Fine structure of the eggs of Haemagogus equinus and Hg. janthinomys (Diptera: Culicidae)

The eggs of Haemagogus equinus Theobald and Hg. janthinomys Dyar, the first of this genus to be examined with a scanning electron microscope, are described from material collected in Trinidad, West Indies. All surfaces of the eggs are described, including both dorsal and ventral surfaces at the anterior and posterior ends as well as the micropyle and associated apparatus. The dorsal surface, normally attached to the substrate, consists of a dense, hairlike mat of filaments formed from numerous, greatly elongated outer chorionic tubercles. These filaments possibly serve to improve anchorage of the egg as a protection against flushing by rain water or physical removal by predators. The outer chorionic cells on the ventral (upper) surfaces are extremely similar to those of two species of the subgenus Finlaya of Aedes, Ae. albolateralis (Theobald) and Ae. melanopterus (Giles), both collected in Taiwan.