Biology of Liriomyza

The genus Liriomyza. erected in 1894 (52), contains more than 300 species. They are distributed widely but are most commonly found in temperate areas; there are relatively few species in the tropics. Within this genus 23 species are economically important, causing damage to agricultural and ornamental plants by their leaf mining activity (94). Many of these damaging species are polyphagous, which is uncommon among the Agromyzidae; of 2450 de­ scribed species in this family only 11 are considered to be truly polyphagous, and 5 of these are in the genus Liriomyza (93). Serpentine leaf miner was proposed as a common name for any member of this genus because of the wide distribution, polyphagous nature, and morphological similarity of many of the species (98). The Entomological Society of America has adopted this naming policy, with a few exceptions (112). Indeed, many larvae of Liriomyza create serpentine mines, which are initially very narrow and gradually enlarge (57), often twisting through the leaf. However, the type of mine produced by Liriomyza may be influenced by the developmental stage of the leaf as well as by the host itself (99). Thus, the mines are not always serpentine in all host plants. In addition, mine location in leaves may vary considerably, and either the upper or lower leaf mesophyll may be mined (5, 71). Some species have larval stages that feed in potato tubers (50), bore through stems (34), and feed within seed heads (86). Most of our knowledge concerning the biology of this genus comes from studies on economically important species. These data have been developed largely since 1900, with an explosion of information since 1975 (76). This reflects the dramatic rise of Liriomyza spp. as major pests of numerous ornamental and agricultural crops over the past ten years (72). As a result of