Miguel Simó

Universidad de la República de Uruguay | UdelaR · Faculty of Sciences

Tutaibo carita Cajade sp. nov. and Tutaibo sam Cajade sp. nov. are described from Uruguay based on males and females. Illustrations of somatic and sexual characters and a species distribution map are provided. In addition, new records of Tutaibo velox (Keyserling, 1886) are provided. These findings represent the southernmost records for Tutaibo and...

A new species of Neonella Gertsch, 1936 is described from Uruguay: N. almita n. sp., which inhabits natural grasslands. Additionally, first records of N. acostae Rubio, Argañaraz & Gleiser, 2015, and new records of N. lubrica Galiano, 1988, N. minuta Galiano, 1965, and N. montana Galiano, 1988 are given. Illustrations of the habitus, sexual charact...

Dubiaranea magatama Cajade, Hagopián & Rodrigues n. sp. is described from Uruguay, and southern Brazil based on males and females from several types of native forests, and a potential distribution for this species is modeled. The predicted model for this species indicates a Pampean province and southern Atlantic Forest biome distribution. Three var...

Sarinda sombraluminosa Hagopián, Laborda & Simó sp. nov. and Sarinda contraluz Hagopián & Bustamante sp. nov. are described from Uruguay based on males and females. New records of Parafluda banksi Chickering, 1946 and Sarinda marcosi Piza, 1937 for the country are provided. Illustrations and electron micrographs of sexual characters, photographs of...

Agyneta hum Cajade, Rodrigues & Simó n. sp. and Agyneta unguiserrata Cajade n. sp. are described and illustrated from Brazil and Uruguay based on males and females. Males of A. hum differ from the related A. adami (Millidge 1991) by having apical and posterior pocket of paracymbium, presence of dorsal tibial apophysis and the shape and surface of t...

Typically, females and males are expected to have characteristic sexual strategies and patterns of size dimorphism, but these generalizations are subject to exceptions. The occurrence of atypical cases has been related to species or populations from environments under strong physical, ecological and/or social constraints. Allocosa marindia and Allo...

Grasslands are among the biggest and most bio-diverse ecosystems in the world and are critically endangered by the expansion of agricultural lands and urbanization. In Uruguay, grasslands from different ecoregions are suffering different rates of fragmentation and loss. Therefore, it is important to enhance the basic knowledge of grassland biodiver...

Pseudotyphistes deinceps Cajade n. sp. is described from Uruguay based on males and females. Illustrations of somatic and sexual characters and a distribution map of the species is provided. In addition, new records of Pseudotyphistes pennatus Brignoli, 1972 for the country are presented. Data of the natural history and conservation status of both...

Biodiversity loss is a global concern, and agriculture is one of the economic sectors responsible for this impact. The assessment of ecosystems under the influence of livestock production is essential for knowing their integrity and ability to provide ecosystem services. The aim of this investigation was to evaluate the application of LEAP/FAO guid...

A new species of Chelodesmidae is described from northern Uruguay, Sandalodesmus joachimadisi n. sp. The new species differs from other congeners by particular features of the gonopods. Sandalodesmus joachimadisi n. sp. belongs to the iguazuensis species group. Photographs of the new species, data on its natural history and a geographic distributio...

Grasslands are endangered habitats through the world. Among its threats, land-use change has been recognized as one of the most important drivers of biodiversity decline. Sustainable livestock farming can be important conserving grasslands and preserving their biodiversity, and particularly in Uruguay are extensive and are carried out based on natu...

The taxonomy and systematics of the subfamily Allocosinae are poorly known, especially in South America. In the last century, several species have been described in genera from other subfamilies or transferred to them creating great confusion in the knowledge of Allocosinae. In this study we propose the new genus, Abaycosa gen. nov. to contain two...

Arthropods inhabiting floodplains have to cope with regular cycles of wet and dry conditions. Allocosa senex and Allocosa marindia are two sympatric and synchronic sand‐dwelling wolf spiders that construct burrows along South American coasts and are subject to periodic floods. Our objective was to study tolerance to immersion and describe the behav...

