Pacific Lowlands Research Articles

The History of a Periphery: Spanish Colonial Cartography from Colombia's Pacific Lowlands

The History of a Periphery: Spanish Colonial Cartography from Colombia's Pacific Lowlands

BIOGEOGRAPHIC PATTERNS OF COLOMBIAN FROGS AND TOADS

Using the data provided in Ruiz-Carranza et al. (1996) the distributions of the 540 species of frogs and toads are partitioned among ten ecogeographic units of Colombia defined on the basis of precipitation and elevation. Sorne lowlands areas (Pacific lowlands, Amazonia) exhibit high diversity (85-94 species) but lowlands areas in general are impoverished (30-52 species), especially when contrasted with upland areas. The three Andean cordilleras harbor between 87 and 121 species of frogs and toads, demonstrating that the biodiversity of Colombia resides primarily in its montane components, not in its lowland rainforests. When biological endemicity is separated from political endemicity, five areas of high endemicity remain (the three Andean cordilleras, the Sierra Nevada de Santa Marta, and the Pacific lowlands). We endeavor to explain this description by recourse to cladistic analyses of several groups of leptodactylid frogs where we find that the general pattem of diversification is by meaos of horizontal diversification (allopatric speciation) with a minor contribution from vertical diversification.

Revisiting the biogeographical regionalization of the Pacific Lowlands biogeographical province using bird distributional data

Abstract The individual tracks of 47 bird species endemic to the Pacific Lowlands biogeographical province, which belongs to the Mesoamerican dominion of the Neotropical region, were used to revise its biogeographical regionalization. As a result, the six biogeographical districts previously recognized are classified in two subprovinces: the Coastal Lowlands of Nayarit-Sinaloa subprovince, stat. nov., which includes the Sinaloan, Tres Marías Islands, Revillagigedo Islands, and Guerreran districts; and the Coastal Lowlands of Southwestern Mexico subprovince, stat. nov., which includes the Tehuanan and Tapachultecan districts. Bird species supporting the biogeographical subprovinces and districts recognized are listed. The recognition of the subprovinces encompassing the districts represents an improvement of this biogeographical regionalization.

Juliet B. Wiersema. The History of a Periphery. Spanish Colonial Cartography from Colombia's Pacific Lowlands. Austin: University of Texas Press, 2023. 168 páginas.

El libro de Juliet B. Wieserma, editado bajo el título que provisionalmente podríamos traducir como Historia de una periferia. Cartografía del período colonial sobre el Pacífico colombiano, llega entonces en un momento en el que es posible hablar de cierta madurez en los debates en torno a la cartografía como documento para la investigación en historia. Al interior de estos debates han surgido interrogantes clave, como, por ejemplo: ¿qué tipo de proyectos políticos y económicos pueden leerse en el lenguaje de los mapas?, ¿cómo se expresan las tensiones sociales y étnicas en torno al territorio a través de la cartografía?, ¿qué nos dicen los mapas acerca de la construcción de jerarquías sociales ancladas en el espacio?

Jennifer Saracino. Review of "The History of a Periphery : Spanish Colonial Cartography from Colombia's Pacific Lowlands" by Juliet B. Wiersema.

Jennifer Saracino. Review of "The History of a Periphery : Spanish Colonial Cartography from Colombia's Pacific Lowlands" by Juliet B. Wiersema.

Trophic position determines the persistence of neotropical understory birds after forest disturbance.

