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In myrmecophilous organisms, which live in symbiosis with ants, cuticular hydrocarbons (CHCs) play a pivotal role in interspecific communication and defense against chemical-oriented predators. Although these interactions form complex information webs, little is known about the influence of biotic environmental factors on the CHC profiles of myrmecophiles. Here, we analyzed the effect of different host plants and tending ants on the larval CHC profile of Synargis calyce (Lepidoptera: Riodinidae), a polyphagous species with facultative myrmecophily. Groups of caterpillars were fed individually with three host plant species (without tending ants), and with two tending ant species. Through gas chromatography analysis, we compared the cuticular profiles of treatments and found a high similarity between plants and caterpillars (65-82%), but a low similarity between caterpillars and their tending ants (30 - 25%). Cluster analysis showed that caterpillars, ants, and plants form distinct groups, indicating that S. calyce caterpillars have their own chemical profile. These results are similar to those observed for Lycaenidae caterpillars indicating that there is functional convergence in the chemical strategies used by myrmecophilous caterpillar species with similar ecology. Also, the results suggest that the cuticular compounds of S. calyce are primarily influenced by their host plants rather than their tending ants. Thus, we propose that these caterpillars present a trade-off between camouflage and directly informing their presence to ants, maintaining their unique chemical profile, though slightly affected by biotic environmental factors.

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Butterflies have a wide spectrum of colour vision, and changes in flower colour influence both the visiting and nectaring (the act of feeding on flower nectar) events of them. However, the spontaneous behavioural response of butterflies while foraging on real flowers is less characterised in wild conditions. Hence, this study intends to investigate flower colour affinity in wild butterflies in relation to nectaring frequency (NF) and nectaring duration (ND). Six distinct flower colours were used to study spontaneous nectaring behaviour in 20 species of subtropical butterflies. Both NF and ND greatly varied in the flower colours they offered. Yellow flowers were frequently imbibed by butterflies for longer durations, followed by orange, while red, pink, white and violet flowers were occasionally nectared in shorter bouts. Though butterflies have a general tendency to nectar on multiple flower colours, the Nymphalids were more biased towards nectaring on yellow flowers, but Papilionids preferred both yellow and orange, while the Pierids were likely to display an equal affinity for yellow, orange and violet flowers as their first order of preference. Even if the blooms are associated with higher nectar concentrations or a significant grade reward, the butterfly may prefer to visit different-coloured flowers instead. Flower colour choice appears to be a generalist phenomenon for butterflies, but their specialist visiting nature was also significant. Nymphalid representatives responded to a wider variety of floral colour affinities than Pierid and Papilionid species. The colour preference of butterflies aids in the identification of flowers during foraging and influences subsequent foraging decisions, which ultimately benefits pollination success. The current information will support the preservation and conservation of butterflies in their natural habitats.

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Background: Land use change is a key catalyst of global biodiversity loss and ecosystem degradation. Deforestation and conversion of natural habitats to agricultural or urban areas can profoundly disrupt plant-flower visitor interactions by altering their abundances and distribution. Yet, specific studies analyzing the effects of land use change on the structure of networks of the interactions between particular groups of flower visitors and their plants are still scarce. Here, we aimed to analyze how converting native habitats affects the species composition of butterfly communities and their plants, and whether this, in turn, leads to changes in the structure of interaction networks in the modified habitats. Methods: We performed bi-monthly censuses for a year to record plant-butterfly interactions and assess species diversity across three habitat types, reflecting a land-use change gradient. From original native juniper forest to urban and agricultural zones in central Mexico, one site per land use type was surveyed. Interactions were summarized in matrices on which we calculated network descriptors: connectance, nestedness and modularity. Results: We found highest butterfly diversity in native forest, with the most unique species (i.e., species not shared with the other two sites). Agricultural and urban sites had similar diversity, yet the urban site featured more unique species. The plant species richness was highest in the urban site, and the native forest site had the lowest plant species richness, with most of the plants being unique to this site. Butterfly and plant compositions contrasted most between native forest and modified sites. Network analysis showed differences between sites in the mean number of links and interactions. The urban network surpassed agriculture and native forest networks in links, while the native forest network had more interactions than the agriculture and urban networks. Native plants had more interactions than alien species. All networks exhibited low connectance and significant nestedness and modularity, with the urban network featuring the most modules (i.e., 10 modules). Conclusions: Converting native habitats to urban or agricultural areas reshapes species composition, diversity and interaction network structure for butterfly communities and plants. The urban network showed more links and modules, suggesting intricate urban ecosystems due to diverse species, enhanced resources, and ecological niches encouraging interactions and coexistence. These findings emphasize the impacts of land use change on plant-butterfly interactions and the structure of their interaction networks.

