Lecidea agellata in S (L988; sub Pertusaria alterimosa) “The type specimen of Lecidea agellata Darb. could not be traced yet. According to the protologue of L. agellata this taxon is characterised by e.g.: ‘apothecia immersa, thallus K−, margine nigro divisus' – characters which do not fit with those of this collection.” In 1994, Hertel annotated the specimen in S as Carbonea subdeclinans (Müll. Arg.) Hertel, but does not appear to have published this combination. The type collection of L. agellata has since been found and agrees well with the published description (including having immersed apothecia) and, in addition, has a KC+ orange thallus. Further, the additional material of L. agellata available in MSC shows a complete range in apothecia from immersed to sessile.
The asci of the type specimens of both L. agellata and L. subdeclinans have an apical cushion that extends to the top of the tholus (Lecanora-type) and, consequently, both species belong in Carbonea rather than Lecidella. Carbonea agellata appears to be relatively frequent on the Falkland Islands but is unknown elsewhere, whereas C. subdeclinans is known only from the type collection on Isla de los Estados and, given the similarities between the two species, it is tempting to include C. agellata as a synonym of C. subdeclinans. However, there are significant anatomical differences between L. agellata and the type specimen of L. subdeclinans (narrower ascospores, aeruginose epihymenium, orange-brown hypothecium) that suggest that the two species are not conspecific and, consequently, L. agellata and L. subdeclinans are here transferred to Carbonea as distinct species pending further investigation.
Additional specimens of C. agellata examined (all MSC and collected by H. A. Imshaug & R. C. Harris). Falkland Islands: East Falkland: Darwin Settlement, coastal cliffs on S side of Carcass Bay, Darwin Harbour, UTM 21F UC 6457, 1968, Imshaug 40233, 40246 B; ibid., Boca House on Brenton Lock, UTM 21F UC 6359, Imshaug 40308; Fox Bay, coastal rocks at Kelp Pt., UTM 21F TC 9037, 1968, Imshaug 42210 A. West Falkland: West Point Island, Hebe-scrub near The Waterfall, UTM 21F TD 4301, 100–300 ft., 1968, Imshaug 40688 A; Hill Cove, cliffs along sea at Point Settlement, UTM 21F TC 8390, 1968, Imshaug 41277.
Caloplaca megalariicola Øvstedal sp. nov.
MycoBank No.: MB 564653
Caloplacae buelliae similis, sed excipulo proprio pallido, ascosporis minoribus et hospitis (Megalaria) differt.
Typus: Falkland Islands, West Falkland, West Point Island, steep slope and cliffs facing the Woolly Gut, UTM 21F TD 4403-4404 [−51·355667°–60·670333°], Hebe-shrub, 22 January 1968, H. A. Imshaug (40896 p.p.) & R. C. Harris (MSC-0108536—holotypus).
Thallus inapparent.
Apothecia up to 0·4 mm diam., without algae in margin; disc rust red-orange-red, margin paler, orange to pale orange. Hymenium 65–75 µm high, uncoloured, not inspersed with oil droplets, paraphyses end cell enlarged to 3 µm diam; epipsamma medium coarse. Ascospores 8 per ascus, 12–16×5–7 µm, septum 3–4 µm broad.
Chemistry. Anthraquinones. Specimen too small for TLC.
Distribution and ecology. Known only from the type locality from Hebe-scrub on West Point Island, West Falkland. Lichenicolous on Megalaria grossa.
Comments. This species has some resemblance to Caloplaca buelliae Olech & Søchting, but differs in the pale margin of the apothecia, the smaller ascospores and the different host (C. buelliae is found on Buellia granulosa and B. anisomera on the South Shetland Islands and South Orkney Islands, see Øvstedal & Lewis Smith Reference Øvstedal and Lewis Smith2001). We have seen no similar species in Arctic areas (Hansen et al. Reference Hansen, Poelt and Søchting1987; Øvstedal et al. Reference Øvstedal, Tønsberg and Elvebakk2009). Previously no other Caloplaca has been found on Megalaria (U. Søchting, pers.comm. 2010).
