The Quino checkerspot (Euphydryas editha quino) is a butterfly native to southern California and northwestern Baja California. It is a subspecies of the common Edith's checkerspot (Euphydryas editha) and the second such subspecies to be listed under the federal Endangered Species Act.

This taxon, like many others, has undergone several changes in nomenclature and classification. It was originally described as Melitaea quino in 1863 by Hans Hermann Behr, based on specimens collected by Dr. Cooper in San Diego, and was named after Eusebio Kino, or "Padre Quino, the first European that ever succeeded in erecting a permanent settlement in California, and at the same time contributed very considerably by his learned writings to a more exact knowledge of these then scarcely discovered regions." In 1929 it was reduced to a subspecies of Euphydryas chalcedona. In 1998 it was concluded through Behr's 1863 description that it should be classified as E. editha, not E. chalcedona. Moreover, the subspecies E. editha wrighti was demoted to a junior synonym for E. editha quino.

A member of the brush-footed butterfly family, Nymphalidae, the Quino checkerspot is a medium-sized butterfly with a wingspan of approximately 3 cm. The dorsal wing surfaces are a colorful checkerboard of brown, red and yellow spots. The Quino differs from other E. editha subspecies in that its spots tend to be a darker red.

It also differentiates itself through its size and larval and pupal phenotypes. The ventral side of the butterfly are dominated by a checkered red and cream pattern. Its abdomen has red stripes across the dorsal side. After a second molt, the Quino checkerspot is recognized by the dark black coloration and row of 8 to 9 orange tubercles on their back. Before the larvae first molt they are mostly yellowish. After first molt and before their second molt they are gray with black markings. The pupae are mottled black on a blue-gray background.

The Quino checkerspot is easily confused in the field by inexperienced butterfly searchers. It is generally confused with three other co-occurring butterfly species, the Chalcedon or variable checkerspot (Euphydryas chalcedona), Gabb's checkerspot (Chlosyne gabbii) and Wright's checkerspot (Thessalia leonira wrighti).

The life cycle of the Quino checkerspot closely mirrors that of the close Bay checkerspot. They share the same host plant and similar chronology of developmental stages. Sometimes, organisms molt seven times before reaching adulthood. There are typically only one generation of adults every year. The flight period is between February through May.

Female butterflies only lay eggs on species they recognize as host plants. The larval food sources for the Quino checkerspot butterfly are:

Larval Quino checkerspot butterfly may also use other species of native plantain (Plantago sp.), as well as purple owl’s clover (Castilleja exserta) and thread-leaved bird's beak (Cordylanthus rigidus), as secondary host plants. The use of purple owl's clover and thread-leaved bird’s beak is rare. These species alone do not support Quino breeding.