Obligatory ant-plant symbioses often appear to be single evolutionary shifts within particular ant lineages; however, convergence can be revealed once natural history observations are complemented with molecular phylogenetics. Here, we describe a remarkable example of convergent evolution in an ant-plant symbiotic system. Exclusively arboreal, Myrmelachista species can be generalized opportunists nesting in several plant species or obligately symbiotic, live-stem nesters of a narrow set of plant species. Instances of specialization within Myrmelachista are known from northern South America and throughout Middle America. In Middle America, a diverse radiation of specialists occupies understory treelets of lowland rainforests. The morphological and behavioural uniformity of specialists suggests that they form a monophyletic assemblage, diversifying after a single origin of specialization. Using ultraconserved element phylogenomics and ancestral state reconstructions, we show that shifts from opportunistic to obligately symbiotic evolved independently in South and Middle America. Furthermore, our analyses support a remarkable case of convergence within the Middle American radiation, with two independently evolved specialist clades, arising nearly simultaneously from putative opportunistic ancestors during the late Pliocene. This repeated evolution of a complex phenotype suggests similar mechanisms behind trait shifts from opportunists to specialists, generating further questions about the selective forces driving specialization.

Artifacts produced by postmortem animal scavenging are commonly encountered at autopsy. Knowledge of the pattern of artifacts produced by postmortem animal scavenging is essential for the correct interpretation of the autopsy finding. In household deaths, such artifacts are usually caused by domestic animals and by small insects such as flies, ants, beetles, etc. Ants are one of the early scavengers which feed on the dead bodies. The artifacts produced by the postmortem ant activity are usually superficial and non-bleeding type. Rarely, in the congested body regions and areas of marked hypostasis, postmortem bleeding artifacts due to ant bites are possible. In the reported case of hanging, such postmortem bleeding artifacts were present over both the legs, predominantly over the left leg. Typical ant bite lesions in the form of superficial excoriations were also present over the peri-ligature area, over and around both nipples and over the lower part of the abdomen. Morphologically, postmortem bleeding artifacts produced by ant bites exhibit four patterns: droplet pattern, stripe pattern, pool pattern, and mixed pattern. In this case, a mixed pattern (droplet pattern and stripe pattern) of postmortem bleeding artifacts was observed. The presence of postmortem bleeding artifacts over the lower limbs was attributed to the pooling of the blood due to suspension of the body, followed by passive escape of blood due to ant bites. The possibility of such artifacts produced by ant bites should be considered when the origin of the lesion is unclear.

The selection of explanatory variables is important in modeling prediction of changes in species distribution in response to climate change. In this study, we evaluated the importance of variable selection in species distribution models. We compared two different types of models for predicting the distribution of ant species: temperature-only and both temperature and precipitation. Ants were collected at 343 forest sites across South Korea from 2006 through 2009. We used a generalized additive model (GAM) to predict the future distribution of 16 species that showed significant responses to changes in climatic factors (temperature and/or precipitation). Four types of GAMs were constructed: temperature, temperature with interaction of precipitation, temperature and precipitation without interaction, and temperature and precipitation with interaction. Most species displayed similar results between the temperatureonly and the temperature and precipitation models. The results for predicted changes in species richness were different from the temperature-only model. This indicates higher uncertainty in the prediction of species richness, which is obtained by combining the prediction results of distribution change for each species, than in the prediction of distribution change. The turnover rate of the ant assemblages was predicted to increase with decreases in temperature and increases in elevation, which was consistent with other studies. Finally, our results showed that the prediction of the distribution or diversity of organisms responding to climate change is uncertain because of the high variability of the model outputs induced by the variables used in the models.

A growing body of literature recognizes that pairwise species interactions are not necessarily an appropriate metaphorical molecule of community ecology. Two examples are intransitive competition and nonlinear higher-order effects. While these two processes have been discussed extensively, the explicit analysis of how the two of them behave when simultaneously part of the same dynamic system has not yet been explored theoretically. A concrete situation exists on coffee farms in Puerto Rico in which three ant species form an intransitive competitive triplet, and that triplet is strongly influenced, nonlinearly, by a fly parasitoid that modifies the competitive ability of one of the species. Using this arrangement as a template, we explore the dynamical consequences with a simple ordinary differential equation (ODE) model. Results are complicated and include alternative periodic and chaotic attractors. The qualitative structures of those complications, however, may be approximately retrieved from the basic natural history of the system.

