Abstract: 【Aims】 To clarify the morphological and biological characteristics of the tea weevil, Myllocerinus aurolineatus, so as to provide a scientific basis for the accurate identification and the development of green control technologies for this insect pest.【Methods】 M. aurolineatus larvae and adults were reared with field-collected soils and fresh tea branches, respectively, in the laboratory under (25±1) ℃. The main morphological characteristics of M. aurolineatus at various developmental stages were observed under light microscope. Field investigations were conducted to learn the migratory behavior of M. aurolineatus larvae in different soil layers of tea plantation, and the distribution pattern in soil upon pupation. The calling, mating and phototactic behaviors of M. aurolineatus adults were recorded and described with a combination of laboratory observation and behavior test.【Results】The freshly laid eggs of M. aurolineatus are creamy white and gradually turn light yellow. The fleshy larvae have no legs and are usually curved or shaped like the letter C. The naked pupa is milky white with an obvious mouthpart and a pair of wing buds. The mature adults are grayish-black and possess yellowish-green shiny scales and stripes on the sheath wings. And the body size of females is always slightly larger than that of males. M. aurolineatus overwinters in the larval stage in the soil layer of 20-30 cm in depth from the ground and its pupation peak occurs in mid-late April. For pupation, the mature larvae will migrate to the soil layer of 0-10 cm in depth from the ground, and the larvae and pupae in the soil layer of 0-5 cm in depth from the ground accounted for 75.83% of the population. M. aurolineatus adults usually mate from 16:00 to 4:00, and copulate in a “false male-above” position, in which the male sits on top of the female. The whole mating period lasts for 44-132 min, and the mating procedure consists of four stages including pre-copulation, copulation, insemination and post-copulatory mate guarding. In addition, both female and male adults of M. aurolineatus are strongly phototactic in the evening. 【Conclusion】In the present study, the main morphological characteristics of M. aurolineatus at various developmental stages have been clarified, and the vertical migrating behaviors of larvae in the soil of the tea plantation and the vertical distribution patterns in different soil layers during the peak period of pupation have been examined. In addition, the mating and phototactic behaviors of the adults have been preliminarily revealed. The results not only provide references for the accurate identification of M. aurolineatus, but also can give theoretical supports for the development of green control technologies.

Key words: Myllocerinus aurolineatus, morphology, biology, vertical distribution, calling and mating behaviors, phototaxis