Revista Chilena de Historia Natural 56: 123-136, 1983 The Flora of the Fuego-Patagonian Cordilleras: its Origins and Affinities*

Flora de las cordilleras de Tierra del Fuego y de la Patagonia: sus origenes y afinidades

DAVID M. MOORE

Department of Botany, Science Laboratories, The University, Whiteknights, Reading, RG6 2AS, England

ABSTRACT

The cordilleras of Tierra del Fuego and southern Patagonia contain floristic elements which reflect both their histories and present conditions. The mountains to the west and south of the zone, repre- senting the southernmost extension of the , are the wettest and highest of the region and their species show some Antarctic affinities. The other Fuego-Patagonian mountains are lower and drier, with their demonstrating many affinities with lowland Patagonia and the eastern Andes and pre- cordilleras further north. Nevertheless, the large number of orophytic species which occur at lower elevations testifies to the youth of the southern montane floras, which have moved upwards during the 16,000 years since the last glaciation. The endemic SPecies and genera in these zones indicate that they have immigrated to these areas from the south, from the east and from the north. Key words: Floras, Fuego-Patagonia, orophytic species, post-glacial.

RESUMEN

Las cordilleras de la Tierra del Fuego y de la Patagonia austral comprenden elementos que reflejan sus historias y, tam bién, las condiciones actuales. Las sierras a1 oeste y a1 sur de esta zona, que representan el extremo más austral de la Cordillera de los Andes, son las más humedas y las más altas de la region y sus especies ostentan afinidades antárticas. Las otras sierras fueguino-patag6nicas son más bajas y secas, y sus plantas muestran relaciones con las floras de la meseta patag6nica y con la precordillera más a1 norte. Sin embargo, el gran numero de especies orofiticas que crecen en elevaciones más bajas demues- tra la juventud de la flora de todas las cordilleras del sur que han migrado hacia arriba durante los 16.000 aiios despues de la ultima glaciaci6n. Las especies y generos presentes en estas zonas indican que elias inmigraron desde el sur, el este y el norte. Palabras claves: Floras, Tierra del Fuego, Patagonia, especies orofiticas, post-glacial.

INTRODUCTION lower ground south of 44° S lat., at least west of the Andes (Briiggen 1950, Vui- Although the origin of the Cordillera llemier 1971 ). Such cover was intermit- de los Andes and its attendant moun- tent, since the glaciers advanced and re- tain ranges may be traced back some treated four times; the most recent retreat, 100 million years to the Cretaceous period, in the aftermath of which we now live, they did not attain their present altitude began about 16,000 years ago. However, until the Upper Pliocene, about 2 million the persisting glaciers in Fuegia (Cordillera years ago (Briiggen 1950, Harrington Darwin and Isla Santa Inés, for example) 1956). Subsequent to that the southern and the extensive icefields of the Hielo cordilleras, our concern here, were subject- Patagónico Sur serve as a reminder that the ed to the Pleistocene glaciations which glacial retreat is still not complete in these covered all the mountains and much of the regions.

* Paper presented in the Symposium "Biogeography and Evolution of the Andean Flora" held during the IV Meeting of the Botany Section, Sociedad de Biologia de , 7-10 September, 1982, Antumapu, Santiago.