The genus Mastophora Holmberg, 1876 is represented by 50 species that are distributed mainly in America and the Antilles. Males are much smaller than females and are not described in more than half of the known species of the genus. The high specificity of their diet (moths) and the technique which females use to capture their prey have been record...

1. Major floods of riparian and grassland habitats may lead to a shift in the availability of resources (e.g., food, space) that produces cascading effects on the organisms that rely on it. After flooding occurs, particularly in natural grasslands or agricultural fields, massive aggregative spider webs are occasionally observed. However, given it i...

The male of the wolf spider Paratrochosina amica Mello-Leitão (1941) is redescribed, and the female of this species is described for the first time. Additionally, we evaluate the phylogenetic position of P. amica using the mitochondrial genes cytochrome c oxidase subunit I (cox1), the 12S rRNA (12S) and 16S rRNA (16S), NADH deshydrogenase subunit I...

Sarinda marcosi Piza, 1937 is an ant-like jumping spider that shares its microhabitat with the carpenter ant Camponotus mus Roger, 1863 (Hymenoptera: Formicidae). The objectives of this study were to record S. marcosi from Uruguay, to describe the type of mimicry present in this species, and to determine the ant model it mimics and how closely it r...

The millipede species Oxidus gracilis (Polydesmida: Paradoxosomatidae) is recorded for the first time in Uruguay. This constitutes the first record of the Order Polydesmida and the family Paradoxosomatidae for the country. The species was found in synantropic environments. Data on its natural history and distribution in the country are included.

In previous studies, Uruguay has been considered a biogeographical crossroads. Paso Centurión and Sierra de Ríos in eastern Uruguay were recently entered into the National System of Protected Areas. The landscape is characterized by a mosaic of different ecosystems located in one of the dendrofloristic hotspots proposed for the country. The spiders...

The immune response can be costly. Studies in several arthropod species have indicated a trade-off between immunity and other life-history traits, including reproduction. In sexually dimorphic species in which females and males largely differ in their life history strategies and related energetic demands, we can expect to find sex differences in im...

Latica galeanoi, the sole species in a new genus within Gnaphosidae, is described from Uruguay and Argentina based on morphological, molecular and biogeographic data. The genus is sister to the rest of the Herpyllinae subfamily. The delimitation of this new genus is supported by various plesiomorphic and synapomorphic characters, which represents h...

Cannibalism is considered common among spiders. Nonsexual cannibalism might provide a significant foraging behavior for wolf spiders. To determine the type of cannibalism that influences the foraging behavior of Lycosa poliostoma (Lycosidae), we conducted experiments to test whether hunger level and territoriality affected the rate of cannibalism i...

Dispersal ability can enhance the probability of an organism surviving and reproducing, and affects the geographic structure of its genetic variability. Allocosa senex is a nocturnal sand-dwelling wolf spider strictly associated with oceanic, estuarine and freshwater sandy coast habitats of southern South America, including Uruguay, Brazil, and Arg...

De las 118 familias de arañas conocidas, la familia Salticidae es la que presenta mayor riqueza específica con un total de 636 géneros y 6089 especies descriptas (World Spider Catalog, 2018). A pesar de ello, sólo diez especies fueron citadas en el último catálogo de arañas de Uruguay (Capocasale & Pereira, 2003). Por tal motivo se considera que la...

Animals may build refuges to avoid predation, to communicate, to mate, and to protect against extreme temperatures, among other factors. Allocosa senex is a wolf spider that constructs burrows in the coastal sand dunes of South America. The distribution of A. senex includes beaches with different granulometry, which could affect burrow characterist...

Biological corridors are connections which link habitats in a regional scale, allowing the gene flow between populations. The Uruguay River comprises riverside and insular riparian forests along subtropical to temperate zones passing through different biogeographic provinces. The aim of this study was to characterise the spider fauna from the Urugu...

