柑桔爆皮虫幼期各虫态的形态学观察

采用田间观察和室内观察相结合的方法，使用Leica MZ 16A研究型体视解剖镜，对柑桔爆皮虫Agrilus auriventris Saunders幼期各虫态的形态进行了系统的观察。结果发现：卵初产时为乳白色，后变为浅褐色并开始皱缩，末期变为黄褐色，孵化前部分卵壳分离为白色蜡质外层和黄褐色内层两层；幼虫孵化的同时直接从卵壳贴近树皮的一侧蛀入韧皮部，同时将大量虫粪排入卵壳；幼虫随着虫龄的增加钳状突的阶数和口上片的宽度发生有规律的变化，末龄幼虫在木质部作一椭圆形蛹室化蛹，身体的头部和尾部以3∶7的比例对折； 化蛹前的幼虫经历一个身体缩短的预蛹状态；刚化的蛹为乳白色，复眼颜色与身体相似，化蛹后蛹的颜色逐渐变为淡黄色，复眼颜色变为浅红褐色，后期复眼变为红褐色，口器变黑，羽化前蛹的复眼、口器和体表全部变黑；羽化过程中，成虫体表的膨胀导致蛹表皮脱裂，前翅变黑和腹部背面变成碧蓝色后羽化成完整的成虫。本结果进一步支持将柑桔爆皮虫幼虫期分为5龄。

Morphological observation on the immature stages of Agrilus auriventris Saunders (Coleoptera: Buprestidae)

Morphology of immature stages of the citrus borer (Agrilus auriventris Saunders) was studied in details both in field and in the laboratory using Leica MZ 16A stereo microscope with Leica IM 1000 system. The results showed that eggs were creamy white when first laid, but they became yellow and wizened with age. Before hatching, white and waxen outer layer and yellow inner layer were derived from the chorion; during hatching, the larva bored directly into phloem from the bottom part of the egg adhered to the bark with sawdust-like dejecta in the chorion. The shape of larval urogomphi and the width of peristoma varied with increase of instar, and the last-instar larva made a elliptic cell in the xylem with its body folded from head to tail with a ratio of 3∶7. A prepupal stage appeared before pupation; when the pupae aged, their body turned yellow and compound eyes became rufous from creamy white, and then, a status with yellow body, rufous compound eyes and black mouthpart appeared. Before eclosion, the whole pupa became black; during eclosion, exuvia cracked as the expand the adult body. After the fore wings became black and the dorsal aspect of the abdomen blue, the adult gained all adult characters. This study further confirmed that the larvae of this beetle had 5 instars.