(Received 24 May 1983. Accepted 2S September 1983). 124 MOORE

The southernmost parts of the Andes, the influence of the Hielo Patag6nico which attain maximum altitudes of about Sur and the glaciers to which it gives rise. 3300 m in southern Patagonia and about To the west of the cordillera, on the islands 2500 m in Tierra del Fuego, constitute of the west Patagonian channels, the tree- a barrier to the moisture-laden winds line becomes increasingly lower and ill- which prevailingly blow from the south defined under the effects of the exposed, and west. As a result of this there is very oceanic conditions so that towards the much more precipitation to the west and outer parts of the Chilean archipelago south of these mountains, while the lower trees are largely confined to well-drained ranges lying in the rain shadow to the east coastal sites and sheltered valleys. The of the main cordillera in Patagonia and drier mountains of the 'Marginal Cordi- to the north in Tierra del Fuego are much llera' along the Argentinian-Chilean frontier drier. to the east of Ultima Esperanza have a In addition to the differences, already tree-line at about 600-800 m in their noted, in altitude and precipitation be- southern part (e.g. Sierra Dorotea, Sie- tween the Andes and the ranges of the rra del Cazador). However, further north, Marginal Cordilleras (Kranck 1932) in in the region of the Sierra Baguales-Sierra their rain shadow, there are also geologi- Vizcachas, there are no forests and the cal differences of importance to the plant- transition to an orophytic zone is marked life. The main mass of the southern Andes by less obvious changes in the structure is composed of strongly deformed and met- and floristic composition of the vegeta- amorphosed Palaeozoic to Jurassic mica- tion. and quartz-schists, penetrated in many places by lower Tertiary granites and grano- THE VEGETATION diorites, and flanked by dark slates (grey- wackies), marls and quartz-porphyries. The orophytic zones of Fuego-Patagonia, West and south of these the Jurassic-Low- as circumscribed above, contain a rela- er Cretaceous igneous greenstooes and tively small number of vegetation-types; the Jurassic 'Andean diorites' form the however, they intergrade so frequently Fuegian and western Patagonian archipel- that it is often difficult to obtain a clear agos. All these rocks· weather rather slow- picture, particularly in view of the nume- ly to give only skeletal lithosols initially. rous local variants. Nevertheless, by consi- In contrast, the 'Marginal Cordilleras' derable simplification, 6 principal structur- are largely composed of Cretaceous sedi- al types of community can be seen to ments -sandstones, clay-slates, marls and form the basis of the montane vegetation conglomerates- which are strongly folded, in these austral regions -cushion heath, with the beds often vertical. These softer grass/cushion heath, dwarf-shrub heath-, rocks erode to give deeper, clayey soils, montane meadows and two quite different which are very subject to solifluction at kinds of feldmark or 'desierto andino', higher elevations. depending upon the substrate. Although not entirely satisfactory, the delimitation of an orophytic flora and Cushion Heath. Throughout much of vegetation in most Fuego-Patagonian Tierra del Fuego, except the southern mountains can be achieved by basing it and western parts of the archipelago, on the upper limit of the forests (Moore and in the southern parts of the 'Mar- 1975). The timberline, usually comprising ginal Cordillera' in Patagonia, a cushion a dense belt of 'Krumholz' formed by heath dominated by Bola:x gummifera Nothofagus, commonly, but by no means is common at, and extending some dis- always. N. , lies at an average tance above, timberline. Since this formation altitude of about 550-600 m in Tierra del is rather frequent at lower elevations, it Fuego, though it may be lower on the is not surprising to find that it contains smaller drier sierras and higher {up to many widespread species, both cushion- 700 m) on the larger mountain masses. forming (e.g. Abrotanella emarginata, Azo- North of the Estrecho de Magallanes the rella lycopodioides, Colobanthus subulatus situation is somewhat more varied. Along and Drapetes muscosus) and not (e.g. the flanks of the Cordillera de los Andes Acaena magellanica, rubrum, the tree-line lies at about 640-750 m, Festuca contracta, Luzula alopecurus, Ly- though it may be greatly depressed under copodium magellanicum and Pernettya FLORA OF FUEGO-PATAGONIAN CORDILLERAS 125 pumila). This community provides a ha- in which Empetrum rubrum and, to a lesser bitat for the endemic Tetrachondra pata- extent, Pernettya pumila, are important gonica ssp. fueguina and Onuris alismatifo- occur widely in the orophytic zone, espe- lia in Tierra del Fuego, while such rela- cially where the soils are relatively shallow tively restricted Fuego-Patagonian species as and well-drained with adequate available Saxifragodes albowiana and Acaena te- moisture. Such communities intergrade nera are also largely confined to it. in a complex fashion with the various facies of the cushion heaths referred to Grass/Cushion Heath. In the northern earlier and with the true feldmark to be parts of the South Patagonian 'Marginal mentioned next. In the higher rainfall Cordillera, the Sierra Baguales-Sierra zone of the Cordillera de los Andes and on Vizcachas region, where there is no forest, the mountains of the canales and archi- the lowest orophytic vegetation consti- pelago further to the west, various commu- tutes a grass/cushion heath. In this, Festuca nities of the dwarf-shrub heath occur im- gracillima, which dominates the grassland mediately above the timberline and, prevalent at lower altitudes, is associated indeed, where this is ill-defined or non- with Bolax gummifera. Such communi- existent, grade into the non-montane ties also replace the cushion heath above vegetation in which Empetrum rubrum timberline in several areas further south is also frequently important (Moore in the 'Marginal Cordillera', as on Cerro 1979). The dwarf-shrub heath is probably Solitario and Cerro Castillo, and also further richer in species and includes more com- west on the mountains of Peninsula Anto- munities than any other physiognomic nio Varas. Amongst the most common vegetation-type present in the montane and conspicuous of the communities in- zones of the Fuego-Patagonian mountains. cluded in the grass/ cushion heath may It is, of course, impossible to detail here be noted Acaena magellanica, A. pinna- all this variation, but some examples should tifida, Azorella fuegiana, A. lycopodioides, suffice. Whilst the cushion-heath, dominated Co/obanthus subu/atus, Draba