Skin beetle
Encyclopedia
Dermestidae are a family of Coleoptera that are commonly referred to as skin beetles. Other common names include larder beetle, hide or leather beetles, carpet beetles, and khapra beetles. There are approximately 500 to 700 species worldwide. They can range in size from 1–12 mm. Key characteristics for adults are round oval shaped bodies covered in scales or setae. The (usually) clubbed antennae
fit into deep grooves. The hind femora
also fit into recesses of the coxa
. Larvae are scarabaeiform
and also have setae.
Dermestids have a variety of habits; most genera are scavenger
s that feed on dry animal or plant material such as skin or pollen
, animal hair, feathers, dead insects and natural fibers. Members of Dermestes
are found in animal carcasses, while others may be found in mammal
, bird
, bee
, or wasp
nests. Thaumaglossa only lives in the egg cases of mantids, while Trogoderma
species are pests of grain
.
These beetles are significant in forensic entomology
. Some species are known to be associated with decaying carcasses which help with criminal investigations. Some species are pests (urban entomology
) and can cause extensive damage to natural fibers in homes and businesses.
They are used in taxidermy and by natural history museum
s to clean animal skeletons. Some dermestid species, commonly called "bow bugs," infest violin
cases, feeding on the bow
hair.
occurs in a predictable succession. Adult D. maculatus beetles generally arrive 5 to 11 days after death. In an attempt to refine this relatively wide range, recent research has repeated arthropod succession studies. These studies are applied to estimate the arrival of various species of Dermestidae after death. Development for Dermestids is temperature dependent, and the optimal temperature for D. maculatus is 30˚C. Development data is normalized using Accumulated Degree Days
. Dermestids can also be used in cases involving entomotoxicology
, where feces and shed larval skins can be analyzed for toxins.
Dermestes maculatus collected from raccoon carcass:
, larva
, pupa
, and adult
stage. As opposed to ametabolous or hemimetabolous development, the larva's wings start off as internal wing pads and as development progresses, the wings begin to develop externally. Dermestid larvae are profoundly covered with varying lengths of setae that give a general "fluffy" appearance. The larvae are generally dark brown to black and possess a pair of spine like appendages on the terminal end of the abdomen
. Most beetle larvae have chewing mouthparts, an obvious head capsule which is sclerotized
, as well as 3 pairs of well developed thoracic
legs that easily distinguish them from Diptera
maggots. The larva's size depends on the species and is typically less than 1/2 of an inch. Most larvae are found on human corpses during the dry and skeletal phases of decomposition
, which occurs several days after death. Larvae also move away from light and often hide in any cavity in order to remain undisturbed.
The larder beetle, Dermestes lardarius, larva is longer than the adult larder beetle and thickly covered with short and long setae which are reddish-brown to black in color. Along with the coloration is a white undersurface. They also have two spine-like appendages on the posterior end on the abdominal segment. A distinguishing feature of the spine is that it curves backward. The black larder beetle larvae possess the same general characteristics but instead of the spines curving, they extend backward and are not strongly curved. Mature larvae of both species tend to bore into hard substrates such as wood, cork, and plaster in order to pupate.
Larder beetles are infrequent pests of households. Both adults and larvae feed on raw skins and hides. Adult larder beetles are generally 1/3 to 3/8 of an inch long and are dark brown with a broad, pale yellow spotted band across the upper portion of the elytra. Three black dots arrange in a triangle shape on each wing. The sternum
and legs of the larder beetle are covered in fine, yellow setae. Adult larder beetles are typically found outdoors in protected areas during the winter but during the spring and early summer they enter buildings. Females lay approximately 135 eggs near a food source and will hatch in about 12 days. The life cycle of larder beetles lasts around 40 to 50 days.
Hide beetles or leather beetles are also known as the skin beetles. Both adults and larvae of skin beetles feed on raw skins and hides like the larder beetles. This species is distributed worldwide. The hide or leather beetle is similar in appearance to the larder beetle except the forewings are only dark brown and the sternum is mostly white with some black, which is a characteristic feature. Their life cycle lasts 60 to 70 days and the females can lay up to 800 eggs in their lifetime.
The hide and larder beetles both feed on an assortment of animal protein based products and cause serious damage in the areas of silkworm production and museums.
, Attagenus megatoma, is a widely known stored product pest and one of the most destructive because the damage caused to household products containing keratin
, which is a protein found in animal hair and feathers. They are also able to burrow through various food packaging allowing passage for other insects as well. Females can lay up to 90 eggs and they hatch in about 8 to 15 days. Generally this species only has one generation a year. The time it takes to become an adult varies from 6 months to a year. In addition, an adult black carpet beetle can live up for an additional 2 months. The average adult size is about 2.8 to 5 mm long and they are oval, dark brown to shiny-black in color, and have brown legs.
