Color changes in Halyomorpha brevis (Heteroptera: Pentatomidae) correlated with distribution of pteridines: regulation by environmental and physiological factors.

Halyomorpha brevis (Heteroptera: Pentatomidae) produces adults with different color patterns, most noticeable in the sternum. The color, ranging from ivory to red, depends on the extent of the accumulation of red pigment. The present work investigated the effects of photoperiod, temperature and aging on the pigmentation. The red pigment was identified as erythropterin by comparing the Rf with standard pteridines in paper chromatography in three solvent systems. Erythropterin was found in all organs, red or light red. Uric acid was detected prominently in ivory or light red sternum. A negative correlation was found between the extent of red pigmentation and that of uric acid content. The relative proportion of males and females with a red sternum progressively increased as they aged from day 0 to day 20 after adult emergence, particularly in males reared under a long day (non-diapausing). In males, an age-dependent decrease in red pigmentation was observed in the gastric ceca and tracheae. The sternum was lighter in short-day adults (diapausing) than that in non-diapausing adults at the same age, and the latter never achieved the intense red color. The possible functions of pteridines are discussed.