Illustrated review of Mormon cricket Anabrus simplex (Tettigoniidae, Tettigoniinae) embryonic development

Mormon crickets Anabrus simplex Haldeman, 1852 are a pest of crops and rangeland in the western United States, but little is known about their development in the egg stage. Mormon crickets have multiple states at which they may diapause and thus affect population growth. Consequently, a series of photographs of Mormon cricket embryonic stages was organized using published research on Old World katydids. Earlier stages were more difficult to distinguish without removing the chorion. However, where possible, features that can be seen through the chorion are indicated with the expectation that these will be useful in characterizing development in living embryos. As with other Orthoptera, the timing of development varied greatly among individuals, but at a minimum, embryos filled approximately half the egg in six weeks, whereas they required 12 weeks from oviposition to reach the final stage before their obligate winter diapause.