magel/anica, by Bolax gummifera, already described, Erigeron myosotis, Hypochoeris incana, intergrades with the dwarf-shrub heath, Luzula alopecurus, Nassauvia abbreviata, an important facet in which Adesmia Perezia recurvata and Thlaspi magel/ani- salicornioides is a co-dominant should cum. be mentioned here. Furthermore, commu- nities in which Empetrum rubrum is Dry Feldmark (Desierto Andino). In associated with such taxa as Leucheria the 'Marginal Cordilleras' of Fuego-Pata- hahnii, Nassauvia juniperina and Berberis gonia both the cushion heath and the empetrifolia occur rather commonly north grass/cushion heath, already referred to, of the Estrecho de Magallanes. can give way to deep, open, sparsely vegetated soils, especially on steep slopes. These areas are perhaps most aptly termed Feldmark. On the wetter mountains Desierto Andino (Pisano 1974), but of the Central Cordillera of Tierra del their very sparse vegetation is structurally Fuego and of the Cordillera de los Andes similar to a typically drier type of feld- in southern Patagonia, as well as on the mark (Moore 1975). A few species of the higher summits of the archipelagos further open facies of the cushion and grass/ to the south and west, the uppermost cushion heath, such as Calandrinia caes- vegetation constitutes a true feldmark, pitosa, Hamadryas delfinii, Luzula chi- with frequent evidence of frost polygons lensis, enneaphylla, Nassauvia pyg- and other periglacial phenomena. Here, maea, Senecio al/oeophyllus and S. mage- the extensive areas of open rock fragments llanicus are able to withstand the rather or exposed mineral soil support a sparse unstable soil conditions of this vegetation- vegetation in which several species of type, which provides the principal habitat the more open facies of the dwarf-shrub for such species as Menonvillea nordensk- and cushion heaths figure, such as Abro- joldii, Perezia megalantha, Phaiophleps tanella emarginata, Acaena magellanica, biflora ssp. lyckholmi, Tristagma ameghi- Colobanthus subulatus, Hypochoeris inca- noi and T. nivalis. na, Luzula alopecurus, Nassauvia pyg- maea and Polystichum andinum. These Dwarf-Shrub Heath. In most of the areas also provide the principal or sole Fuego-Patagonian mountains, communities habitats for such species as Moschopsis 126 MOORE rosulata, Nassauvia lagascae, the Fuegian nes are considered separately, even though endemic Nassauvia latissima, Saxifragella the former area has only 2/3 of the total bicuspidata and Valeriana magellanica. flora of the latter. This reflects the compa- Lichens, such as Usnea spp., form dense rable conditions and age of the Fuego- communities on the rocks in the feldmark. Patagonian mountains when compared with, for example, the more oceanic and Alpine 'meadow'. Where streams or species-poor (Islas Malvi- seepage areas, derived in many cases from nas), where the wider ecological ampli- the glaciers or slow-melting snow patches, tude of the species results in about 38% of occur in montane areas a rather distinctive the total flora occurring in the montane and often quite rich, vegetation is found zones (Moore 1968), most of them also to which the rather misleading term 'mea- growing at lower altitudes. dow' has been applied. Wet areas in which there is some development of soil or peat Distribution of the montane flora frequently support mats or hummocks of such species as Abrotanella linearifolia, Table I list all the species of the Fuego- A. trichoachaenia, appendiculata, Patagonian cordilleras known with certainty C. dioneifolia and Plantago barbata, on and to occur in the orophytic zones as defined amongst which grow, for example, Acaena earlier in this account. Whilst there are antarctica, Caltha sagittata, Hierochloe re- certainly omissions and inaccuracies of do/ens, Lagenifera nudicaulis, Ourisia detail in the list, it shows clearly that breviflora, Oxalis magellanica, Primula ma- over 80% of the species also occur at gellanica, Tapeinia obscura and Viola lower altitudes in the region; only 42 spe- commersonii. Where the substrate is of cies (marked with full stars in Table I), coarse gravel or rocky, Cardamine glacia- or about 18% of the total, seem to be lis, Epilobium nivale, Eudema hauthalii, restricted to the montane areas. Hamadryas magellanica, Viola tridentata Dealing first with the species occurring and others become prominent. Bryophytes in both lowland and higher elevation ha- are common in these sites and in the wetter bitats it can be seerl that they fall into 3 mountains of the western archipelago more or less well-defined categories. The form substantial 'banks' or cushions first and much the smallest group of spe- which provide a habitat for a few of the cies comprises those which occur more above species, most notably Tapeinia or less ubiquitously in the Fuego-Patago- obscura and Viola commersonii. Moist, nian mountains -Acaena magellanica, sheltered more or less level sites can often Empetrum rubra, Festuca pyrogea, Pere- support a graminoid vegetation in which zia pilifera and Phleum alpinum- thus species such as Carex magellanica, Carpha stressing the wide variety of montane alpina, Cortaderia pilosa, Juncus scheuch- conditions which few species have the zerioides, Orthachne rariflora, Rostkovia capacity to cope with. This is further magellanica, Schoenus andinus and Unci- emphasised by the remaining two groups na kingii are variously present to give a of species which occur either on the drier, sward having many of the characteristics eastern Marginal Cordillera or on the main of lowland bogs, particularly those in the cordillera and westwards in southern south and west of the region. Patagonia. Twenty four species occur in montane THE FLORA habitats only on the wetter, central and western Patagonian cordilleras. Most of As far as we know at present the native these have a generally western and southern vascular flora of southernmost South distribution in lowland Fuego-Patagonia America, from about 51º S lat. south- -Bolax caespitosa, Caltha dioneifolia, Do- wards to the archipelago of Cabo de Her- natia fascicularis, Gaimardia australis, Ly- nos, totals some 6 50 species (Boelcke copodium alboffii, L. confertum, Oreo- et al, unpub., Moore 1974, 1983). Of bolus obtusangulus, Orthachne rariflora, these, about 28% occur in the orophytic Phyllachne uliginosa, Senecio kingii, Tribe- habitats referred to earlier. Interestingly, les australis, Uncinia kingii, Viola commer- this percentage is exactly the same when sonii, and V. tridentata, while almost Tierra del Fuego and southernmost Pa- all the others have a wider range but only tagonia north of the Estrecho de Magalia- in moist habitats -Drapetes muscosus, FLORA OF FUEGO-PATAGONIAN CORDILLERAS 127

