Winter Stoneflies (Plecoptera) in Seasonal Habitats in New Mexico, USA
Seasonal stream habitats in New Mexico supported 10 species of winter-emerging stoneflies. Winter precipitation in combination with low winter temperatures created a seasonal moisture surplus and seasonal streamflow in this semi-arid region. Study area streams were dry for long periods in spring and autumn. Two different types of seasonal (ahyporheic) habitats were identified. Small high mountain streams fed by seasonal snowmelt runoff (type M) were inhabited by Capnia decepta, Eucapnopsis brevicauda, Isocapnia vedderensis, Capnia californica, Capnura wanica, Mesocapnia werneri, Taenionema jacobii, and Capnura fibula. Mesocapnia arizonensis and M. frisoni seemed to specialize in low-elevation watercourses fed by winter rains and rising water tables (type L). Adaptations for survival during spring and autumn periods of no streamflow, desiccation, or flash flooding include small size, rapid development, and diapause during egg or larval stages.