Habitat loss and degradation are key drivers of the current biodiversity crisis. Most research focuses on the question of which traits allow species to persist in degraded habitats. We asked whether a species' trophic position or niche width influences the resilience of species in degraded habitats and to what extent habitat degradation affects trophic interactions between species. We used nitrogen isotope ratios (15N:14N, expressed as δ15N value) to quantify and compare trophic positions and niche widths of understory birds inhabiting old-growth and young secondary forests in the Pacific lowlands of Costa Rica. We found that a species' trophic position rather than its trophic niche width determined its persistence in secondary forests. Species feeding at lower trophic levels in old-growth forests were less likely to persist in secondary forests than those occupying a higher trophic position in old-growth forests. This pattern is likely induced by the occurrence of relatively large-bodied habitat specialists with a flexible and high-trophic level diet in secondary forests. These habitat specialists likely caused generalist bird species to lower their trophic position relative to conspecifics in old-growth forests. Regarding trophic niche widths, species in secondary forests tend to have larger niche widths than old-growth forest species. However, as old-growth forest specialists and generalists did not differ in their niche widths, no systematic effect of trophic niche width on species persistence after forest disturbance was found. This is the first study that shows a systematic effect of trophic position on the persistence of a wide range of bird species in a disturbed forest ecosystem. It therefore provides important insights into species' responses to habitat degradation and the conservation value of secondary forests. To improve habitat quality for old-growth forest birds and facilitate avian seed dispersal, the creation of large contiguous forest patches should be prioritised when implementing reforestation measures.

The official presentation to science of a new species of Hechtia (Bromeliaceae: Hechtioideae) from the Pacific Lowlands in Mexico

Background: Hechtia is characterized by its terrestrial, succulent rosettes, dioecy, and unisexual, dimorphic flowers, mainly fragrant. The paucity and fragmentary herbarium material limit the species recognition but living material reveals diagnostic characters to delimitate them.
 Hypothesis: Hechtia species are circumscribed by a combination of vegetative and floral characters of both sexes. If the new taxon does not share morphological characters with other species, it will be described as new.
 Taxon: Hechtia.
 Study site and dates: Chamela-Cuixmala Biosphere Reserve, Jalisco, 1985-2023.
 Methods: Field collected, cultivated as well as herbarium material of the new taxon were analyzed and compared to other species from the Pacific Lowlands and adjacent areas, particularly flowers of both sexes, fruits, and seeds. Conservation status using IUCN criteria is reported for the new species.
 Results: Specimens of Hechtia chamelensis have been misidentified as H. laevis and H. reticulata (both described from fruiting, fragmentary specimens) but the fruit and seed features of both taxa do not match those of the new species. H. chamelensis is known from the Chamela-Cuixmala Biosphere Reserve and it is characterized by strict sympodial growth pattern, green leaves with red hues, shiny and glabrous above, white lepidote below, panicles usually simple to (rarely staminate ones) 2-divided, staminate flowers pinkish to pale white, pistillate with pale green to white petals.
 Conclusions: Vegetative and reproductive features as well as geographical distribution allow the recognition of H. chamelensis as a new species native from Jalisco, Mexico.

An updated checklist of the amphibians and reptiles of Nayarit, Mexico with conservation status and comparison with adjoining States

Herein, we present an updated list of the species of amphibians and reptiles that inhabit Nayarit, Mexico. In the years since the publication of a previous list in 2016, threats to amphibians and reptiles in Nayarit have continued unabated and efforts to more fully catalogue the richness of Nayarit’s herpetofauna have continued. Nayarit harbours 162 native species of amphibians and reptiles, representing 35 families and 85 genera. These include 37 species of amphibians (35 anurans and two salamanders) and 125 species of reptiles (one crocodile, 44 lizards, 69 snakes and 11 turtles). Of the amphibian and reptile species in Nayarit, 102 are endemic to Mexico and two endemic to Nayarit. The ecoregion with the highest richness of amphibians and reptiles in Nayarit is the Trans-Mexican Volcanic Belt followed closely by the Sierra Madre Occidental and then the Sierra Madre del Sur, the Pacific Lowlands and the Nayarit Islands. Just 5.8% of the species of amphibians and reptiles in Nayarit is IUCN-listed as Vulnerable, Endangered or Critically Endangered, 11.1% are placed in a protected category by SEMARNAT and nearly a third are categorised as high risk by the Environmental Vulnerability Score. The herpetofauna of Nayarit overlaps the most with Jalisco (88.9%). One of the main conclusions of our updated list of the amphibian and reptile species of Nayarit is that our understanding of the full complement of species is not complete, especially the reptiles.

