Phenology and laboratory rearing procedures of an Asian longicorn beetle, Glenea cantor (Coleoptera: Cerambycidae: Lamiinae)

Abstract

Glenea cantor (F.) (Coleoptera: Cerambycidae: Lamiinae) is an Asian longicorn beetle whose larvae bore under the bark of living trees of at least seven plant families and enter the wood for pupation. Here, we determined the phenology of this beetle on its natural host, kapok [Bombax ceiba L. = Gossampinus malabaricus (DC.) Merr], in an uncontrolled insectary at ambient environmental conditions, and we compared the efficiency of four larval rearing procedures at 25 ± 2°C, 75 ± 5% RH, and a photoperiod of 14:10 (L:D) h in the laboratory. It had five generations, including an overwintering generation, a year in southern China, with overlaps between generations and no diapause. Adults were present in early Marchearly December; eggs in early Aprilearly December; larvae almost year-round, and pupae in mid-Februarymid- April as well as mid-Maylate November. All larvae of the overwintering generation and the larvae of the fourth generation that hatched in and after mid-November overwintered. The longevity of females and males was 71.94 ±1.21 d and 46.87 ± 1.11 d, respectively, and mean fecundity was 106.65 ±3.61 eggs. Four larval rearing procedures using kapok twigs were tested: 1) 10 neonate larvae were left in the original host twig, 2) 10 neonate larvae were removed from the original bark and transferred to a new host twig, 3) 10 neonate larvae embedded in the original bark were transferred to a new host twig, and 4) a single neonate larva embedded in the original bark was transferred to a new host twig. We observed the survival of 300 neonate larvae for each rearing procedure. Approximately 81-85% of neonate larvae successfully developed to adult stage when neonate larvae were transferred together with the original bark to new host twigs; when neonate larvae were transferred without the original bark, only ≈38% of the inoculants became adults, and when larvae were left in original twigs, ≈52% of them reached adult stage. Resulting adults from different rearing methods and collected from the field had similar body weight and sex ratio. In terms of time, labor, and the number of resulting adults, procedure 3 is the most effective method for maintaining a laboratory colony. © 2011 Entomological Society of America.