Thermal Tolerances of Three Tramp Ant Species (Hymenoptera: Formicidae)

Abstract

Tramp ant species present a set of adaptations to their urban habitats, and there is a paucity of knowledge about how they interact with abiotic factors, like temperature. Temperature is well known to interfere with insect activity. The present study evaluated the temperature tolerance of three important tramp ant species: Monomorium floricola ( Jerdon), Monomorium pharaonis (Linnaeus) and Tetramorium bicarinatum (Nylander). Tested temperatures were 0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48 and 50.C. Ten repetitions with 20 workers each were done with each temperature and analyzed species. The number of dead workers was recorded every hour over a total of 8 hours. All procedures were done using thermal incubators at relative humidity within 50-95%. Workers of M. pharaonis proved more tolerant to high temperatures (30-50.C) than workers of M. floricola and T. bicarinatum. The higher the temperatures tested, greater was the recorded ant mortality, with temperature 50.C being fatal to all species after 1h of exposition. The least tolerant species to temperatures below 20.C was T. bicarinatum. Low temperatures tested were not fatal to any of the tested species.

Molecular adaptations to heat stress in the thermophilic ant genus Cataglyphis

“…All these species display a lower heat tolerance compared with Cataglyphis. Similar thermal tolerance to Cataglyphis has been reported in Monomorium pharaonis, M. floricola and Tetramorium bicarinatum (Solis & Bueno, 2012). In the desert ants Pogonomyrmex rugosus and P. barbatus, 50% of alate females reportedly survive for 2 h at 47℃ (Johnson 2000).…”

Facing lethal temperatures: heat shock response in desert and temperate ants

“…We characterized and compared the heat tolerance and the heat stress transcriptomic response of four ecological equivalents desert ant species from three distinct genera, and of two outgroup species living in a temperate region. From all 6 studied species, the red honey ant Melophorus bagoti was the most heat tolerant, withstanding the highest temperatures ever reported in ants (Johnson, 2008;Solis & Bueno, 2012;Andrew et al, 2013;Perez et al, 2021).…”

“…We characterized and compared the heat tolerance and the heat stress transcriptomic response of four ecological equivalent desert ant species from three distinct genera, and of two outgroup species living in a temperate region. From all 6 studied species, the red honey ant Melophorus bagoti was the most heat tolerant, withstanding the highest temperatures ever reported in ants [10,[32][33][34]. However, in natural habitats, the Sahara silver ant Cataglyphis bombycina is the species known to endure the most environmental heat, with a mean temperature in the warmest quarter of 30.8 o C and maximum temperature of 42.3 o C (Table S1).…”

Facing lethal temperatures: Heat‐shock response in desert and temperate ants

“…We characterized and compared the heat tolerance and the heat stress transcriptomic response of four ecological equivalent desert ant species from three distinct genera, and of two outgroup species living in a temperate region. From all six studied species, the red honey ant M. bagoti was the most heat-tolerant, withstanding the highest temperatures ever reported in ants (Andrew et al, 2013;Johnson & Stahlschmidt, 2020;Perez et al, 2021;Solis & Bueno, 2012). However, in natural habitats, the Sahara silver ant C. bombycina is the species known to endure the most environmental heat, with a mean temperature in the warmest quarter of 30.8°C and a maximum temperature of 42.3°C (Table 1).…”