Miguel Á. García-Martínez

New Ant Species (Hymenoptera: Formicidae) Records for Veracruz State and Mexico

Abstract. To contribute to the knowledge of the myrmecofauna of Mexico and Veracruz State, we conducted collections in soil, litter, and herbaceous-shrubby vegetation using different capture techniques. The specimens were deposited in the Entomological Collection of the Instituto de Ecología (Xalapa, Veracruz, Mexico). We report for the first time the presence of 21 species and one subspecies for Veracruz State, of which six are new records for Mexico. The number of species known from Mexico increased to 978 and from Veracruz to 331, suggesting that although this state is one of the most studied, its inventory of species is not yet fully known.

An Ornamental Heliconias Crop as a Reservoir of the Native Myrmecofauna: A case of Tropical Horticulture in Central Veracruz, Mexico

Abstract. Currently there is an increase in tropical crops dedicated to ornamental horticulture. This study is the first assessment of the role of a Heliconia spp. ornamental plant cultivation in Mexico as habitat for insect biodiversity conservation, using ant assemblages as bioindicators. A total of 9,022 ant workers belonging to seven subfamilies, 14 tribes, 27 genera, and 55 species was captured. Conversion of native vegetation to tropical ornamental agriculture affects the richness, diversity and dominance of ants, but not assemblages’ composition. The importance of species composition as a predictor parameter of functional changes in the landscape is highlighted.

Value of Riparian Vegetation Remnants for Leaf-Litter Ants (Hymenoptera: Formicidae) in a Human-Dominated Landscape in Central Veracruz, Mexico

ABSTRACT Riparian remnants are linear strips of vegetation immediately adjacent to rivers that may act as refuges for biodiversity, depending on their habitat quality. In this study, we evaluated the role of riparian remnants in contributing to the diversity of leaf-litter ants by determining the relationship between ant diversity and several riparian habitat characteristics within a human-dominated landscape in Veracruz, Mexico. Sampling was carried out in 2012 during both dry and rainy seasons at 12 transects 100 m in length, where 10 leaf-litter samples were collected along each transect and processed with Berlese-Tullgren funnels and Winkler sacks. A total of 8,684 individuals belonging to 53 species, 22 genera, and seven subfamilies were collected. The observed mean alpha diversity accounted for 34.4% of the total species recorded and beta diversity for 65.6%. Species richness and composition were significantly related to litter-layer depth and soil compaction, which could limit the distribution of ant species depending on their nesting, feeding, and foraging habits. Riparian remnants can contribute toward the conservation of ant assemblages and likely other invertebrate communities that are threatened by anthropogenic pressures. In human-dominated landscapes where remnants of riparian vegetation give refuge to a diverse array of myrmecofauna, the protection of the few remaining and well-preserved riparian sites is essential for the long-term maintenance of biodiversity.

Alpha Diversity of the Myrmecofauna of the Natural Protected Area Metlac from Fortin, Veracruz, Mexico

Abstract. Although the State of Veracruz is a megadiverse entity, it has the highest annual deforestation rates. Protected natural areas are considered strategic to preserve local biodiversity. In this paper, composition and alpha diversity of ant assemblages were analyzed in the natural protected area ‘Metlac’ near Fortin, Veracruz, Mexico. Sampling was conducted at four transects using baited pitfall traps and hand-collection. In total 3,204 ant workers belonging to 36 species, 21 genera, 12 tribes, and seven subfamilies were collected. The average alpha diversity was 16 species and no significant differences between recorded richness in each transect were found. Average sampling completeness was above 80%. Locally, Solenopsis geminata and Nylanderia steinheili dominate the epigeous and shrub strata due probably to their biological, behavioral and ecological plasticity that allows them to easily adapt to disturbed environments. This paper shows that for the small area sampled, the relict of tropical semi-evergreen forest is of great biological value despite heavy human intervention and the space-geographic context in which it is found.

