First report of Trypoxylon clavicerum (Crabronidae: Hymenoptera) from the Indian subcontinent: its nesting behaviour and prey preference

Abstract A study was conducted to document the nesting behaviour and prey composition of a crabronid wasp, Trypoxylon sp. The wasp was molecularly characterised as T. clavicerum (NCBI Accession No. OQ913679.1). Nest acceptance rate was significantly higher in the reeds of Ipomea carnea (79.20%) and bamboo (84.80%). The mean number of brood cells (4.40 ± 0.89 cells/nest) and vestibular cells (1.06 cells/nest) built by the wasp was significantly higher in the reeds of I. carnea . Brood parasitisation by the nest parasite Amobia sp. was significantly higher in nests built by the wasp in paper straws (58.57%) compared to the nests built in the reeds of bamboo (23.33%). The mean durations of the egg, larval and pupal stages of T. clavicerum were 2.60 ± 0.55, 6.01 ± 0.71 and 4.80 ± 0.84 days. The number of nests recovered was observed to be the highest during the months of August (3.66 ± 1.53 nests), September (5.00 ± 4.36 nests), October (8.67 ± 2.89 nests) and November (6.00 ± 2.10 nests). The major species of spider from the occupied nests belonged to two families, viz. Salticidae (81%) and Oxyopidae (19%). During the nesting period the adult wasp provisioned a greater number of spiderlings (3.25 to 3.60 spiderlings/cell) than adult spiders (1.20 to 1.60 adult spiders/cell) to her brood. The time taken to complete a single nest provisioned with adult spiders and spiderlings (13.20 ± 6.83 hr/single nest) was significantly less than for the nests provisioned with adult spiders (46.80 ± 14.80 hr/single nest) only. This study is the first ever report of nesting behaviour and prey composition of the spider-hunting wasp T. clavicerum from India.