Journal of the National Taiwan Museum

Abstract

Eocanthecona parva (Distant, 1902) (Hemiptera: Pentatomidae) is a common species of predatory stink bug in Taiwan. This study collected a fertilized female of E. parva in the field, which laid an egg mass (91 eggs) afterwards. After the eggs hatched, the nymphs were reared until they grew into adults. In the meantime we observed and recorded the development and morphological features of eggs and nymphs as well as what the nymphs fed on. It took a total of 36 days approximately for the eggs to hatch and develop into adults. The eggs hatched approximately 8 days after being laid, while the nymphal stage lasted for 28 days. The nymphs of various instars can be distinguished based on the following morphological features: (1) the first instar: the head bended downward, and the thorax was black; (2) the second instar: the thorax was black, and the lateral margins of the pronotum were wrnte; (3) the third instar: the thorax was black, and the lateral margins of the thorax and abdomen were white; (4) the fourth instar: the thorax was black, the lateral margins of the thorax and abdomen were white, and the wing-pads of the mesonotum developed to reach the posterior margin of the metanotum, while the wing-pads of the metanotum were undeveloped; (5) the fifth instar: the pronotum was red, the lateral margins of the abdomen were white, the wing-pads of the mesonotum developed to reach the third abdominal segment, and the wing-pads of the metanotum also developed. There were 83 hatchlings and 46 of them grew into adults. Except four adults that molted incompletely, there were 42 (19 females and 23 males) which eclosed successfully. The average body length of the females was greater than that of the males, and it took the former longer to develop into the adulthood than did the latter. The nymphs of E. parva fed on a number of crop pests of Lepidoptera provided. It's worth testing the potential of applying E. parva in the control of these pests in future studies.