Gayana Botanica

Characterization of the karyotypic morphology of Haplopappus foliosus (Hook. & Arn.) (Asteraceae)

Marcelo Miranda-Cavallieri — 2025-08-01

The characterization of the chromosomal morphology of Haplopappus foliosus (Hook. & Arn.) determined a chromosomal number of 2n = 10, with a karyotypic formula of one subtelocentric pair (st) and four submetacentric pairs (sm). The intrachromosomal asymmetry index (A1) and interchromosomal asymmetry index (A2) showed a moderate tendency towards telocentricity and low variability in the sizes of chromosome pairs.

Usnea dimorpha (Mül. Arg.) Motyka (Parmeliaceae, Lecanoromycetes) new record from Argentina and Chile

Francibelk Roa-Garcia — 2025-08-01

Based on a study of the diversity of the genus Usnea in southern Chile and the review of specimens collected in Patagonia of Argentina, a new species is reported from both countries: Usnea dimorpha (Mül. Arg.) Motyka. Its morphological, anatomical and chemical characteristics are described. Also, its distinctive characters are discussed in relation to other species of the genus in the region.

Minthostachys (Lamiaceae), genus and species new for Chile

Melica Muñoz-Schick — 2025-08-01

A specimen of the genus Minthostachys is collected for the first time in the North of Chile. In this difficult genus, this specimen is associated to M. acris Schmidt-Leb., till now from Perú.

Type material deposited at the Diatom Herbarium (DIAT-CONC), University of Concepción, Concepción, Chile

Patricio Rivera — 2025-08-01

The Diatom Herbarium of the University of Concepción, Chile (DIAT-CONC), hosted by the Department of Botany, Faculty of Natural and Oceanography Sciences. At present it hosts 7,812 slides and 3,553 containers with raw and clean material collected from marine, brackish and freshwater habitats. Among them, there are divers Collections of diatoms, and the types of 40 new species or genera. Detailed information of each type is given. Also, we propose four new taxonomic combinations.

Potential pollinators and capsule formation in four Chloraea (Orchidaceae) species from south-central Chile

Guillermo Pereira — 2025-08-01

We studied the potential pollinators of four Chloraea orchid species that grow sympatrically in Central- South Chile. We recorded potential pollinator visits, and evaluated capsule formation after 30 days. Results revealed Coleoptera and Hymenoptera species as potential pollinators, with no specific preference for any orchid species. Many visited flowers aborted, leading to low capsule formation, especially in C. lamellata. These findings enhance our understanding of Chilean orchid biology, aiding in their conservation efforts.

The genus Crenotia (Bacillariophyta) from Chilean Altiplano: First record of C. rumrichorum (Lange-Bertalot) Wojtal for the Salar Aguas Calientes, and comments about its morphological features

Patricio Rivera — 2025-08-01

Two species of the genus Crenotia Wojtal are known to be present in Chile: C. thermalis (Rabenhorst) Wojtal and C. rumrichorum (Lange-Bertalot) Wojtal. Using light and electron microscopy, we studied and comment the morphological features of C. rumrichorum from Salar Aguas Calientes and Punta Negra. The species is recorded for the first time from Salar Aguas Calientes.

Potential distribution and influence of climatic change on Baccharis conferta Kunth (Asteraceae) on an altitudinal gradient

María Guadalupe Ruiz-Gómez — 2025-08-01

The effects of climate change on biodiversity include the displacement, increase, reduction, or extinction of species. Potential distribution models allow us to identify their ecological niche and infer species’ responses to climate change. The objectives of this work were to model the potential distribution of Baccharis conferta under climate change scenarios, to determine the area that will be protected in the future in Natural Protected Areas (NPA), and to evaluate the effect on the altitudinal change of the species under climate change scenarios. MaxEnt modeled the current potential distribution and scenarios for the years 2050 and 2070, with concentrations of 538 and 936 ppm of CO₂. In addition, the areas lost, gained, and stable in both scenarios were compared. The variables most important in the distribution were the mean temperature of the driest season, the seasonality of temperature, and the precipitation of the coldest season. Despite being a species with a wide distribution in the Transverse Neovolcanic Axis, future scenarios show a reduction of up to 93 % of its current potential distribution, taking refuge at higher elevations. In addition, the area of B. conferta that will be protected in the future in NPA is exceptionally low, highlighting the need to expand or establish new ones based on future distribution models. NPA, especially those with altitudinal gradients and microclimates capable of mitigating climate change, play a crucial role as a refuge for biodiversity in temperate ecosystems. We observed a significant decrease in the elevation range between the present and all future scenarios, reducing in the future scenarios. Conservation planning must adapt to climate change predictions to ensure the survival of species such as B. conferta.

Vascular flora in plantations dominated by Coihue (Nothofagus dombeyi) and Raulí (Nothofagus alpina)

Mario Romero-Mieres — 2025-08-01

The present study aimed to understand the richness and diversity of vascular flora in plantations dominated by Coihue (Nothofagus dombeyi) and Raulí (Nothofagus alpina), mainly located in the Los Ríos region, although the sampling included plantations between approximately 37º15’ and 41º15’ S, in both mountain ranges and intermediate depression. During the years 2022 and 2023, 40 plantations ranging from 13 to 81 years of age, with and without forest management, were floristically surveyed. In each of them, five rectangular plots of 100 m² were established, recording the vascular floristic composition and their coverages. The results indicate a general richness of 154 taxa distributed in 69 families and 120 genera. A total of 133 taxa were recorded in Coihue plantations and 138 taxa in Raulí plantations. The general phytogeographic origin for both plantations show the dominance of native and endemic species, with perennial herbs being the most frequent. The Asteraceae family is the most representative, with 14 species (22 %). The genus with the most representatives is Blechnum L., with five species. The reported flora includes 9,1 % of species with conservation problems in Chile, with one species in the “Endangered” category, Berberidopsis corallina. Diversity is high, with significant differences in species composition. As the age of the Coihue and Raulí plantations increases, the floristic assemblage becomes more diverse, similar to those recorded in other areas with natural Coihue and Raulí forests.