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Habitat fragmentation and ecosystem changes have the potential to affect animal populations in different ways. To effectively monitor these changes, biomonitoring tools have been developed and applied to detect changes in population structure and/or individual traits that reflect such changes. Fluctuating asymmetry (FA) represents random deviations from perfect symmetry in bilateral traits from perfect symmetry in response to genetic and/or environmental stresses. In this study, we evaluated the use of FA as a tool to monitor stress caused by forest fragmentation and edge formation, using the tropical butterfly M. helenor (Nymphalidae) as a model species. We collected adult butterflies from three fragments of Atlantic Forest in Brazil encompassing both edge and interior habitats. Four wing traits (wing length, wing width, ocelli area, and ocelli diameter) were evaluated. Butterflies captured at edge sites exhibited higher FA values for wing length and wing width compared to those captured at interior sites, whereas traits related to ocelli did not show differences between the two habitat types. Our results suggest that the differences in abiotic and biotic conditions between forest interior and edges can act as a source of stress, impacting the symmetry of flight-related traits. On the other hand, as ocelli are crucial for butterfly camouflage and counter-predator strategies, our results indicate that this trait may be more conserved. By employing FA, we identified trait-specific responses to habitat fragmentation, thus suggesting its potential as a biomarker for environmental stress that can be used in butterflies to monitor habitat quality and change.

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Abstract Introduction: The effects of habitat transformation have been widely studied and the effects are well-known at different levels of biological organization. However, few studies have focused on responses to this process at the level of multiple taxa in diverse taxonomic and functional groups. Objective: Determine the variations in taxonomic and functional diversity of ants, butterflies, and dung beetles, at a spatial and temporal level in a landscape mosaic of the ecoregion of the Colombian foothills. Methods: We assessed amount of natural habitat and landscape composition in four types of vegetation, during the highest and lowest rain periods. We collected butterflies with hand nets and used baited pitfall traps for dung beetles and ants. Results: Habitat loss positively affected ant and butterfly species richness, and negatively affected dung beetles. The abundance of ants and butterflies had a positive effect on the dominance of species in the transformed vegetation, for dung beetles the abundance was negatively affected by the absence of canopy cover. Habitat loss had no negative effect on functional diversity as there is no difference between natural and transformed vegetation. Conclusions: The amount of habitat, habitat connectivity and different types of vegetation cover were important factors in the maintenance of insect diversity in the modified ecosystems of foothills of the Colombian Orinoquia. The lack of a common spatial and temporal pattern shows that studies of multiple insect taxa should be carried out for biodiversity monitoring and conservation processes.

Resumen Introducción: Los efectos de la transformación del hábitat han sido ampliamente estudiados y son bien conocidos los efectos a diferentes niveles de organización biológica. Sin embargo, pocos estudios se han centrado en las respuestas a este proceso a nivel de múltiples taxones en diversos grupos taxonómicos y funcionales. Objetivo: Determinar las variaciones en la diversidad taxonómica y funcional de hormigas, mariposas y escarabajos coprófagos, a nivel espacial y temporal en un mosaico paisajístico de la ecorregión del piedemonte colombiano. Métodos: Evaluamos la cantidad de hábitat natural y la composición del paisaje en cuatro tipos de vegetación, durante los períodos de mayor y menor lluvia. Recolectamos mariposas con redes de mano y usamos trampas de caída con cebo para escarabajos coprófagos y hormigas. Resultados: La pérdida de hábitat afectó positivamente la riqueza de especies de hormigas y mariposas y afectó negativamente a los escarabajos peloteros. La abundancia de hormigas y mariposas tuvo un efecto positivo sobre la dominancia de especies en la vegetación transformada, para los escarabajos coprófagos la abundancia se vio afectada negativamente por la ausencia de cobertura de dosel. La pérdida de hábitat no tuvo un efecto negativo sobre la diversidad funcional ya que no hay diferencia entre la vegetación natural y la transformada. Conclusiones: La cantidad de hábitat, la conectividad del hábitat y los diferentes tipos de cobertura vegetal fueron factores importantes en el mantenimiento de la diversidad de insectos en los ecosistemas modificados del piedemonte de la Orinoquia colombiana. La falta de un patrón espacial y temporal común muestra que se deben realizar estudios de múltiples taxones de insectos para los procesos de monitoreo y conservación de la biodiversidad.

