<i>Microlarinus lypriformis</i> and <i>Microlarinus lareynii</i> (Coleoptera: Curculionidae): biology and use with IPM strategies to control puncturevine

Abstract Puncturevine, Tribulus terrestris L. (Zygophyllaceae) is a summer annual plant, native to Asia, southern Europe, and northern Africa. It is an invasive and troublesome weed that injures livestock, lowers forage quality, and punctures bicycle tires among other things. Microlarinus lypriformis (Wollaston) and Microlarinus lypriformis (Jacquilin de Valand) (Coleoptera: Curculionidae) are 2 species of biological control agents that were imported to the United States in the early 1960s to control puncturevine. Despite the potentially high reproductive rate of Microlarinus weevils and their ability to induce mortality of puncturevine plants, the weevils have had mixed success in reducing puncturevine populations. Potential causes of the variable success include mismatches in the climatic ranges and biology of the host plant and insect. Integrated weed management strategies have the potential to improve the impact of Microlarinus weevils on puncturevine, but thus far have been understudied and underutilized. A review of insect biology, description of life stages, host plant, biological control use, and contribution to integrated pest management is presented.