抄録
The distribution of larvae of Hirosia iyoensis was surveyed at the forest floor along a small branch of the Oyabe River of Toyama Prefecture. A total of 129H. iyoensis larvae was collected from leaf litter and soil at six different stations within 200m of the blood-sucking sites (a wide space opened at the main course of the Oyabe River) for H. iyoensis. Most of the larvae were collected within an 80m area of the blood-sucking sites. A total of 102 larvae was also collected at four stations with different altitudes (5,25,50 and 75m above the surface of the stream). The number of larvae collected tend to decrease in accordance with the elevation. This survey suggested that the breeding-places of larvae of H. iyoensis were the forest floor near the bloodsucking site of adults.