Marsippospermum grandiflorum, Perezia lac- 40 species (c. 18%) are restricted to mon- tucoides, Pernettya pumila, Rostkovia tane habitats though a few, such as Ades- magellanica, Senecio acanthifolius and mia salicornioides and Phaiophleps biflora Serpyllopsis caespitosa. The three remain- ssp. lyckholmi, occasionally occur at lower ing species in this group -Esca/lonia se- altitudes in Tierra del Fuego. More than rrata, Grammitis mage/lanica and Notho- half (27) the species occur only in the fagus antarctica- serve to emphasise the Marginal Cordillera of southern Patagonia poor development of a distinct orophytic while the 12 of these species that reach flora in the severe environmental condi- Fuegia are generally present only in the tions of the area west of the Cordillera de northern mountains or the drier parts los Andes, conditions also reflected in the of the Central Cordillera along the Canal impoverished flora of this region as indi- Beagle, though Saxifragella bicuspidata is cated in Table I. a conspicuous exception being widespread Much the largest group of species, to- on the wetter Fuegian mountains as well. talling 115, of those present both in The majority of the species belong to montane and lowland areas, is that in genera such as Benthamiella, Eudema, which the mountain occurrences are only Menonvillea, Moschopsis, Onuris, Tristagma on the drier marginal cordilleras. As might and Xerodraba that are well diversified be expected, virtually all these species in the drier parts of the Cordillera de los are present in the Patagonian Lowlands Andes and adjacent ranges further north, eastwards from the cordilleras to the while others are in more widely distributed Atlantic coast. The comparative floristic but essentially Andean genera (e.g. Nas- richness of the marginal cordilleras under- sauvia, Perezia). On the other hand, the lines their generally more favourable en- species of Adesmia, Astragalus, Phaio- vironmental conditions, with protection phleps, Senecio and Silene have obvious from the westerly tempests prevalent in links with lowland members of their those latitudes and their generally deeper, genera. better developed soils which are more Only 6 orophytic species are restricted conducive to plant growth than the rather to the wetter main or central cordilleras skeletal soils at high elevations on the of Fuego-Patagonia. This reflects the western mountains. A contributory factor relative impoverishment of the floras of is also the large pool of species in the these mountains referred to earlier. There adjacent lowlands and this seems to be is another parallel in that although five of supported by the differences, shown in the six genera involved have a strong Table I, between the southern and more 'Andean' base, there is a definite circum- northerly parts of the marginal cordille- Antarctic tendency as shown by Azorella ras. The northern mountains (Sierra Ba- selago, present on several guales, Sierra Vizcachas), which lack islands, and Ourisia breviflora, member forest at lower elevations, have a much of a genus which is well-developed in New richer orophytic flora than those further Zealand as well as in southern South south which are forested. It is at least America. Furthermore, the closest relative arguable that the gradual transition from of Tapeinia obscura is the only other lowland steppe to montane habitats per- member of the genus, T. pumila, which mits a much easier migration of suitable is prominent in the lowland communities plants to higher altitudes than is the case of the southern and western parts of the when a forest barrier has to be traversed. Fuego-Patagonian archipelago. The species distributions in the Fuegian The 7 orophytic endemics of Tierra del mountains generally mirror those just Fuego reflect the relationships referred described, though the floristic dissimila- to above. As Moore (1975) has discussed, rity between the northern marginal and Nassauvia latissima illustrates the central more southerly Central Cordilleras is not Andean connection, Onuris alismatifolia so great (Moore 1975). This undoubtedly the affinities with the drier eastern cordi- reflects the reduced environmental diffe- lleras further north, Polystichum andinum rences between the systems and also the those with lowland Fuego-Patagonia, Tetra- much smaller pool of potential immi- chonda patagonica ssp. fuegiana belongs grants in lowland Fuegia. to a sub-andean species but has many Strictly montane species. Out of the total features of the New Zealand T. hamil- orophytic flora of Fuego-Patagonia only tonii Petrie. This circum-Antarctic tenden- 128 MOORE cy is further emphasised by Ourisia fuegia- This amphi-antarctic relationship in the na, belonging to a genus referred to above, Fuego-Patagonian mountain flora reflects and Epilobium conjungens which is the an intriguing aspect of the biogeography only South American member of the genus of the whole austral American flora. Whilst having close relationships with the dis- the distribution of genera such as Notho- tinctive New Zealand species (Skottsberg fagus can be traced back to the mid- 1906, Solomons 1981 ). The final species Cretaceous break-up of Gondwanaland in this group, Saxifragodes albowiana, (e.g. Moore 1972, Humphries 1981 ), is the only member of a dependant genus this is probably not true for any of the of Saxifraga. In truth, these Fuegian orophytic taxa, with the possible excep- orophytic endemics encapsulate the prob- tion of Ourisia mentioned earlier. Certain- lems concerning the origins of the Fuego- ly, Epilobium conjungens is the solitary Patagonian montane flora, which will South American representative of a pri- now be considered. marily Australasian part of the genus (e.g. Solomons 1981), which has traversed Origins of the montane flora the southern oceans by long-distance dis- persal, for which it is well-adapted. Al- With over 80% of Fuego-Patagonian oro- though Azorella selago reaches Macquaire phytic species present also in the lowlands, Island, in the New Zealand biological it is clear that the colonisation of the region, the presence of all its congeners mountains is still in an active phase fol- in southern argues for lowing their partial emergence from the west to east distance migration, though Pleistocene ice-cover over the past few its dispersive capability is by no means thousand years. In addition to the envi- clear. The Antarctic affinities in these ronmental factors referred to earlier, the austral cordilleras are demonstrated by richer flora of the Marginal Cordilleras other examples, such as Acaena tenera may suggest that they have been longer and Colobanthus quitensis, members of ice-free and consequently available for basically circum-Antarctic genera, which colonisation. For the majority of these have probably relatively recently migrated species we have few detailed data on their from southern South American to, respec- variation patterns in relation to their tively, the Falkland Islands and South migration from lower to higher altitudes. Georgia, and Antarctica. The colonising Thus, whilst Oxalis enneaphylla, for exam- ability of the latter species is also attested ple, is very variable no correlation has yet by its migration northwards along the been discerned with its altitudinal distri- Andes to , and even beyond to Mexico bution; again, Empetrum rubrum shows (Moore 1970b). no comprehensible pattern in its morphol- Examples of even more distant affin- ogical variation, though in its chemical ities of the Fuego-Patagonian flora are constituents various trends have been shown by those species which have ar- described (Moore et al. 1970). However, rived by long-distance dispersal from the there are strong suggestions (Moore 1975) Northern Hemisphere (e.g. Raven 1963, that species such as Cerastium arvense Moore 1975). The most impressive of and Leucheria hahnii have evolved distinc- these in relation to the montane floras tive montane ecotypes, while the wide- being considered here is Koenigia islandi- spread Phaiophleps biflora contains a dis- ca first discovered by Dusén (1900), and tinctive montane element, ssp. lyckhol- described as K. fueguina, in lowland Tie- mi, in the drier Fuego-Patagonian cordi- rra del Fuego but now known from the lleras (Moore et al. 1982). Central Cordillera of the Isla Grande. A rather similar example to that of Morphologically and cytologically identical Phaiophleps is shown by Tetrachondra pa- with north temperate populations, the tagonica, in which ssp. patagonica, at mid- Fuegian immigrants apparently traversed dle altitudes to the east of the Patagonian immense distances relatively recently in cordilleras, is 'COmplemented by the oro- postglacial times. phytic Fuegian endemic ssp. fuegiana. Members of the important group of Interestingly, however, this latter subspe- Andean genera, such as Benthamiella, cies seems to have some tendencies towards Eudema, Nassauvia, Onuris and Perezia, the other, New Zealand, species of the must be the result of migrations along the genus, T. hamiltonii (Moore 1970a). mountains from the north. However, FLORA OF FUEGO-PATAGONIAN CORDILLERAS 129