Male flowers reveal the true identity of a new species of Hechtia (Bromeliaceae) from the Mexican state of Jalisco

A new species of Hechtia (Bromeliaceae, Hechtioideae) from the Mexican state of Jalisco and from the Pacific Lowlands biogeographical province is proposed as Hechtia carrilloi. Herbarium specimens of this new species were initially assigned to Hechtia santanae but after the study of living plants and fresh male flowers, we concluded that they differ in several features, including leaf surface (sparsely lepidote to glabrous vs. densely lepidote), flower size (4–5 mm long, 1–2 mm in diameter vs. 5–5.5 mm long, 3.8–4.2 mm in diameter), corolla shape (tubular vs. obconical), and anther color (maroon vs. reddish). A complete description based on female and male plants as well as fruits is provided. Likewise, photographs and illustrations showing diagnostic characters and habitat features are included. Additionally, an assessment of the conservation status of the new taxon based on the B criteria of the IUCN is presented.

Biogeographical affinities of the biota of the Tres Marías Islands, Mexico

Abstract The Tres Marías archipelago in the central Mexican Pacific is a protected area that has a complex geological history due to its tectonic setting. This study describes an integrative analysis of the biogeographical affinities of the biota inhabiting the islands. A biotic component analysis showed a close relationship between the islands and the Pacific Lowlands and Veracruzan biogeographical provinces, whereas a cladistic biogeographical analysis additionally showed a Nearctic affinity with the Sonoran biogeographical province. The biogeographical affinity patterns, based on the distribution of the sister group of each endemic species, revealed three distinct patterns: Neotropical, Sonoran-Neotropical and Nearctic-Neotropical. The study recognized that the Tres Marías Islands are a region of great biological complexity where the biota of the Pacific Lowlands and the Veracruzan provinces intersect, with a predominantly Neotropical affinity. In this biogeographical analysis, information on the biotic assemblage and the geological history of the Tres Marías Islands are integrated and discussed. The biotic assembly of the islands must have occurred via both vicariance and dispersal at different geological times, related to opening of the Gulf of California (Miocene–Pleistocene) as well as to periods of glaciation (Pleistocene).

Emotions and gendered experiences of livelihood migration: memos from Nicaragua and Guatemala

With increasingly difficult conditions for smallholder agricultural production, labor migration is an essential component of livelihoods for many rural families in the Global South. This migration is gendered and is often normalized as part of households’ livelihood portfolios. Yet it also can reproduce livelihood precarity and help maintain underlying structural inequalities. The role of labor migration as a livelihood strategy therefore requires continued research attention. Livelihood processes, including those connected to gendered labor migration, are infused with and shaped by a variety of emotions, including stress, longing, suffering, or contrastingly, aspiration, exhilaration, wellbeing, or happiness, that are experienced intersectionally. In this Viewpoint, we present our perspective that excluding analysis of emotional experience imperils comprehension of the drivers, motivations, and impacts of growing livelihood migration and other gendered livelihoods shifts. Emotions are core to migration decision-making, impact, and experience and therefore are central to any holistic understanding of the migration-livelihoods nexus. Paying attention to the role of emotion at the livelihood-migration nexus, where emotions often take center stage, is also a helpful entrée for taking both affect and intersectionality more seriously in the broader context of gendered livelihoods in general. We have developed this perspective while conducting fieldwork for research on labor migration and environmental change in Guatemala’s Pacific lowlands and Nicaragua’s northwest and draw upon that fieldwork to make our case.

Helmet Shape and Phylogeography of the Treehopper Membracis mexicana.

Membracis mexicana (Hemiptera: Membracidae) is distributed in four biogeographic provinces of Mexico. Field observations indicate that there are different forms of this species, but the distribution of the phenotype and the genetic variation of this species have not been clarified. The aim of this study was to quantify the phenotypic and genetic variation of M. mexicana and determine whether the configuration of biogeographic provinces impacts the distribution of this variation. To achieve this, we analyzed 307 photographs using 19 landmarks and geometric morphometrics to quantify the phenotypic variation in helmets. We sequenced five molecular markers for 205 individuals to describe the phylogeographic pattern. As a result, we identified three morphological configurations of the helmet of M. mexicana and two genetic lineages. The morphotypes are (1) a large and wide helmet with small dorsal spots, (2) a small and narrow helmet with large dorsal spots, and (3) a small and narrow helmet with small spots. Genetic lineages are distributed in southeast and western Mexico. The western lineage corresponds to two helmet morphotypes (1 and 2) and the southeast lineage to morphotype 3. We found that the larger helmets correspond to the western lineage and are distributed in Trans-Mexican Volcanic Belt and Pacific lowlands provinces, whereas the smallest helmets correspond to the southeast lineage and are present in the Veracruzan and Yucatan Peninsula provinces.