Allocosa senex (Mello-Leit˜ ao, 1945) is a sex role-reversed wolf spider that inhabits sandy water-margin environments of southern South America. Males are larger than females and dig deeper burrows. Females are the courting sex and they prefer to mate with males that build deep burrows, suggesting high selective pressures on male digging behavior....

The rice crop and associated ecosystems constitute a rich mosaic of habitats that preserve a rich biological diversity. Spiders are an abundant and successful group of natural predators that are considered efficient in the biocontrol of the major insect pests in agroecosystems. Spider diversity in different stages of the rice crop growth from easte...

Dissimilarity Matrix SIMPER Test

Among ctenid spiders, ctenines comprise the most diverse subfamily. In this study, a new genus of Cteninae, Spinoctenus, is proposed to include the type species S. yotoco, sp. nov. Ten new species are also described: S. escalerete, S. pericos, S. eberhardi, S. spinosus, S. stephaniae, S. nambi, S. florezi, S. tequendama, S. chocoensis and S. flammi...

La mirmecomorfia es un tipo de mimetismo en el cual algunos organismos imitan ciertas especies de hormigas, tanto en morfología, comportamiento y coloración. En la familia Salticidae, varios géneros presentan este tipo de mimetismo que les otorga ventajas para obtener su alimento y evitar la depredación. El objetivo de este estudio fue reportar la...

Natural history collections are essential tools for development in biological research. Since the nineteenth century, arachnological collections in the Neotropics have been collaborating to carry out research on spiders and human resource training. In many cases, they have been the starting point of several research fields and the first steps allow...

Dispersal strategies are essential for species survival. Animals need to move to search for food, to locate potential sexual partners, to find refuge and escape from predators, and to avoid inbreeding and local competition for resources. The degree of plasticity of those traits will determine the ability of the species or population to respond succ...

La lista de especies prioritarias para la conservación en Uruguay resulta un insumo imprescindible para la gestión de la biodiversidad a nivel nacional y regional. Actualmente esta lista contiene vertebrados, plantas vasculares y moluscos continentales, siendo estos últimos los únicos representantes de invertebrados. Los arácnidos son predadores “t...

Allocosa senex is distributed along the sandy coasts of Argentina, Brazil and Uruguay. Individuals are nocturnal and build burrows in the sand where they stay during the day and in winter of the Southern Hemisphere. Most studies of this species have been carried out at estuarine or oceanic beaches. A. senex faces an important environmental stress b...

Three species of the genus Allocosa Banks, 1900 from southern South America are redescribed: Allocosa alticeps (Mello-Leitão, 1944), A. brasiliensis (Petrunkevitch, 1910) and A. senex (Mello-Leitão, 1945). The female of A. senex is described for the first time and the species is revalidated. A new species, A. marindia sp. nov. from southern Uruguay...

La agroecología promueve la aplicación de conceptos y principios ecológicos al diseño y manejo de ecosistemas agrícolas sustentables. En este marco es necesario el estudio de grupos indicadores, como los artrópodos, que permitan hacer estimaciones de la diversidad y así evaluar los cambios que ocurren en los agroecosistemas a lo largo de su histori...

The spider genus Chrysometa Simon, 1895 comprises 138 species of small (3-5 mm) Neotropical orb-weavers spiders (Nogueira et al. 2011; World Spider Catalogue 2015) mainly associated with arboreal vegetation from intermediate to low altitude forests (Levi 1986). Males of Chrysometa differ from other tetragnathids by having the palpal tibial length a...

In northeastern Uruguay there are tabular hills, relicts of basaltic depositions occurred during the Mezosoic, wich present strata with different vegetation types. This range of hills constitute a biological corridor which connect riparian forest plains, wetlands, Atlantic Forest, Araucaria Forest, Parana Forest and, in the past, with Cerrado bioma...

The genus Eutichurus was created by Simon (1897) on the basis of three species from Brazil and Ecuador originally placed in the family Clubionidae. Lehtinen (1967) transferred the genus to Miturgidae and created the subfamily Eutichurinae, although the limitation of this taxon was not clear. Bonaldo (1994) defined this subfamily based on the Neotro...