First contributions to the knowledge of lichens in ecosystems of Paso Pehuenche, Maule Region, Chile

Iris Pereira — 2025-08-01

This study highlights the diversity of lichens distributed in the Paso Pehuenche area (km 121), a zone with no previous records of this group. The general objective was to contribute to lichen communities’ knowledge and understand the abiotic and biotic factors influencing their ecological distribution. The specific objectives were: (a) to know lichen diversity, (b) to determine the conservation status of the lichen species present in the area, and (c) to characterize the substrates they inhabit. The results reveal that lichen diversity is represented by 19 taxa (17 species and 2 genera), growing on three substrates: rocks, soil, and the bark of Austrocedrus chilensis. On rocky substrates, notable saxicolous species include Acarospora strigata, A. xanthophana, Lecidea atrobrunnea, Lecidea sp., Melanelixia fuliginosa, Ochrolechia austroamericana, Rhizocarpon geminatum, Rhizocarpon geographicum, Rhizoplaca melanophthalma, Umbilicaria hyperborea, Xanthoparmelia mougeotii, and one muscicolous species, Lepraria membranacea. Among corticolous species, Canoparmelia austroamericana, Collema sp., Lecanora albella, Lecidella elaeochromma, Physcia adscendens, Polycauliona candelaria, and Rinodina sophodes were identified. The most common reproductive strategy was sexual reproduction, followed by asexual reproduction (soredia). Of the total taxa identified, only 15.8 % have a conservation status in Chile, while 84.2 % remain uncategorized. These findings position these lichens as potential bioindicators in climate change, considering their reproductive strategies, photobiont types, and the substrates they colonize. These factors should be integrated into future efforts to categorize lichen species in Chile.

Delimitation of genetic conservation units for Dysopsis hirsuta (Müll. Arg.) Skottsb. (Euphorbiaceae), an herb endemic to Juan Fernández Archipelago, Chile

Glenda Fuentes — 2025-08-01

Juan Fernández Archipelago is made up of islands: Robinson Crusoe, Santa Clara and Alejandro Selkirk and it has high endemism in its small area, and it was declared as Chilean national park, a biosphere reserve and a global biodiversity hotspot. The past introduction of invasive plant and animal exogenous species together with the human activities resulted in species loss and populations damage, affecting the genetic diversity within its endemic species. The aim of this study was to mark out genetic conservation units, also known as ESUs, for the endemic herb Dysopsis hirsuta, within its whole distribution range in Robinson Crusoe Island. Genetic diversity and structure parameters were obtained from AFLP and SNPS molecular markers from samples collected from 321 plants, making genotyping 113 individuals from 9 localities. Results led to marking out three genetic conservation units with populations in Mirador Selkirk-Plazoleta El Yunque, Salsipuedes and Rebaje la Piña, Vaquería y Puerto Inglés. The selection of these units may help in making better conservation strategies, since it separates the genetic singularities shared by populations within each unit. Additional conservation efforts in these three units are encouraged, using tools as seed banking, considering these units in conservation management plans including also La Campana locality, in order to increase the genetic variation levels and to carry out special monitoring to Salsipuedes population due to its singular genetic patterns revealed in the study.

Evolutive-biogeographic history of the flora of subtropical forests in Central Chile

Carolina Villagrán — 2025-08-01

Central Chile exhibits a unique biogeographic combination of Neotropical and Austral-Antarctic floristic components, a mixed character recognized by the distinction of a “Chilean Province” and its status as an interface between two major biotas with Gondwanan roots. Using phylogenetic, phylogeographic, and paleobotanical evidence, we examine the main woody genera of the sclerophyllous forest of Central Chile belonging to these two biogeographic elements, and their differentiation associated with the complex tectonic-climatic factors that occurred during the Cenozoic. The geographic isolation associated with the fragmentation of Gondwana during the Paleogene is illustrated by Drimys, Aextoxicon, and Gayella, and similar cases are discussed. The Neotropical component, differentiated during the Neogene, is exemplified by Myrceugenia, Escallonia, Azara, and Jubaea/Cocoseae, now disjunct with the eastern Andes, and analogous discontinuities are discussed. By the end of the Neogene, through the cases of Archidasyphyllum/Barnadesioideae, Porlieria, and Vasconcellea, the radiation of the xeric Neotropical Element linked to the Andean uplift and development of the Arid Diagonal of South America and the Atacama Desert is considered. The role of Pleistocene climate changes in the distribution of forests in Central Chile is discussed. This period was marked by the expansion of populations of various Austral- Antarctic species, particularly Nothofagus and conifer species, to lower latitudes during the wetter glacial periods. Based on phylogeographic evidence, the fragmentation of sclerophyll and fog communities during the arid periods of the Holocene is described, a process exemplified by Cryptocarya alba, Myrceugenia correifolia, Aextoxicon punctatum, and Drimys winteri.