Gayana Botanica

Expansion of the south american distribution of Aristida friesii Hack. ex Henrard (Poaceae)

Harol Gutiérrez — 2026-08-08

Aristida friesii (Poaceae) is reported for the first time in Peru, occurring on rocky high-Andean plains of Azángaro, Puno (4000–4100 m a.s.l.), thereby extending its previously known distribution from Argentina and Bolivia. Ecological niche modelling using MaxNet was employed to generate a potential distribution map, indicating altitude and annual temperature as the main environmental drivers of its distribution. This record raises the number of Aristida species documented in Peru to 21 and is accompanied by a detailed morphological description and illustrations, contributing to the understanding of high-Andean Poaceae diversity and biogeography.

Valeriana tunuyanense Méndez (Caprifoliaceae): New species for the vascular flora of Chile

Luis Retamal Pacheco — 2026-08-08

Valeriana tunuyanense Méndez (Caprifoliaceae), a saxicolous species, previously considered endemic to the Mendoza Province, Argentina, is reported. The species was discovered on cerro Punta Ventanas in the Chilean Andes, Metropolitan Region of Santiago. A description of the species, images of leaves, flowers and fruits together with distribution and habitat details are provided.

Diversity of arbuscular mycorrhizal fungi in coffee plantations with different shade types in Chiapas, Mexico

Kristell Karina Robles-González — 2026-08-08

Arbuscular mycorrhizal fungi (AMF) live in symbiosis with most vascular plants, through which they can enhance nutrient uptake and plant growth. This study aimed to evaluate the abundance, richness, and diversity of AMF in coffee crops (Coffea arabica L.) under different types of shade during the dry and rainy seasons in Chiapas, Mexico. The study was conducted in the coffee-growing region of the Highlands of Chiapas, in nine coffee plantations: three without shade, three with simple shade, and three with mixed shade. Soil samples were collected around the roots of coffee bushes and processed for physical and chemical analysis, spore density, and morphological species identification. A total of 38 AMF species were identified, with Acaulospora being the predominant genus. The highest abundance occurred during the dry season in coffee plantations with diverse shade, with 266.4 (±45.3) spores/50 g of soil, Shannon-Wiener diversity of 2.40 (±0.32), observed richness of 26.7 (±5.6). Among the species found, Acaulospora tuberculata, Glomus pansihalos, and Rhizophagus manihotis are new records for Mexico. In conclusion, the dry season and diverse shade in the coffee plantation had a positive effect on the abundance, diversity, and species richness of AMF.

Effects of temperature, water availability, and elevation on the germination of epiphytic bromeliads under controlled and field conditions

Diana C. Gómez González — 2026-08-08

We evaluated the effect of temperature, water availability and altitude on the germination of three epiphytic bromeliad species: Guzmania glomerata, G. stenostachya, and Werauhia macrochlamys. Under controlled conditions, water availability did not significantly affect germination, but increased temperature reduced germination success, especially in Guzmania. In the field, germination was significantly lower at lower-altitude sites, mirroring the thermal effects observed in the laboratory. W. macrochlamys showed greater relative thermal tolerance. These results indicate that temperature is a key limiting factor for the germination of epiphytic bromeliads and suggest their potential as bioindicators of climate change in Neotropical ecosystems.

Cytogenetic study of the ecotypic variety of maize from Calama, northern Chile

Oscar Mendoza Olivares — 2026-08-08

The ecotypic variety of maize from Calama, known as “choclo calameño,” is cultivated in the surroundings of the highland city of Calama at an altitude of 2,400 m a.s.l. in northern Chile. However, factors such as urban expansion, the reduced flow of the Loa River, and the sale of agricultural land have drastically decreased its cultivation, placing this variety at risk of extinction. Currently, no cytogenetic information is available for this maize, which is essential for its conservation and genetic improvement. Therefore, the objective of this study was to characterize the structure and number of its chromosomes. Cytogenetic analysis determined a chromosome number of 2n = 20, with the following karyotypic formula: 5M + 4SM + 1SM/SAT. These results provide a fundamental basis for understanding aspects of its genome and applying this knowledge to the genetic improvement of the variety. Furthermore, the study highlights the importance of Calama maize as biological heritage and as an ecotypic resource with economic and social value.

Potential distribution, anatomy, chemistry, and energetic characteristics of Baccharis heterophylla: an ecologically valuable species in the Sierra Juárez, Oaxaca, Mexico

Mario Ernesto Suárez-Mota — 2026-08-08

The Sierra Juárez de Oaxaca is a privileged region due to its enormous water catchment capacity and remarkable biological diversity. The objective of the present research was to determine the current status of secondary forests in the Sierra Juárez de Oaxaca. Data on the anatomy of the species were described according to IAWA recommendations. Chemical and energetic components were determined using ASTM standards. Elemental analysis was carried out using the semiquantitative technique with an Inductively Coupled Plasma Mass Detector. Regarding the potential water recharge zones in secondary forests, the possibility of very high, high and medium water recharge was observed. The values of anatomical, chemical and energetic composition showed a reduced variation in the three sites studied: 8.03 % extractives, 22.52 % lignin and 68.36 % holocellulose, 10.96 % moisture, 96.95 % volatile material, 0.85 % ash, 31 % fixed carbon, 27.16 MJKg^-1 in higher calorific value and 23.90 MJKg^-1 for lower calorific value, the above results show that the wood of B. heterophylla Kunth is ecologically important and suitable for use as fuelwood. In general, it is recommended to pay attention to secondary forests because they are key in the supply of what is known today as environmental goods and services.

Chile: Taxonomic revision of Ombrophytum subterraneum (Aspl.) Hansen (Balanophoraceae)

Oriana Pardo B. — 2026-08-08

This paper reviews the taxonomic history of northern Chile, frequently cited in the ethnobo Ombrophytum subterraneum (Aspl.) B. Hansen, a species from tanical literature. This revision is necessary in response to the proposal by Kuijt & Delprete (2019), who, based on the observation of a photograph of a specimen collected in the locality of Lasana (Antofagasta Region), argue that it belongs to a different species that they name Ombrophytum chilensis. The formal registration of the new taxon raises doubts that must be clarified to determine which of the two species the numerous Chilean ethnobotanical studies refer to. The general conclusion is that the identifying characteristics provided are not conclusive to accept the new name for the Chilean flora.