, Anthrenus verbasci, attacks typical household objects. Carpet beetles are normally associated with things such as carpets, wool, furs, and any processed animal or plant food. Their appetite also includes dead insects, spiders, and even nectar and pollen. They are typically found throughout the United States
and Canada
. Females can lay up to 40 eggs and the number of larval instars range from 7–8 stages. The time it takes to become an adult varies from about 8 months to a year. In addition, the adults can live around 2 to 6 weeks. This species varies in shape, size, color, and pattern of scales. On average, the adults are 2 to 3 mm in length and have scales that vary from white, brown, yellow, or even gray-yellow.
, Trogoderma granarium, larvae contain characteristic body setae such as simple hairs and barbed hairs. Larvae are yellow-white but the head and body setae are brown. As the larvae further develop, their color changes to a golden or reddish brown and the abdomen portion becomes proportionally shorter. The mature larvae reach a maximum length of 6 mm long and 1.5 mm wide.
The khapra beetle is a stored-product pest. Infestations are difficult to control because they crawl into cracks and crevices, remaining for long periods of time. They tend to infest grains and create serious losses on stored products. The adults are covered with setae and are approximately 1.5 to 3 mm long and 1 to 2 mm wide. Male khapra beetles are brown to black with reddish brown markings on the elytra. Females are slightly larger than the males and are lighter in color. The short, 11 segmented antennae has a club of 3 to 5 segments, which fit into a groove on the side of the pronotum.
Application of insecticides must be spot treatment to crack and crevice sites where they are suspected of hiding. Pyrethrin
s are labeled for the use against hide beetles. Also insecticides used for carpet beetles are appropriate to use against hide and larder beetles.
Pyrethroid
insecticides can be use in order to control carpet beetles. Products containing active ingredients such as permethrin
, bifenthrin
, deltamethrin
, tralomethrin
are components of the Pyrethroid insecticide.
Diatomaceous earth is also effective.
Antenna (biology)
Antennae in biology have historically been paired appendages used for sensing in arthropods. More recently, the term has also been applied to cilium structures present in most cell types of eukaryotes....
fit into deep grooves. The hind femora
Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...
also fit into recesses of the coxa
Arthropod leg
The arthropod leg is a form of jointed appendage of arthropods, usually used for walking. Many of the terms used for arthropod leg segments are of Latin origin, and may be confused with terms for bones: coxa , trochanter , femur, tibia, tarsus, ischium, metatarsus, carpus, dactylus ,...
. Larvae are scarabaeiform
Scarabaeidae
The family Scarabaeidae as currently defined consists of over 30,000 species of beetles worldwide. The species in this large family are often called scarabs or scarab beetles. The classification of this family is fairly unstable, with numerous competing theories, and new proposals appearing quite...
and also have setae.
Dermestids have a variety of habits; most genera are scavenger
Scavenger
Scavenging is both a carnivorous and herbivorous feeding behavior in which individual scavengers search out dead animal and dead plant biomass on which to feed. The eating of carrion from the same species is referred to as cannibalism. Scavengers play an important role in the ecosystem by...
s that feed on dry animal or plant material such as skin or pollen
Pollen
Pollen is a fine to coarse powder containing the microgametophytes of seed plants, which produce the male gametes . Pollen grains have a hard coat that protects the sperm cells during the process of their movement from the stamens to the pistil of flowering plants or from the male cone to the...
, animal hair, feathers, dead insects and natural fibers. Members of Dermestes
Dermestes
Dermestes is a genus of larder beetles in the family Dermestidae. Both the adult beetles and the larvae feed on dry dead animals and vegetable material. Dermestes, especially its larvae, can seriously damage natural animal fibers, foodstuff, furnishing and zoological collections...
are found in animal carcasses, while others may be found in mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
, bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
, bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...
, or wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...
nests. Thaumaglossa only lives in the egg cases of mantids, while Trogoderma
Trogoderma
Trogoderma is a genus of beetles in the family Dermestidae....
species are pests of grain
Cereal
Cereals are grasses cultivated for the edible components of their grain , composed of the endosperm, germ, and bran...
.
These beetles are significant in forensic entomology
Forensic entomology
Forensic entomology is the application and study of insect and other arthropod biology to criminal matters. It is primarily associated with death investigations; however, it may also be used to detect drugs and poisons, determine the location of an incident, and find the presence and time of the...
