Thyanta pallidovirens

No row of spots on the underside (left T. pallidovirens , right: T. custator accerra ), although row of spots may be absent in southwestern T. custator accerra spinosa form , making this less useful in areas like southern California. (Although the spinosa form should also have more prominent humeral spines, making it a bit easier to differentiate.) . It should be noted that there are sometimes small black spots present in pallidovirens, but they are typically smaller than the adjacent spiracle. This feature should be used with caution and any photo ID of subgenus Thyanta in areas where the two species overlap should be considered tentative. Shoulder spine blunt, or missing entirely, unlike some T. custator accerra . In 1957, Ruckes separated Thyanta pallidovirens into four subspecies : Thyanta pallidovirens pallidovirens from the western US, Thyanta pallidovirens accerra from the eastern US, Thyanta pallidovirens spinosa from the southwestern US, and Thyanta pallidovirens setosa largely from the Great Basin . Chromosomal studies and cross-breeding experiments have determined that the males of T. pallidovirens pallidovirens and T. pallidovirens setosa have a chromosome count of 14 + XY while those of T. pallidovirens spinosa and T. pallidovirens accerra ) have a count of 16 + XY . Now, T. pallidovirens pallidovirens and T. pallidovirens setosa fall under Thyanta pallidovirens while T. pallidovirens accerra and T. pallidovirens spinosa fall under Thyanta custator accerra .