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Abstract Introduction: The Loxicha Region of Oaxaca, Mexico, has been historically important for the study of Nymphalidae, second in the Papilionoidea for species richness. Describing the diversity patterns of this butterfly clade in Loxicha can improve our understanding of the evolutionary history of the Sierra Madre del Sur, the Mexican Pacific slope, and Mexico in general. Objective: To describe the temporal and spatial patterns of Nymphalidae diversity along an elevational gradient (80-2 600 m), and to compare Loxicha's fauna with other regions in Mexico. Methods: We obtained 28 756 records from 21 sites in the Loxicha Region, representing seven years of sampling. We estimate and analyze the diversity, endemism, and distributional patterns for three elevational levels and five vegetation types. We estimated species composition and similarity with other regions of the Pacific and Atlantic slopes. Results: We identified 189 taxa, including species and subspecies, from 85 genera and ten subfamilies of Nymphalidae. Loxicha contains 46 % of the species in the family recognized for Mexico, including ten endemic species and 56 endemic subspecies. Cloud forest and low elevations were the most diverse habitats for this family. There is a clear divergence between the Atlantic and Pacific faunas, and the Sierra Madre del Sur has two faunal components. High-elevation sites in Oaxaca, and in the neighboring state of Guerrero, have a distinctive fauna, apparently isolated from low-elevation sites, revealing an archipelagic distribution for cloud forest Nymphalidae. Conclusions: The Loxicha Region is one of the richest areas for Nymphalidae in Mexico. Distribution on the Pacific slope is determined by geographical history and ecological conditions, including elevation. Nymphalidae can be used to test hypotheses of biogeographic regionalization in Mexico.

Resumen Introducción: La Región Loxicha de Oaxaca, México, ha sido históricamente importante para el estudio de Nymphalidae, segunda en riqueza de especies en Papilionoidea. Describir los patrones de diversidad de este taxón de mariposas en Loxicha puede mejorar nuestra comprensión de la historia evolutiva de la Sierra Madre del Sur, la vertiente del Pacífico mexicano y México en general. Objetivo: Describir los patrones temporales y espaciales de la diversidad de Nymphalidae a lo largo de un gradiente altitudinal (80-2 600 m), y comparar la fauna de Loxicha con otras regiones de México. Métodos: Obtuvimos 28 756 registros de 21 sitios de la Región Loxicha, que representan siete años de muestreo. Estimamos y analizamos la diversidad, el endemismo y los patrones de distribución para tres niveles altitudinales y cinco tipos de vegetación. Estimamos la composición de especies y la similitud con otras regiones de las vertientes del Pacífico y Atlántico de México. Resultados: Identificamos 189 taxones, incluyendo especies y subespecies, de 85 géneros y diez subfamilias de Nymphalidae. Loxicha contiene 46 % de las especies de la familia reconocidas para México, incluidas diez especies endémicas y 56 subespecies endémicas. El bosque mesófilo y las elevaciones bajas fueron los hábitats más diversos para esta familia. Existe una clara divergencia entre las faunas del Atlántico y del Pacífico, y la Sierra Madre del Sur tiene dos componentes faunísticos. Los sitios de elevaciones altas en Oaxaca, y en el estado vecino de Guerrero, tienen una fauna distintiva, aparentemente aislada de los sitios de elevaciones bajas, lo que revela una distribución archipelágica para los Nymphalidae del bosque mesófilo. Conclusiones: La Región Loxicha es una de las zonas más diversas para Nymphalidae en México. La distribución en la vertiente del Pacífico está determinada por la historia geográfica y las condiciones ecológicas, incluida la elevación. Nymphalidae puede usarse para probar hipótesis de regionalización biogeográfica en México.

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Recent reviews of data on worldwide insect decline include almost no information on Brazil. We gathered evidence from literature searches and a survey sent to researchers, to which 96 replied and 56 provided information and publications. We present 75 instances of trends recorded over an average span of 11 years for aquatic and 22 years for terrestrial insects. These include time-replicated samples and expert opinion based on long-term local collections. Most terrestrial data are for butterflies, bees and scarab beetles. Aquatic studies include several insect orders, usually sorted to genus or family. Terrestrial insects showed significantly more cases of declines than increases, both in abundance (17 : 3) and in diversity (11 : 1). In aquatic cases, no tendency was detected in abundance (2 : 2) or diversity (3 : 4), not counting cases with no trend. Differences in these results among habitats may be due to the shorter span and less change in environmental conditions in the aquatic surveys, which included sites already degraded before sampling. We offer guidelines for future long-term assessments, including resampling of legacy collection sites.

