The effects of photoperiod on pre-imaginal development and reproductive maturation of adult females of the multicolored Asian lady beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), were investigated at 20°C and at photoperiods from 10L : 14D to 18L : 6D. Experiments were conducted on a laboratory strain that originated from the Russian Far East. Larvae and adults were fed on the green peach aphid Myzus persicae. Under short day conditions the pre-imaginal development was faster than under long day conditions. The acceleration of pre-imaginal development occurred when day length was shorter than 16 h and the threshold day length was ca 14 h. The rate of reproductive maturation of adult females, in contrast, was twice as high under long day conditions, with the threshold between 14L : 10D and 12L : 12D, although even under short day conditions ca 10% of the females show a tendency to mature more quickly. This difference between the thresholds of these two photoperiodic reactions indicates they are relatively independent of one another. and Sergey Ya. Reznik, Nina P. Vaghina.
The seasonal changes of the nematode Camallanus anabantis Pearse, 1933, in the climbing perch (Anabas testudineus) from the freshwater swamps near Kalyani town, West Bengal, India were studied during the period from February 1988 to August 1989. The nematode exhibited a one-year cycle. Larvated females occurred in the fishes from October to February at a water temperature of 12“-29 °C. New infection of fishes occurred from February to May and occasionally in September. The fourth-stage larvae, the males, and the young females (without eggs), although irregularly, were found present throughout the year. Egg-laden females occurred in the fishes in August, October to February, and March.