A new species of Caecilia Linnaeus, 1758 (Amphibia: Gymnophiona: Caeciliidae) from the Pacific lowlands of Colombia, with comments on the status of C. tenuissima Taylor, 1973.

We here describe a new species of the genus Caecilia from the Pacific lowlands of Colombia that was mistaken in previous literature as C. tenuissima, but which has more primary and secondary grooves than that species (among other differences). The description of Caecilia wilkinsoni sp. nov. restricts the known distribution of C. tenuissima to Guayaquil, Ecuador, re-establishing its status as an endemic species. We comment on the type locality of C. tenuissima, the current condition of its holotype, and on the distributions of the Caecilia that inhabit the Pacific region of Colombia.

Evolutionary biogeography of the Revillagigedo Archipelago, Mexico

ABSTRACT The biotic assembly of the Revillagigedo Archipelago, Mexico, was analysed under an evolutionary biogeographic framework. We undertook a parsimony analysis of endemicity with progressive character elimination of 194 plant and animal species, which allowed us to identify the archipelago as a complex area or node where Nearctic and Neotropical biotic components overlap. We undertook a cladistic biogeographic analysis using the phylogenetic information of 42 taxon-area cladograms, from which one general-area cladogram was obtained: (Revillagigedo, (Sonoran, (Baja California, (Veracruzan, Pacific Lowlands)))). These results suggest that the Revillagigedo Archipelago may be classified as a province, although we prefer to keep it as a district of the Pacific Lowlands province. We identified two cenocrons (temporally integrated set of taxa) that can be dated to the Pliocene–Pleistocene: one Nearctic that dispersed from the Baja California Peninsula, and another Neotropical where the species dispersed from the Pacific coast to the islands. The geological information and the general-area cladograms allowed us to propose a geobiotic scenario for the archipelago where the islands are probably the result of volcanism associated with the oceanic Mathematician Ridge, and the arrival of the cenocrons to the archipelago may have occurred during the Pliocene–Pleistocene, after the islands were available for colonisation.

A new Ophidion (Orchidaceae, Pleurothallidinae) from the Pacific lowlands of Colombia and the unresolved phylogenetic position of Phloeophila s.l.

A species new to science of a miniature orchid, endemic to the humid Pacific lowland, Municipality of Buenaventura (Valle del Cauca, Colombia), is described and illustrated. Ophidion erectilabrum sp. nov. is morphologically similar to O. alphonsianum, but the new species is recognized by the orbicular leaves (vs. elliptic), the erect inflorescence, longer than the leaves (vs. descending, shorter than the leaves), and the abruptly upward curved epichile (vs. flat). Because of the different proposals in the circumscription of Phloeophila s.l., we performed a new phylogenetic analysis to assess the most appropriate genus to place the new species, and discuss the phylogenetic position of Luerella, Ophidion, and Phloeophila based on all currently available data from nrITS and matK and recent studies using high-throughput sequencing. Although the three genera are supported as monophyletic groups, we recovered unresolved relationships and discordant topologies among them using only these two molecular markers. Therefore, we describe this species in Ophidion because of the morphological differences between Luerella and Phloeophila and because the grouping of Phloeophila s.l. lacks diagnostic features, and is yet to be supported by molecular analysis.

