The Desert Marble belongs to the family Pieridae, a large worldwide family of butterflies which includes the whites, sulphurs, marbles and orangetips. Butterflies in this family bear a full complement of six functional legs and are typically medium-sized species which spend much time on the wing. Although some species are common or abundant they are often flighty and difficult to approach. Pierids typically have white or yellow wings, and can be very similar in appearance worldwide. In Washington there are 17 species of pierids including 7 sulphurs, 7 whites, 2 marbles and 1 orangetip.

The Desert Marble ranges from southern BC to northern Mexico, occurring east of the Rocky Mountains but largely absent in coastal areas. In Washington it occurs east of the Cascades in the shrub steppe, especially in hilly habitats. It is univoltine (single-brooded), appearing early in the season and flying late March to late June, and is sometimes common in the Columbia Basin and adjacent areas. Males emerge before females and patrol gullies and hillsides for mates. Males hilltop in April, females joining them to mate before returning to lower slopes to lay their eggs. Females are usually found flying near host plants but are elusive and easily disturbed. Both sexes visit flowers including phlox, mustards and fiddlenecks.

Pupae overwinter, adults eclosing the following spring. Females lay eggs singly on the buds, flowers, stems or leaves of the host plant. Larval hosts are crucifers including several species of Arabis or Bouchera (rockcress), Sisymbrium altissimum (Tumble Mustard), Descurainia pinnata (Tansy mustard) and Lepidium sp. (peppergrass). Larvae feed on all parts of the host, preferring terminal stems, buds and flowers early but feeding readily on leaves as they grow larger. Development is rapid, likely due to the ephemeral nature of many of the mustard hosts in arid areas in late spring. Larvae are green with a vivid lateral white stripe, sometimes slightly edged above in darker purple; the white stripe runs the full length of the larva but does not continue onto the head. There are five larval instars. Larvae wander before pupation, which occurs mostly on host stems. The pupa is light brown and streamlined with a long beak; after a few weeks it turns dark brown. The chemistry of droplets produced by setae in L1-L4 is unknown but is presumed to be for defensive purposes. No nests are made, and survival is based on camouflage and defensive chemicals. In the later instars the only larva likely to be confused with this species in Washington is Anthocharis sara (Sara Orangetip) which is also green with a prominent lateral white stripe. However the white side stripe in A. sara continues onto the head, providing an easily observed identification mark.

In Washington the adult Desert Marble can be confused only with the Large Marble, Euchloe ausonides. The two species differ in size, E. ausonides being significantly larger. Also the ventral hindwing coloration of E. ausonides is distinctly gold while in E. lotta it is a colder green with limited gold veins. Euchloe lotta usually flies a little earlier where the two occur together, and E. ausonides continues later into the season and at higher elevations.

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