. Some species are known to be associated with decaying carcasses which help with criminal investigations. Some species are pests (urban entomology
Home stored product entomology
Home stored product entomology is the study of insects which infest foodstuffs stored in the home. It deals with the prevention, detection and eradication of the pests...
) and can cause extensive damage to natural fibers in homes and businesses.
They are used in taxidermy and by natural history museum
Natural History Museum
The Natural History Museum is one of three large museums on Exhibition Road, South Kensington, London, England . Its main frontage is on Cromwell Road...
s to clean animal skeletons. Some dermestid species, commonly called "bow bugs," infest violin
Violin
The violin is a string instrument, usually with four strings tuned in perfect fifths. It is the smallest, highest-pitched member of the violin family of string instruments, which includes the viola and cello....
cases, feeding on the bow
Bow (music)
In music, a bow is moved across some part of a musical instrument, causing vibration which the instrument emits as sound. The vast majority of bows are used with string instruments, although some bows are used with musical saws and other bowed idiophones....
hair.
Urban and stored products
Dermestid beetles are destructive to a number of common items. Natural animal fibers such as wool, silk, fur, or feathers are more prone to attack than synthetic fibers. Dermestids are also known to attack chocolate, copra, and cocoa beans. Most damage is done by the larval stage of the beetle, while adults feed on flowers and shrubs.Medicolegal
Dermestes maculatus, hide beetles, also have the potential to offer investigators an estimation of the time since death in homicide or questionable cases. Similar to the use of flies in forensic entomology, the arrival of D. maculatus to carrionCarrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
occurs in a predictable succession. Adult D. maculatus beetles generally arrive 5 to 11 days after death. In an attempt to refine this relatively wide range, recent research has repeated arthropod succession studies. These studies are applied to estimate the arrival of various species of Dermestidae after death. Development for Dermestids is temperature dependent, and the optimal temperature for D. maculatus is 30˚C. Development data is normalized using Accumulated Degree Days
Degree day
A degree day is a measure of heating or cooling. Totalized degree days from an appropriate starting date are used to plan the planting of crops and management of pests and pest control timing...
. Dermestids can also be used in cases involving entomotoxicology
Entomotoxicology
In forensic entomology, entomotoxicology is the analysis of toxins in arthropods that feed on carrion. Using arthropods in a corpse or at a crime scene, investigators can determine whether toxins were present in a body at the time of death...
, where feces and shed larval skins can be analyzed for toxins.
Dermestes maculatus collected from raccoon carcass:
General larval characteristics
Dermestid larvae boast a complete or holometabolous development, which include an eggEgg (biology)
An egg is an organic vessel in which an embryo first begins to develop. In most birds, reptiles, insects, molluscs, fish, and monotremes, an egg is the zygote, resulting from fertilization of the ovum, which is expelled from the body and permitted to develop outside the body until the developing...
, 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...
, pupa
Pupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
, and adult
Adult
An adult is a human being or living organism that is of relatively mature age, typically associated with sexual maturity and the attainment of reproductive age....
stage. As opposed to ametabolous or hemimetabolous development, the larva's wings start off as internal wing pads and as development progresses, the wings begin to develop externally. Dermestid larvae are profoundly covered with varying lengths of setae that give a general "fluffy" appearance. The larvae are generally dark brown to black and possess a pair of spine like appendages on the terminal end of the abdomen
Abdomen
In vertebrates such as mammals the abdomen constitutes the part of the body between the thorax and pelvis. The region enclosed by the abdomen is termed the abdominal cavity...
. Most beetle larvae have chewing mouthparts, an obvious head capsule which is sclerotized
Sclerosis (medicine)
In medicine, sclerosis refers to the stiffening of a structure, usually caused by a replacement of the normal organ-specific tissue with connective tissue.Types include:...
, as well as 3 pairs of well developed thoracic
Thorax (insect anatomy)
The thorax is the mid section of the insect body. It holds the head, legs, wings and abdomen. It is also called mesosoma in other arthropods....
legs that easily distinguish them from Diptera
Diptera
Diptera , or true flies, is the order of insects possessing only a single pair of wings on the mesothorax; the metathorax bears a pair of drumstick like structures called the halteres, the remnants of the hind wings. It is a large order, containing an estimated 240,000 species, although under half...
maggots. The larva's size depends on the species and is typically less than 1/2 of an inch. Most larvae are found on human corpses during the dry and skeletal phases of decomposition
Decomposition
Decomposition is the process by which organic material is broken down into simpler forms of matter. The process is essential for recycling the finite matter that occupies physical space in the biome. Bodies of living organisms begin to decompose shortly after death...
, which occurs several days after death. Larvae also move away from light and often hide in any cavity in order to remain undisturbed.
