Guillermo Ibarra-Núñez

• Researcher at El Colegio de la Frontera Sur

Background Members of the genus Cupiennius Simon, 1891 are categorized as wandering spiders and are part of the family Trechaleidae. The genomics and proteomics of Cupiennius spiders from North America remain uncharacterized. The present study explores for the first time molecular data from the endemic species Cupiennius chiapanensis Medina, 2006,...

Falconina cafeterasp. nov. (Araneae, Corinnidae) is described based on specimens of both sexes. Specimens were collected in shaded coffee agro-ecosystems and in a suburban cacao orchard in Chiapas, Mexico. This new species is the first Falconina recorded from Mexico and the northernmost species of the genus in continental America, with the exceptio...

Because spiders have a great variety of strategies to capture their prey they have been grouped into ecological guilds. The objective of this study was to determine the composition and structure of spider communities in coffee plantations with different management systems (monoculture and polyculture shade), through their classification into ecolog...

This study focuses on species richness, abundance, diversity, and seasonal variation of spiders in two coffee plantations with different crop management and a portion of tropical forest in two municipalities of La Costa region of Oaxaca, Mexico, using manual collection, foliage beating and pitfall traps. We collected 2,210 spiders belonging to 35 f...

The spider genus Strotarchus Simon, 1888 includes 18 extant species from the American continent (12 from Mexico). Additionally, two fossil species have been described for this genus, Strotarchus paradoxus (Petrunkevitch, 1963) from Mexican amber (Chiapas), and Strotarchus heidti Wunderlich, 1988 from Dominican Republic amber. From two pieces of amb...

Background: Phonotimpus pennimani (Araneae, Phrurolithidae) is a small-sized (3-5 mm) spider endemic to the Tacaná volcano in Chiapas, Mexico, where it is found in soil litter of cloud forests and coffee plantations. Its venom composition has so far not been investigated, partly because it is not a species of medical significance. However, it does...

An organism's morphological features can determine the type of prey they consume due to adaptive advantages in capturing them, for example, the shape and length of the bill in birds. Hummingbirds have been considered specialists in nectar consumption. However, they have been documented to also be important insectivores in ecosystems. In this study,...

The American genus Phonotimpus Gertsch & Davis, 1940 (Araneae, Phrurolithidae) was described on the basis of two species from northern Mexico. Recently, four species were described from Central and South Mexico and one species was transferred to this genus. Here we describe the males of Phonotimpus separatus Gertsch & Davis (the type species) and P...

Volant vertebrate insectivores, including birds and bats, can be important regulators of herbivores in forests and agro-ecosystems. Their effects can be realized directly through predation and indirectly via intraguild predation. This paper examines data from bird and bat exclosures in coffee farms in Chiapas, Mexico in order to determine their eff...

Phonotimpus padillai sp. nov. is described on the basis of morphological characteristics of both sexes: males are easily distinguished by the shape of the embolus and females by the shape of the copulatory openings. Additionally, Gosiphrurus schulzefenai Chamberlin & Ivie, 1936 is transferred to the genus Phonotimpus Gertsch & Davis, 1940, based on...

A new genus and species of spider (Araneae, Linyphiidae, Erigoninae) from a tropical montane cloud forest of Mexico is described from both male and female specimens, Xim trenzado gen. et sp. nov. A phylogenetic parsimony analysis situates Xim gen. nov. as a distinct genus among the distal Erigoninae. Xim gen. nov. is sister to a clade including Cer...

Four new species of the spider genus Novalena Chamberlin & Ivie, 1942 are described: N. bola sp. nov., N. mayae sp. nov., N. padillai sp. nov., and N. zootaxa sp. nov. All species were collected in montane forests in Chiapas, Mexico, and three of them occur in sympatry across their distribution range.

Se analizó la variación espacial de las comunidades de arañas del suelo y sotobosque asociadas a tres localidades con bosque mesófilo de montaña (BMM) de la Sierra Madre de Chiapas. Los resultados demuestran una marcada segregación entre los diferentes estratos y localidades. El estrato del suelo fue más heterogéneo que el del sotobosque, contrario...

We carried out an intensive and systematized sampling of the spider fauna of the tropical mountain cloud forest (TMCF) in El Triunfo Biosphere Reserve, Chiapas, Mexico, in order to analyze their composition, species richness, abundance, and proportion of undescribed species, and to compare these results with those found in other TMCFs. We sampled t...

Se estudió el comportamiento depredador de dos especies de arañas del género Phonotimpus (Araneae: Phrurolithidae) frente a cuatro tipos diferentes de presas potenciales (un Collembola, dos Hemiptera y un Psocoptera). Estas arañas habitan en la hojarasca del suelo de un bosque de niebla y de un cafetal en Chiapas, México. No existen estudios previo...