their concentration and speciation in the Botanica de Patagonia Austral, jointly supported by southern parts of the cordillera suggests CONICET, , the Instituto de la Patagonia, that some of the current species may Punta Arenas, Chile, and the Royal Society of London, England. To all these organisations, and my friends, I well have evolved in ice-free refugia on the give my thanks. lowlands of what is now Argentinian Patagonia. As these areas were increasingly occupied by plants migrating from the LITERATURE CITED north as conditions ameliorated, the BRUGGEN J (1950) Fundamentos de la Geologia de other species may be visualised as being Chile. Instituto Geografico Militar. Santiago. forced into the newly available habitats DUSEN P (1900) Die Gefasspflanzen der Magellansliinder. of the cordilleras. As noted by Moore Svenska Exped Magellansl. 3: 77-266 (1973) a contributory factor in this specia- HARRINGTON HJ (1956) Argentina. In: Jenks WF (ed.) Handbook of South American Geology. tion may well have been the 'pump action' Memoirs of the Geological Society of America: described by Simpson ( 1973), in which 138-165. the advancing and retreating montane gla- HUMPHRIES CJ (1981) Biogeographical methods and the ciers of the Pleistocene alternately forced southern beeches. In: Fovey P.H (Ed.). The the plants from the mountains and allowed Evolving Biosphere. British Museum (Natural History), London: 283-297. them to return in isolated pockets -Nas- KRANCK EH (1932) Geological investigations in the sauvia /atissima (Fuegia), N. magel/anica cordillera of Tierra del Fuego. Acta Societatis (S. Andes) and N. serpens (Falkland Geographica Fennica 4: 1-231. Islands) seem to parallel the case of Perezia MOORE DM (1968) Vascular Flora of the Falkland Is- lands. British, Antarctic Survey Science Report. (Simpson 1973) as a pertinent example 60: 1-202. of this mode of evolution. MOORE DM (1970a) Additions to the vascular flora of There remains one group of Fuego- Tierra del Fuego. Boletin Sociedad Botanica Patagonian orophytic plants whose origins Argentina 13: 1-9. are difficult to explain with any certain- MOORE DM (1970b) Studies in Colobanthus quitensis (Kunth) Bart. and Deschampsia antarctica ty. The isolated genera of the austral Desv. II. distribution and relation- mountains, such as Saxifragel/a and Saxi- ships. Bulletin British Antarctic Survey 23: fragodes, and the relatively isolated Viola 63-80. tridentata within its genus, pose problems MOORE DM (1972) Connections between cool temperate floras, with particular reference to southern as to their origins. Certainly their present South America. In: Valentine DH (Ed.) Ta- occurrence cannot be explained as the xonomy, Phytogeography and Evolution. Aca- result of relatively recent immigrations demic Press, London: 115-138. from other areas, lowland or montane. MOORE DM (1974) Catálogo de plantas vasculares na- It is possible that these taxa are the results tivas de Tierra del Fuego. Anales Instituto de la Patagonia 5: 105-121. of early evolution northwards in the An- MOORE DM (1975) The alpine flora of Tierra del Fuego. des, or that they are members of groups Anales Instituto de Botanica A.J. Cavanilles. evolved in the Tertiary which survived in 32: 419-440. unglaciated 'nunataks' in the Antarctic MOORE DM (1979) Southern oceanic heaths (incl. Magellanic Moorland). In: Specht R L (Ed.). region during the Pleistocene period, as Ecosystems of the World: Heathland and rela- has been adduced for such disjunct aus- ted Shrublands. Elsevier, Amsterdam: 490- tral families as the Hectorellaceae (Philip- 497. son & Skipworth 1961 ). Only detailed stu- MOORE DM (1983) Flora of Tierra del Fuego. Anthony Nelson, Shrewsbury. dies of the fossil floras of these austral MOORE DM, JB HARBORNE & CA WILLIAMS (1970) regions might give some clue to the various Chemotaxonomy, variation and geographical possibilities. Certainly, the Fuego-Patago- distribution of the Empetraceae. Botanical nian cordilleras encapsulate the problems Journal Linnaean Society London. 63: 277-293. of trying to determine the origins of mo- MOORE DM, SC ARROYO & MC DOGGETT (1982) dern floras from their present distributions The status of Phaiophleps lyckholmt. (Dusen) RC Foster (Iridaceae). Botanical Journal and known biological affinities. Linnaean Society London 84: 103-113. PHILIPSON WR & JP SKIPWORTH (1961) Hectore- llaceae; a new family of Dicotyledons. Transac- ACKNOWLEDGEMENTS tions of the Royal Society of New Zealand, Botany 1: 31. Many of the data referred to in this paper derive from my PISANO E (1974) Estudio ecologico de la region conti- studies of the Flora of Tierra del Fuego and southern nental del área andino-patag6nica. II Contribu- Patagonia supported by the Royal Society of London ci6n a la fitogeografia de la zona del Parque and the Natural Environment Research Council of Great Nacional "Torres del Paine". Anales lnstituto Britain. Further data are the result of the Transecta de la Patagonia 5: 59-105. 130 MOORE