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RESUMEN La estructura genética de poblaciones de mariposas con distribución en islas y sus pares continentales ha sido poco documentada para el neotrópico. Este estudio presenta la caracterización de una población de Heliconius sara con distribución en la Isla Gorgona, ubicada en la región del Pacífico Oriental Colombiano. Para esto se examinaron secuencias parciales de un marcador mitocondrial incluyendo información obtenida del GenBank. Se comparó la diversidad y estructura genética con sus conespecíficos continentales y también con congéneres, con los que comparte un ancestro común cercano en el clado Sapho-Sara. Para el análisis de diversidad y estructura genética se realizó un análisis de varianza molecular. Este análisis muestra que la distancia entre la población de la isla y sus pares en el continente es consistente con la variación intraespecífica observada en otras especies del género Heliconius. Para la reconstrucción de la genealogía y datación reciente en el Pleistoceno superior del grupo monofilético de secuencias de H. sara, se realizó un análisis de inferencia bayesiana, así como una de máxima verosimilitud. Del análisis demográfico se seleccionó un modelo histórico de flujo asimétrico desde la isla hacia el continente que sugiere baja resistencia de la discontinuidad geográfica a la dispersión de esta mariposa diurna desde la isla. Este es el primer estudio en examinar un posible evento de aislamiento de una población insular de mariposas en Colombia.

ABSTRACT The genetic structure of butterfly populations among islands and mainland has been poorly documented for the neotropics. This study shows a characterization of the Heliconius sara population with distribution on Gorgona Island in the Colombian Eastern Tropical Pacific region. We obtained partial sequences of a mitochondrial DNA, including information obtained from GenBank. The genetic diversity and structure were compared among the island population and their mainland conspecific, but also with congenerics, with those shared by a recent common ancestor within the Sapho/Sara clade. For the analysis of diversity and genetic structure, an analysis of molecular variance was performed. This analysis shows that the genetic distance between the island's population and that of the mainland is consistent with the intraspecific variation observed in other species of the Heliconious genus. For the reconstruction of the genealogy and the recent dating calibration in the upper Pleistocene of the monophyletic group of H. sara, a Bayesian inference was carried out as well as one of maximum likelihood. From the demographic analysis, an asymmetric gene flow model from the island to the mainland was selected. This model suggests low historical resistance of the geographic discontinuity to dispersal of this small and diurnal butterfly from the island. This is the first study to examine a possible event of local isolation of an island population of a butterfly in Colombia.

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Jonaspyge elizabethae n. sp. is described from southwestern Honduras. It is similar to the other two Jonaspyge O. Mielke, 2002 species in having metallic dark-blue wings with purple sheen, crenulate hindwing outer margin, and black body with orange palpi and an orange abdomen tip. It is diagnosed by bright-orange (instead of white) fringes and dark (instead of orange) cheeks. Genomic sequence analysis of Jonaspyge reveals that it is a close relative of Jonaspyge jonas (C. Felder & R. Felder, 1859) and Jonaspyge tzotzili (H. Freeman, 1969), differing from them by 5.3% in the COI DNA barcode. This new, third species of Jonaspyge is the most divergent member of the genus.

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Emesis eleanorae Gallardo & Grishin n. sp. is described from western Honduras. It differs from other species of Emesis Fabricius, 1807 in having a row of prominent iron-gray crescent-shaped postdiscal spots on both wings above, outlined by paler areas basad and mirrored as merlot-colored spots below, with the largest by the forewing costa, and in its females being bright golden-orange in color. Genomic sequence analysis of Emesis reveals that the new species belongs to the subgenus Aphacitis Hübner, [1819] and is sister to the clade containing Emesis diogenia Prittwitz, 1865 and Emesis heteroclita Stichel, 1929, and the clade of these three species is sister to Emesis vulpina Godman & Salvin, 1886.

Emesis eleanorae Gallardo & Grishin n. sp. se describe desde el Occidente de Honduras. Se diferencia de otras especies de Emesis Fabricius, 1807 por tener una fila de prominentes puntos postdiscales en forma de media luna, color gris-hierro en la parte de arriba de ambas alas, delineadas por áreas más pálidas y reflejadas debajo como manchas de color merlot, las cuales son más grandes en la costa delantera, y en las hembras son de color dorado-anaranjado brillante. El análisis de la secuencia genómica de Emesis revela que la nueva especie pertenece al subgénero Aphacitis Hübner, [1819] y es pariente del clado de Emesis diogenia Prittwitz, 1865 y Emesis heteroclita Stichel, 1929, y el clado de estas tres especies son parientes de Emesis vulpina Godman y Salvin, 1886.

