File: <hydro1.ima.htm> [For educational purposes only] Terminology Glossary <Principal Natural
Enemy Groups > <Citations> |
Immature Stages
of Hydrophilidae
Detailed information on immature stages of Hydrophilidae is being
acquired. However, Clausen (1940)
noted that larvae of Hydrophilidae are voracious predators on a variety of
insects and other aquatic animals; while the adults are scavengers on
decaying plant and animal matter (Legner et al. 1980). Several species have been introduced for
biological control with no reported success. Aquatic hydrophilids are most often found in ponds, especially
those having extensive vegetative growth, although they also may be found
along streams. Adult beetles are
principally scavengers, consuming decaying animal matter and also living on
dead plant tissue. Many species feed
mostly on algae and other lower forms of plant life. Although most larvae are predaceous, there
are some exceptions. Predaceous forms
feed on various worms, snails, insect larvae and pupae, Entomostraca, small
fish, crayfish and tadpoles. They may
actually swallow bits of solid matter, but seem to prefer body fluids of
their prey. Oviposition behavior is distinctive because of the silken case
within which the eggs of many species are contained. Several more primitive subfamilies lay
their eggs singly, with little or no covering. In a few genera, the cases are attached to the body of the
parent by silken strands, while in others they are enclosed in a folded leaf,
placed on foliage underneath the water, or float free on the surface (Clausen
1940/62). The larvae of many aquatic
species are unable to swim, but rather move about by crawling along the
bottom or on vegetation, and may be found only partially submerged. Larvae of most species construct their
pupal cases out of the water, near the water line in mud, under various
objects, or on plants above ground. Enochrus is reported to form
its case from floating strands of Spirogyra. References: Please refer to <biology.ref.htm>,
[Additional references may be
found at: MELVYL Library ] |