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COLEOPTERA, Misc. Families of Coleoptera -- [Latest Classification] Please refer also to the following link for further details: Photos-1, Photos-2 Description & Behavior Principal Families References Clausen (1940) reported on several families of
Coleoptera that are associated in varying capacities with ants, some are
definitely known to be predaceous on the ant broods, and others that are
principally scavengers. These were
Clavigeridae, Brentidae, Pselaphidae, Leptinidae and Paussidae. Park (1929) considered that Leptinus
testaceus Muell., and possibly the entire Leptinidae, exhibit a
facultative parasitism. Some
Brentidae and Cryptophagidae are found in bark and wood under conditions that
indicate they might be predaceous on other insects occupying the same
habitat. 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. The word Coleoptera
comes from the Greek koleos, meaning "sheath"; and pteron, "wing", hence "sheathed
wing." The order has more
described species (ca. 400,055) than any other order of animals: this amounts to about 42 percent of all
described insect species. These
figures change as specialists become aware of the vast number of yet
undescribed species. The largest taxonomic family, the Curculionidae
(weevils) are Coleoptera. Only the
Hymenoptera (bees, wasps) may have as many or more species. Beetles occur in most habitats, but are not
known from oceans or polar regions. They generally feed on plants and fungi,
but also attack other invertebrates. Some species serve as prey of other
animals, e.g., birds and mammals. Many species are pests of agricultural
crops (e.g., Colorado potato beetle Leptinotarsa decemlineata, boll
weevil Anthonomus grandis, red flour beetle Tribolium castaneum,
and the cowpea beetle Callosobruchus maculatus). Others act as
biological controls of some agricultural pests; e.g., Coccinellidae
(ladybugs) are predators of aphids, scale insects, thrips, and other
plant-feeding insects. The beetles have a
holometabolous life cycle; a prothorax that is distinct from and freely
articulating with the mesothorax; the meso- and meta-thoracic segments fuse
to form a pterothorax; there is a depressed body shape with the legs occur on
the ventral surface; the coxae of the legs are recessed into cavities formed
by sclerotised thoracic sclerites; the abdominal sternites are more
sclerotised than the tergites; the antennae have 11 or fewer segments; and
terminal genitalic appendages are pulled into the abdomen and not apparent
when at rest. The anatomy is uniform,
variations in appearance and function among the families. An especially hard exoskeleton and hard forewings, or elytra,
are present. The exoskeleton is made
up of plates or sclerites, which are separated by sutures. This construction
produces armored defences for the beetles while still maintaining flexibility.
The elytra are not used for flying, but cover the posterior part of the body
and protect the second pair of wings.
They have to be raised hind wings to initiate flight. The flight wings
have crossed veins and are folded after landing, often along these veins. Some species do not fly
at all, including some ground beetles (Carabidae) and some true weevils
(Curculionidae). There are also some desert and cave-inhabiting species that
are flightless. Many of these have fused elytra, which form a shield over the
abdomen. In some families, both flying and the elytra have been lost, e.g.,
glow-worms (Phengodidae). The mouthparts are like
those of grasshoppers. The mandibles are large pincers that emanate from the
head some beetles. They appear as pair of hard, frequently tooth-like
structures that move horizontally to hold food or to serve as defence. Two
pairs of finger-like appendages occur around the mouth in most beetles, which
enable food to move into the mouth. These are formed from the maxillary and
labial palpi. The compound eyes may have great adaptability, as in
Gyrinidae where the eyes are split to enable the insect to see both above and
below water surfaces. Other species also have divided eyes, e.g., longhorn
beetles (Cerambycidae) and weevils.
There are also beetles that have notched eyes, and a few genera also
have ocelli that are located back on
the head. The antennae are mainly
organs of smell, but they may serve
to test the physical environment. They are also important during mating or
defence in some groups. Antennae vary, but are usually similar within any
given family. Sometimes the males and females of a species have different
antennal forms. Antennae may be clavate serrate, pectinate, filiform, geniculate,
moniliform. The legs have several
segments ending in 2-5 smaller segments or tarsi. Claws usually are present
on each leg. The legs legs are used mainly for walking, but they may serve
for other uses as well. In the aquatic families Dytiscidae, Haliplidae and
Hydrophilidae, etc., the legs may be modified for swimming and often bear
rows of long hairs. Other beetles have fossorial legs that are widened and
spined for digging. These adaptations
are found among the scarabs, ground beetles, and clown beetles (Histeridae).
