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The sucking snout and the narrow shape of the "inverted South American" plates above the eyes point to this common species, although the identification is not certain. The very common species H. globosa, has scales that are wider and almost touch each other between the eyes (Besseling, 1964). In this photo, it is not visible that the eyes are double, mites have four eyes and in Hydrachna these are placed in two groups. The addition globosa is not specific, because many Hydrachnids are convex. All have a rostrum, the sucking snout that is also visible here. The sharp chelicerae are stored in this snout and together they form a specialized organ for sucking insect eggs, especially those of water boatmen (Davids, 1979)..
Not only the eggs of the water boatman, but also the adults are plagued by Hydrachna species: they are the victims of the larvae . These swarm, as soon as they have hatched, through the water and attach themselves with their relatively large jaws to the legs or the body of the bugs. They remain there to suck the body fluids of the insect, until they reach the next stage of their development. The larvae of the H. conjecta species attach themselves to the underside of the elytra (Davids, 1979).
Below is a darker and smaller specimen, found a month earlier, on 7 June 2010, in a communicating ditch. This was a water mite in the nymph stage, because there were no developed genitalia yet. The broader scales above the eyes point to H. globosa, but nymphs cannot be determined on the scales and it could also be a nymph of H. conjecta. Click on the picture for more.
