Saw-toothed grain beetle
Encyclopedia
The sawtoothed grain beetle, Oryzaephilus surinamensis, is a slender, dark brown beetle
2.4–3 mm in size, with characteristic "teeth" running down the side of the prothorax
. The sawtoothed grain beetle is a primary pest, in the UK, that attacks damaged grain. Carolus Linnaeus
, the Swedish naturalist who defined taxonomic arrangements for the animal, plant, and mineral kingdoms acquired samples of the sawtoothed grain beetle from Suriname
(Dutch Guiana) and named the species
"Oryzaephilus surinamensis" because of this. (It is Latin
for "rice-lover from Surinam".)
A relative of the sawtoothed grain beetle of the same genus
, the merchant grain beetle
, is more likely to be found in domestic dwellings since it requires higher more stable temperatures and can be found infesting biscuits and fruit and nut products. The adults can fly but rarely do. They can be differentiated by looking at the distance of the eye to the prothorax: with the merchant grain beetle it is less than half the vertical diameter of the eye.
The sawtoothed grain beetle lays its eggs loosely on foodstuffs at the rate of 6–10 per day, with total being 370 per female. The larva
e are to be found within the mass of the foodstuff in the top centimetre or two. As mentioned above damaged cereal is entered through broken kernels, and the larvae feed on the germ
, causing damage by reducing the percentage of grains which will germinate.
The total life cycle is 20–80 days at 18–37 °C (64.4–98.6 F).
The sawtoothed grain beetle can survive in unheated warehouses in the UK, and is considered the most important pest of home grown grain in the UK. The beetles survive the winter hiding in cracks and infest new stocks of grain the following year. Both insects are distributed throughout the world and regularly imported into the UK in unprocessed cereals, oil cakes, and from grains from other stores.
Treatment in bulk storage situations normally is carried out by fumigation, and in domestic situations finding the infested material, disposing of it and carrying out a residual spray to kill off stragglers.
Beetle
Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...
2.4–3 mm in size, with characteristic "teeth" running down the side of the prothorax
Prothorax
The prothorax is the foremost of the three segments in the thorax of an insect, and bears the first pair of legs. Its principal sclerites are the pronotum , the prosternum , and the propleuron on each side. The prothorax never bears wings in extant insects, though some fossil groups possessed...
. The sawtoothed grain beetle is a primary pest, in the UK, that attacks damaged grain. Carolus Linnaeus
Carolus Linnaeus
Carl Linnaeus , also known after his ennoblement as , was a Swedish botanist, physician, and zoologist, who laid the foundations for the modern scheme of binomial nomenclature. He is known as the father of modern taxonomy, and is also considered one of the fathers of modern ecology...
, the Swedish naturalist who defined taxonomic arrangements for the animal, plant, and mineral kingdoms acquired samples of the sawtoothed grain beetle from Suriname
Suriname
Suriname , officially the Republic of Suriname , is a country in northern South America. It borders French Guiana to the east, Guyana to the west, Brazil to the south, and on the north by the Atlantic Ocean. Suriname was a former colony of the British and of the Dutch, and was previously known as...
(Dutch Guiana) and named the species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
"Oryzaephilus surinamensis" because of this. (It is Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "rice-lover from Surinam".)
A relative of the sawtoothed grain beetle of the same genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
, the merchant grain beetle
Merchant grain beetle
The merchant grain beetle, Oryzaephilus mercator, is a slender, dark brown beetle.It can be found infesting biscuits and fruit and nut products. The adults can fly but rarely do...
, is more likely to be found in domestic dwellings since it requires higher more stable temperatures and can be found infesting biscuits and fruit and nut products. The adults can fly but rarely do. They can be differentiated by looking at the distance of the eye to the prothorax: with the merchant grain beetle it is less than half the vertical diameter of the eye.
The sawtoothed grain beetle lays its eggs loosely on foodstuffs at the rate of 6–10 per day, with total being 370 per female. The larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e are to be found within the mass of the foodstuff in the top centimetre or two. As mentioned above damaged cereal is entered through broken kernels, and the larvae feed on the germ
Cereal germ
The germ of a cereal is the reproductive part that germinates to grow into a plant; it is the embryo of the seed. Along with bran, germ is often a by-product of the milling that produces refined grain products. Cereal grains and their components, such as wheat germ, rice bran, and maize may be used...
, causing damage by reducing the percentage of grains which will germinate.
The total life cycle is 20–80 days at 18–37 °C (64.4–98.6 F).
The sawtoothed grain beetle can survive in unheated warehouses in the UK, and is considered the most important pest of home grown grain in the UK. The beetles survive the winter hiding in cracks and infest new stocks of grain the following year. Both insects are distributed throughout the world and regularly imported into the UK in unprocessed cereals, oil cakes, and from grains from other stores.
Treatment in bulk storage situations normally is carried out by fumigation, and in domestic situations finding the infested material, disposing of it and carrying out a residual spray to kill off stragglers.