An important aspect of the association of Lype phaeopa (Stephens) with submerged wood is the oviposition behavior of adult females, which preferably oviposit their eggs on moist emergent or submerged parts of woody debris with a structured surface. The eggs are commonly deposited in cracks and crevices using the elongated ovipositor. Ovipositor morphology and various sensilla on the tip and along the ovipositor were studied by scanning electron microscopy and their possible function discussed. Structure of these sensilla and pre-oviposition behavior of the females point to a preference for certain oviposition sites on woody debris. This may be a key factor for the distribution and development of the larvae.