Additional specimen examined. Falkland Islands: West Falklands: West Point Island, S end of the Woolly Gut, UTM 21F TD 4403 [−51·355667°–60·670333°], Hebe-shrub in steep sided coves, 1968, H. A. Imshaug (40738 A) & R. C. Harris MSC).
Cladonia flammea Øvstedal sp. nov.
MycoBank No.: MB 564654
Cladoniae luteoalbae similis, sed infra textura et hyphis angustibus squamulae primaerae differt, et acidae thamnolicum, decarboxythamnolicum, diacetylgracilliformicum, monoacetylgracilliformicum et skyrinicum continente differt.
Typus: Falkland Islands, East Falklands, Mt. Usborne, valley SW of Mt. Usborne, UTM 21F UC 7068 [−51·720667°–58·877500°], c. 200 ft. [61 m], Cortaderia heath and sandstone outcrops along stream, 10 January 1968, H. A. Imshaug (40175) & Harris (MSC-0108537—holotypus).
(Fig. 5A)
Fig. 5. A, Cladonia flammea Øvstedal; B, Lepraria malouina Øvstedal; C, Usnea campestris Øvstedal. Scales: A & B=1·0 mm; C=7·0 mm. In colour online.
Primary thallus as colonies covering several cm2 with scattered groups of squamules; squamules irregularly divided, ascending to flat-lying, upper side pale yellow-grey, wrinkled-sculptured, to 3 mm high and equally broad. Upper cortex uncoloured (in section), almost cartilaginous, 10–45 µm high, with elongated lumina oriented towards surface but walls often indistinct. Lower cortex absent. Medullary tissue with algae 350–370 µm high, ending in fairly uniform, short hyphae ends; hyphae c. 2·5 µm diam. Lower surface whitish, not arachnoid, yellow-orange at base, with indistinct veins.
Podetia rare, arising from squamule lamina, pale yellow-grey, tapering, with an open end, up to 6 mm high and 1 mm broad, corticated, in upper part with erect squamules, in lower part without squamules but cortex fissured. Uppermost part often eroded in some podetia.
Apothecia not observed.
Pycnidial gel brownish.
Chemistry. Thamnolic acid (major), decarboxythamnolic acid (minor), diacetylgracilliform acid (minor), monoacetylgracilliformin (trace) and skyrin (minor) (det. J. A. Elix 2009). The last three compounds are responsible for the yellow-orange pigmentation.
Distribution and ecology. Reported only from moribund bryophytes on the Falkland Islands.
Comments. Specimens of this taxon were mistaken for Cladonia luteoalba by Stenroos & Ahti (Reference Stenroos and Ahti1992, specimens in MSC and AAS seen), but that species has primary squamules with upturned margins and the lower side is uniformly pale sulphur yellow (usnic acid). In addition, the lower surface of the primary squamules of C. luteoalba is composed of a layer of anticlinal hyphae, c. 5·5 µm diam., which are loose towards the surface and have curling ends (resulting in an arachnoid lower surface, see photo in Stenroos 1990), and thamnolic acid is unknown in C. luteoalba (Stenroos Reference Stenroos1990; Øvstedal et. al Reference Øvstedal, Tønsberg and Elvebakk2009). Stenroos (1990) examined a large number of Cladonia luteoalba specimens, and found that the real podetia of C. luteoalba are escyphose and ecorticate.
The pigments which give the red-orange coloration are also found in Cladonia gracilliformis and C. bellidiflora (J. Elix, pers.comm. 2009), but these species are very different from C. flammea. At present, the affinities of this species within Cladonia are uncertain.
Additional specimens seen. Falkland Islands: East Falkland: Stanley, Mt. Tumbledown, alt 83 m, on soil, 2009, Soon Gyu Hong 091112-04 (AAS) (cf); Fish Creek, Goose Green, 5 m alt., 1963, Corner 98 (AAS). West Falkland: Fox Bay, outcrops on ridge NE from Sulivan House, UTM 21F TC 8952 [−51·839333°–60·061333°], 500 ft. [305 m], 1968, H. A. Imshaug (42366 B) & R. C. Harris (MSC).
Cliostomum falklandicum Fryday & Coppins sp. nov.
MycoBank No.: MB 564655
Ab omnibus speciebus generis Cliostoma habito saxicola et thallo atranoro unico continenti differt.