RAVEN PH (1963) Amphitropical relationships in the Wissenschaftliche Ergebnisse Schwedische Süd- floras of North and South America. Quarter- polarexpedition 4: 1-41. ly Review of Biology 38: 151-177. SOLOMONS JC (1981) The systematics and evolution SIMPSON BB (1973) Contrasting modes of evolution in of Epilobium (Onagraceae) in South America. two groups of Perezia (Mutiseae: Compositae) Ph. D. thesis, Washington University, USA. of southern South America. Taxon 22: 525- VUILLEMIER BS (1971) Pleistocene changes in the fau- 536. na and flora of South America. Science 17 3: SKOTTSBERG CJF (1906) Zur Flora des Feuerlandes. 771-780.

TABLE 1

Species of vascular plants occurring in the Fuego- Especies de plantas vasculares en las cordilleras Fuego- Patagonian Cordilleras, with an indication of their Patagonicas, con una indicacion de su distribucion en los distribution in the principal mountain systems. sistemas montaiiosos principales. Clave:* Restringida a la zona orofitica Key: Restricted to the orophytic zone * t No presente en Tierra del Fuego t Not present in Tierra del Fuego o Endémica de Tierra del Fuego o Endemic to Tierra del Fuego No presente en Patagonia Not present in Patagonia Restringida a la cordillera marginal de Tierra del Restricted to Marginal Cordillera in Tierra Fuego. del Fuego.

Southernmost Patagonia Eastern(Marginal)Cordillera~ Tierra Comments Andean Species Western del (See key in Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line

Abrotanella emarginata - - - - (Cass. ex Gaudich.) Cass. Ѵ A. linearifolia A. Gray - - ѴѴ Ѵ * Acaena antarticaHook. f. - - - - Ѵ A. magellanica (Lam.) Vahl ѴѴ - Ѵ Ѵ A. pinnatijida R. et P. ѴѴ - - - A. pumila Vahl - - - - Ѵ A. tenera Alboff -- - - Ѵ Adesmia corymbosa Clos Ѵ - - - - t A. lotoides Hook. f. Ѵ Ѵ - - - A. parvifolía Phil. Ѵ - - - - t A. pumila Hook. f. - Ѵ - -- A. salicomioides Speg. Ѵ v' - - - * A. silvestrii Speg. Ѵ - - - - t A. villosa Hook. f. ѴѴ - - - t Agropyron fuegianum (Speg.) - Ѵ - - - F. Kurtz A. pubijlorum (Steudel) -- - - Ѵ Parodi Agrostis flavidula Steudel Ѵ - - - - A. magellanica Lam. - - - - Ѵ Alopecurus magellanicus Lam. - Ѵ - - Ѵ Anarthrophyllum desideratum - - - - (DC.) Benth.& Jackson Ѵ Antennaria chilensis Remy - Ѵ - - - Arenaria serpens Hum b., - - -- Bonpl. & Kunth Ѵ Arjona patagonica Dcne Ѵ Ѵ - - - Armeria maritima (Miller) - - - Willd .. v' Ѵ FLORA OF FUEGO-PATAGONIAN CORDILLERAS 131

Southernmost Patagonia Eastern(Marginal)Cordilleras Tierra Comments Andean Species Western del (See key in Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line

Astelia pumi1a (Forst.f.) - - - - Ѵ Gaudich. Astragalus nivicola Gómez - Ѵ - - - - t So sa * A. palenae (Phil.) Reiche - Ѵ - ..... - A. patagonicus (Phil.) Speg. - Ѵ - - - t Azorella caespitosa Cav. ѴѴ - - Ѵ A. fuegiana Speg. Ѵ Ѵ - - - A. lycopodioides Gaudich. - Ѵ - - Ѵ A. selago Hook.f. - - Ѵ - Ѵ * A. trifurcata (Gaertner) - Ѵ - - - Hook.f. Benthamiella azorella (Skottsb.) ѴѴ - - - t Soriano * B. patagonica Speg. - Ѵ - - - t - * B. sorianoi S.Arroyo - Ѵ - - * t Berberis buxi[olia Lam. - Ѵ - - - B. empetri[olia Lam. - Ѵ - - - Bolax caespitosa Hombron & - - Ѵ Jacquinot Ѵ Ѵ B . gummi[era (Lam.) Sprengel Ѵ Ѵ - - Ѵ B ramus pellitus Hackel ѴѴ - - - aalandrinia caespitosa Ѵ Ѵ - - Ѵ Gill.ex Arn. * Calceolaria bijlora Lam. - Ѵ - - - C. palenae Phil. - Ѵ - - - t c. unijlora Lam. Ѵ - - - - antarctica Engelm. -- - - Ѵ ex Hegelm. Caltha appendiculata Pers. - - - - Ѵ c. dionei[olia Hook. f. - - Ѵ Ѵ Ѵ c. sagittata Cav. - Ѵ - - Ѵ aardamine glacialis - Ѵ - - Ѵ (Forst.f.) DC. aarex banksii Boott - - - - Ѵ c. caduca Boott Ѵ - - - - c. capitata L. - Ѵ - - - c. decidua Boott - - - - Ѵ C. maclovianaD'Urv. - Ѵ - - - c. magellanica Lam. - - - - Ѵ c. sorianoi Barros - Ѵ - - - c. subantarctica Speg. - Ѵ - - - aarpha alpina R Br. - - - - Ѵ cerastium arvense L. Ѵ Ѵ - - Ѵ Ch iliotrichum diffusum Ѵ - - - - (Forster f.) 0. Kuntze colobanthus quitensis (Kunth) - Ѵ - - Ѵ Bartl. c. subulatus (D'Urv.) ѴѴ - - Ѵ Hook. f. 132 MOORE

Southerrunost Patagonia Eastern(Marginal)Cordilleras Tierra Comments Species Andean Western del (See key in Southern, Northern, (Canales) (Central) Fuego legend) with without Cordillera Mountains tree-line tree-line