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The first phylogenetic hypotheses for the high Andean satyrine butterfly genus Altopedaliodes is proposed based on sequence data from mitochondrial (COI and COII) and nuclear (EF-1α) genes. Four species previously included in the genus were found not to be closely related to the clade containing the type species for Altopedaliodes, and these species are therefore removed and placed in the appropriate genus: Pedaliodes cocytia (C. Felder and R. Felder, 1867) n. comb., Pedaliodes nebris Thieme 1905rev. comb., Neopedaliodes tamaensis (Pyrcz and Viloria 2007) n. comb., and Altopedaliodes similis Henao, Páez and Rodríguez-M., 2017; the last name is here synonymized with Pedaliodes nebris (Thieme 1905) n. syn. A taxonomic revision of the twelve species in Altopedaliodes as newly circumscribed is presented and all the currently recognized taxa are revised. We describe two new species, A. llanganati Padrón, Pyrcz and Willmott n. sp. (Ecuador, Napo) and A. pilimbala Pyrcz and Boyer n. sp. (Colombia, Cauca), and three new subspecies, A. reissi papallacta Padrón, Pyrcz and Willmott n. ssp. (Ecuador, Napo), A. reissi dominica Pyrcz and Padrón n. ssp. (Colombia, Valle del Cauca) and A. halli cagnoni Boyer, Pyrcz and Padrón n. ssp. (Ecuador, Morona-Santiago). A new status is proposed for A. nucea Pyrcz and Viloria 1999, n. stat., we combine Altopedaliodes scydmaena (Hayward, 1968) n. comb. and Altopedaliodes belmira (Pyrcz and Rodríguez, 2004), n. comb., n. stat. into the genus and treat the latter taxon as a species, and we newly treat Altopedaliodes scydmaena kruegeri Pyrcz 1999n. stat. as a subspecies.

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BACKGROUND: With about 1,000 species in the Neotropics, the Eumaeini (Theclinae) are one of the most diverse butterfly tribes. Correct morphology-based identifications are challenging in many genera due to relatively little interspecific differences in wing patterns. Geographic infraspecific variation is sometimes more substantial than variation between species. In this paper we present a large DNA barcode dataset of South American Lycaenidae. We analyze how well DNA barcode BINs match morphologically delimited species. METHODS: We compare morphology-based species identifications with the clustering of molecular operational taxonomic units (MOTUs) delimitated by the RESL algorithm in BOLD, which assigns Barcode Index Numbers (BINs). We examine intra- and interspecific divergences for genera represented by at least four morphospecies. We discuss the existence of local barcode gaps in a genus by genus analysis. We also note differences in the percentage of species with barcode gaps in groups of lowland and high mountain genera. RESULTS: We identified 2,213 specimens and obtained 1,839 sequences of 512 species in 90 genera. Overall, the mean intraspecific divergence value of CO1 sequences was 1.20%, while the mean interspecific divergence between nearest congeneric neighbors was 4.89%, demonstrating the presence of a barcode gap. However, the gap seemed to disappear from the entire set when comparing the maximum intraspecific distance (8.40%) with the minimum interspecific distance (0.40%). Clear barcode gaps are present in many genera but absent in others. From the set of specimens that yielded COI fragment lengths of at least 650 bp, 75% of the a priori morphology-based identifications were unambiguously assigned to a single Barcode Index Number (BIN). However, after a taxonomic a posteriori review, the percentage of matched identifications rose to 85%. BIN splitting was observed for 17% of the species and BIN sharing for 9%. We found that genera that contain primarily lowland species show higher percentages of local barcode gaps and congruence between BINs and morphology than genera that contain exclusively high montane species. The divergence values to the nearest neighbors were significantly lower in high Andean species while the intra-specific divergence values were significantly lower in the lowland species. These results raise questions regarding the causes of observed low inter and high intraspecific genetic variation. We discuss incomplete lineage sorting and hybridization as most likely causes of this phenomenon, as the montane species concerned are relatively young and hybridization is probable. The release of our data set represents an essential baseline for a reference library for biological assessment studies of butterflies in mega diverse countries using modern high-throughput technologies an highlights the necessity of taxonomic revisions for various genera combining both molecular and morphological data.

