Cupiennius spiders (Trechaleidae) from southern Mexico: DNA barcoding, venomics, and biological effect.

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, and also presents new data for Cupiennius salei (Keyserling, 1878), both collected in southern Mexico. Methods: In total, 88 Cupiennius specimens were collected from southern Mexico and morphologically identified. DNA was extracted and the mitochondrial COI fragment was amplified. COI sequences were analyzed, and a phylogenetic tree was inferred for species from the Americas. Genetic diversity was analyzed using haplotype networks and gene distances. Venom was obtained from C. chiapanensis and C. salei by electrostimulation. The venom was separated by HPLC, visualized using SDS-PAGE, and quantified for use in toxicity bioassays in mice and insects. Results: Analysis of COI sequences from C. chiapanensis showed 94% identity with C. salei, while C. salei exhibited 94-97% identity with sequences from Central and South American conspecifics. The venom from C. chiapanensis exhibited toxic activity against crickets. Venoms from C. chiapanensis and C. salei caused death in Anastrepha obliqua flies. Analysis of venom fractions from C. salei and C. chiapanensis revealed molecular masses of a similar size as some previously reported toxins and neurotoxic components. We determined the amino acid sequences of ChiaTx1 and ChiaTx2, toxins that are reported here for the first time and which showed toxicity against mice and insects. Conclusion: Our work is the first to report COI-based DNA barcoding sequences from southern Mexican Cupiennius spiders. Compounds with toxic activity were identified in venom from both species.

Cupiennius spiders (Trechaleidae) from southern Mexico: DNA barcoding, venomics, and biological effect

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, and also presents new data for Cupiennius salei (Keyserling, 1878), both collected in southern Mexico. Methods: In total, 88 Cupiennius specimens were collected from southern Mexico and morphologically identified. DNA was extracted and the mitochondrial COI fragment was amplified. COI sequences were analyzed, and a phylogenetic tree was inferred for species from the Americas. Genetic diversity was analyzed using haplotype networks and gene distances. Venom was obtained from C. chiapanensis and C. salei by electrostimulation. The venom was separated by HPLC, visualized using SDS-PAGE, and quantified for use in toxicity bioassays in mice and insects. Results: Analysis of COI sequences from C. chiapanensis showed 94% identity with C. salei, while C. salei exhibited 94-97% identity with sequences from Central and South American conspecifics. The venom from C. chiapanensis exhibited toxic activity against crickets. Venoms from C. chiapanensis and C. salei caused death in Anastrepha obliqua flies. Analysis of venom fractions from C. salei and C. chiapanensis revealed molecular masses of a similar size as some previously reported toxins and neurotoxic components. We determined the amino acid sequences of ChiaTx1 and ChiaTx2, toxins that are reported here for the first time and which showed toxicity against mice and insects. Conclusion: Our work is the first to report COI-based DNA barcoding sequences from southern Mexican Cupiennius spiders. Compounds with toxic activity were identified in venom from both species.(AU)

Transcriptome analysis of the spider Phonotimpus pennimani reveals novel toxin transcripts.

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 have an important impact on the arthropod populations of its natural habitat. Methods: Specimens were collected in Southeastern Mexico (Chiapas) and identified taxonomically by morphological characteristics. A partial sequence from the mitochondrial gene coxI was amplified. Sequencing on the Illumina platform of a transcriptome library constructed from 12 adult specimens revealed 25 toxin or toxin-like genes. Transcripts were validated (RT-qPCR) by assessing the differential expression of the toxin-like PpenTox1 transcript and normalising with housekeeping genes. Results: Analysis of the coxI-gene revealed a similarity to other species of the family Phrurolithidae. Transcriptome analysis also revealed similarity with venom components of species from the families Ctenidae, Lycosidae, and Sicariidae. Expression of the toxin-like PpenTox1 gene was different for each developmental stage (juvenile or adult) and also for both sexes (female or male). Additionally, a partial sequence was obtained for the toxin-like PpenTox1 from DNA. Conclusion: Data from the amplification of the mitochondrial coxI gene confirmed that P. pennimani belongs to the family Phrurolithidae. New genes and transcripts coding for venom components were identified.

The guardstone spiders of the genus Phonotimpus Gertsch & Davis (Araneae: Phrurolithidae) from northeastern Mexico.