Cystopteris fragilis (L.) - Ѵ - - Ѵ Bemh. Deschampsia antarctica Desv. - Ѵ - - - D. atropurpurea (Wahlenb.) - - - - Ѵ Scheele D. parvula (Hook. f.) Desv. Ѵ Ѵ - - Ѵ Deyeuxia erythrostachya -- Ѵ - Ѵ Desv. * Donatia fascicularis Forst. - - Ѵ - - Forst. f. Draba australis R. Br. ex - Ѵ - - - Hook. f. D. fimiculosa Hook.f. ѴѴ - - Ѵ D. magellanica Lam. Ѵ Ѵ - - Ѵ D. subglabrata. (Speg.) 0. E. - Ѵ - -- t Schulz Drapetes muscosus Banks ex - - Ѵ Ѵ Ѵ Lam. Eleocharis albibracteata - Ѵ - -- Nees & Meyen ex Kunth Empetrum rubrum Vahl ex ѴѴ Ѵ - Ѵ Willd. Epilobium conjungens Skottsb. - - - - Ѵ * E. nivale Meyen - Ѵ - - - Erigeron leptopetalus Phil. - Ѵ - -- * t E. myosotis Pers. Ѵ Ѵ -- Ѵ * E. patagonicus Phil. - Ѵ -- - Escallonia serrata Sm. - - - Ѵ - Eudema hauthalii Gilg & - Ѵ - - - t Muschler * Euphorbia collina Phil. Ѵ - - - - Festuca contracta T. Kirk - - - - Ѵ F. gracillima Hook. f. - Ѵ - - - F. magellanica Lam. - Ѵ - - Ѵ F. pyrogea Speg. Ѵ Ѵ Ѵ - Ѵ Gaimardia australis Gaudich. - - Ѵ - Ѵ Gamocarpha selliana Reiche - Ѵ - -- t Gimochaeta nivalis Cabrera - - - - Ѵ G. spiciformis (Sch. Bip.) - - - - Ѵ Cabrera Geranium patagonicum - Ѵ - -- Hook. f. Geum magellanicum Comm. - Ѵ - - - ex Pers. Grammitis magellanica Desv. - - - Ѵ Ѵ Gunnera lobata Hook. f. - - - - Ѵ G. magellanica Lam. -- - - Ѵ Hamadryas delfinii Phil. ex Ѵ Ѵ - - - Reiche H. magellanica Lam. - - - - Ѵ H. kingii Hook. f. ѴѴ - - - Hieracium antarcticum D'UIV. Ѵ -- - - * FLORA OF FUEGO-PATAGONIAN CORDILLERAS 133

Southerrunost Patagonia Eastern(Marginal)Cordilleras Tierra Comments Species Andean Western del (See key in Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line

ierochloe redo/ens (Vahl) - - - - Ѵ Roemer & Schultes Hippuris vulgaris L. - Ѵ - - - Hordeum comosum C. Presl - Ѵ - - - Huanaca acaulis Cav. Ѵ - - - - Hymenophyllum falkandicum - - - - Ѵ Baker H.. peltatum (Poiret) Desv. - - - - Ѵ H.. tortuosum Hook. & Grev. - - - - Ѵ H ypochoeris incana (Hook. - Ѵ - - - & Arn.) Macloskie uncus scheuchzerioides - Ѵ - - - Gaudich. K oenigia islandica L. - - - - Ѵ t La genifera nudicaulis (Comm. - - - - Ѵ t ex Lam.) T. Dudley La thyrus magellanicus Lam. - Ѵ - - - L eucheria hahnii Franchet ѴѴ - - Ѵ L . leontopodioides (0. Kuntze) Ѵ - - - - t E. Schum. L . purpurea (Vahl) Hook. ѴѴ - - - &Arn. Luzula alopecurus Desv. - Ѵ - - Ѵ L . chilensis Nees & Meyen Ѵ - - - - L . racemosa Desv. - Ѵ - - Ѵ t L ycopodium alboffii Rolleri - - Ѵ -- t L . confertum Willd. - - Ѵ Ѵ - L. magellanicum (P. Beauv.) - - - - Ѵ Swartz arsippospermum grandijlorum - - Ѵ - Ѵ (L. f.) Hook. f. enonvillea nordenskjoldii ѴѴ - - - t (Dusén) Rollins * oschopsis rosulata (N. E. Ѵ Ѵ - - Ѵ Br.) Dusén * M . trilobata Dusén - y - - - * t Miulinum valentinii Speg. Ѵ Ѵ - - - t M yrteola nummularia (Poiret) - - - - Ѵ Berg anodea muscosa Banks ex - - - - Ѵ C.F. Gaertner ardophyllum bryoides (Lam.) - Ѵ - - - Cabrera N.. obtusifolium Hook. & Ѵ - - - - Arn. assauvia abbreviata Ѵ Ѵ - - - (Hook.& Arn.) Dusén N.. darwinii (Hook.& Arn.) - Ѵ - - - 0. Hoffm. & Dusén N.. lagascae (D. Don) F. Ѵ Ѵ - - Ѵ Meigen * N.• latissima Skottsb .. -- - - Ѵ - Ѵ * N.. magellanica J.F. Gmel. ѴѴ - * 134 MOORE