Hersiliidae is reported for the first time for Uruguay. Data of natural history and distribution of Iviraiva pachyura are provided.

This is the first record for the species Iviraiva pachyura and for the family Hersiliidae in Uruguay. Data presented represent the southernmost record for the species. Figures of living specimens, copulatory organs and a description of the egg sac are provided. The distribution of the species is shown and discussed.

The invasive species Badumna longinqua and the family Desidae are recorded for the first time for Brazil. The spiders were collected in urban habitats of two cities from the state of Rio Grande do Sul in southern Brazil. Specimens and their webs were found in public parks, window frames and in a cemetery. The absence of this species along a nationa...

Allocosa brasiliensis is a sand-dwelling wolf spider considered a good bioindicator to evaluate the quality of coastal dune ecosystems from Uruguay. Habitat fragmentation and human activities have impacted and reduced the Southern Uruguayan coast during the last decades. The aim of the present study was to evaluate the density, surface activity and...

The fauna of opilionids of Marindia was studied. This locality on the southern coast of Uruguay has been modified by human activity over the last 65 years, though it still maintains relictual areas. Twenty pit fall traps were located at two sites with different degrees of alteration, and were revised every fifteen days over two years. Acanthopa- ch...

Phenology of epigeic spiders of a coastal zone from Southern Uruguay: a biannual study using pitfall traps. Of about 200 species of spiders indicated for Uruguay, little is known about their phenology. In this paper we analyze the temporal distribution of spider captures by pitfall traps in the sandy coastal strip of the Río de laPlata at Marindia,...

Harvestmen are a good taxon for biogeographic studies due to their low vagility and their dependence on environmental conditions which make most of them live in humid and shaded habitats. Current knowledge of the geographical distribution of Uruguayan opiliofauna suggests that no evident zoogeographic areas are present, mainly because of the appare...

Agroecosystems are populated by a great diversity and number of invertebrates that are often disturbed by agricultural practices and grazing. The arthropods are good indicators of the heterogeneity of the habitat, the biodiversity of the ecosystem and the stress conditions of the environment, therefore its use for environmental management can reduc...

The spider Latrodectus mirabilis (Holmberg, 1876) is commonly found in cereals crops of central Argentina. We studied its diet composition at the field and capture rate on leaf-cutting ants based on laboratory experiments. This study comprises the first approach that documents the diet of L. mirabilis in wheat and oat fields of central Argentina. W...

Summary Predators such as spiders are particularly vulnerable to habitat fragmentation and are considered good bio-indicators of nature conservation or habitat degradation. As occurs all around the globe, the Uruguayan coastal sand dunes have been drastically diminished and fragmented, and seriously affected by human modifications such as urbanizat...

This study provides new records, geographical distribution extensions and a checklist of the current ctenids species in Co-lombia based on the review of four arachnological collections and published literature. A total of 15 new records for Cteni-dae in Colombia are reported; nine of these species are new records for the country and the distributio...

Badumna longinqua (L. Koch 1867) is a medium-sized spider native from Australia. Due to its synanthropic habitat, this spider expanded their range distribution, reaching Germany, Japan, New Zealand, Uruguay and USA. We found specimens of this species in different localities from Buenos Aires Province, Argentina. Therefore, we report the first recor...

Two new species of Mesabolivar González-Sponga are described, M. charrua sp. nov. and M. uruguayensis sp. nov. the male of M. tandilicus Mello-Leitão is redescribed. Notes on the natural history of the presented species are presented.

The male of Latonigena auricomis Simon, 1893 is described for the first time and the female is redescribed. New records are provided for Argentina, Brazil and Uruguay. Notes on the natural history and a potential distribution model of the species are presented in the Neotropical Region.

This study provides the first accurate records of Latrodectus geometricus C. L. Koch, 1841 for Uruguay and extends the known distribution of this species to the Southeastern region of South America. Data and figures of the genitalic morphology for the recognition of the species and natural history in this country are indicated. In Uruguay L. geomet...