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. eutypus Gertsch & Davis, both previously known only from female specimens. Moreover, we describe 25 new species from Northeast Mexico (Nuevo León, Tamaulipas, and San Luis Potosí): P. ahuacatlan sp. nov., P. arcitos sp. nov., P. boneti sp. nov., P. calenturas sp. nov., P. chipinque sp. nov., P. cielo sp. nov., P. cima sp. nov., P. cuauhtemoc sp. nov., P. cumbres sp. nov., P. elviejo sp. nov., P. escondida sp. nov., P. farias sp. nov., P. frio sp. nov., P. gertschi sp. nov., P. llera sp. nov., P. perra sp. nov., P. pozas sp. nov., P. puente sp. nov., P. revilla sp. nov., P. sanpedro sp. nov., P. vacas sp. nov., P. valles sp. nov., P. taman sp. nov., P. tetrico sp. nov. and P. xilitla sp. nov. Furthermore, we propose five species groups that include almost all of the new species and all the species described to date.

A new species of the genus Phonotimpus Gertsch amp; Davis (Araneae: Phrurolithidae) from Mexico and the transfer of Gosiphrurus schulzefenai Chamberlin amp; Ivie to Phonotimpus.

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 the redescription of the female and first description of the male, with an update of the diagnosis of this species.

Four new species of the genus Novalena Chamberlin amp; Ivie, 1942 (Araneae: Agelenidae) from southeastern Mexican montane forests and first record of ocular anomaly in the genus.

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.

Diversity and seasonal variation of ground and understory spiders from a tropical mountain cloud forest.

We made intensive samplings to study the seasonal response of spiders across different forest strata (ground and understory) in a tropical mountain cloud forest from Mexico. We sampled spiders from ten plots in six sampling events during the dry and rainy season, to analyze their abundance, structure (distribution of abundance among species), diversity and the response of the five dominant species at each stratum. Results demonstrated that seasonal patterns of spider communities differed among strata, revealing a complex spatiotemporal dynamic. Abundance, structure, diversity of ground spiders, as well as the responses of four dominant species at this stratum, showed low seasonal variations. In contrast, a strong seasonal variation was observed for the understory assemblage, with lowest abundance and highest diversity in the rainy season, and different assemblage structures for each season. Seasonal patterns of each assemblage seem linked to the responses of their dominant species. We found high co-occurrence among most of the ground dominant species with similar habitat use and with multivoltine patterns, contrasting with low co-occurrence among most of the understory dominant species with similar habitat use and univoltine patterns. Our results showed that the spiders' assemblages of tropical mountain cloud forest (opposed to what is found in temperate and boreal forests) increase their species richness with the height, and that their responses to seasonal change differ between strata. Management programs of these habitats should consider the spatial and temporal variations found here, as a better understanding of their ecological dynamics is required to support their sustainable management.

A new species of Phonotimpus Gertsch Davis, 1940 (Araneae: Phrurolithidae) from Mexico.

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 the southernmost species in this genus (Chamé-Vázquez et al. 2018), and have restricted allopatric geographic distributions in Chiapas. This genus differs from other American phrurolithid genera by the following combination of characters: posterior eye row recurved, posterior median eyes closer to posterior lateral eyes than to each other, posterior median eyes smaller than posterior lateral eyes, females with dorsal scutum on the opisthosoma; palpi of males with retrolateral and dorsal tibial apophyses not joined at the base, and copulatory bulb with a conductor, embolus and embolar basal process (Gertsch Davis 1940; Penniman 1985; Chamé-Vázquez et al. 2018). In this paper, a new species of Phonotimpus is described and illustrated, based on specimens collected in soil of a pine-oak forest in the state of Mexico.

A new species of the spider genus Wirada (Araneae, Theridiidae) from Mexico, with taxonomic notes on the genus and a key to the species.

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, Levi (1967) described W. tijuca (male) from southeastern Brazil, and lately Lise et al. (2009) described W. sigillata Lise, Silva Bertocello, 2009 and W. araucaria Lise, Silva Bertocello, 2009 (males and females) from southern Brazil. Simon (1894) placed Wirada in its group Histogonieae, and stated it is close to Pholcommateae. Until now, none species of Wirada has been included in any phylogenetic study of Theridiidae, only Agnarsson (2004) when commented the Pholcommatinae said "Based on the synapomorphies of the group it is likely that ... Wirada belong to this subfamily." Recently, this genus was reported (as Wirada sp1) from two localities in Mexico (Ibarra et al. 2011; Álvarez-Padilla 2015; Rivera-Quiroz et al. 2016) and subsequent samplings on three other sites from Chiapas (Campuzano et al. 2016) exposed more specimens. After examining these specimens, we found they do not match any of the known species and therefore we propose a new species. We also include taxonomic and biological notes about the genus and a key to the species.

Redescription of Phonotimpus separatus Gertsch Davis, 1940 (Araneae: Phrurolithidae) and description of two new species of Phonotimpus from Mexico.

