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Lu . diabol ica . This is consistent with the paucity of adult 

 collection records from July to August. It should be noted that 

 Lindquist (1936) collected the species during July, 1934, near Sonora, 

 Texas, indicating that a summer diapause is not universal throughout 

 the species' geographic range. 



Ready and Croset (1980) showed that for two Mediterranean sand 

 fly species, P. ariasi Newstead and _P. perniciosus Tonnoir, 

 environmental stimuli (photoperiod and temperature) can induce a 

 growth arrest, even in midsummer, that is not immediately reversible, 

 i.e., a true diapause. 



Late-instar _Lu. diabol ica developing in the outdoor colony 

 probably entered a true winter diapause (hibernation), but since they 

 were unnaturally exposed in rearing vials, and could not protect 

 themselves against the cold, they succumbed to subfreezing 

 temperatures. It is the author's opinion that some would have 

 survived the coldest winter days (-9°C) had they been afforded the 

 opportunity to secrete themselves under a blanket of leaf litter or in 

 a crack in the soil. Soil temperatures (10 cm depth) did not drop 

 below 8°C at any time during the winters of 1982 or 1983 (Agronomy 

 Dept. and NOAA cooperating, Gainesville, FL, 1982, 1983). 



Since the outside colony and field populations were located 

 virtually at the same latitudes and experienced similar photoperiods 

 and seasonal temperatures, it is likely that the same patterns of 

 diapause occur in the field. Lu_. diabol ica probably produce two to 

 four generations per year. In a two generation (bi vol tine) strategy, 

 the lst-generation adults emerge in late May and early June and 

 deposit fast-developing eggs, which hatch in 8 to 10 days to produce 