Two new species of Mesabolivar González-Sponga are described, M. charrua sp. nov. and M. uruguayensis sp. nov. the male of M. tandilicus Mello-Leitão is redescribed. Notes on the natural history of the presented species are presented.

This is the first record for the species Deinopis amica and for the family Deinopidae in Uruguay. The present study expands the known distribution of the species to the lower Uruguay River. Data on natural history of the species is provided.

La araña invasora Badumna longinqua (L. Koch, 1867) (Desidae) se encuentra asociada a troncos de árboles, paredes de roca, y es muy común en hábitats sinantrópicos como rincones de ventanas, grietas de paredes, dentro y fuera de las casas y parque urbanos. Su tela consta de un refugio y numerosas capas, que se irradian en varios ángulos. Nativa de...

Los modelos obtenidos registraron valores del área bajo la curva ROC (AUC) que oscilaron entre 0.987 a 0.996, lo que indica un alto grado de predicción de los mismos. P. boliviensis, A. bogotensis y C. coccineus mostraron una distribución potencial amplia, preferentemente abarcando la costa caribeña y el pacífico sur. A diferencia de las anteriores...

Spiders are common generalist predators in terrestrial ecosystems, broadly used in diversity studies. The landscape of extensive areas of Uruguay was transformed in a mosaic of patches between natural habitats and agroecosystems. What level of change in the spider community could we expect if these areas are situated near from one another? What per...

Allocosa brasiliensis and Allocosa alticeps are two burrowing wolf spiders that inhabit Uruguayan sandy coasts. Male efficient digging is necessary because copulation and oviposition occur inside their burrows. We examined burrow distribution, density and temperature variation according to burrow depth. Adult burrows were more frequent at the slope...

Phoneutria bahiensis Simó & Brescovit, 2001 is a large ctenid spider inhabiting the states of Bahia and Espírito Santo, Brazil. Considering that it is probably endemic, this species was included in the Brazilian red book of threatened species. Here, we predict the distribution range of P. bahiensis using 19 bioclimatic variables in the model design...

In Uruguay, Badumna longinqua is an invasive species arising from Australia. Phoresy by human activities and strong adaptation to synantropic sites have been the main factors that have contributed to the dispersal of this species to other countries. In this study, we analysed the dispersion of B. longinqua in Uruguay using voucher specimens deposit...

Allocosa brasiliensis is a wolf spider that constructs burrows along the coastal sand dunes of Uruguay. They are medium-sized nocturnal spiders with whitish coloration that turns them cryptic with their sandy habitat. The species shows a reversal in both sex roles and sexual size dimorphism expected for spiders, being the first case reported in Ara...

Environments where prey availability is scarce or highly variable have been reported as potential settings for the occurrence of paternal investment and sex-role reversal (choosy males and competitive, courting females). Allocosa brasiliensis (Petrunkevitch 1910) and Allocosa alticeps (Mello-Leita˜o 1944) are two sand-dwelling wolf spiders that con...

The copulatory organs of the cryptic species Lycosa thorelli and Lycosa carbonelli are studied and are shown to exhibit some differences. The morphology of the epigynum, vulva and palpal organs of L. carbonelli are here described for the first time. Additional morphological data of these species are provided and the specific diagnosis reformulated....

This study provides new records, geographical distribution extensions and a checklist of the current ctenids species in Co-lombia based on the review of four arachnological collections and published literature. A total of 15 new records for Cteni-dae in Colombia are reported; nine of these species are new records for the country and the distributio...

Holocnemus pluchei y Spermophora senoculata fueron halladas en construcciones humanas en cuatro localidades de Uruguay y una de Argentina. Estos son los primeros registros para Sudamérica de estas dos especies sinantrópicas.

The occurrence, frequency and spatial-temporal variation of the epigeic fauna of the sandy coast of the Río de la Plata in Marindia (Canelones, Uruguay) were studied using pitfall traps. Ten traps were placed in the first, partially mobile sand dunes (Southern zone) 80 m away from the wave pointbreak, and another 10 traps were placed 180 m from the...