Hypothenemus hampei is a new invasive pest in China. It is a main coffee pest and poses a great threat to the coffee industry. The purpose of this study is to clarify the biological characteristics and field occurrence rules of the insect, and to provide a theoretical basis for later monitoring and forecasting and comprehensive management of the insect. In this study, the morphological characteristics, developmental duration and fecundity of various developmental stages of H. hampei were observed at each stage in the indoor feeding conditions. The annual life cycle of H. hampei was observed in the field. The population dynamics and spatial distribution patterns of H. hampei in Wanning city, Hainan province were measured through systematic field investigation from 2021 to 2022 to clarify the biological characteristics and field occurrence of H. hampei, and provide a theoretical basis for the subsequent integrated pest management of H. hampei. The results showed that the developmental duration of egg, larval, pupal and adult stage of H. hampei was (6.75±0.65) d, (17.41±1.63) d, (6.45±1.15) d, (42.74±9.55) d, respectively. The average generation duration was (73.35±11.26) d. The main morphological characteristics of each stage were as follows: egg, elliptic, milky white, with smooth and shiny surface; larval, usually “C” shaped, milky white, slightly transparent, with brown head and no feet; pupal, milky white at the initial stage, and later turn brown, the head hidden under the pronotum; adult body, cylindrical, dark brown to black, shiny; male smaller than the female. Female adults usually laid eggs under dark conditions, the number of eggs laid by a single female was 11.85±1.69, and the ratio of male to female was 10.25∶0.95. The results of indoor and field observations showed that H. hampei had seven generations a year in Hainan, and there was no phenomenon of overwintering. The results of the field survey in 2021—2022 showed that the population of H. hampei began to increase slowly from January, and the incidence of H. hampei increased sharply from April to May, reached a maximum of 60.15% and peak in May, and then declined rapidly. In October, it remained at a relatively stable level. The population increased again in November, with another small peak, reaching 19.87%. In December, it decreased, but it showed a slow increase until March of the following year related to the number of fruits. The survey results on space and orientation showed that during the fruit development period, H. hampei preferred the middle layer (0.5-1.0 m) fruit spatially, and preferred the east and north directions in orientation, which may be related to light and temperature. The results of the four aggregation parameters showed that H. hampei belonged to the aggregation distribution in both horizontal and vertical directions.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |