Morphology and phenology of sexuals and new distribution data on the blind Mediterranean ant Hypoponera abeillei (Hymenoptera, Formicidae)

Hypoponera abeillei is the sole member of the otherwise exclusively Afrotropical abeillei group to occur in the West-Palearctic and since its first description on the basis of two Corsican workers in 1881, it remained little-known. Workers of this species are thought to entirely lack eyes, a rare trait among ants of the region, yet their lifestyle remains undocumented. On the other hand, the male caste has been described from 4 Tunisian specimens in 1921, and queens remained so far undescribed. We present an updated description of the male caste based on 45 specimens and a first description of the queen caste based on 14 specimens. The H. abeillei material we examined comes from Italy, Spain and Malta (mostly originating from coastal localities), and comprises 11 inedit distribution records, including the first findings in the islands of Mallorca, Malta and Sardinia. Moreover, we provide a first phenological overview of the species’ nuptial flights. Our data show that H. abeillei sexuals flight during the summer, mostly in August, and demonstrate that they can easily be distinguished from all the other Hypoponera species inhabiting the Mediterranean region based on their morphology. The remarkable diversity of Mediterranean Hypoponera males and queens suggest that sexuals may have a role in future attempts to understand relationships within this genus, yet the number of species in which sexual castes are documented is still extremely reduced.

Formica rufa ants have a limited effect on the abundance of the parasitic fly Ernestia rudis in Scots pine plantations

Red wood ants (the Formica rufa group) are important predators which affect animal communities in their territory. Therefore, they are useful in forest protection. On the other hand, they also prey on beneficial organisms. We have asked whether Formica rufa L. affects the abundance of the parasitic flies Ernestia rudis (Fallén). Ten anthills situated in about 40-year- old pine plantations were used for the study. The presence of E. rudis cocoons was assessed in eight soil samples excavated in the surrounding of each nest at a distance of 2–17 m. Our results show a considerably lower abundance of E. rudis only to 4.5 m from the nests. The occurrence of Formica rufa ants therefore had no significant effect on the beneficial E. rudis population in plantation forests, where ants populations are low.

Population and Nesting Behaviour of Weaver Ants, Oecophylla smaragdina from Meghalaya, India

Weaver ants are known for their unique nest-building skills using leaves and larval-silk as a binding agent. The weaver ants, Oecophylla smaragdina are present in large numbers in the Ri-Bhoi district, Meghalaya. Ri-Bhoi district is a hot and humid place with 22 -30°C. This is the first study from this region to examine the nesting behavior along with the population of these ants from here. It was noted that they build nests in different types of trees but it is more abundant in needlewood trees (Schima wallichi) locally known as ‘diengngan.’ From the central trunk of the S. wallichi tree, the nearest distance of the nest is about 0.7 m and the farthest up to 3.4 m. The nests of O. smaragdina are somewhat round-oval and use leaves of different sizes ranging from 8-32 cm2. The nests are made at a height ranging from 4-25 m and their average nest size is about 9,483 cm3. They utilize about twenty leaves with a specific number of chambers to keep their broods, the queen, and food. The number of worker ants, pupae, and larvae are variable in different nests because of nest size, location/height of the nests, and the trees. When the nest population increases, they locate a new spot and build a satellite nest where they get the right amount of sunlight and shelter from predators and adverse environmental factors. These weaver ants are also used as medicine, food and fish bait by the indigenous people in Meghalaya.

Negative effects of ant-plant interaction on pollination: costs of a mutualism

The mutualism of ants and extrafloral nectary (EFN)-bearing plants is known to reduce rates of herbivory. However, ants may have negative impacts on other mutualisms such as pollination, constituting an indirect cost of a facultative mutualism. For instance, when foraging on or close to reproductive plant parts ants might attack pollinators or inhibit their visits. We tested the hypothesis that ants on EFN-bearing plants may negatively influence pollinator behavior, ultimately reducing plant fitness (fruit set). The study was done in a reserve at Brazilian savannah using the EFN-bearing plant Banisteriopsis malifolia (Malpighiaceae). The experimental manipulation was carried out with four groups: control (free visitation of ants), without ants (ant-free branches), artificial ants (isolated branches with artificial ants on flowers) and plastic circles (isolated branches with plastic circles on flowers). We made observations on flower visitors and their interactions, and measured fruit formation as a proxy for plant fitness. Our results showed that pollinators hesitated to visit flowers with artificial ants, negatively affecting pollination, but did not hesitate to visit flowers with plastic circles, suggesting that they recognize the specific morphology of the ants. Pollinators spent more time per flower on the ant-free branches, and the fruiting rate was lower in the group with artificial ants. Our results confirm an indirect cost in this facultative mutualism, where the balance between these negative and positive effects of ants on EFN-bearing plants are not well known.

