PHOTOPERIODIC CONTROL OF DIAPAUSE IN 5 SPECIES OF COCCYGOMIMUS (HYMENOPTERA, ICHNEUMONIDAE) FROM HOKKAIDO, JAPAN

The effects of photoperiod and temperature on development and diapause in five species of Coccygomimus: C. pluto Ashmead, C. instigator Fabr icius, C. alboannulatus Uchida, C. aquilonius japonicus Momoi, and C. disparis Viereck from Hokkaido, Japan were investigated. Based on :he patterns of photoperiodic control of diapause, these species were clas sified into two groups. In C. pluto and C. instigator, 90%-100% of ind ividuals entered deep diapause in the final larval instar at 12L-12D a nd 13L-11D at 20 degrees C; the incidence of diapause was lower at sho rter or longer photoperiods. In C. aquilonius japonicus and C. alboann ulatus, the incidence of diapause was high at 13L-11D at 17 and 20 deg rees C. These four species can be grouped together. In C. disparis, di apause occurred at short photoperiods at 15, but not at 17 and 20 degr ees C and development was slightly retarded during the prepupal stage at short photoperiods. This species can be classified separately from the other four species. These five Coccygomimus species were sensitive to photoperiod only immediately before the diapause stage. Diapause e nded at transfer from a short to a long photoperiod. A shift in temper ature from 20 to 25 degrees C did not terminate diapause except in C. disparis where a shift from 15 to 20 or 25 degrees C stimulated resump tion of rapid development. Based on these and other results, it is lik ely that photoperiodic control of diapause in Coccygomimus species is constrained by phyletic relationships, rather than by geographic distr ibution.