The genus Phonotimpus Gertsch & Davis, 1940 includes four species all known only from Mexico (World Spider Catalog 2018). P. separatus and P. eutypus were described by Gertsch & Davis (1940) from San Luis Potosí and from Nuevo León, respectively. Phonotimpus pennimani and P. talquian, described by Chamé-Vázquez, Ibarra-Núñez & Jiménez (2018), are t...

Wirada Keyserling, 1886 is one of the smallest genera of Theridiidae with only five South American species (World Spider Catalog 2018). Keyserling (1886) described first Wirada punctata (male) from Peru. Simon (1895) described W. rugithorax and W. tovarensis (males) from Venezuela, but Levi (1963) synonymized W. rugithorax with W. punctata. Later,...

El objetivo del presente trabajo fue conocer la distribución de las especies de Passalidae en un gradiente altitudinal en el Soconusco y relacionar la disponibilidad y características de la madera muerta con la riqueza y abundancia de pasálidos. Se seleccionaron nueve sitios con diferente altura sobre el nivel del mar (10-3000 m) y se usaron cinco...

The female of Phonotimpus separatus Gertsch & Davis (the type species of the genus) is redescribed from a specimen collected at the type locality, and two new species of Phonotimpus from Mexico are described: P. pennimani sp. nov. and P. talquian sp. nov. A more detailed description of P. separatus is provided to better distinguish them from relate...

New records of Hibana futilis (Banks, 1898) (adult female), Marpissa pikei (Peckham & Peckham, 1888) (adult male), Metacyrba punctata (Peckham & Peckham, 1894) (juveniles) and Paraphidippus fartilis (Peckham & Peckham, 1888) (adult female) from Jalisco state are provided. Marpissa pikei is a new record from Mexico

New records of Hibana futilis (Banks, 1898) (adult female), Marpissa pikei (Peckham & Peckham, 1888) (adult male), Metacyrba punctata (Peckham & Peckham, 1894) (juveniles) and Paraphidippus fartilis (Peckham & Peckham, 1888) (adult female) from Jalisco state are provided. Marpissa pikei is a new record from Mexico.

Cloud forests have high ecological complexity, but their reduced area and exploitation by human communities, make them one of the most endangered ecosystems in Mexico. The spider assemblages of a cloud forest reserve in Chiapas, Mexico, were studied to analyze influence of environmental variables (forest stand structure, temperature and relative hu...

A field survey was conducted in Ataulfo mango (Mangifera indica L.) orchards in Chiapas, Mexico, with the objective of determining the natural enemies of the Frankliniella complex species (Thysanoptera: Thripidae). Seven species of this genus feed and reproduce in large numbers during the mango flowering. Two representative orchards were selected:...

Diversity and temporal variation of arboreal spiders were studied in 2 cocoa plantations with different agronomic management in Chiapas, Mexico. Sampling was made by direct visual collecting on cocoa trees randomly selected. The collected specimens (8 394) represent 28 families, 66 genera and 89 morphospecies, with 57 of these identified to species...

A new species of the spider genus Taczanowskia, T. gustavoi n. sp. is described from Chiapas, Mexico. This finding extends the distribution of Taczanowskia species, hitherto known only from South America to Southern Mexico. T. gustavoi n. sp. can be differentiated from all other species in this genus by having more than six tubercles in the dorsum...

Frugivorous are one of the main diaspore dispersers in tropical ecosystems, particularly in open areas and sites in the early stages of ecological succession. Frugivorous bat species respond differentially to habitat modification, and in the context of their diaspore dispersal functions it is important to understand species' ecological requirements...

Spiders can contribute to control of pest insects. Web-weaver spiders are common in many agroecosystems and, being sedentary, they are adequate for this type of studies. This paper deals with prey selection by four species of spiders, two orb-weavers (OW) and two cob-weavers (CW) and differences in diets, among species and among guilds, were analyz...

We evaluated the spider diversity of a tropical montane cloud forest understory in two nearby sites with different degree of human disturbance at the Biosphere Reserve Volcán Tacaná, Chiapas, Mexico. The study was conducted over a 24days period distributed in 6months in 2009, covering dry and rainy seasons. A total of 8,370 spiders (1,208 adults an...

Las arañas pueden contribuir al control de los insectos plaga. En muchos agroecosistemas son comunes las arañas que tejen redes para capturar a sus presas y siendo sedentarias, son ideales para este tipo de estudios. Se estudió la selección de presas por cuatro especies de arañas, dos tejedoras orbiculares (TO) y dos tejedoras irregulares (TI), y s...

A spider inventory from forest floor and understory in 2 sites of the cloud montane forest of the Biosphere Reserve Volcán Tacaná, Chiapas was undertaken. Soil spiders were collected using pitfall traps and processing litter in Berlese funnels; understory spiders were captured by hand collecting, sweeping, beating, and with shelter traps. Collected...

A spider inventory from forest floor and understory in 2 sites of the cloud montane forest of the Biosphere Reserve Volcán Tacaná, Chiapas was undertaken. Soil spiders were collected using pitfall traps and processing litter in Berlese funnels; understory spiders were captured by hand collecting, sweeping, beating, and with shelter traps. Collected...

Resumen - Se analizaron 1,300 registros taxonómicos de Passalidae, lo cual corrobora la presencia de 47 especies, 18 géneros y dos tribus de la subfamilia Passalinae. No obstante, esto representa el 83% de la fauna estimada para el estado de Chiapas, por lo que el inventario puede completarse durante los próximos años. Se determinó que existen zona...

Coffee agroforests may be structurally and floristically complex and may contain a significant fraction of species from biodiverse and threatened tropical montane forest biotas; hence, understanding the dynamics of tropical forest biodiversity in coffee agroecosystems has emerged as a centrally important area of tropical conservation biology resear...

Field observations of Homalometa chiriqui (Araneae, Tetragnathidae), a common habitant in coffee plantations in Chiapas, México, provide biological information on this poorly known species. Collection data revealed several generations per year. The web architecture and microhabitat selection of young juveniles differ from those of older juveniles a...

Se establece la sinonimia entre tres especies de arañas linífidas del género Frontinella F. O. Pickard-Cambridge 1902, con base en datos de campo sobre la asociación entre machos y hembras, registros de apareamientos, y datos de la morfología de especimenes recientemente colectados. Se concluye que F. caudata Gertsch & Davis 1946 y F. lepidula Gert...

Eighty parcels producing cacao in four areas at the Soconusco region, Chiapas, Mexico, were studied in order to analyze the arboreal diversity. The diversity indexes of Shannon and Simpson, and the similarity indexes of Sørensen and Morisita-Horn were applied. Eighty sample sites, 30×30m each, were established and density, riches, and diameter at b...

SUMMARY Eighty parcels producing cacao in four areas at the Soconusco region, Chiapas, Mexico, were studied in order to analyze the ar- boreal diversity. The diversity indexes of Shannon and Simpson, and the similarity indexes of Sørensen and Morisita-Horn were applied. Eighty sample sites, 30×30m each, were established and density, riches, and dia...

Differences in alpha and beta bat diversity among montane rainforest and five shaded coffee plantations under different management regimes, as well as some environmental factors and vegetation parameters influencing bat richness, were evaluated for the first time in southeastern Chiapas, Mexico. In each site, bats were captured every 2 months from...

This paper presents an assessment of spider diversity in a complex landscape of southern Mexico. Eighteen different habitats were identified, measured and mapped across this fragmented landscape. Habitat types were characterized by measuring various features, including number of plant forms, tree cover and litter depth. Each month from February to...

This paper presents an assessment of spider diversity in a complex landscape of southern Mexico. Eighteen different habitats were identified, measured and mapped across this fragmented landscape. Habitat types were characterized by measuring various features, including number of plant forms, tree cover and litter depth. Each month from February to...

It is commonly thought that diverse agroecosystems are less prone to pest outbreaks because they support a high diversity of natural enemies. The idea that diversity stabilizes functional properties of communities to environmental perturbation is formalized in the ecological literature as the ''insurance hypothesis.'' Recently this hypothesis has b...

The role of Azteca sp. ants as potential biological control agents was studied in an organic coffee farm in Chiapas, Mexico. Individual larvae of Pieris rapae were placed on trees with artificially enhanced ant activity and both time to disappearance of the larvae and ant activity were recorded. There was a general negative relationship between tim...

This study focuses on the predatory capacity of four sympatric species of web- building spiders that inhabit coffee plantations in Southern Mexico: Gasteracantha cancriformis, Cyclosa caroli, and the morphologically similar species pair Leucauge mariana and L. venusta which were considered as one species group. The retention capabilities of the web...

A census of the prey captured by seven common web-building spiders (Cyclosacaroli, Gasteracantha cancriformis, Leucauge mariana, L. venusta, Anelosimus jucundus, Achaearanea tesselata, and an undetermined species of Linyphiidae) and two dominant ponerine ant species (Ectatomma ruidum and E. tuberculatum) was carried out over a two-year period in di...

We report here the first case of queen dimorphism in a ponerine ant species. A total of 550 colonies of the Neotropical ponerine ant Ectatomma ruidum, from two natural populations in southeastern Mexico, were investigated for polymorphism and reproductive function within the queen caste. The distribution of different morphological traits (head and...