Larder beetles
Larder beetles are infrequent pests of households. Both adults and larvae feed on raw skins and hides. Adult larder beetles are generally 1/3 to 3/8 of an inch long and are dark brown with a broad, pale yellow spotted band across the upper portion of the elytra. Three black dots arrange in a triangle shape on each wing. The sternum
Sternum (arthropod)
The sternum is the ventral portion of a segment of an arthropod thorax or abdomen.In insects, the sterna are usually single, large sclerites, and external...
and legs of the larder beetle are covered in fine, yellow setae. Adult larder beetles are typically found outdoors in protected areas during the winter but during the spring and early summer they enter buildings. Females lay approximately 135 eggs near a food source and will hatch in about 12 days. The life cycle of larder beetles lasts around 40 to 50 days.
Black larder or incinerator beetle
The black larder or incinerator beetle, Dermestes ater, is completely dark with scattered yellow setae on the body. They are similar to Dermestes maculatus but lack a serrated elytra. A distinctive feature is the ventral pattern is yellow instead of white. This beetle is a severe pest of fish, mushrooms, and cheese.Hide/leather beetle
The hide/leather beetle, Dermestes maculatus, larvae are longer than their adult beetles. They are slim and altogether covered with short and long setae. As compared to the larder beetle, they are reddish-brown to black in color. In addition, they also possess two spine like appendages on their posterior end on their abdomen. An identifying feature about the spine is that it curves forward unlike the larder beetle.Hide beetles or leather beetles are also known as the skin beetles. Both adults and larvae of skin beetles feed on raw skins and hides like the larder beetles. This species is distributed worldwide. The hide or leather beetle is similar in appearance to the larder beetle except the forewings are only dark brown and the sternum is mostly white with some black, which is a characteristic feature. Their life cycle lasts 60 to 70 days and the females can lay up to 800 eggs in their lifetime.
The hide and larder beetles both feed on an assortment of animal protein based products and cause serious damage in the areas of silkworm production and museums.
Carpet beetle
The carpet beetle larvae start to feed as soon as they hatch. They are carrot shaped and heavily covered with setae especially in their posterior end. The number of instars differ from 5–11 and in some cases reach up to 20. The black carpet beetle, Attagenus megatoma, larvae may grow up to 1/2 inch (12 mm) and be yellow to brown in color. Other types of carpet beetles are regularly 1/4 to 1 inch (6 to 25 mm) in length and covered with dark setae. Certain species have distinctive tufts of setae extending from their posterior end. These beetles are attracted to soiled fabrics and crevices where dead insects may serve as a food source. The larvae of the carpet beetle are often referred to as "woolly bears" or "buffalo moths".Black carpet beetle
The black carpet beetleBlack carpet beetle
The black carpet beetle, Attagenus unicolor, is a beetle, long, that can be a serious household pest. The larvae grow to in length, are reddish brown in colour and covered with bristles. The larval form feeds on natural fibres, damaging carpets, furniture and clothing.-External links:* on the UF...
, Attagenus megatoma, is a widely known stored product pest and one of the most destructive because the damage caused to household products containing keratin
Keratin
Keratin refers to a family of fibrous structural proteins. Keratin is the key of structural material making up the outer layer of human skin. It is also the key structural component of hair and nails...
, which is a protein found in animal hair and feathers. They are also able to burrow through various food packaging allowing passage for other insects as well. Females can lay up to 90 eggs and they hatch in about 8 to 15 days. Generally this species only has one generation a year. The time it takes to become an adult varies from 6 months to a year. In addition, an adult black carpet beetle can live up for an additional 2 months. The average adult size is about 2.8 to 5 mm long and they are oval, dark brown to shiny-black in color, and have brown legs.
Varied carpet beetle
The varied carpet beetleVaried carpet beetle
The varied carpet beetle is a 3 mm–long beetle that can be a serious household pest. It feeds on natural fibers and can damage carpets, furniture and clothing....
, Anthrenus verbasci, attacks typical household objects. Carpet beetles are normally associated with things such as carpets, wool, furs, and any processed animal or plant food. Their appetite also includes dead insects, spiders, and even nectar and pollen. They are typically found throughout the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
and Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
. Females can lay up to 40 eggs and the number of larval instars range from 7–8 stages. The time it takes to become an adult varies from about 8 months to a year. In addition, the adults can live around 2 to 6 weeks. This species varies in shape, size, color, and pattern of scales. On average, the adults are 2 to 3 mm in length and have scales that vary from white, brown, yellow, or even gray-yellow.
