Life cycle and behaviour of Charoxus spinifer and Charoxus major (Coleoptera: Staphylinidae: Aleocharinae), predators of fig wasps (Hymenoptera: Agaonidae)

Abstract

Charoxus spinifer is associated in southern Florida with native fig trees (Ficus aurea and Ficus citrifolia). Winged adult beetles, 3.0–3.6 mm long, mate on Ficus twigs outside the syconia (fruits), and enter the syconia through holes cut by male pollinating wasps. Adults and larvae eat adult wasps within the syconia. Ovaries hold few, large, mature eggs. Larvae develop through three instars. Fully grown larvae abandon the syconia, drop to the ground, burrow to a depth of 1.5–3.7 cm, spin a silken cocoon, and pupate. Pupal duration is 8–9 days. Larval populations are highest in May, when penultimate stage syconia (phase D) are most abundant, but were detected in all months except June. Charoxus major is reported from Veracruz, associated with Ficus lapathifolia. Its adults extract wasp occupants of galled fig ovaries within syconia, and its eggs were found singly in empty galls.

Keywords:

• Charoxus
• Ficus
• Florida USA
• Veracruz Mexico
• tritrophic interaction

Acknowledgements

We thank Jorge Peña for allowing us to use his laboratory and microscopes, Robert Noonan for allowing us to use his photograph(s), Fred Bennett, Dale Habeck, Takuji Hayakawa, Tom Walker, and especially Julieta Brambila, Catharine Mannion and Linda Mason for collecting fig syconia in Broward, Collier, Dade, Hillsborough, Monroe and Palm Beach counties, and mailing them or delivering them to J.H.F. in 1988–92. We thank Carlos Artaud for identifying specimens of F. subcordata, Miguel Morón R. for providing laboratory facilities in Mexico, Araceli Aguilar M. for identifying specimens of Ficus lapathifolia, and Miguel García for allowing access to his F. lapathifolia tree at la Pitahaya, south of Xalapa, Veracruz. We thank Heather McAuslane and Paul Choate for critical manuscript reviews. We thank Lyle Buss for Automontage® photos of Charoxus adults, and Jane Medley for expert use of Photoshop® processing of them.