The full distribution of Nothomyrmecia has never been assessed, and it is unknown how widespread the species truly is; its potential range may be wider if it does favour old-growth mallee woodland.

Nothomyrmecia is most active when it is cold because workers encounter fewer competitors and predators such as Camponotus and Iridomyrmex, and it also increases hunting success.

Workers are strictly nocturnal and are solitary foragers, collecting arthropod prey and sweet substances such as honeydew from scale insects and other Hemiptera.

Some entomologists have suggested a relationship to the Baltic Eocene fossil ant genus Prionomyrmex based on morphological similarities, but this interpretation is not widely accepted by the entomological community.

Owing to its body structure, Nothomyrmecia is regarded to be the most plesiomorphic ant alive and a 'living fossil', stimulating studies on its morphology, behaviour, ecology, and chromosomes.

The larvae bear a primitive body structure with no specialised tubercles, sharing similar characteristics with the subfamily Ponerinae, but the sensilla are more abundant on the mouthparts.

[12] The cocoons have thin walls and produce meconium (a metabolic waste product expelled through the anal opening after an insect emerges from its pupal stage).

The morphology of the abdomen, mandibles, gonoforceps (a sclerite, serving as the base of the ovipositors sheath) and basal hamuli show it is more primitive than Myrmecia.

Equally, wing-reduction might be a feature that only forms in drought-stressed colonies, as has been observed in several Monomorium ant species found throughout semi-arid regions of Australia.

[4] Entomologist Robert W. Taylor subsequently expressed doubt about the accuracy of recording of the original discovery site, stating the specimens were probably collected from the western end of the Great Australian Bight, south from Balladonia.

[2] The discovery of Nothomyrmecia and the appearance of its unique body structure led scientists in 1951 to initiate a series of searches to find the ant in Western Australia.

[6] Over three decades, teams of Australian and American collectors failed to re-find it; entomologists such as E. O. Wilson and William Brown, Jr., made attempts to search for it, but neither was successful.

[14] Then, on 22 October 1977, Taylor and his party of entomologists from Canberra serendipitously discovered a solitary worker ant at Poochera, South Australia, southeast of Ceduna, some 1,300 km (810 mi) from the reported site of the 1931 discovery.

[17][18] In 1934 entomologist John S. Clark published a formal description of Nothomyrmecia macrops as a new species and within a completely new genus and tribe (Nothomyrmecii) of the Ponerinae.

[4] He did so because the two specimens (which then became the syntypes) bore no resemblance to any ant species he knew of, but they did share similar morphological characteristics with the extinct genus Prionomyrmex.

Clark notes that the head and mandibles of Nothomyrmecia and Prionomyrmex are somewhat similar, but the two can be distinguished by the appearance of the node (a segment between the mesosoma and gaster).

[19] This proposal was rejected by American entomologist William Brown Jr., who placed it in the subfamily Myrmeciinae with Myrmecia and Prionomyrmex, under the tribe Nothomyrmeciini.

[25] In the same year, American entomologists P. S. Ward and S. G. Brady reached the same conclusion as Dlussky and Perfilieva and provided strong support for the monophyly of Prionomyrmex.

[2][36] Genetic evidence suggests that the age of the most recent common ancestor for Nothomyrmecia and Myrmecia is approximately 74 million years old, giving a likely origin in the Cretaceous.

[37] Nothomyrmecia and other primitive ant genera such as Amblyopone and Myrmecia exhibit behaviour similar to a clade of soil-dwelling families of vespoid wasps.

[38] The following cladogram generated by Canadian entomologist S. B. Archibald and his colleagues shows the possible phylogenetic position of Nothomyrmecia among some ants of the subfamily Myrmeciinae.

[2] Nest entrance holes are difficult to detect as they are only 4–6 mm (0.16–0.24 in) in width, and are located under shallow leaf litter with no mounds or soil deposits present; guards are regularly seen.

[2] The workers search for prey in piles of leaves, killing small arthropods including Drosophila flies, microlepidopterans and spiderlings.

Workers are possibly most active when it is cold because at these times they encounter fewer and less aggressive competitors, including other more dominant diurnal ant species that are sometimes found foraging during warm nights.

[46] Unless a forager has captured prey, workers stay on trees for the remainder of the night until dawn, possibly relying on sunlight to navigate back to their nest.

Adopting a posture by opening the jaws in a threatening stance or deliberately falling onto the ground and remaining motionless until the threat subsides are two known methods.

[54] This uncertainty results from the suggestion that, because some colonies have been shown to have high levels of genetic diversity, worker ants could be inseminated by males and act as supplementary reproductives.

[40] Suspected anthropogenic threats that can significantly affect Nothomyrmecia include habitat destruction and fragmentation by railway lines, roads and wheat fields.

[3] Bushfires are another major threat to the survival of Nothomyrmecia, potentially destroying valuable food sources, including the trees they forage on, and reducing the population of a colony.

[33] Conservationists suggest that conducting surveys, maintaining known populations through habitat protection and fighting climate change may ensure the survival of Nothomyrmecia.