Khapra beetle
Upon hatching the larvae are around 1.6 to 1.8 mm long and mostly filled with dense setae. Khapra beetleKhapra beetle
The Khapra beetle , which originated in South Asia, is one of the world’s most destructive pests of grain products and seeds. It is considered one of the 100 worst invasive species in the world...
, Trogoderma granarium, larvae contain characteristic body setae such as simple hairs and barbed hairs. Larvae are yellow-white but the head and body setae are brown. As the larvae further develop, their color changes to a golden or reddish brown and the abdomen portion becomes proportionally shorter. The mature larvae reach a maximum length of 6 mm long and 1.5 mm wide.
The khapra beetle is a stored-product pest. Infestations are difficult to control because they crawl into cracks and crevices, remaining for long periods of time. They tend to infest grains and create serious losses on stored products. The adults are covered with setae and are approximately 1.5 to 3 mm long and 1 to 2 mm wide. Male khapra beetles are brown to black with reddish brown markings on the elytra. Females are slightly larger than the males and are lighter in color. The short, 11 segmented antennae has a club of 3 to 5 segments, which fit into a groove on the side of the pronotum.
Hide and larder beetles
Modern methods of meat slaughtering, storage, and distribution have reduced potential infestations of hide beetles. Proper housekeeping is crucial for the prevention of infestations. Dead insects in homes usually attract these beetles because they are a prime food source for hide and larder beetles. Food must be tightly sealed or stored in a refrigerator to avoid any beetle access. Freezing food for a week, heating meat in a pan or microwave for prolonged lengths can kill these insects found in infested foods and prevent them from spreading.Application of insecticides must be spot treatment to crack and crevice sites where they are suspected of hiding. Pyrethrin
Pyrethrin
The pyrethrins are a pair of natural organic compounds that have potent insecticidal activity. Pyrethrins are neurotoxins that attack the nervous systems of all insects. When present in amounts not fatal to insects, they still appear to have an insect repellent effect. Pyrethrins are gradually...
s are labeled for the use against hide beetles. Also insecticides used for carpet beetles are appropriate to use against hide and larder beetles.
Carpet beetles
Regular cleaning of spilled food or lint will eliminate any sites for potential breeding. Susceptible items like food, woolens, and furs should be stored in an insect proof container. If an infestation is suspected then the source of the problem must be removed and destroyed to further limit any possibility of spreading. These beetles can be killed with extreme heat or exposure to freezers.Pyrethroid
Pyrethroid
A pyrethroid is an organic compound similar to the natural pyrethrins produced by the flowers of pyrethrums . Pyrethroids now constitute a major commercial household insecticides...
insecticides can be use in order to control carpet beetles. Products containing active ingredients such as permethrin
Permethrin
Permethrin is a common synthetic chemical, widely used as an insecticide, acaricide, and insect repellent. It belongs to the family of synthetic chemicals called pyrethroids and functions as a neurotoxin, affecting neuron membranes by prolonging sodium channel activation. It is not known to...
, bifenthrin
Bifenthrin
Bifenthrin is a pyrethroid insecticide that affects the nervous system of insects.It was discovered and developed by FMC Corporation. Products containing bifenthrin include Talstar, Maxxthor, Capture, Brigade, Bifenthrine, Ortho Home Defense Max, Bifen IT, Bifen L/P, and Scotts LawnPro Step...
, deltamethrin
Deltamethrin
Deltamethrin is a pyrethroid ester insecticide.-Usage:Deltamethrin products are among the most popular and widely used insecticides in the world and have become very popular with pest control operators and individuals in the United States in the past five years. This material is a member of one of...
, tralomethrin
Tralomethrin
Tralomethrin is a pyrethroid insecticide.Tralomethrin has potent insecticidal properties; it kills by modifying the gating kinetics of the sodium channels in neurons, increasing the length of time the channel remains open after a stimulus, thereby depolarizing the neuron for a longer period of...
are components of the Pyrethroid insecticide.
Diatomaceous earth is also effective.
External links
- Dermestidae of the World
- List of North American Species
- Dermestidae-Literature
- Russian Atlas of Carpet Beetles-excellent images
- USDA Leaflet on Carpet beetles
- on the UFUniversity of FloridaThe University of Florida is an American public land-grant, sea-grant, and space-grant research university located on a campus in Gainesville, Florida. The university traces its historical origins to 1853, and has operated continuously on its present Gainesville campus since September 1906...
/ IFASInstitute of Food and Agricultural SciencesThe University of Florida’s Institute of Food and Agricultural Sciences is a federal-state-county partnership dedicated to developing knowledge in agriculture, human and natural resources, and the life sciences, and enhancing and sustaining the quality of human life by making that information...
Featured Creatures Web site - Carpet Beetles, Kansas State University