Malvaceae neotropicae novae vel minus cognitae X. New species of Quararibea from Colombia and Ecuador

In this advance of the taxonomic revision that is being carried out in the genus Quararibea (Malvaceae) for the north of South America, three new species are described in this contribution, which are compared morphologically with the species considered related in each case. A first, Q. cornejoi, known from the wet forests of western Ecuador that we associate with Q. grandifolia and Q. casasecae, taxa also distributed in the Pacific corridor of Ecuador and Colombia. A second species, Q. latilimbata, from the sub-Andean forests of the Central Cordillera of the Department of Antioquia, Colombia, related to the previous species and to the Amazonian species Q. duckei. All of them with an unusual trait in the genus, an androecium with the long staminal branches. Finally, Q.villanuevae, from the dry forests of the upper Magdalena Valley in the Department of Tolima, Colombia, associated with the Andean species Q. foenigraeca and Q. caldasiana. These last three species, which have androecium with smaller staminal branches, are assigned to a different morphological group. Illustrations and detailed photographs of the new species are included as well as keys to the identification of the treated species.

Two new species of Andinia (Pleurothallidinae) from the Central Cordillera of Peru

Two new Andinia species are described, A. barba-caprina and A. crassipetala, both found during a botanical expedition to the montane forests of the Central Cordillera of the Peruvian Andes. They are compared with morphologically similar species, and Lankester Composite Dissection Plates (LCDP) are provided. Andinia barba-caprina is more similar to A. tingomariana but is distinguished by having obovate sepals with sparsely erose margins and the lip with narrowly obtuse, short basal lobes and a group of large hairs on the abaxial surface. Andinia crassipetala is distinguished from the two most similar species, A. hernandoi Est.Domínguez & S.Vieira-Uribe and A. persimilis (Luer & Sijm) Karremans & S.Vieira-Uribe for having thick, deltate and obtuse petals.

Ecologia e composição briofítica de uma floresta urbana da central Cordillera de Los Andes, Colômbia / Ecology and briophytic composition of an urban forest of the central Cordillera de Los Andes, Colombia

El estudio de los briofitos que habitan en ambientes urbanos resulta ser interesante. Dentro del grupo de las Briofitas predominan especies oportunistas, capaces de tolerar contaminantes y cambios ambientales drásticos. Algunos estudios sobre la brioflora urbana, reconocen la existencia de especies tolerantes a las variables ambientales y toxitolerantes y otras más sensibles de aparición esporádica. Se muestreo un bosque urbano premontano considerado húmedo en el pie de monte vertiente occidental de la cordillera central de los Andes. Se utilizó la metodología ISA de 50 x 4 mt, dividiendo este bosque en dos coberturas: borde e interior, con el objetivo de comparar la ecología y composición entre las dos. Además se implementó la metodología RAP, analizándose los morfos epifitos, con el objeto de evaluar la mayor cantidad de sustratos. Por otra parte se tomaron variables ambientales en ambas coberturas, con el fin de contrastar resultados. Se registraron 113 especies, tres variedades y dos subespecies, distribuidas en 47 familias y 73 géneros. La división Bryophyta presentó el mayor número de especies, géneros y familias; las hepáticas (Marchantiophyta) son el segundo grupo con mayor cantidad de especies y los Anthocerotophyta (Anthoceros) con el menor número de especies. Se obtuvieron diferencias significativas y contrastantes en cuanto las variables ambientales y ecología en las dos coberturas.

Biodiversity in the Andean Mountains: Two new rain frogs of the genus Pristimantis (Anura: Craugastoridae) from the northern Cordillera Central in Colombia

Frequent biodiversity sampling and monitoring programs often lead to relevant taxonomic findings. Here, as a product of different field expeditions to two places in the northern Andes, we discover and describe two new species of rain frogs of the genus Pristimantis from the cloud forests of the Central Cordillera of Colombia. Pristimantis chocolatebari sp. nov. is diagnosed by having the following character states: dentigerous process of vomer triangular, snout large and protruding, dorsum smooth, vocal slits and vocal sac present, groin and hidden part of the thighs yellow. Pristimantis carylae sp. nov. is diagnosed by having iris copper red, dentigerous process of vomer oval, snout short and rounded, dorsum finely shagreen with scattered tubercles, double nuptial pad in males, groin and hidden part of thighs pink. We also infer, for the first time, the phylogenetic position of P. permixtus, P. platychilus, and two candidate new species. In addition, we emphasize not to use genetic distance as the only source of evidence for species delimitation, considering the high intraspecific diversity found in one of the species described here. Finally, we highlight the relevance of different habitat and ecosystem conservation strategies to promote amphibian diversity studies in the Andes.

Pleistocene plants from Zarzal Formation, middle valley of the Cauca River Basin, Colombia

We report macro and meso palaeobotanical records from the Zarzal Formation, in the Cauca River Depression, and the Quindío-Risaralda Basin between the Western and the Central Cordilleras of Colombia. The fossils correspond to leaves and seeds obtained from layers of mudstones, diatomites, and tuffaceous sandstones deposited in the inter-Andean valleys of Cauca and La Vieja rivers, separated by the Serranía Santa Bárbara ridge between the Valle del Cauca and Quindío departments. The sediments of the Pleistocene Zarzal Formation were deposited in a fluvial-lacustrine environment, with volcanic influence originated in the Central Cordillera to the east of the depositional area. The study here presented allowed the identification of thirteen morphotypes of leaf impressions grouped in six Angiosperm families: Poaceae?/Cyperaceae? and Araceae of the Monocots group, Melastomataceae, Fabaceae and Lauraceae belonging to the Eudicots group and one family of Lycopsida: Thelypteridaceae. On the other hand, very well-preserved silicified micro-seeds were grouped in eight morphotypes, belonging to the botanical groups Cyperaceae and Asteraceae. The fossils found allowed us to identify two types of plant associations that exhibit paleofloristic richness. In the Cauca River Basin, an autochthonous to parautocthonous plant association could correspond to a sub-Andean gallery forest, whilst in the La Vieja River Basin a parautocthonous plant association indicates a swamped floodplain. Keywords: paleoflora, leaves, seeds, Cauca River, La Vieja River, lacustrine deposit.