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BACKGROUND: A key challenge for conservation biology in the Neotropics is to understand how deforestation affects biodiversity at various levels of landscape fragmentation. Addressing this challenge requires expanding the coverage of known biodiversity data, which remain to date restricted to a few well-surveyed regions. Here, we assess the sampling coverage and biases in biodiversity data on fruit-feeding butterflies at the Brazilian Atlantic Forest, discussing their effect on our understanding of the relationship between forest fragmentation and biodiversity at a large-scale. We hypothesize that sampling effort is biased towards large and connected fragments, which occur jointly in space at the Atlantic forest. METHODS: We used a comprehensive dataset of Atlantic Forest fruit-feeding butterfly communities to test for sampling biases towards specific geographical areas, climate conditions and landscape configurations. RESULTS: We found a pattern of geographical aggregation of sampling sites, independently of scale, and a strong sampling bias towards large and connected forest fragments, located near cities and roads. Sampling gaps are particularly acute in small and disconnected forest fragments and rare climate conditions. In contrast, currently available data can provide a fair picture of fruit-feeding butterfly communities in large and connected Atlantic Forest remnants. DISCUSSION: Biased data hamper the inference of the functional relationship between deforestation and biodiversity at a large-scale, since they are geographically clustered and have sampling gaps in small and disconnected fragments. These data are useful to inform decision-makers regarding conservation efforts to curb biodiversity loss in the Atlantic Forest. Thus, we suggest to expand sampling effort to small and disconnected forest fragments, which would allow more accurate evaluations of the effects of landscape modification.

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Previous studies of butterfly diversification in the Neotropics have focused on Amazonia and the tropical Andes, while southern regions of the continent have received little attention. To address the gap in knowledge about the Lepidoptera of temperate South America, we analysed over 3000 specimens representing nearly 500 species from Argentina for a segment of the mitochondrial cytochrome c oxidase subunit I (COI) gene. Representing 42% of the country's butterfly fauna, collections targeted species from the Atlantic and Andean forests, and biodiversity hotspots that were previously connected but are now isolated. We assessed COI effectiveness for species discrimination and identification and how its performance was affected by geographic distances and taxon coverage. COI data also allowed to study patterns of genetic variation across Argentina, particularly between populations in the Atlantic and Andean forests. Our results show that COI discriminates species well, but that identification success is reduced on average by ~20% as spatial and taxonomic coverage rises. We also found that levels of genetic variation are associated with species' spatial distribution type, a pattern which might reflect differences in their dispersal and colonization abilities. In particular, intraspecific distance between populations in the Atlantic and Andean forests was significantly higher in species with disjunct distributions than in those with a continuous range. All splits between lineages in these forests dated to the Pleistocene, but divergence dates varied considerably, suggesting that historical connections between the Atlantic and Andean forests have differentially affected their shared butterfly fauna. Our study supports the fact that large-scale assessments of mitochondrial DNA variation are a powerful tool for evolutionary studies.

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Aerodynamic efficiency behind the annual migration of monarch butterflies, the longest among insects, is an unsolved mystery. Monarchs migrate 4000 km at high-altitudes to their overwintering mountains in Central Mexico. The air is thinner at higher altitudes, yielding reduced aerodynamic drag and enhanced range. However, the lift is also expected to reduce in lower density conditions. To investigate the ability of monarchs to produce sufficient lift to fly in thinner air, we measured the climbing motion of freely flying monarchs in high-altitude conditions. An optical method was used to track the flapping wing and body motions inside a large pressure chamber. The air density inside the chamber was reduced to recreate the higher altitude densities. The lift coefficient generated by monarchs increased from 1.7 at the sea-level to 9.4 at 3000 m. The correlation between this increase and the flapping amplitude and frequency was insignificant. However, it strongly correlated to the effective angle of attack, which measures the wing to body velocity ratio. These results support the hypothesis that monarchs produce sufficiently high lift coefficients at high altitudes despite a lower dynamic pressure.

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Müllerian mimicry strongly exemplifies the power of natural selection. However, the exact measure of such adaptive phenotypic convergence and the possible causes of its imperfection often remain unidentified. Here, we first quantify wing colour pattern differences in the forewing region of 14 co-mimetic colour pattern morphs of the butterfly species Heliconius erato and Heliconius melpomene and measure the extent to which mimicking colour pattern morphs are not perfectly identical. Next, using gene-editing CRISPR/Cas9 KO experiments of the gene WntA, which has been mapped to colour pattern diversity in these butterflies, we explore the exact areas of the wings in which WntA affects colour pattern formation differently in H. erato and H. melpomene. We find that, while the relative size of the forewing pattern is generally nearly identical between co-mimics, the CRISPR/Cas9 KO results highlight divergent boundaries in the wing that prevent the co-mimics from achieving perfect mimicry. We suggest that this mismatch may be explained by divergence in the gene regulatory network that defines wing colour patterning in both species, thus constraining morphological evolution even between closely related species.