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 related taxa. The two new species are closely related; males and females of both species share several somatic and genitalic characters not found in P. separatus. The resemblance of both new species to P. separatus is discussed.

Natural Enemies of the Frankliniella Complex Species (Thysanoptera: Thripidae) in Ataulfo Mango Agroecosystems.

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: the orchard "Tres A" characterized by an intensive use of agrochemicals directed against thrips, and the orchard "La Escondida" that did not spray insecticides. During mango flowering, five inflorescences were randomly collected every 5 d in both orchards, for a total of 18 sampling dates. Results revealed the presence of 18 species of arthropods that were found predating on Frankliniella. There were 11 species in the families Aeolothripidae, Phlaeothripidae, Formicidae, Anthocoridae and Chrysopidae; and seven species of spiders in the families Araneidae, Tetragnathidae, and Uloboridae. Over 88% of predators were anthocorids, including, Paratriphleps sp. (Champion), Orius insidiosus (Say), Orius tristicolor (White), and O. perpunctatus (Reuter). The orchard that did not spray insecticides had a significantly higher number of predators suggesting a negative effect of the insecticides on the abundance of these organisms.

A new species of the spider genus Taczanowskia (Araneae, Araneidae) from Mexico.

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 of its opisthosoma. This species is included in an earlier determination key for all previously known Taczanowskia species.

Diversidad arbórea en cacaotales del Soconusco, Chiapas, México / The diversity in cacao plantations in the Soconusco Area, Chiapas, Mexico

Se estudiaron 80 parcelas productoras de cacao en cuatro áreas de la región del Soconusco, Chiapas, México, con el objetivo de conocer la diversidad arbórea. Se utilizaron los índices de diversidad de Shannon y de Simpson, y de similitud de Sørensen y de Morisita-Horn. Se establecieron 80 sitios de muestreo de 30×30m cada uno en donde se registró densidad, riqueza y diámetro a la altura del pecho. Se encontraron 47 especies agrupadas en 23 familias. Tapachula presentó diferencias significativas con los demás sitios al aplicar la prueba t de student a los valores del índice de Shannon entre pares de sitios; las otras tres áreas no mostraron diferencias estadísticas significativas y los índices de similitud mostraron diferencias entre pares de sitios. La composición florística en los cacaotales estudiados es similar entre los diferentes municipios, como lo muestran las reducidas diferencias entre los valores del índice de Sørensen. Las especies de sombra más frecuentemente encontradas fueron Mangifera indica y Pouteria sapota. Este estudio determina la existencia de solo un tipo de sistema agroforestal para los cacaotales del Soconusco.

Queen dimorphism and reproductive capacity in the ponerine ant, Ectatomma ruidum Roger.

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 thorax widths, and scutum and alitrunk lengths) was shown to be bimodal. Thorax width and head width were significantly isometric for both macro- and microgynes and thorax proportions did not change with the category of the queen. Microgynes appear as an isometric reduction of the normal queens. On average, macrogynes were found to be approximately 20% larger in size and twice as heavy as microgynes (and up to three times heavier in terms of dry weight). Their wing surface was 72% greater. There was no difference between the two morphs in terms of their capacity to be inseminated and all dealate females present in natural colonies could be considered as true potentially reproductive queens whatever the class to which they belonged. Ovary size, number of ovarioles per ovary, and number of mature oocytes produced were significantly higher for macrogynes than for microgynes, but small queens were able to function as active egg-layers. However, the number of egg-laying individuals was significantly lower for this form, although egg-laying activity appeared to be independent of queen weight. Despite its markedly reduced reproductive capacity compared to macrogynes, the distribution of the microgyne form of E. ruidum in both studied populations was very broad, reaching one-third of all alate and dealate females and extending to one-third of all colonies. In 72.2% of the colonies where alate and/or dealate microgynes were present, both forms co-occurred. Fat content analysis results supported the idea that semi-claustral independent colony founding, typical for this species, would essentially be achieved by macrogynes, while microgynes would be adopted by established colonies. We argue that queen dimorphism in E. ruidum could represent an attractive alternative dispersal strategy for female sexuals. The small females may constitute an important reserve of potential reproductives at a very low energetic cost to the colony, the production of a macrogyne being about 7.5 times more costly than a microgyne. The significantly greater `wing surface/body weight' ratio of microgynes also suggests their greater capacity for dispersion. The combination of such a capacity for microgynes, along with their ability to contribute in the production of both female morphs, including the reproductively efficient macrogynes, would contribute to insuring genetic reassortment at the population level and could explain, in part, the ecological success of E. ruidum in Neotropical zones.