File: <coleopt.htm> [For teaching purposes only; do not review, quote or
abstract] Terminology <Principal
Natural Enemy Groups>
COLEOPTERA
Please refer also to the following link for details on this group: Many families of
Coleoptera exhibit predaceous feeding behavior, and probably includes the
majority of all insect predators.
Species of Adephaga families Carabidae, Dytiscidae, Cicindelidae and
Gyrinidae are almost all predaceous.
They feed generally on insects of suitable size that occur in the
habitat, but they attack many other forms of small animal life as well. In Polyphaga, the principal predaceous
groups are Silphoidea (Silphidae), Staphylinoidea (Histeridae and
Staphylinidae), Cantharoidea (Cleridae, Lampyridae, Cantharidae),
Mordelloidea (Meloidae), and Cucujoidea (Coccinellidae). Even though most are general feeders,
certain families are very much restricted in host preference. Silphidae normally feed on larvae of Diptera
present in decaying animal flesh, while most Lampyridae, in both larval and adult
stages, feed mainly on snails, earthworms, etc. Most Meloidae are predaceous on eggs of Locustidae in the soil,
while several species develop in the cells of bees. The large family Coccinellidae, although having some
phytophagous species, attacks mainly Coccidae, Aleyrodidae and
Aphididae. In crop pest control, the
Carabidae and Coccinellidae are of especial importance (Clausen 1940/1962). A parasitic life
style is not so common in Coleoptera as it is in Hymenoptera and Diptera,
with ca. 8 families showing this behavior.
Most species of the small family Leptinidae exhibit a facultative
parasitism, and in the Staphylinidae many species of the Aleocharinae (Baryodma,
Coprochara and Aleochara) are parasitoids of Diptera
puparia. In Cleridae, several species
of Hydnocera are parasitoids, and some Trichodes seem to
develop in the same way. The
Ripiphoridae are entirely parasitic on hymenopterous larvae and
cockroaches. Some species of
Colydiidae (e.g., Deretaphrus and Bothrideres) are considered
parasitic, which is true also in Catogenus of the Passandridae. A few species of Anthribidae of the genus Brachytarsus
are considered parasitic inasmuch as the larval food is strictly limited to
the eggs beneath a single coccid host and the stimulus for oviposition is
provided by the scale host itself rather than by the eggs. A few Coccinellidae, only those which
attack the larger monophlebine Coccidae, may also be thought of as parasitic
because the larva may develop entirely at the expense of a single host
individual (Clausen 1940/1962). There are few
internal parasitoids among Coleoptera, except in the Ripiphoridae, where it
is normal for all species. Among
species attacking cockroaches the entire feeding period is passed internally,
while in those attacking larvae of Hymenoptera, the internal phase is
restricted to the latter portion of the 1st larval instar and the following
instars are external feeders.
Internal parasitism by Colydiidae is suspected, especially as isolated
records show larvae being collected from pupae of Chrysobothris. Parasitic
Coleoptera show a considerable uniformity in behavior and the manner of
development. In the families
Ripiphoridae, Staphylinidae and Meloidae, all species deposit their eggs apart
from the host stages on which development is to occur, placing them in the
soil, in host galleries, or on foliage or blossoms. First instar larvae of parasitic Staphylinidae search for
dipterous puparia in the soil of refuse habitat; those of Ripiphoridae
attacking cockroaches, and probably a few Meloidae attacking bees, gain
access to the host directly. The
majority of species of the latter two families that attack vespoid wasps and
bees, respectively, seem to require the services of a carrier to transport
them from the vicinity of hatching to the cell, and this role is usually
filled by the female wasp or bee (Clausen 1940/1962). Larval development among parasitic species
also reveals certain points in common that are not possessed by the
predaceous forms. A notable
hypermetamorphosis occurs during larval development. The planidium type of 1st instar larva is
of common occurrence in the Meloidae and Ripiphoridae and in parasitic
representatives of several other families.
Later larval instars assume a degenerate form in which the appendages
are much reduced and the powers of locomotion are very limited or entirely
lacking. Nonfeeding larval stages of
Meloidae have not been recognized in other parasitic groups of Coleoptera
with the exception of Drilidae (Clausen 1940/1962).
A early comprehensive review of the biology
and behavior of entomophagous Coleoptera were presented by Balduf
(1935). Böving & Craighead
(1930-1931) provided an illustrated synopsis of the larval forms of Coleoptera,
dealing especially with specialized larvae of a number of predatory and
parasitic species. References: Please refer
to <biology.ref.htm>, [Additional
references may be found at: MELVYL Library] |