Typus: Falkland Islands, East Falklands, Port William, between Yorke Bay and Whalebone Cove, UTM 21F VC 4473 [−51·684000°–57·796000°], 75 ft. [23 m], outcrops on clay ridge, 1 February 1968, H. A. Imshaug (41673) & Harris (MSC-0111545—holotypus).
(Fig. 4B)
Thallus effuse, consisting of small, discrete patches up to 0·5 mm across, but forming larger patches in depressions; areolate, areoles c. 0·1 mm across; creamy white with a minutely arachnoid surface, cortex absent; often with a black, fimbriate prothallus. Medulla with numerous minute crystals giving it a pale brown colour, mostly dissolving in K. Photobiont chlorococcoid, cells 10–12 µm diam.
Apothecia lecideine, black, blue-black when wet, ±orbicular to slightly elongate, often with a wavy margin, 0·3–0·6 mm diam., flat to convex, ±immarginate; flat with a thin proper margin when young, margin 0·02 mm wide, concolorous with disc or unpigmented; disc rough. Hymenium 35–40 µm tall; paraphyses unbranched, sparingly branched towards apex, septate, lax in K, c. 2 µm wide, slightly swollen to 3 µm at apex, upper 5–10 µm with blue-black pigment; epihymenium granular with scattered minute colourless crystals, mostly dissolving in K. Hypothecium hyaline, composed of randomly orientated hyphae. Asci ±cylindrical when young, becoming clavate, Bacidia-type, 25–30×12–20 µm; ascospores hyaline, 1-septate, 9–11×4–5 µm. Exciple poorly developed with narrow anastomosing medullary hyphae with swollen, ±blue-black pigmented cortical cells; with numerous minute colourless crystals dissolving in K.
Conidiomata not observed.
Chemistry. C−, K+ yellow, Pd−; atranorin by TLC.
Distribution and ecology. Known only from the type collection, which is on the upper surface of a flat, angular quartzite pebble, c. 10×5 cm in area.
Comments. The dispersed thallus of this species is probably a result of the substratum upon which the lichen was growing and is probably not a diagnostic character. It is probable that other specimens of this species will have a more continuous, areolate thallus.
Two other taxa referable to Cliostomum, which were described from southern Argentina by Müller Argoviensis, were also collected on the Falkland Islands by Imshaug and Harris. These two taxa are currently misplaced in Catillaria and, although the chemical and morphological variation of these two taxa is still unresolved, the opportunity is taken here to transfer the two names to Cliostomum so that other researchers will be aware of them.
Cliostomum aeruginascens (Müll. Arg.) Fryday comb. nov.
MycoBank No.: MB 564656
Patellaria aeruginascens Müll. Arg., Nuovo G. bot. ital. 21: 47 (1889).—Catillaria aeruginascens (Müll. Arg.) Zahlbr., Cat. Lich. Univers. 4: 27 (1926) [1927]; type: ad corticum et lignum Berberidis in Staten Island, 1882, C. Spegazzini (G!).
Cliostomum violascens (Müll. Arg.) Fryday comb. nov.
MycoBank No.: MB 564657
Patellaria violascens Müll. Arg., Nuovo G. bot. ital. 21: 46 (1889).—Catillaria violascens (Müll. Arg.) Zahlbr., Cat. Lich. Univers. 4: 84 (1926) [1927]; type: ad corticum Drimydis in Staten Island et ad Ushuwaia in Beagle Channel, 1882, C. Spegazzini (G!).
Lecanora xantholeuca (Müll. Arg.) Hertel
New synonyms: Lecidea interrupta Darb., Wiss. Ergebn. Schwdeisch. Südpolarexpedit. 1901–1903. 4: 3 (1912); type: Falkland Islands, East Falkland, Port Stanley, 8 April 1902, C. Scottsberg (S!).
Lecidea protracta Darb., Wiss. Ergebn. Schwdeisch. Südpolarexpedit. 1901–1903. 4: 4 (1912).—Lecidella protracta (Darb.) Hertel Beih. Nova Hedwigia 79: 450 (1984); type: Falkland Islands, [no date or locality], C. Scottsberg (S!).
