Arthropods visiting flowers of Aristolochia californica Torr. (Aristolochiaceae)

A  survey  of   arthropods  visiting  flowers  of California  pipevine,  Aristolochia  californica Torr. (Aristolochiaceae), was conducted during 2017 and 2018. Collecting produced 1725 individuals in 75 terminal taxa. Over the two years, a residential backyard produced more terminal taxa (70) and individuals (1539) than flowers in an upland grassland (27 terminal taxa, 186 individuals). Diptera: Mycetophilidae were the dominate arthropod group attracted to the flowers, accounting for 77.8% of  visitors and represented by 17 genera and 28 morphospecies, with Mycetophila  Meigen,  1803  being  most  diverse  with  12  morphospecies.  The  superfamily  Sciaroidea  (Keroplatidae,  Mycetophilidae,  Sciaridae)  had  33  morphospecies  and  1505  specimens  representing  87.2%  of   the  total  arthropods.  The  arthropods  could  be  grouped  into  the  following guilds: potential pollinators, fluid feeders, predators, parasites, scavengers and temporary residents.