Tibicen neomexicensis sp. n., a new species of cicada found in the Sacramento Mountains of southcentral New Mexico, is described. T. neomexicensis closely resembles T. chiricahua Davis morphologically, but males of the two species have highly distinct calling songs that differ in phrasal structure, amplitude burst rates, and pulse structure. Unlike T. chiricahua, male T. neomexicensis use conspicuous dorso-ventral abdominal movements to modulate the amplitude and frequency of their calls. T. neomexicensis is also smaller on average than T. chiricahua, and differences in the color patterns of the wing venation identify these two species morphologically. Both species are dependent on pinyon-juniper woodlands and have similar emergence phenologies. These species appear to be allopatric, with T. chiricahua found west of the Rio Grande in New Mexico, Arizona, and Mexico, and T. neomexicensis so far known only from New Mexico, east of the Rio Grande. T. chiricahua and T. neomexicensis males share a common genitalic structure that separates them from all other species of Tibicen, and the possible evolutionary and biogeographic history of these likely sister species is also discussed.