Remarks. When Hertel (Reference Hertel1984) transferred Lecidea protracta to Lecidella, he commented that it was very close to the Lecanora marginata group and that better developed material was required. Later (Hertel 1992), he annotated the type species “Lecanora protracta”, although he never published that combination. Based on examination of the specimens in MSC, one of us (AMF) had previously expressed doubts as to whether Lecanora capistrata (Darb.) Zahlbr. and Lecidella protracta (Darb.) Hertel were distinct species (Fryday Reference Fryday2004). Further investigation, including examination of type material, has shown that L. protracta apparently differs from Lecanora xantholeuca only in having pruinose apothecia that react Pd+ orange in section (Hertel Reference Hertel1984; Knoph & Leuckert Reference Knoph and Leuckert1994). As the type specimen of L. protracta has mostly non-pruinose apothecia, we consider this to be insufficient grounds to recognize L. protracta as a distinct species, and include it as a synonym of Lecanora xantholeuca.
Lecanora xantholeuca is similar to L. capistrata but typically has a smooth, continuous-rimose, clear yellow thallus, apothecia with a persistent, raised proper margin with a much better developed exciple, and shorter, bacilliform conidia 10–15(–18) µm long [flexuose, (25–)30–35(–50) µm long in L capistrata].
Lecanora xantholeuca is known only from the Falkland Islands where it grows on siliceous rock outcrops from coastal cliffs to mountain summits.
Selected specimens seen (all MSC). Falkland Islands (all collected by H. A. Imshaug & R. C. Harris unless otherwise noted): East Falklands (Isla Gran Malvina): sinum Port William, Stanley, ix 1850, W. Lechler (G—lectotype; Plantae Insularum Maclovianae #56); Stanley, UTM Grid 21F VC 3871, outcrop on Sapper Hill, 135 m alt., 1968, Imshaug 39793; Mt. Usborne, UTM Grid 21F UC 7371, feldmark on leeward side of Mt. Usborne 1 summit, c. 700 m alt., 1968, Imshaug 39919; Darwin Settlement, UTM Grid 21F UC 6457, coastal cliffs on S side of Carcass Bay, Darwin Harbour, 1968, Imshaug 40234; Port William, UTM Grid 21F VC 4373, outcrop on Engineer Point headland, The Narrows, c. 15 m alt., 1968, Imshaug 40633. West Falklands (Isla Soledad): Hill Cove, UTM Grid 21F TC 8390, cliffs along sea at point Settlement, 1968, Imshaug 41277.
Lepraria malouina Øvstedal sp. nov.
MycoBank No.: MB 564658
Thallus leprosus, acidae usnicum et sticticum continens.
Typus: Falkland Islands, West Falkland, Weddell Island, summit of Circum Peak, UTM 21F TC 3039 [−51·927500°–60·923500°], 650 ft. [198 m], 6 January 1968, H. A. Imshaug (42023) & R. C. Harris (MSC-0108539—holotypus).
(Fig. 5B)
Thallus entirely leprose, pale yellow-grey, 5–6 cm wide, cracked. Prothallus thin and scarcely visible, pale. Hypothallus thick, 0·6–0·8 mm high, pale, loosely organized, with the lowermost part brown to dark brown where the hyphae attach to the substratum. Hyphae hyaline, c. 2 µm diam., ±smooth, septate, often branched at septa. No marginal lip. Rhizohypahe absent. Granules 35–40 µm diam., no pseudocortex formed, with ±short, protruding hyphae.
Chemistry. Usnic acid (major), stictic acid complex (major).
Etymology. Derived from the French name for the islands, Îles Malouines, named after the fishermen and mariners of St. Malo (France) who were the first to settle here.
Distribution and ecology. Known only from rock on the Falkland Islands.
Comments. The terminology of Lendemer (Reference Lendemer2011) is used. In South America, 30 species of Lepraria are currently recognized (Flakus & Kukwa Reference Flakus and Kukwa2007; Lendemer Reference Lendemer2010; Elix et al. Reference Elix, Spielmann and Øvstedal2010; Flakus et al. Reference Flakus, Elix, Rodriguez and Kukwa2011), none of which have the chemical content encountered in the present species. Lepraria species with usnic acid, Lecanora ecorticata J. R. Laundon [syn. Lepraria ecorticata (J. R. Laundon) Kukwa], Lepraria coriensis (Hue) Sipman and L. usnica Sipman, belong to other genera, and do not form a monophyletic clade (Nelsen et al. Reference Nelsen, Lumbsch, Lücking and Elix2008).
