NESTING-BEHAVIOR OF KROMBEINICTUS-NORDENAE LECLERCQ, A SPHECID WASP WITH VEGETARIAN LARVAE (HYMENOPTERA, SPHECIDAE, CRABRONINAE)

Nesting behavior of the recently described Sri Lankan wasp, Krombeinic tus nordenae Leclercq, is discussed. Females nest in the hollow intern odes of the leguminous myrmecophyte, Humboldtia laurifolia Vahl. The b iology of this stem-nesting crabronine is unique among Sphecidae in se veral aspects. An adult female exhibits remarkable maternal care, rear ing one larva at a time, and feeding it progressively. Progressive pro visioning has not been noted previously for any Crabroninae. Nests lac k cell partitions and mature larvae are transported to the basal regio ns of their stems for cocoon spinning. The cocoon is also unlike that of any other known crabronine species, exhibiting adaptations to inter node morphology and allowing movement of adults within the nest cavity . Finally, K. nordenae is remarkably different from all other known Sp hecidae in feeding pollen rather than paralyzed arthropod prey to its larvae.