Gené's organ which everts from the camerostome and coats the egg surface with waterproofing wax is indispensable for egg hatching. The ultrastructure of the tubular glands of Gené's organ in Haemaphysalis longicornis changes dramatically in accordance with stimuli of feeding and copulation. Cell proliferation followed by membrane supply due to fusing of small vesicles with the apical plasma membrane is induced by the onset of feeding. After the copulation, deep intercellular crypts with well-developed microvilli are formed and cell surface is conspicuously enlarged. The experiment using fed virgin females confirmed that these crypts cannot be formed without copulation. Simultaneously with crypt formation, abundant cytoplasmic inclusions are accumulated. In spite of secretion of abundant wax from the tubular glands, no exocytosis occurs during oviposition. This fact suggests that the low molecular compounds are released from the glandular cells by transmembrane transport.

View full abstract

Eurytetranychus koreanus sp. nov. is described from Hemiptelea davidii (Hance) Planchon in Chungju, Chungbuk, Korea. Measurements and illustrations of Tetranychina harti (Ewing), new to Korea, are also presented.

View full abstract

The drought tolerance of engorged I. persulcatus larvae was compared between the diapausing and non-diapausing groups. The survival rate abruptly decreased at74% RH and25°C in both engorged diapausing and engorged non-diapausing larvae. The mean longevity of the engorged diapausing larvae was significantly shorter than that of the engorged non-diapausing larvae when kept at74% RH and 25°C. The survival rate gradually decreased at 74% RH and 4°C in both larvae. There was not a significant difference in the mean longevity between the engorged diapausing and non-diapausing larvae when kept at 74% RH and4°C. These results suggest that engorged I. persulcatus larvae do not enhance the drought tolerance by the diapause.

View full abstract

Eleven cases of human tick bite in the Noto Peninsula, Ishikawa Prefecture, were noted during 1991 to 1994. Tick species involved were Ixodes nipponensis (6 cases), I. ovatus (4 cases), and Haemaphysalis flava (1case) . Four cases (36%) occurred during their daily activities. The inhabitants of this hilly peninsula are likely to be exposed to tick bite.

View full abstract