title: Effects of environmental factors and appendage injury on the wing variation in the cricket Velarifictorus ornatus.
abstract: The effects of environmental factors and appendage injury on the wing variation in Velarifictorus ornatus (Shiraki) (Orthoptera: Gryllidae) were investigated. The percentage of micropters was more than 95% when the nymphs were reared at constant photoperiods, and changing photoperiod did not affect wing variation in V. ornatus at 25 or 30°C. In the crowding experiment, the percentage of macropters was only 11.2% when the nymphs were reared separately at 25°C. In contrast, the percentage of macropters was significantly higher when the rearing density was increased to two nymphs per container and lower when the rearing density was increased to five or 10 nymphs per container. These results indicate that low and high rearing densities induce micropters, but intermediate rearing density stimulates the formation of macropters. Meanwhile, severance of appendages, such as antennae, femora, and tibiae, in the nymph stage exerted a micropterizing effect. The period sensitive to such stresses ranged from 35 to 60 days of nymph development.
authors.affiliation: Laboratory of Insect Behavior & Evolutionary Ecology, Central South University of Forestry and Technology, Changsha, Hunan 410004, China zhaolvquan80@163.com.
authors.forename: Lü-Quan
authors.initials: LQ
authors.lastname: Zhao
authors.affiliation: Laboratory of Insect Behavior & Evolutionary Ecology, Central South University of Forestry and Technology, Changsha, Hunan 410004, China Laboratory of Zoology, Hunan First Normal University, Changsha, Hunan 410205, China daohongzhu@yeah.net.
authors.forename: Dao-Hong
authors.initials: DH
authors.lastname: Zhu
mesh_terms: D000818:Animals; D004777:Environment; D006135:Gryllidae / Q000033:anatomy & histology*; D009758:Nymph; D017440:Photoperiod; D011156:Population Density; D014921:Wings, Animal / Q000033:anatomy & histology* / Q000293:injuries
keywords: Gryllidae; density; injury; photoperiod; wing dimorphism