Cactus Sap Beetle
Nitops (Carpophilus) pallipennis (?)
Observed at White Tank Mountain Park, Maricopa Co., Arizona. April 2019. Many adults were inside the flowers and many developing larvae were found in the old, withered flower buds of Buckhorn Cholla.
Nitidulidae -- Sap Beetle Family
Many species of sap beetle (Nitidulidae) are inhabitants of the Sonoran Desert. Most are around 2 to 4 mm in length. Cactus fruits that have fallen or are broken open will attract the adults which may lay eggs that develop into larvae (grubs). Many others are found in the large flowers of cacti where they and their young larvae feed on pollen and other parts of the flower. The beetle at left is joined by a Forelius ant in taking a sweet exudate from the surface of an unopened cholla flower bud. Domestic species can be a pest of dried or over-ripe fruits.