In this work, the results of a survey for species of Fluda Peckham & Peckham, 1892 in primary forest in five Bolivian forest ecoregions are reported. Fluda dauca sp. nov. is described from Southwest Amazon forest and F. thuruampara sp. nov. from Bolivian Yungas forest. Fluda perdita (Peckham & Peckham, 1892) is reported from Bolivia for the first time. Both new species exhibited polymorphic mimicry; dark females of both species resembled the turtle ant Cephalotes pusillus (Klug, 1824) and dark males of F. thuruampara sp. nov. the carpenter ant Camponotus sanctaefidei Dalla Torre, 1892. Orange males and females of F. dauca sp. nov. are likely mimics of Camponotus latangulus Roger, 1863. Males of Fluda may compensate lower mimetic accuracy by the broadened femora I, resembling an ant head in lateral view and ant mandibles when moving the face towards a potential threat. As in other Simonellini, the turnover of Fluda species between the South American superregions suggests that significant shifts in seasonality and related conditions are major factors triggering speciation in the tribe Simonellini.

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Background. Anaphylaxis is a life-threatening hypersensitivity reaction. The present study aimed to investigate the cases of anaphylaxis to ant stings in Iran to determine the characteristics of patients, geographical distribution and the type of ants that cause anaphylaxis. Methods. Patients with a history of anaphylaxis to ant sting underwent skin allergy test with extracted substance from Solenopsis invicta. Samples of ants were collected from the sites where each patient was bitten and their species were identified by a medical entomologist. Results. Nineteen patients (mean age: 26.2 years; range: 4-48 years) were included in the study. Most patients (89.5 percent) were female. The lower limb was the most common site of the sting and most stings had occurred in the morning (31.6 %) and evening (31.6%). Skin manifestations were the most common clinical symptoms (94.7%). Most cases of stings were observed in the Hormozgan province (89.5%) located in southern Iran. Sixteen patients had positive skin prick test for ant venom. All collected ants that caused anaphylaxis belonged to the Pachycondyla sennaarensis species. Conclusions. Ant sting anaphylaxis is not uncommon in Iran, especially in its southern regions. All cases of anaphylaxis in this study were due to samsum ant sting (Pachycondyla sennaarensis), which is a species similar to the fire ant (Solenopsis invicta). Allergy skin testing with fire ant extract was positive and helpful in identifying samsum ant allergy in all cases.

The case involved a man in his forties. While working at the restaurant that the patient runs, the patient experienced a stab-like pain on the left shoulder and developed systemic pruritic eruptions. He was diagnosed with anaphylaxis upon visiting our emergency department. Conjunctival hyperemia, lip swelling, cold sweats, and nausea presented later. A cap fluorescence enzyme immunoassay using the serum of the patient showed specific immunoglobulin E (IgE) positivity for wasps; therefore, we hypothesized that he had anaphylaxis caused by the insect\'s sting. Insects of the same species as that by which the patient had been stung were collected and finally identified as the Asian needle ant (Brachyponera chinensis). The freeze-dried insects\' bodies were sonicated into powders and stored for following examinations. Next, a basophil activation test was performed using the patient\'s whole blood treated with the reagent above, which showed positivity. Furthermore, a skin prick test using the same reagent showed a positive result, and the reaction increased in a concentrationdependent manner. Based on these results, the patient was diagnosed with anaphylaxis after a sting by the ant. Based on the results of the allergen component specific IgE test, we speculated that the pathogens in this case was group5 allergen of the Asian needle ant. Anaphylaxis following insect stings by this ant has been reported frequently in South Korea. However, it is quite rare in Japan, although the ant is native to Japan. Clinicians should consider that this allergy can occur indoors, unlike allergies to other types of venom.

Species delimitation offered by DNA-based approaches can provide important insights into the natural history and diversity of species, but the cogency of such processes is limited without multigene phylogenies. Recent attempts to barcode various Solenopsidini ant taxa (Hymenoptera: Formicidae: Myrmicinae), including the thief ant Solenopsis saudiensis Sharaf & Aldawood, 2011 described from the Kingdom of Saudi Arabia (KSA), were precipitated by the unexpected existence of a closely related species, the Nearctic S. abdita Thompson, 1989 within the S. molesta species complex native to Florida. This finding left the species status of the former uncertain. Here, we investigated the taxonomy and phylogeny of these two species to determine whether or not S. abdita represents a new global tramp species. We inferred a phylogeny of the two species using DNA sequence data from four nuclear genes (Abd-A, EF1α-F1, EF1α-F2, and Wingless) and one mitochondrial gene (COI) sampled from populations in Florida, Guatemala, Hawaii, and Saudi Arabia. Both species clustered into one distinct and robust clade. The taxonomy of S. saudiensis was re-examined using morphometrics. A reassessment of the morphological characters used to diagnose the worker and queen castes were consistent with molecular evidence. Based on combined morphological and molecular evidences S. saudiensis is declared as a junior synonym of S. abdita (syn. nov.). In addition, our findings indicate that S. abdita is a novel global tramp species which has a far wider distribution than previously thought and has established itself in many new habitats and different geographic realms.

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