The hind legs of some beetles, such as flea beetles (Chrysomelidae) and flea
weevils (Curculionidae), are enlarged and serve for jumping. One female may lay from
several dozen to thousands of eggs during her lifetime. The eggs are usually
laid in places where the larva will feed on hatching. The larvae are
generally the feeding stage of the beetle life cycle. They tend to feed
immediately upon emerging from their eggs. Some feed externally on plants,
while others feed within their food sources. Many Buprestidae and longhorn
beetles are external feeders. The larvae of other families are predacious
like the adults (ground beetles, ladybirds, rove beetles). Although the
larval period varies it can extend into several years. Beetle larvae are quite
distinct from other insect larvae because of their hardened, often darkened
head, their chewing mouthparts, and spiracles along the sides of the body.
They vary in appearance, especially between the families. Ground beetle
larvae are flattened and very mobile, while some rove beetles have larvae
that are campodeiform.
Elateriform larvae (Elateridae &
Tenebrionidae) appear as hardened worms with dark head capsules and tiny
inconspicuous legs. Scarab beetles (Scarabaeidae) have short, thick larvae
that are called grubs. All beetle
larvae go through several instars.
Some beetle groups, especially those with parasitic habits, have a planidium,
which is highly mobile, eg., Meloidae and some rove beetles in the genus Aleochara. Mating may involve
intricate behavior. In burying
beetles (Nicrophorus) combat may occur between males & females
continue until only one of sex remains. Some males are territorial and will
fiercely defend their territory from other males. These males may have horns
on their head or thorax, to enhance their overall body size. Pairing is usually short but in some cases
will last for several hours. Parental care varies
among the species, ranging from simply laying eggs under a leaf to certain scarab beetles, which make
underground structures complete with a supply of dung for their young. Other
beetles are leaf rollers, that laying their eggs in the curled plant
material. Protection from predators
includes mimicry, camouflage,
toxicity, and active combat.
Camouflage includes the use of coloration or shape to blend into the
surroundings. This kind of protective coloration is common and widespread
among beetle families, particularly those that feed on wood or vegetation,
e.g., Chrysomelidae. In some of these species, sculpturing or colored scales or hairs change the
beetle's appearance to resemble bird dung or other inedible objects. Mimicry is another
defence that often uses color or shape to ward off predators. A number of
longhorn beetles (Cerambycidae) strongly resemble wasps, which helps them
avoid predation even though the beetles may be harmless. This kind of defence
also can be found in scarab beetles. Beetles may combine their color mimicry
with behavioral mimicry, acting like the wasps they resemble. Species such
as ladybirds, blister beetles, and
lycid beetles may secrete toxic substances that make them unpalatable or poisonous. Large ground beetles and longhorn beetles may ward off
predators with strong mandibles and/or spines or horns to forcibly cause a predator to stay away. Others, such as
bombardier beetles (Carabidae), may spray liquids from their abdomen to repel
predators. Food habits vary among
the species. Some are omnivores, eating both plants and animals. Others are
specialised in their diet. Many leaf beetles, longhorn beetles, and weevils
are host specific, feeding on only a single plant species. Ground beetles and
rove beetles (Staphylinidae, etc.) are carnivorous and will catch and consume
many other arthropods and small prey such as snails and earthworms. A few
species have specific prey preferences.
Decaying organic matter is a principal diet for many species. This can
range from dung, which is consumed by coprophagous species (Scarabaeidae), to
dead animals, which are eaten by necrophagous species (Silphidae). Some
beetles that occur within dung and carrion are predatory, such as the clown
beetles, preying on the larvae of coprophagous and necrophagous insects. Adaptations
to the environment vary greatly within the order. Aquatic
beetles have several ways of retaining air beneath a water's surface. Beetles
of the family Dytiscidae hold air between the abdomen and the elytra.
Hydrophilidae have hairs on their under surface that retain a layer of air.
Adult crawling water beetles use both their elytra and their hind coxae for
air retention, while whirligig beetles carry a
bubble of air when diving.. Many household, agricultural
and forestry insect pests occur among the beetles. Of particular importance
are the following: The Colorado potato
beetle, Leptinotarsa decemlineata, is a serious pest of potato plants.