Molecular phylogenetic and taxonomic status of the large-eared desert shrew Notiosorex evotis (Eulipotyphla: Soricidae)

Abstract Notiosorex is the only genus of shrews in North America with particular adaptations for arid habitats such as deserts. Five species currently are recognized in the genus, one of which, Notiosorex evotis, lives in deciduous rain forest from northern Sinaloa to the state of Jalisco in México. Notiosorex evotis originally was described as a subspecies of N. crawfordi; however, it was recently proposed as a valid species based on a discriminant function analysis of craniodental characters. Morphological differentiation between N. evotis populations and sympatric occurrences with N. crawfordi in northern Sinaloa have been recognized. Here, we used a phylogenetic analysis of a mitochondrial gene (Cytb; 1,140 bp) and the nuclear beta fibrinogen intron 7 (β-fib I7; 385 bp), as well as cranial geometric morphometrics, to assess the taxonomic status of N. evotis. We found sequences of N. evotis forming two main subclades: one that includes the populations of the state of Sinaloa, the other including populations of Nayarit and Jalisco. The boundaries between the two groups seem to be related to the ecotonal cline between the Pacific Lowlands province and the Trans-Mexican Volcanic Belt province, which acts as a geographical barrier. The discriminant function analysis revealed clear differences in skull shape between the three species of Notiosorex to the northwest of its distribution. Considering these multiple lines of evidence from our data set, we confirm that N. evotis is a monotypic species. Our results suggest that geometric morphometrics can be used successfully to identify sibling species by shape, especially in groups where determination by craniodental measurements is not possible.

THE OCCURRENCE OF THE MILK FROG Trachycephalus typhonius (AMPHIBIA: HYLIDAE) IN THE CENTRAL VALLEY OF COSTA RICA

Trachycephalus typhonius is a common species in several habitat types, and it has a wide distribution from Mexico to southern Brazil and northern Argentina. In Costa Rica, it inhabits the Pacific lowlands and marginally in the San Juan River basin near the border with Nicaragua. However, their records in Costa Rica are limited. Here we report the presence of this frog in the Central Valley of Costa Rica at 1145 m elevation in the Tropical Premontane Moist forest. This record is the first for this life zone in Costa Rica, which could indicate that the species has expanded to new climatic environments. However, and although the species had not been reported in this locality, it is possible that it has a historical distribution here, but its populations have been affected by changes in land use.

In the Shadow of the Green Revolution: Constrained Spatial Imaginaries and Smallholder Farming in Guatemala’s Pacific Lowlands

Much smallholder farming currently exists side by side with large-scale, industrial agriculture, as an outcome of the Green Revolution unfolding in uneven and dualistic terms. In Guatemala’s Pacific lowlands, state incentives fuel expansion of industrial export agriculture. Large-scale sugarcane production has come to surround rural farming communities, where small-scale farmers grow maize and sesame with little state support. Drawing on a survey of nearly 200 households, seventeen in-depth interviews, and four focus groups in five communities during 2014 and 2015 in the Department of Retalhuleu, our research explores the realities and imaginaries of smallholders as they negotiate their incorporation into the Green Revolution. In the face of minuscule agricultural plots resulting in limited production, cycles of agrarian debt, vulnerability to drought, and emigration to the United States, smallholders paradoxically work hard to replicate “modern” Green Revolution approaches in their own parcels. We argue that the proximal, uneven expansion of modern technocentric agriculture, fueled by the model of the Green Revolution, has helped cultivate “constrained spatial imaginaries” among smallholders, in which ideas and desires around improved agricultural practices remain bound to accessing hybrid seeds, chemical inputs, and technical extension, despite the way the Green Revolution has been implicated in their ongoing marginalization.

(2847) Proposal to conserve the name Anthurium microspadix against A. porrectum (Araceae)

(2847) Proposal to conserve the name <i>Anthurium microspadix</i> against <i>A. porrectum</i> (<i>Araceae</i>)

Feral Animals, Rastrojo, and Dispossession: Images of the Afterlives of War in Bajo Atrato, Colombia

AbstractThis article examines the ruinous traces left by armed conflict in the villages of Afro‐Colombian rural peoples living in Bajo Atrato, a region located in the Colombian Pacific lowlands. Through a set of images that illustrate the way animals and plants participate in the decline of abandoned houses and fields, I argue that war is not just a phenomenon unfolding in particular places but rather a force producing such places. Attention to the lasting effects produced by rubble, resurgent forests, feral animals, and trees pocked from gunfire compels us to reconsider how to assess the environmental impacts of war.