Additional specimens examined. Falkland Islands: West Falkland: West Point Island, steep slope and cliffs facing the Woolly Gut, UTM 21F TD 4403-4404 [−51·355667°–60·670333°], Hebe-shrub, 1968, H. A. Imshaug (40895) & R. C. Harris (MSC); ibid., near The Waterfall, 21F TD 4302 [−51·368000°–60·685333°], 100–300 ft. [30–91 m], Hebe-shrub, 1968, H. A. Imshaug (40691, 40701) & R. C. Harris (MSC); ibid., summit of Mt. Misery, UTM 21F TD 4201 [−51·374833°–60·703333°], 1100 ft. [335 m], polsterboden (but on rock), 1968, H. A. Imshaug (40675) & R. C. Harris (MSC).
Rhizocarpon simillimum (Anzi) Lettau
This is a microscopically distinctive species because of its small (12–16×6–8 μm), 1-septate, pigmented ascospores, K+ purple epihymenium and exciple, and amyloid medulla. It is reported here new to the Southern Hemisphere from several collections on siliceous rocks from the Falkland Islands, from coastal to alpine habitats. It is also reported from one inland locality on South Island, New Zealand.
The thallus of Northern Hemisphere collections is reported to contain either stictic acid or no substances (Timdal & Holtan-Hartwig Reference Timdal and Holtan-Hartwig1988) and the collections reported here also mostly lack lichen substances. However, two populations from the Falkland Islands (Imshaug 41482, 41485 & 42109, see below) have a thallus containing gyrophoric acid. Nevertheless, as they are otherwise identical to collections lacking lichen substances, they are included in R. simillimum.
Specimens seen (all MSC). Falkland Islands: East Falkland: Mt. Usborne, side of valley SW of Mt. Usborne, UTM 21F UC 7068 [−51·720000°–58·869833°], 200 ft. [61 m], large shale outcrop, 1968, Imshaug (40209) & Harris; Port William, The Narrows, Engineer Point, UTM 21F VC 4373 [−51·683833°–57·826333°], 50 ft. [15 m], outcrops on headland, 1968, Imshaug (40639) & Harris; ibid., north of Hell's Kitchen, UTM 21F VC 4678 [−51·638667°–57·777167°], 100 ft. [30 m], peat bog, 1968, Imshaug (41627) & Harris; Stanley, Mullet Creek, UTM 21F VC 3270, [−51·716167°–57·976167°], 100 ft. [30 m], stream below fiord, 1968, Imshaug (41482, 41485) & Harris. West Falkland: West Point Island, summit of Mt. Misery, UTM 21F TD 4201 [−51·374833°–60·703333°], 1100 ft. [335 m], polsterboden, 1968, Imshaug (40676) & Harris; Fox Bay, E of East Head, along N slope of coast ridge, UTM 21F TC 9435 [−51·994833°–59·996500°], 100–200 ft. [30–61 m], Empetrum-heath, 1968, Imshaug (42109) & Harris; ibid., NW side of Weasels Bay, UTM 21F TC 9038 [−51·960833°–60·053333°], small sea cliffs near beach, 1968, Imshaug (42238) & Harris.—New Zealand: South Island: Mt Cook National Park, Hooker Valley, near front of Hooker Glacier, north of Stocker Stream, c. 3000 ft [914 m]., in heath-scrub, 1970, Imshaug 47470 (MSC).
Rimularia andreaeicola Fryday sp. nov.
MycoBank No.: MB 564659
Ab omnibus speciebus generis Rimulariae habito bryicola, thallo brunneo granulato et lichenalibus substantilis absentis differt.
Typus: Falkland Islands, East Falkland, Mt. Usborne, Table Rock, UTM 21F UC 7868 [−51·719500°–58·766000°], 1800 ft. [549 m], feldmark outcrops on summit, 9 January 1968, H. A. Imshaug (40082-B) & R. C. Harris (MSC-0108540—holotypus; BCRU—isotypus).
