Aquatic insects as umbrella species for ecosystem protection in Death Valley National Park

Under the United States Endangered Species Act (ESA), critical habitat for listed species is also protected. Many aquatic insects protected under the ESA are habitat-restricted, mainly to springs. Some of these species do not co-occur with ostensibly more charismatic vertebrates, and have the potential to act as umbrella species for aquatic ecosystems. We suggest that the flightless creeping water bug Ambrysus funebris La Rivers (Insecta: Heteroptera: Naucoridae) has the potential to be such a species. Endemic to a spring system in Death Valley National Park, it co-occurs with eight other endemic aquatic invertebrate species, but with no vertebrates. Therefore, its protection would facilitate protection of this desert oasis. Ambrysus funebris is a candidate for protection under the ESA because of its endemicity, a decline in abundance, and habitat degradation. To facilitate its use as an umbrella species, we report the first illustrated descriptions of the five nymphal instars of Ambrysus funebris La Rivers. Recommendations on its conservation and role as an umbrella species for conserving its habitat are presented. A synopsis of aquatic insect species protected or listed as candidates under the ESA indicates that spring-endemics predominate. We also present a list of potentially threatened and unprotected aquatic heteropterans in the western United States.