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Flower cues serve as information that improves foraging by flower visitors. These cues may act in a synergic, redundant or complementary way. We examined how the integration of visual cues affects foraging in the southern monarch butterfly, and whether these combined cues can be learned. Artificial flowers having two flower cues, colouration pattern (uniform or radial) and dimension (2D or 3D), were employed in laboratory experiments. We assumed that uniform flowers are less informative than radial ones, and that bi-dimensionality is less informative than tri-dimensionality. These cues resulted in four floral types (uniform 2D, radial 2D, uniform 3D and radial 3D). Two- and multiple choice tests were run to investigate whether butterflies show more attraction to more informative flowers than less informative ones. Flower cues acted in a complementary way, as more informative flowers were preferred by southern monarchs than less informative ones. In a multiple-choice scenario, uniform 2D flowers received less visits than radial flowers of both dimensions. In a second experiment, butterflies were conditioned to the four flower types. No conditioning occurred, as radial flowers were visited consistently more than uniform flowers. Our results show that southern monarchs take integrated flower information into account for foraging decisions, and that learning does not occur when highly informative flowers are present.

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Telemiades Hübner, [1819] is currently comprised of 22 species and 14 subspecies distributed exclusively in the neotropics. The genus is defined by the morphological pattern of the uncus, apiculus, labial palpi and venation. However, some species have a uniform pattern of coloration making it difficult to establish their correct identity in some cases. The aims of the present study were to present a taxonomic revision of Telemiades Hübner, [1819] in order to provide a stable taxonomic hypothesis for the group, to describe the new species and to present diagnoses to help in species identification. According to the present study, Telemiades is now composed of 41 species. Fourteen new species are recognized and described. Three subspecies are here treated as valid species: T. marpesus (Hewitson, 1876) stat. rest., T. misitheus Mabille, 1888 stat. rest. and T. pekahia (Hewitson, 1868) stat. rest. Two synonyms are treated as valid species: T. insulsus (Draudt, 1922), stat. rev. and T. xantho Hayward, 1939 stat. rev. Five new synonyms are proposed: Plesioneura lamus Mabille, 1888 syn. nov. and Telemiades antiope tosca Evans, 1953 syn. nov. of T. antiope (Plötz, 1882), Echelatus punctatus Mabille Boullet, 1917 syn. nov. of T. epicalus Hübner, [1819], Proteides nicola Plötz, 1882 syn. nov. of T. laogonus (Hewitson, 1876) and Eudamus phlius Plötz, 1881 syn. nov. of T. nicomedes (Möschler, 1879). To provide stability for existing names, six neotypes were designated for: Proteides amphion Geyer, 1832, Plesioneura compressa Möschler, 1877, Papilio avitus Stoll, 1781, Telegonus mygdon Möschler, 1877, Proteides aesopus Plötz, 1882 and Papilio corbulo Stoll, 1781; and 19 lectotypes for: Aethilla buffumi Weeks, 1906, Eudamus marpesus Hewitson, 1876, Telemiades misitheus Mabille, 1888, Pterygospidea pekahia Hewitson, 1868, Telemiades lurideolus Mabille, 1877, Eudamus laogonus Hewitson, 1876, Eudamus penidas Hewitson, 1867, Telemiades ceramina Herrich-Schäffer, 1869, Telemiades megalloides Schaus, 1902, Pythonides hoyti Weeks, 1906, Eudamus praestes Hewitson, 1876, Telemiades epicalus Hübner, [1819], Eudamus phasias Hewitson, 1867, Telemiades arcturus Herrich-Schäffer, 1869, Echelatus punctatus Mabille Boullet, 1917, Eudamus centrites Hewitson, 1870, Telegonus gallius Mabille, 1888, Telegonus nicomedes Möschler, 1879, and Arteurotia meris Plötz, 1886.