The surrounding landscape influences the diversity of leaf-litter ants in riparian cloud forest remnants

Riparian vegetation is a distinctive and ecologically important element of landscapes worldwide. However, the relative influence of the surrounding landscape on the conservation of the biodiversity of riparian remnants in human-modified tropical landscapes is poorly understood. We studied the surrounding landscape to evaluate its influence on leaf-litter-ant alpha and beta diversity in riparian remnants in the tropical montane cloud forest region of central Veracruz, Mexico. Sampling was carried out in 12 sites with riparian vegetation during both rainy (2011) and dry (2012) seasons. Ten leaf-litter samples were collected along a 100-m transect per site and processed with Berlese-Tullgren funnels and Winkler sacks. Using remotely-sensed and ground-collected data, we characterized the landscape around each site according to nine land cover types and computed metrics of landscape composition and configuration. We collected a total of 8,684 ant individuals belonging to 53 species, 22 genera, 11 tribes, and 7 subfamilies. Species richness and the diversity of Shannon and Simpson increased significantly in remnants immersed in landscapes with a high percentage of riparian land cover and a low percentage of land covers with areas reforested with Pinus, cattle pastures, and human settlements and infrastructure. The composition of ant assemblages was a function of the percentage of riparian land cover in the landscape. This study found evidence that leaf-litter ants, a highly specialized guild of arthropods, are mainly impacted by landscape composition and the configuration of the focal remnant. Maintaining or improving the surrounding landscape quality of riparian vegetation remnants can stimulate the movement of biodiversity among forest and riparian remnants and foster the provision of ecosystem services by these ecosystems. Effective outcomes may be achieved by considering scientific knowledge during the early stages of riparian policy formulation, in addition to integrating riparian management strategies with broader environmental planning instruments.

Myrmecofauna (Hymenoptera: Formicidae) Response to Habitat Characteristics of Tropical Montane Cloud Forests in Central Veracruz, Mexico

Abstract Tropical montane cloud forests are characterized by a persistent cloud cover at the vegetation level. In central Veracruz, Mexico, these forests are found distributed in several small fragments with differing degrees of disturbance. In this changing ecosystem, the use of indicator groups has been proposed to assess disturbance effects on biodiversity. Ants may serve as bioindicators in various contexts, as they are social insects that have a high response capacity to environmental stimuli. In this study, the relationship of several environmental characteristics to ant diversity was measured in 5 fragments of tropical montane cloud forest in central Veracruz. In total, 5,270 individuals belonging to 75 species, 29 genera, 13 tribes, and 8 subfamilies were collected. The richness, diversity, and evenness increased significantly as a function of the structural complexity of the vegetation. In terms of composition and structure, the assemblages showed high heterogeneity between fragments. The similarity analyses showed high species complementarity between fragments, with a large proportion of unique species to each fragment. A high rate of species turnover is likely due to fragment isolation and its subsequent influence on habitat quality. However, the results demonstrated that overall, the remaining fragments of tropical montane cloud forest sheltered a large ant richness and diversity. In consideration of the observed habitat disturbances, it is necessary to implement measures that would allow for the conservation of the remaining fragments of cloud forest, as they represent an important reservoir of ant species and likely of other organisms as well.

Variación Temporal y Espacial de la Abundancia del Picudo Negro (Rynchophorus palmarum L., Coleoptera: Curculionidae) en Cultivos de Palmas Ornamentales del Centro de Veracruz, México

Resumen. Rhynchonphorus palmarum es una plaga importante en los cultivos de palmas de América puesto que es el vector del nematodo Bursaphelenchus cocophilus causante de la enfermedad del anillo rojo. Debido a que en el centro de Veracruz, México el cultivo de palmas ornamentales es económicamente importante, en este trabajo se analizó su abundancia temporal y espacial. Se reporta por primera vez para el Estado de Veracruz la presencia de R. palmarum asociado a diferentes hospederos. Se encontró que este escarabajo es significativamente abundante en la época lluviosa, lo cual coincide con la sincronía existente entre el ciclo biológico de este escarabajo y las estaciones del año en la región. Se encontró un efecto significativo de la abundancia de Whashingtonia robusta, Livistonona australis, y Dypsis lutescens, con la abundancia de R. palmarum. Nuestros resultados sugieren una preferencia de este insecto por hospedar en Washintonia robusta.

