光滑足距小蠹消化道的解剖结构

采用体视显微和扫描电镜技术研究光滑足距小蠹Xylosandrus germanus(Blandford)消化道的解剖结构。结果表明,光滑足距小蠹消化道由前肠、中肠和后肠三部分组成。成虫前胃由8个骨化的前胃板组成,呈灯笼状结构。前胃板由板状部和片状部组成,板状部短而简单,片状部甚长,由斜面、咀嚼刷和关闭刚毛组成。胃盲囊着生在中肠近后端,有细管状和囊状2种,成虫分别有1对,幼虫有1对细管状和3~5对囊状。6根马氏管分成2组,1组4根,另一组2根。6根马氏管与后肠肠壁形成隐肾系统。消化道具有1对囊状和1对细管状的胃盲囊可作为光滑足距小蠹成虫的识别特征。

Anatomical study of the alimentary canal of Xylosandrus germanus

The anatomy of the alimentary canal of Xylosandrus germanus （Blandford） was described with the aid of stereo and scanning electron microscope. The results showed that the alimentary canal of X. germanus was composed of foregut, midgut and hindgut. The adult＇ s proventriculus that composed of 8 proventricular plates was lanternshaped. Each plate was composed of anterior plate and posterior plate; the former was short and simple, while the later was long, and composed of declivity, masticatory brush and stopping bristles. The gastric caeca were located in the posterior region of midgut, being tube-shaped and sac-shaped. The adults had a pair of tube-shaped and a pair of sac-shaped gastric caecae, while the larvae had a pair of tube-shaped and three to five pairs of sac-shaped gastric caecae. There were six Malpighian tubules which were arranged in one group of four and another of two. The six Malpighian tubules and the hindgut wall constituted the cryptonephridial system. The adult could be identified by a pair of tube-shaped and a pair of sac-shaped gastric caecae in the alimentary canal.