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Introduction: A reliable list of species and the analysis of diversity patterns of hyperdiverse taxa, like butterflies, are fundamental for monitoring and managing biological resources. Oaxaca is one of the most diverse states in Mexico for many groups including Lepidoptera and most of its diversity is unknown. Objective: To estimate and describe the species richness and diversity of Papilionidae and Pieridae along an altitudinal gradient and five vegetation types in the Loxicha Region, Oaxaca, Sierra Madre del Sur. Methods: Sampling effort comprised 222 collecting days during a period of seven years. We estimated the alpha diversity for 17 sites within an elevational gradient from 80 to 2 850 m, with five vegetation types: tropical deciduous forest (TDF), tropical sub-deciduous forest (TSDF), cloud forest (low and middle levels) (CF), oak-pine and cloud forest (high level) (OPCF) and oak-pine forest (OPF). Results: We obtained a list of 69 species (27 Papilionidae and 42 Pieridae), of 34 genera and five subfamilies, from literature records and fieldwork. These species are 60 % of the Pieridae and 48 % of the Papilionidae recorded for the state. The Loxicha Region has 36 % of the Pieridae and 30 % of the Papilionidae of Mexico. Both families present different species richness patterns by vegetation type. Papilionidae is richer in the TDF with 23 estimated species and most of the species of this family (84 %) occur below 500 m. Meanwhile, species richness of Pieridae has non-significant differences among vegetations types, except for OPF which has fewer species than the other types. The elevational gradient was divided into three levels (0-750, 750-1 800, 1 800-2 850 m) showing a reduction of species richness and diversity for both families at higher altitudes. Conclusions: Papilionidae species are more restricted to a vegetation type or elevational level than Pieridae species. Likely reasons are higher vagility (including migrations) and wider ecological tolerance of most Pieridae.

Introducción: Una lista de especies confiable y el análisis de los patrones de diversidad de taxones hiperdiversos, como las mariposas, son fundamentales para el monitoreo y manejo de recursos biológicos. Oaxaca es uno de los estados más diversos de México y mucha de su diversidad aun es desconocida. Objetivo: Estimar y describir la riqueza de especies y diversidad de Papilionidae y Pieridae en un gradiente altitudinal y cinco tipos de vegetación presentes en la Región Loxicha, Oaxaca, en la Sierra Madre del Sur. Métodos: El esfuerzo de muestreo comprendió 222 días a lo largo de siete años. Se estima la diversidad alfa para 17 sitios dentro de un gradiente altitudinal de 880 a 2 850 m con cinco tipos de vegetación: bosque tropical caducifolio, bosque tropical subcaducifolio, bosque mesófilo (nivel bajo y medio), bosque de pino-encino con bosque mesófilo (nivel alto) y bosque de pino-encino. Resultados: Se obtuvo una lista de 69 especies (27 Papilionidae y 42 Pieridae), de 34 géneros y cinco subfamilias, a partir de los registros en la literatura y el trabajo de campo. Estas especies representan el 60 % de los Pieridae y el 48 % de los Papilionidae registrados para el estado. A nivel nacional, la región Loxicha tiene el 36 % de las Pieridae y el 30 % de las Papilionidae del país. Las familias presentan patrones diferentes de riqueza de especies por tipo de vegetación. Papilionidae es más rica en el bosque tropical caducifolio con 23 especies estimadas y la mayoría de las especies de esta familia (84 %) están por debajo de los 500 m Mientras que la riqueza de especies de Pieridae no presenta diferencias significativas entre los tipos de vegetación, excepto por el bosque de pino-encino que tiene menos especies que los demás tipos. El gradiente altitudinal se dividió en tres pisos (0-750, 750-1 800, 1 800-2 850 m) con una reducción de la riqueza de especies y diversidad de ambas familias en altitudes mayores. Conclusiones: Las especies de Papilionidae están más restringidas a un tipo de vegetación o piso altitudinal que las especies de Pieridae. Probablemente por la gran vagilidad, valencia ecológica más amplia y capacidad de migraciones altitudinales de la mayoría de las Pieridae.

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Rainfall is one of the most influential factors driving insect seasonality in the Amazon region. However, few studies have analyzed the temporal dynamics of fruit-feeding butterflies in the Brazilian Amazon, specially in its eastern portion. Here, we evaluated the diversity patterns and temporal distribution of fruit-feeding butterflies in a remnant of eastern Amazon forest in the Baixada Maranhense, northeastern Brazil. Specifically, we tested whether fruit-feeding butterflies are temporally structured and whether rainfall influences species richness and abundance. Butterflies were collected with baited traps in both the rainy and dry seasons for two consecutive years. In total, we captured 493 butterflies belonging to 28 species, 15 genera and eight tribes. Three species comprised about half of the overall abundance, and Satyrinae was the most representative subfamily. The fruit-feeding butterfly assemblage showed a strong temporal structure during the second year of sampling, but not during the first year. Species composition and richness did not differ between rainy and dry seasons, and neither abundance nor richness was influenced by rainfall. Our results indicate that seasonality is not a strong environmental filter in this region, and that other biotic and abiotic factors are probably driving the community structure. The predominance of palms in the Baixada Maranhense, which are used as host plants by larvae of several lepidopteran species (specially satyrines) and are available year-round, might have contributed to the observed patterns of temporal diversity. (AU)

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