Myrmecofauna from Three Ornamental Agroecosystems with Different Management and a Forest Remnant in Ixtaczoquitlán, Veracruz, Mexico

Abstract. Ornamental horticulture is the commercial exploitation of fresh or preserved species that satisfy the visual tastes of consumers. This report compares the alpha and beta diversity associated with the myrmecofauna of ornamental crops of zingiberaceae, heliconias, and palms with different agricultural management practices and a remnant of forest in Ixtaczoquitlán, Veracruz, Mexico. A total of 965 ant workers belonging to 37 species, 25 genera, 16 tribes, and seven subfamilies was collected. Richness, diversity and evenness of species decreased significantly as the degree of management and agricultural intensification increased. The myrmecofauna composition from the forest was significantly different from that found in the three ornamental crops. The impact of ornamental horticulture on biodiversity may be due to farm management. Excessive use of agrochemicals generates local loss of species diversity. Ornamental crops with low intensification of agricultural management could represent a habitat that offers resources and conditions to different ant guilds and other invertebrates.

Importance of Nesting Resources and Soil Conditions for the Recovery of Ant Diversity During Secondary Succession in a Tropical Rainforest

The secondary succession of tropical rainforest in abandoned agricultural fields modifies components of species diversity and processes of species colonization and replacement. In general, knowledge on invertebrate reassembly is lacking, even though invertebrate assemblages directly influence the maturation of forests. Ants are especially useful for testing hypotheses about the effects of resource diversity and microhabitat conditions. We experimentally assessed the effects of different successional stages on nest colonization. Then, we assessed whether nesting resources and microhabitat conditions (i.e., abiotic conditions) are potential mechanisms that influence the colonization pattern of twig-dwelling ants along a natural chronosequence for 1 year in the Lacandon region, Mexico. We found that ant species richness in twigs is correlated with total species found in leaf litter. The nest occupancy increased as succession progressed, but species richness did not change. Nests occupation increased to greater artificial nesting resource decomposition rates and lower soil pH. Meanwhile, species richness was increased only with lower soil compaction. Species composition changes among successional categories; the changes were greater with greater soil compaction and soil pH. The diversity of nesting resources did not drive twig-dwelling ant assembly. We conclude that the natural maturation of tropical forest enables greater colonization of twig-dwelling ants, but recovery of the species composition of assemblages after 30 years is incomplete, although it shows a recovery trend.

The Fruit Fly Lure CeraTrap: An Effective Tool for the Study of the Arboreal Ant Fauna (Hymenoptera: Formicidae)

Abstract Despite preliminary reports of ants trapped in food-baited fruit fly traps, little is known regarding the identity of the myrmecofauna that can be sampled using this technique. This study aimed to examine the inventory completeness, activity and species occurrence of canopy ant assemblages collected in baited traps used for monitoring fruit flies in different fruit orchards in central Veracruz, Mexico. The trap models used in the sampling were Multilure, McPhail glass, and 500 ml blue polyethylene bottles. Three commercial fruit fly food attractants (CeraTrap, Captor + Borax, and BioLure) and two grape juice products (Jumex grape juice and Tang) were used as baits for sampling. In total 3,626 ant workers belonging to 54 species, 19 genera, 10 tribes, and 5 subfamilies were collected. Among the five food attractants used in this study, CeraTrap recorded a markedly higher inventory completeness, ant activity and species occurrence per trap. This study reports for the first time the use of CeraTrap, as a promising and effective food attractant for collecting the foraging ants in the canopy of agroecosystems, which may be applicable to other habitats such as natural forests, mangroves, or agricultural settings such as coffee plantations.