(Fig. 6A)
Fig. 6. A, Rimularia andreaeicola Fryday (Imshaug 40082-B—holotype); B, Rimularia subpsephota Fryday (Imshaug 42143—holotype). Scales: A=0·5 mm; B=1·0 mm. In colour online.
Thallus of ±dispersed brown, often grey pruinose, bullate areoles (0·13–)0·15–0·20 mm across; growing over Andreaea sp. Cortex not clearly defined but cortical cells brown, 5 µm across. Medulla I−. Photobiont chlorococcoid, cells 8–12(–15) µm.
Apothecia black, lecideine, orbicular, occasionally somewhat angular, flat 0·5–0·7 mm diam., proper exciple thick (0·5 mm), raised and persistent. Hymenium hyaline, I+ blue, 130–140 µm tall; epihymenium 10–15 µm thick, pale brownish. Paraphysoids 1·0–1·5 µm thick, septate and moniliform, richly branched and anastomosing, apices swollen to 4 µm with dark cap. Asci c. 55–60×20–30 µm, broadly cylindrical to sub-clavate, Rimularia-type. Ascospores hyaline, simple, 8 per ascus, 15–18(–21)×10–12 µm, thick-walled (c. 1 µm thick). Hypothecium pale to mid brown merging into the exciple. Excipulum dark brown, cupular, 100 µm wide.
Conidiomata not seen.
Chemistry. C−, K−, KC−, Pd−. No substances detected by TLC, but material very scanty.
Comments. The collection from Mt. Maria (West Falkland) differs in that the thalline granules are creamy white rather than brown. However, as all other characters agree with R. andreaeicola, and the specimen is extremely small, it is included in R. andreaeicola pending the availability of better developed material.
The only other bryophilous species of Rimularia are the Northern Hemisphere R. sphacelata (Th. Fr.) Hertel & Rambold, which has a thallus containing norstictic acid, and the Australasian R. hepaticola Kantvilas, which contains porphyrilic acid. In addition, neither of these species, nor any other species of the genus known to us, has a thallus consisting of dispersed, brown, bullate areoles. Associated species include Bartlettiella fragilis, Pertusaria spegazzinii, Poeltidea perusta and Schaereria porpidioides on the Falkland Islands, and Endocena informis on Tierra del Fuego.
Additional specimen examined. Chile: Magallanes and Antártica Chilena Region: Isla Navarino, way Cerro Bandera to Laguna El Salto, 54°58′17·3″S, 067°67′59·0″W, 600–800 m, siliceous boulders, 2005, J. Etayo (22432), L. García & A. Gómez-Bolea (hb. Etayo).—Falkland Islands: East Falkland: Mt. Usborne, Table Rock, UTM 21F UC 7868 [−51·719500°–58·766000°], 1800 ft. [549 m], feldmark outcrops on summit, 1968, Imshaug (40125-B) & Harris (MSC). West Falkland: Port Howard, east slope of Mt. Maria UTM 21F UC 2179 [−51·601833°–59·585000°], 1800 ft. [549 m], 1968, Imshaug (41397) & Harris (MSC).
Rimularia subpsephota Fryday sp. nov.
MycoBank No.: MB 564660
Rimulariae psephotae similis sed thallo albido, uno centimetro diametro, et acidum norsticticum absenti.
Typus: Falkland Islands, West Falkland, Fox Bay, N of East Head, UTM 21F TC 9435 [−51·992667°–60·000833°], along shore, 7 February 1968, H. A. Imshaug (42143) & R. C. Harris (MSC-0136487—holotypus; BCRU—isotypus).
(Fig. 6B)
Thallus white to pale grey, composed of thick convex areoles (0·3–0·5 mm) usually in small (to 1 cm diam.) patches, but effuse and with thinner thallus with a black fimbriate prothallus when growing on quartzite. Cortex not clearly defined but with a thin (3 µm) pale brown layer immediately above the photobiont layer and a hyaline epinecral layer (10–50 µm) that is I+ violet. Medulla with numerous fine granules (not dissolving in K or N), I+ violet. Photobiont chlorococcoid, cells 8–12(–15) µm.
