Deep within a cave in Brazil, a crusty creature crawled along the moist, rocky ground. Something about the subterranean animal caught the attention of nearby scientists. The scientists were surveying wildlife in the reddish, iron-rich cave system of the Carajás Mountains, according to a study published Sept. 13 in the journal Zoosystema. These “extensive surveys” took place between 2005 to 2019, “resulting in a considerable amount of material available for study.” During these cave surveys, scientists collected over 1,300 millipedes and preserved the specimens in museum collections but did not...