Crops may be devastated and only treatments of pesticides will mitigate
damage. Flour beetles are pests
of stored cereal crops. They feed on wheat and other grains and are adapted
to dry environments. They are serious pests of agriculture and have become
highly resistant to insecticides. The boll weevil, Anthonomus
grandis, has done billions of dollars in damage since it first entered
North America. The bark beetles Hylurgopinus
rufipes and Scolytus multistriatus, the elm leaf beetle, Pyrrhalta
luteola, and other beetles attack elm trees. The bark beetles are
important elm pests because they carry plant pathogens. The spread of certain
fungus by the beetle has destroyed elm over a wide range of North America. The death watch beetle, Xestobium
rufovillosum, (Anobiidae) is a serious pest of older wooden buildings in
Europe. It attacks hardwoods such as oak and chestnut, always in association
with fungi. The mountain pine beetle
attacks mature or weakened lodgepole pine in North America, where it destroys
vast stands of timber. Some beetles are
beneficial to humans, through their regulation of pest insect
populations. Both the larvae and
adults of some ladybugs (Coccinellidae) are predators of aphid. Other
ladybugs feed on scale insects. Ground beetles
(Carabidae) are predators of many insects and other arthropods, including
wireworms, fly eggs and caterpillars.. Plant-feeding beetles
may also be beneficial in the control problem weeds. Some flea beetles of the
genus Aphthona feed on Euphorbia esula (leafy spurge,
Euphorbiaceae), a weed of rangeland in western North America. Dung beetles (Scarabidae) have been used to reduce the
populations of pestilent flies and parasitic worms that breed in cattle dung.
The beetles reduce the availability of dung to breeding pests by rolling and
burying it in soil. This also
improves soil fertility and nutrient cycling. = = = = = = = = = = = = = = = = References: Please refer to <biology.ref.htm>, [Additional references
may be found at: MELVYL
Library] Arnett, R. H., Jr. & M. C. Thomas (2001). "Haliplidae". American
Beetles, Volume 1. CRC Press, Boca Raton, Florida. pp. 138–143. Arthur V. Evans,
A. V., Charles Bellamy, and Lisa Charles Watson, An Inordinate Fondness
for Beetles ISBN 0-520-22323-3 Beckmann, P. Living Jewels: The Natural Design of
Beetles ISBN 3-7913-2528-0 Besuchet, C. 1956.
Biologie, morphologie et systématique des Rhipidius (Col.
Rhipiphoridae). Mitt. schweiz. Ent.
Ges. 29: 73-144. Béthoux, O. (2009). "The earliest beetle
identified". = 83 (6): 931–937. Chapman, A. D.
(2009) (PDF). Numbers of Living Species in Australia and the World
(2nd ed.). Department of the Environment, Water, Heritage and the Arts.. Cooter, J.
& Barclay M.V.L. (eds.) (2006) A Coleopterist’s Handbook. Amateur
Entomological Society. 439 pages. ISBN 0-900054-70-0 Entomological
Society of America, Beetle Larvae of the World ISBN 0-643-05506-1 Grimaldi,
D., Michael S. Engel, Evolution of the Insects ISBN 0-521-82149-5 Hammond, P.,
M. 1992. Species inventory. pp. 17–39 in Global Biodiversity, Status of the
Earth’s Living Resources, B. Groombridge, ed. Chapman and Hall, London. 585
pp. Harde, K.
W. A Field Guide in Colour to
Beetles ISBN 0-7064-1937-5 Pages 7–24 Khnzorian, S. M. 1957.
A new representative of Rhipidius from Armenian SSR (Coleoptera,
Rhipiphoridae). Dok. Akad. Nauk
Armiansk. SSR. 24: 231-32. Liebher, J.
K. and Joseph V. McHugh in Resh, V. H. & R. T. Cardé (Editors)
2003. Encyclopedia of Insects. Academic Press. Mosher, D.
(December 26, 2007). "Modern beetles predate dinosaurs".
Live Science.. Remo, A. R.
(September 27, 2007). "Beetles infest coconuts in Manila, 26
provinces". Philippine Daily Inquirer. Riek, E. F. 1955. The Australian Rhipidiine Parasites of Cockroaches
(Coleoptera: Rhipiphoridae). Austr. J. Zool.
3: 71-94. Ross H.
Arnett, Jr. and Michael C. Thomas, American Beetles (CRC Press,
2001–2002). ISBN 0-8493-1925-0 Selander, R.
B. 1957. The systematic position of the genus Nephrites and the phylogenetic relationships
of the higher groups of Ripiphoridae (Coleoptera). Ann. Ent. Soc. Amer.
50: 88-103. The Mountain Pine Beetle in British Columbia. Natural
Resources Canada. August 19, 2008. Retrieved June 24, 2010. White, R.E.
1983. Beetles. Houghton Mifflin Company, New York, NY. ISBN 0-395-91089-7 |