Apothecia black, lecideine, rounded to angular, occasionally lirellate with slit-like disc, flat 0·4–0·6 mm diam., proper exciple thick (0·5 mm), raised and persistent. Hymenium hyaline, I+ blue, 80–100 µm tall; epihymenium 10–15 µm thick, brownish grey (K+ violet-brown; Sedifolia-grey). Paraphysoids 1·5–2·0 µm thick, septate and moniliform, richly branched and anastomosing, apices swollen to 5 µm with dark cap. Asci c. 50×15–20 µm, broadly cylindrical to sub-clavate, Rimularia-type; ascospores hyaline, simple, 8 per ascus, 13–15×9–10 µm, thick-walled (c. 1 µm thick). Hypothecium hyaline above (subhymenium) of randomly arranged swollen hyphae, pale to mid brown merging into the exciple. Excipulum dark brown, cupular, 50–70 µm wide, of dark-walled, elongated cells 10–15×3–5 µm.
Conidiomata not seen.
Chemistry. C−, K−, KC−, Pd−. No substances by TLC.
Comments. Collections of this species have previously been identified as R. psephota (Tuck.) Hertel & Rambold. However, although that species also has an epihymenium containing sedifolia-grey (K+ violet) and a thallus with an amyloid medulla (I+ violet), it also has a more widespreading, darker grey thallus containing norstictic acid. All collections of R. subpsephota were made from maritime rocks, or at least rocks close to the sea.
Additional specimens examined (all MSC except where noted). Argentina (all collected by H. A. Imshaug & K. E. Ohlsson): [Tierra del Fuego: Depto Ushuaia,] Bahia Primera, Cabo Kendall peninsula, 54°49′S, 64°07′W, littoral zone, 1971, Imshaug 52320; Cabo San Bartolome, N side of peninsula, 54°54′S, 64°42′W, littoral zone, 1971, Imshaug 53186.—Falkland Islands (all collected by H. A. Imshaug & R. C. Harris except where noted): East Falkland: sinum Port William, ix 1850, W. Lechler [B! (4421; lectotype of Lecanora atroviolacea); Plantae Insularum Maclovianae #60]; Port William, N shore of Cape Pembroke, peninsula S of Kelly Rocks, UTM 21F VC 4674 [−51·680167°–57·774667°], 1968, Imshaug 39836. West Falkland: West Point Island, along NE shore adjacent to Cape Terrible, 21F TD 4006 [−51·327833°–60·726500°], coastal rocks, 1968, Imshaug 40776, 40778; ibid., Devils Nose, 21F TD 4104 [−51·350667°–60·714833°], 50 ft. [15 m], sea cliffs, 1968, Imshaug 40855; Hill Cove, Point Settlement, UTM 21F TC 8390 [−51·496333°–60·116833°], cliffs along sea, 1968, Imshaug 41260; Weddell Island, along E side of Ottos Bay, 21F TC 3243 [−51·895000°–60·896667°], coastal rocks, 1968, Imshaug 42037.—South Georgia: Royal Bay, above Köppen Point, GR 162 098 (sic.) [?-54·5075°–36·0100°], 30 m, on dry, south-facing bird perching stone, 1972, D. C. Lindsay 4092 (M, sub Tephromela atrocaesia).
Usnea austrocampestris Øvstedal sp. nov.
MycoBank No.: MB 564661
Usneae aurantiaco-atrae similis, sed axis tenuis (19–43%) et habitus terricola.
Typus: Falkland Islands, West Falklands, Port Howard, summit ridge of Mt. Maria, UTM UC 2078-2079 [−51·608833°–59·595667°], 2000–2150 ft. [610–655 m], feldmark and outcrops, 28 January 1968, H. A. Imshaug (41396) & R. C. Harris (MSC-0108542—holotypus).
(Fig. 5C)
Thallus fruticose, yellow-green, straggling on ground, with no holdfast, up to 22 cm long, anisotomically branched, main branch not clearly distinguished, thickest branches to 0·8 mm diam., papillate, annulated towards ends. In section, the central axis varies from 19–43% of total branch diameter.
Apothecia in central part of thallus, lateral, on larger branches only, flat, up to 7 mm diam.; disc dark brown to black, thalline margin very thin, to 0·1 mm broad. Exciple on outside with low ridges and papillae, no rays present.