Southernmost Patagonia

Eastern(Marginal)Cordillera~ Tierra Comments Species Andean Western del (See key in Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line N. pygmaea (Cass.) Hook f. Ѵ Ѵ - - Ѵ * N. revoluta D. Don v' Ѵ - - - N. ulicina (Hook f.) Ѵ - - - - Macloskie Nothofagus antarctica - - Ѵ - - (Forst. f.) Oersted Onuris alismatifolia Gilg ex - - - - Ѵ 0 Skottsb. * 0. hatcheriana Boelcke - Ѵ - - - t - * 0. papillosa O.E. Schulz Ѵ Ѵ - - 0. spegazziniana Gilg & Ѵ Ѵ - - - t Muschler * Oreobolus obtusangulus - - Ѵ - Ѵ Gaudich. Oreopolus glacialis (Poeppig Ѵ Ѵ - - - & Endl.) Ricardi Orthachne rarijlora (Hook. - - - Ѵ Ѵ f.) Hughes Ourisia brevijlora Benth. - - Ѵ Ѵ Ѵ * 0. fuegiana Skottsb. - - - - Ѵ * 0 Oxalis enneaphylla Cav. - Ѵ - - Ѵ 0. loricata Dusén Ѵ - - - - t 0. magellanica Forst. f. - - - - Ѵ 0. patagonica Speg. Ѵ Ѵ - - - t Perezia lactucoides (Vahl) - - - Ѵ Ѵ Less. P. lanigera Hook. & Arn. - Ѵ - - - * t P. magellanica (L. f.) Lag.· - - - - Ѵ P. megalantha Speg. Ѵ Ѵ - - - * t P. pilifera (D. Don) Hook. - Ѵ Ѵ - Ѵ &Am. P. recurvata (Vahl) Less. Ѵ Ѵ - - - Pernettya pumila (L. f.) - - Ѵ - Ѵ Hook. Phacelia secunda J.F. Gmel. - Ѵ - - - Phaiophleps bijlora ssp .lyckholmii Ѵ Ѵ - - Ѵ (Dusen) D.M. Moore * Phleum alpinum L. Ѵ - Ѵ - Ѵ Phyllachne uliginosa Forst. - - - Ѵ - & Forst. f. Pinguicula antarctica Vahl - - - - Ѵ Plantago barbata Forst. f. - Ѵ - - Ѵ P. uniglumis Wallr. ex Ѵ Ѵ - - - Walpers Poa alopecurus (Gaudich.) Ѵ Ѵ - - Ѵ Kunth P. glauca V ahl Ѵ Ѵ - - - t P. rigidifolia Steudel Ѵ - - - P. secunda C. Presl - Ѵ - - - t Polemonium micranthum Ѵ - - - - Benth. Polystichum andinum Phil. - - - - * FLORA OF FUEGO-PATAGONIAN CORDILLERAS 135

Southernmost Patagonia Eastern(Marginal)Cordilleras Tierra Comments Species Andean Western del (See key in Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line

Primula magellanica Lehrn. - Ѵ - - Ѵ Ranunculus peduncularis Sm. - Ѵ - -- R. sericeocephalus Hook. f. - - - - Ѵ Rostkovia magellanica (Lam.) - - Ѵ - Ѵ Hook. Satureja darwinii (Benth.) Ѵ Ѵ - - - Briquet Saxifraga magellanica Poiret . Ѵ Ѵ - - Ѵ Saxifragella bicuspidata - Ѵ - - Ѵ (Hook. f.) Engler * Saxifragodes albowiana (F. - - - - Ѵ Kurtz) D.M. Moore * Schizeilema ranunculus - Ѵ - - Ѵ (D'Urv.) Domin Schoenus antarcticus (Phil.) - - - - Ѵ Pfeiffer Senecio acanthifolius - - Ѵ - Ѵ Hombron & Jacquinot S. alloeophyllus 0. Hoffm. Ѵ Ѵ - - Ѵ * S. boelckei Cabrera Ѵ - - - - t S. culcitenellus Cuatrec. - Ѵ - - - t S. darwinii Hook. & Arn. - - - Ѵ Ѵ * S. eightsii Hook. & Arn. - - - - Ѵ S. humi[usus (Hook. f.) - - - - Ѵ Cabrera S. kingii Hook. f. - - Ѵ - Ѵ S. laseguei Hombron & Ѵ Ѵ - - - Jacquinot S. mageUanicus Hook. & Arn. Ѵ Ѵ - - Ѵ S. martinensis Dusén - Ѵ - - - t S. miser Hook. f. - Ѵ - - - S. patagonicus Hook. & Arn. - - - - Ѵ S. tricuspidatus Hook. & - - - - Arn. Ѵ S. tri[urcatus (Forst. f.) - - - - Ѵ Less. Serpyllopsis caespitosa - - - Ѵ Ѵ (Gaudich.) C. Chr. Silene patagonica (Speg.) Bocquet Ѵ - - - - * t S. chilensis (Naudin) Bocquet - Ѵ - - - t Sisymbrium magellanicum Ѵ - - - - (Pers.) Hook. f. Sisyrinchium arenarium - Ѵ - - - t Poepp. S. iridifolium Hum b., Bonpl. - Ѵ - - - t &Kunth S. junceum E. Mey. ex C. - Ѵ - - - t Presl. Stipa humilis Cav. - Ѵ - - - Tapeinia obscura (Cav .) D. M. - - Ѵ Ѵ Ѵ Moore * Taraxacum gilliesii Hooker & - Ѵ - - Ѵ Arn. 136 MOORE

Southernmost Patagonia Eastern~arginal)Cordilleras Tierra Comments Species Andean Western del (See key in . Southern, Northern, (Central) (Canales) Fuego legend) with without Cordillera Mountains tree-line tree-line

Tetrachondra patagonica ssp. - - - - Ѵ fuegiana D.M. Moore * Thlaspi magellanicum Comm. - - - ex Poir. Ѵ Ѵ Tribeles australis Phil. - - Ѵ - Ѵ Trisetum spicatum (L.) K. - - Richter Ѵ Ѵ Ѵ Tristagma nivale Poepp. Ѵ Ѵ - - Ѵ Uncinia kingii Boott - - - Ѵ Ѵ * U. lechleriana Steudel - - - - Ѵ Valeriana magellanica Hom bron - - - - & Jacquinot ex Dcne Ѵ V. sedifolia D'Urv. Ѵ Ѵ - - - Verbena azorelloides Speg. Ѵ Ѵ - - - *t Vicia bijuga Gillies ex - - - Hook. & Arn. Ѵ Ѵ Viola commersonii DC. - - - Ѵ Ѵ V. tridentata Menz. ex DC. - - Ѵ Ѵ Ѵ Xerodraba glebaria Skottsb. - Ѵ - - - t X pectinata (Speg.) - Ѵ - - - * Skottsb. * t