Comment on “Emplazamiento del magmatismo Paleoceno-Eoceno bajo un régimen transtensional y su evolución a un equilibrio dinámico en el borde occidental de Colombia” by Grajales et al., Rev. Mex. Cienc. Geol. (2020), 37(3), 250-268

Grajales et al. (2020) reviewed geochronological and geochemical data from Paleogene volcanic and plutonic rocks outcropping in the Panama-Choco Block (north western Cordillera) and southern Western Cordillera, as well as the Central Cordillera of Colombia. These data were used to support a model of continuous Paleogene arc magmatism along the Colombian continental margin, and to propose a paleogeographic model for the arc. The authors did not discuss previously published paleomagnetic, geochemical, geochronological, thermochronological and provenance constraints from Cretaceous to Miocene rocks of western and northern Colombia, Panama, and Ecuador that support a more plausible model of a double subduction system controlled by the convergence of the Caribbean and Farallon plates beneath the north Andean block during Paleogene. In this comment, we discuss shortcomings in the data and model proposed by Grajales et al. (2020) and present an alternative interpretation for contemporaneous arc-like magmatism during the Paleogene in the Northern Andes. We conclude that the double subduction system is the more plausible explanation for the contemporaneous arc-like magmatism during the Paleogene, currently exposed in the northern and southern portions of the Northern Andes.

Description of six new species of Xenorhina Peters, 1863 from southern Papua New Guinea (Amphibia, Anura, Microhylidae)

We describe six new species of the microhylid frog genus Xenorhina from the southern slopes of Papua New Guinea’s central cordillera and adjacent lowlands, based on a combination of morphological (including osteology) and bioacoustic features. All of the new species are fossorial or terrestrial inhabitants of tropical rainforest habitats and belong to a group of Xenorhina having a single, enlarged odontoid spike on each vomeropalatine bone. Advertisement calls and habitat preferences are described for each species, one of which is amongst the smallest hitherto members of the genus. Description of these six species brings the total number of Xenorhina known to 40 and emphasises the importance of the high-rainfall belt that extends along the southern flanks of New Guinea’s central cordillera as a hotspot of Melanesian amphibian diversity.

Phenology of the endangered palm Ceroxylon quindiuense (Arecaceae) along an altitudinal gradient in Colombia

Introduction: Understanding the phenology of plant populations is vital for their conservation and management. We studied the vegetative and reproductive phenology of the endangered palm Ceroxylon quindiuense along an altitudinal gradient in the Central Cordillera of Colombia. Objective: We describe the leaf production rate, and flowering and fruiting cycles, and calculate food offer for the fauna, as a tool for the proper management of the palm. Methods: At each sampling site (2 400, 2 600, 2 800, 3 000 m.a.s.l.), we marked 40 adult individuals (20 pistillate, 20 staminate), which we followed bimonthly for 24 months. We studied leaf production by counting fallen leaves. We followed flower and fruit production through observations with binoculars and photographs. Results: Each adult individual produced, on average, one leaf every 61 days. Although isolated individuals flowered throughout the year, most palms flowered synchronously at each elevation in October 2016-August 2017 and in August 2018-February 2019 and had ripe fruits 7-13 months later. Flowering started at 2 600 m, followed by 2 800 and 3 000 m. Palms at 2 400 m, the lower limit of the palm stands in the area, showed a singular behavior, with scarce flower and fruit production, some individuals that changed sex, and a higher proportion of pistillate palms. Each palm produced 1-11 (x̄ = 5.3, SD = 2.2) inflorescences and 1-10 (x̄ = 5.3, SD = 2.2) infructescences. The average number of fruits per infructescence was 4 465 (SD = 1 488). With an estimated population of adult palms between 256 000 and 600 000 and an overall ratio of pistillate: staminate individuals 1:1 or 1:2, total fruit production in the area during each fruiting period is estimated as 2.0-7.1 billion fruits. Conclusions: The huge number of flowers and fruits and their gradual availability along the altitudinal gradient have a major impact on the spatial and temporal distribution of food offer for fauna associated with the palm.

Plecturocebus caquetensis (Primates: Pitheciidae)

Plecturocebus caquetensis (Defler, Bueno, and García, 2010) is a Neotropical primate commonly called the Caquetá titi monkey. It is small-sized with long, soft pelage of mixed coloration including grayish and buffy brown to agouti tones. It lacks the blackish or whitish band that is present on the forehead of closely related species. The tail is agouti-colored and slightly banded at its base. Endemic to the Amazonian region of Colombia with a distribution in areas near the eastern slopes of the Eastern and Central Cordillera of the Andes, P. caquetensis is confirmed in 104 localities in the departments of Cauca and Caquetá in Colombia. P. caquetensis is considered “Critically Endangered” (CR) by the International Union for Conservation of Nature and Natural Resources.