Sensory organs of adult Amphilina foliacea (Amphilinida).

The distribution and morphological diversity of the sensory structures on the body surface, proboscis and caudal cavity of adult Amphilina foliacea have been investigated. Fifteen different types of receptors are described. Along with nonciliated and uniciated receptors bi- and multiciliated receptors have been found for the first time. The zonal distribution of the sensory structures and their coincidence within the same areas of the body surface have been revealed. The concentration of sensory structures at the posterior end may indirectly confirm a hypothesis of the unavailability of developed attachment disk in ancestors of amphilinids.