Euploea core, also known as the common crow, is a common butterfly found in South Asia to Australia. In India it is also sometimes referred to as the common Indian crow, and in Australia as the Australian crow. It belongs to the crows and tigers subfamily Danainae (tribe Danaini).

E. core is a glossy-black, medium-sized 85–95 mm (3.3–3.7 in) butterfly with rows of white spots on the margins of its wings. E. core is a slow, steady flier. Due to its unpalatability it is usually observed gliding through the air with a minimum of effort. As caterpillars, this species sequesters toxins from its food plant which are passed on from larva to pupa to the adult. While feeding, it is a very bold butterfly, taking a long time at each bunch of flowers. It can also be found mud-puddling with others of its species and often in mixed groups. The males of this species visit plants like Crotalaria and Heliotropium to replenish pheromone stocks which are used to attract a female during courtship.

The common crow is the most common representative of its genus, Euploea. Like the tigers (genus Danaus), the crows are inedible and thus mimicked by other Indian butterflies (see Batesian mimicry). In addition, the Indian species of the genus Euploea show another kind of mimicry, Müllerian mimicry. Accordingly, this species has been studied in greater detail than other members of its genus in India.

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