A member of the genus Myrmecia in the subfamily Myrmeciinae, it was first described by American entomologist Walter Cecil Crawley in 1925.

Queens and workers share similar morphological features, but they can be distinguished by the noticeable size difference.

Myrmecia regularis is found in the south-western coastal regions, inhabiting eucalypt woodland and open forests.

Workers are active during the day and night, foraging on trees in search for prey and sweet substances such as sap and nectar.

[4] Clark's reasons for this were unknown, and William Morton Wheeler revived the species from synonymy, stating that specimens he and W.S.

They assigned M. regularis to the M. gulosa species group, based on the morphological characters of worker ants.

[5] Owing to the rugose sculpture of the head and thorax, M. regularis is noticeably smaller than M. forficata.

The mandibles of M. regularis are much narrower, the posterior corners of the head are more round and the petiolar peduncle is longer.

The mandibles appear to be deep red, and some areas, such as the gastric segments, are golden brown.

[5] M. regularis colonies do not form mounds, but rather nest in damp, black soil or under large stones and logs with 100 to 200 workers present.

[11] Excavated incipient nests (young colonies beginning to develop) show small chambers 2.5 to 4 cm (0.98 to 1.57 in) wide, where logs and stones form the roof of the cell.

[5] Myrmecia regularis is a highly aggressive ant that will pursue any intruder to a distance of 1.8–2.7 metres (2–3 yards) if their nests are disturbed.

[8] All stages of the frog Metacrinia nichollsi are known to dwell inside M. regularis colonies, where they use several galleries constructed by the ants.

[5] Queens are most likely fertilised by males sometime between February and April; however, scientists have seen alates engage in nuptial flight during March.

[16][17] After nuptial flight, a queen will isolate herself and form a small chamber underground, where she remains for seven to eight months.

During this time, the queen may emerge from her nest occasionally, but she will only lay eggs from October to November when there is a rich supply of food.