Coconut shell traps: easiest and economic way to attract stingless bees (Tetragonula iridipennis) Smith

The trap occupancy rate and colony development parameters of swarms of stingless bee, Tetragonula iridipennis in coconut shell traps was studied in the research farm of ICAR-National Bureau of Agricultural Insect Resources (NBAIR) Bengaluru, Yelahanka campus Karnataka, India. The trap occupancy rate by the stingless bees was 44.87% in a time period of 13.40 ± 4.38 days. New cells were constructed by the bees in 12.10 ± 2.13 days. The number of honey and pollen pots filled was 15.60 ± 3.92 and 6.61 ± 2.95, respectively. The brood cells were constructed 89.50 ± 6.07 days after acceptance of the shell traps with an average of 67.70 ± 20.83 brood cells per trap. The foragers preferred foraging for nectar, resin and pollen during the 15, 30 and 45 days after acceptance of the coconut shells for nesting. Coconut shell traps are easiest and economic way of trapping the swarming population of stingless bees.

Dispersal of Phraortes illepidus (Phasmida: Phasmatidae) Eggs by Workers of the Queenless Ant, Pristomyrmex punctatus (Hymenoptera: Formicidae)

Eggs of some stick insects bear external appendages called capitula. Foraging worker ants attracted by capitula disperse eggs in a response similar to the responses of workers to elaiosome-bearing seeds of many plants. For this study, we conducted rearing experiments in the laboratory to elucidate the interspecific relation between the queenless ant, Pristomyrmex punctatus Smith, and the stick insect, Phraortes illepidus (Brunner von Wattenwyl) of which eggs bear capitula. Eggs of P. illepidus were proposed to P. punctatus in the laboratory. Capitula were removed from most of the eggs not only when ants were starved but also when ants were well-fed. In large rearing containers, eggs were transported by ants from their place of origin. Many eggs were transferred horizontally on the surface. Although some eggs were found in the artificial ant nests, it is likely that stick insects are not in active ant nests at the time of hatching in nature because of P. punctatus nest-moving habits. The percentage of eggs buried in the sand was small. Furthermore, most of the buried eggs were found at less than 3 cm depth. Results show that many P. illepidus hatchlings can reach host plants safely without being attacked by ant workers. These results suggest that P. punctatus can be a good partner of P. illepidus. Ants disperse eggs of slow-moving stink insects in exchange for some nutrition from capitula.

Social Parasite Ants in the Alps: a New Site of the Vulnerable Myrmica myrmicoxena and New Uppermost Altitudinal Limit for M. microrubra

We conducted a survey on the Alpine fauna of one of the largest Natural Park of the Italian Alps (Stelvio National Park) in the framework of a broad ecological monitoring of Alpine biodiversity. A two-years standardized sampling employing pitfall traps along a 1200 m altitudinal gradient led to the discovery of two interesting inquiline social parasite ants of the genus Myrmica: M. myrmicoxena Forel, 1895 and M. microrubra Seifert, 1993. Myrmica myrmicoxena, which is classified as Vulnerable according to the IUCN Red List, was so far known from only three sites across a narrow geographic range between Italy and Switzerland. Our data support the previous hypothesis over its ecology and host association. Myrmica microrubra is considered an incipient species of high evolutionary interest, sometimes regarded as an intraspecific form of M. rubra. While having a wide distribution in Europe, its presence in Italy was hitherto known only from a single site, and our record extends its altitudinal distribution limit in Europe upwards by about 600 m.

Nesting Biology of the Solitary Ground-Nesting Bee Diadasina riparia (Apidae: Emphorini)

We described the nesting behavior and ecology of Diadasina riparia, from an urban dry forest fragment. The nests of D. riparia were shallow with circular entrance, closed by a mud plug, from which a straight vertical tunnel ending in one or more brood cells. Most females need one day for construction and provisioning the nest. The natural enemies were flies of Anthrax genus, the cleptoparasitic bees Leiopodus trochantericus, and Mutillidae wasp. The feature about the life history, nest architecture, materials used, pollen provisions behavior and associated organisms of this species allow the comparison with other emphorines species.

Taxonomic Partition Suggests a High Degree of Coevolution Between Termites and Their Termitophiles

Termites have a tight interaction with their social parasitic Corotocini beetles. This association is thought to be mainly host-specific, despite some host-switch events. By analyzing the taxonomic partition between species and genera of Corotocini, we propose the hypothesis that the main driver of the diversity of these termitophiles is coevolution.

Ant Rafting in an Extreme Ecosystem

Ants are among the most abundant organisms on Earth, being adapted for living on different solid surfaces. However, in some habitats, like riparian forests and flooded plains, water can be a constant obstacle, and overcoming this obstacle can be essential to determine the persistence of ants in such habitats. While most ant species avoid the water during a flood by foraging at higher elevations or climbing on trees, a few species developed ways to overcome this obstacle by swimming. Here, we report, for the first time, ants of the species Linepthema micans (Forel 1908) performing rafts. We observed 14 rafts in three consecutive days at approximately 1400 meters a.s.l. in Serra do Cipó, Brazil. Notably, this is the first record of ant rafting in tropical mountaintop grasslands, which are extreme habitats with shallow and sandy soils, and where small temporary water pools are extremely common in the wet season.