Protesilaus earis, the Rothschild's swordtail, is a species of butterfly found in the Neotropical realm (southeast Brazil, Paraguay, Argentina).

Antenna dark yellowish brown.

Wings slightly yellowish, beneath slightly reddish; bands narrow, 4. band of the forewing reduced to a small spot, 6. band close to the lower angle of the cell; the yellowish marginal and submarginal spots of the hindwing narrow, above and beneath smaller than in the name-typical protesilaus; hindwing beneath with long arrow-shaped patch before the abdominal margin, this patch reduced in protesilaus.

Dorsal margin of the harpe slightly widened, ventral process non-dentate, not extending to the lower edge of the clasper, central process short, broad, spatulate, strongly dentate.

Eastern Ecuador, widely distributed.