榆树金花虫啮小蜂Tetrastichus sp.,是酿成全省性灾害的榆树金花虫Pyrrhaltaaenescens Fairmaire的一种卵寄生蜂。此蜂81年7月在南阳县高庙公社孙楼村采回的金花虫卵中首次发现;我们在三年中对该蜂的主要形态特征、习性、分布和寄生情况进行了观察研究,现整理如下: 一、成虫形态特征 Ulmus Tetrastichus sp. Is an egg parasitic wasp that causes Pyrrhalidaenescens Fairmaire, an elm tree flower that causes a province-wide disaster. The bee was firstly found in the gold flower eggs recovered from Sunlou Village, Gaomiao commune, Nanyang County, in July of this year. We observed and observed the main morphological characteristics, habits, distribution and parasitism of the bee in three years. Now collated as follows: First, adult morphological characteristics