Chemistry. Usnic, salazinic, norstictic acids by TLC.
Distribution and ecology. Straggling on soil on mountain tops in West Falkland. Endemic.
Comments. This taxon keys out as U. aurantiaco-atra (Jacq.) Bory in Walker (Reference Walker1985), but differs from that species in at least two characters: the central axis, which in U. aurantiaco-atra (on Falkland Islands) is 53–95% of total diam., and the ecology (always with a distinct holdfast on rock in U. aurantiaco-atra).
The ‘Neuropogon-group’ of Usnea, although easily recognizable, has been regarded at different taxonomic levels, from genus level to no value at all (see discussion in Wirtz et al. Reference Wirtz, Printzen, Sancho and Lumbsch2006 and Lumbsch & Wirtz Reference Lumbsch and Wirtz2011). In the most recent monograph, Walker (1985) recognized 15 species, but later molecular studies (Wirtz et al. Reference Wirtz, Printzen, Sancho and Lumbsch2006; Seymour et al. Reference Seymour, Crittenden, Wirtz, Øvstedal, Dyer and Lumbsch2007; Lumbsch et al. Reference Lumbsch, Ahti, Altermann, Amo De Paz, Aptroot, Arup, Bárcenas Peña, Bawingan, Benatti and Betancourt2011; Lumbsch & Wirtz Reference Lumbsch and Wirtz2011) have revealed that there are more species present. The phylogenetic relationships within this group have recently been investigated by Lumbsch & Wirtz (Reference Lumbsch and Wirtz2011), who found that U. aurantiaco-atra is nested with U. acromelana.
Motyka (Reference Motyka2011936) treated the U. aurantiaco-atra complex and found 5 species, mainly based on minor morphological and anatomical characters. Lamb (Reference Lamb1939) treated the same complex, and recognized 4 species, but later (1964) modified it to two. The two taxa were divided on chemical content: U. aurantiaco-atra with usnic acid only or usnic and fumarprotocetraic acids, whereas U. melaxantha contained usnic, salazinic and norstictic acids. Walker (Reference Walker1985) regarded these as subspecies of U. aurantiaco-atra. Lamb (Reference Lamb1939, Reference Lamb1964), who collected on the Falkland Islands, does not mention any straggling specimens, while Walker (Reference Walker1985), writes; “Thalli may rarely become subdecumbent or straggling and then may be sparsely pigmented, sterile and infrequently to richly branched…”, but this is her only mention of straggling specimens. It seems that only Imshaug and Harris have collected from these populations on the summits of the West Falkland mountains. However, Engel (Reference Engel1990), who divided the vegetation of the Falkland Islands into c. 10 units, found that the Mesic Feldmark was “characterized by a rather conspicuous fruticose lichen flora (principally Neuropogon)”. This is a vegetation type found almost exclusively on the mountain tops, such as Mt. Usborne 1 (alt. 700 m). Also, a small number of liverworts were found exclusively in such vegetation (Engel Reference Engel1990). Among the vascular flora, three species are confined to upland localities, viz. Azorella selago, Acaena microcephala and A. pumila (Moore Reference Moore1968), all species that are widespread in southernmost South America, but not restricted to upland areas there.
Additional specimens examined. Falkland Islands: West Falkland: Mt. Adam, summit ridge, 2200–2297 ft. [671–700 m], feldmark, 1968, H. A. Imshaug (41038, 41072) & R. C. Harris; Port Howard, summit of Mt. Maria, 2158 ft. [658 m], feldmark, 1968, H. A. Imshaug (41319) & R. C. Harris.
We gratefully acknowledge support from the US National Science Foundation, Award No. DBI–9808 735 (A. Prather, PI) to Michigan State University, that facilitated access to Dr Imshaug's collections, and Dr H. Peat, the curator of AAS, for the loan of specimens in her care. We also thank the curators of B, FH, G, M and S for the loan of collections in their care. We thank J. Berge & B. Helle, Bergen, for help with illustrations, Professor P. M. Jørgensen, Bergen, for correction of Latin diagnoses, and Professor J. A. Elix, Canberra, for chemical analyses.
