筠连秦蛉(Chinius junlianensis leng,1987)的扫描电镜观察及其与白蛉亚科昆虫的演化关系

OBSERVATION OF CHINIUS JUNLIANENSIS LENG,1987(DIPTERA:PSYCHODIDAE) WITH SCANNING ELECTRON MICROSCOPY AND ITS RELATIONSHIP WITH EVOLUTION OF SUBFAMILY PHLEBOTOMINAE

目的 为了进一步研究筠连秦蛉与白蛉亚科昆虫的演化关系 ,对该蛉做扫描电镜观察 ,从形态结构上分析其与当代白蛉和化石蛉种的进化关系。 方法 常规扫描电镜标本处理 ,扫描电镜观察。 结果 雄蛉复眼由 13～ 16个小眼面组成 ,雌蛉由 16～ 2 1个小眼面组成 ,色素变浅 ;触角第 7节及以前节上的囊状刺为一光滑的刺 ,第 8节及以后节上的囊状刺呈三菱尖刺状 ,其根部有一卵圆形孔 ;感觉乳头为在卵圆形基部两侧伸出含 4～ 5根细刺的梳齿状的围栏 ,其中央有一根较粗的刺 ;下颚须上的牛氏器呈杵棒状 ;雄蛉腹部第 4、5节背板两前侧角与上一节交接处附近体表有许多呈蜂窝状小孔 ,此即筠连秦蛉雄蛉腹部的喇叭腺开口。 结论 筠连秦蛉退化的复眼、发达的感觉乳头、雄蛉腹部喇叭腺及宽圆翅等结构表明 ,它在进化上是源于古蛉属的一个现存最古老的小型洞栖“活化石”白蛉。

Objective To observe the ultrastructure of Chinius junlianensis with scanning electron microscopy(SEM) for studying the evolutionary relationship within phlebotomine sandflies. Methods Specimens of C. junlianensis were treated with SEM routine method,and examined by SEM. Results The compound eyes with light color pigment were composed of 13-16 ocelli in male and 16-21 ocelli in female. The antennal ascoids proximal to segment 7 were round spines in cross-section,and those distal to antennal 8 were roughly triangular,with three ridges and three concave surfaces,and had a large oval depression at their base. The antennal papilla was oval at base,with a comb-like fence of 4-5 thin pointed processes on each side and a stout central spine. The Newstead scales on palp liked sprouts. There were abdominal exosecreting organs with honeycomb-like openings at the inter-tergal junctions 3/4 and 4/5 of each side of male,these were the openings of trumpet gland of C. junlianensis . Conclusion Degenerated compound eyes,developed papilla,trumpet glands on tergite 4,5 of a male and wild round wings show that C. junlianensis is a small old ”living fossil” species which originates from Phlebotomides in evolution. (For Fig. 1-8,to see back cover)