The Beetles (Order Coleoptera) of Southern California

Amphizoa is a genus of beetles, placed in its own family, Amphizoidae. The vernacular name "trout-stream beetle" comes from the original finding of A. insolens and A. lecontei in high mountain streams, although other species occur at lower elevation. They are notable as a possible intermediate stage between terrestrial and aquatic beetles; while living in the water, they are not good swimmers and physically resemble ground beetles more than other types of water beetle. less ↑

Dytiscidae – based on the Greek dytikos (δυτικός), "able to dive" – are the predaceous diving beetles, a family of water beetles. They are about 25 mm (one inch) long on average, though there is much variation between species. Dytiscus latissimus, the largest, can grow up to 45 mm long. Most are dark brown, blackish or dark olive in color with golden highlights in some subfamilies. They have short, but sharp mandibles. Immediately upon biting they deliver digestive enzymes. The larvae are commonly known as water tigers. The family has not been comprehensively cataloged since 1920, but is estimated to include about 4,000 species in over 160 genera. less ↑

The whirligig beetles are a family (Gyrinidae) of water beetles that usually swim on the surface of the water if undisturbed, though they swim actively underwater when threatened. They get their common name from their habit of swimming rapidly in circles when alarmed, and are also notable for their divided eyes which are believed to enable them to see both above and below water. The family includes some 700 extant species worldwide, in 15 genera, plus a few fossil species. Most species are very similar in general appearance, though they vary in size from perhaps 3 mm to 18 mm in length. They tend to be flattened and rounded in cross section, in plan view as seen from above, and in longitudinal section. In fact their shape is a good first approximation to an ellipsoid, with legs and other appendages fitting closely into a streamlined surface. less ↑

The Haliplidae are a family of water beetles who swim using an alternating motion of the legs. They are therefore clumsy in water (compared e.g. with the Dytiscidae or Hydrophilidae), and prefer to get around by crawling. The family consists of about 200 species in 5 genera, distributed wherever there is freshwater habitat; it is the only extant member of superfamily Haliploidea. They are also known as crawling water beetles or haliplids. less ↑

The Trachypachidae (or sometimes false ground beetles) are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. Only six species are known in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile. less ↑

Histeridae is a family of beetles commonly known as Clown beetles or Hister beetles. This very diverse group of beetles contains 3,900 species found worldwide. They can be easily identified by their shortened elytra that leaves two of the seven tergites exposed, and their elbowed antennae with clubbed ends. These predatory feeders are most active at night and will fake death if they feel threatened. This family of beetles will occupy almost any kind of niche throughout the world. Hister beetles have proved useful during forensic investigations to help in time of death estimation. Also, certain species are used in the control of livestock pests that infest dung and to control houseflies. Because they are predacious and will even eat other Hister beetles, they must be isolated when collected. less ↑

Hydrophilidae, also called water scavenger beetles, is a family of chiefly aquatic beetles. Aquatic hydrophilids are notable for their long maxillary palpi, which are longer than their antennae. Several of the former subfamilies of Hydrophilidae have recently been removed and elevated to family rank; Epimetopidae, Georissidae (= Georyssinae), Helophoridae, Hydrochidae, and Spercheidae (= Sphaeridiinae). Some of these formerly-included groups are primarily terrestrial or semi-aquatic. less ↑

Water-penny beetles are a family (Psephenidae) of aquatic beetles. The young, which live in water, resemble pennies. The larvae feed off of algae, larvae, and feces. The presence of water penny larvae in a stream can be used as a test for the quality of the water. Among the pollution sensitivity categories sensitive, somewhat-sensitive, and tolerant; water pennies belong to the sensitive category. They cannot live in habitats where rocks acquire a thick layer of algae, fungi, or inorganic sediment. Therefore, their presence along with other diverse phyla signifies good quality water. They are around 6 to 10 millimeters in length. less ↑

The longhorn beetles (Cerambycidae; also known as long-horned beetles or longicorns) are a cosmopolitan family of beetles, typically characterized by extremely long antennae, which are often as long as or longer than the beetle's body. In various members of the family, however, the antennae are quite short (e.g., Neandra brunnea, figured below) and such species can be difficult to distinguish from related beetle families such as Chrysomelidae. The family is large, with over 20,000 species described, slightly more than half from the Eastern Hemisphere. Several are serious pests. The larvae, called roundheaded borers, bore into wood, where they can cause extensive damage to either living trees or untreated lumber (or, occasionally, to wood in buildings; the old-house borer, Hylotrupes bajulus, being a particular problem indoors). A number of species mimic ants, bees, and wasps, though a majority of species are cryptically colored. The rare titan beetle (Titanus giganteus) from northeastern South America is often considered the largest (though not the heaviest, and not the longest including legs) insect, with a maximum known body length of just over 16.7 centimetres (6.6 in). less ↑

The Megalopodidae are a small family of leaf beetles, previously included as a subfamily within the Chrysomelidae. One of its constituent subfamilies, Zeugophorinae, which contains a single genus, has also frequently been treated as a subfamily within Chrysomelidae. The family contains approximately 30 genera worldwide, primarily in the nominate subfamily Megalopodinae, and mostly circumtropical. less ↑

The soldier beetles, Cantharidae, are relatively soft-bodied, straight-sided beetles, related to the Lampyridae or firefly family, but unable to produce light. They are cosmopolitan in distribution. One common British species is bright red, reminding people of the red coats of soldiers, hence the common name. A secondary common name is leatherwing, obtained from the texture of the wing covers. less ↑

Insects in the family Elateridae are commonly called click beetles (or "typical click beetles" to distinguish them from the related Cerophytidae and Eucnemidae). Other names include elaters, snapping beetles, spring beetles or "skipjacks". This family was defined by William Elford Leach (1790-1836) in 1815. They are a cosmopolitan beetle family characterized by the unusual click mechanism they possess. There are a few closely related families in which a few members have the same mechanism, but all... less ↑

Lampyridae is a family of insects in the beetle order Coleoptera. They are winged beetles, and commonly called fireflies or lightning bugs for their conspicuous crepuscular use of bioluminescence to attract mates or prey. Fireflies produce a "cold light", with no infrared or ultraviolet frequencies. This chemically produced light from the lower abdomen may be yellow, green, or pale red, with wavelengths from 510 to 670 nanometers. less ↑

The Bostrichidae are a family of beetles with more than 700 described species. They are commonly called auger beetles, false powderpost beetles or horned powderpost beetles. The head of most auger beetles cannot be seen from above, as it is downwardly directed and hidden by the thorax. Exceptions are the powderpost beetles (subfamily Lyctinae), and members of the subfamily Psoinae. less ↑

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.... less ↑

The family Mycteridae is a small group of beetles with no vernacular common name, though recent authors have coined the name palm and flower beetles. The family Mycteridae is distributed worldwide. There are about 30 genera and 160 species. About 20 species are found in Australian, species of three genera are found in North America (Mycterus, Hemipeplus and Lacconotus) less ↑

The family Prostomidae is a small group of beetles with no vernacular common name, though recent authors have coined the name jugular-horned beetles. They are often found in dead wood. The family consist of two genera with about 20 species. Prostomis mandibularis is known from North America. Other species of Prostomis are found in Africa, the Pacific region and East Asia. Species of Dryocora are known from New Zealand, Australia and Tasmania. less ↑

The family Ripiphoridae (formerly spelled Rhipiphoridae) is a cosmopolitan group of beetles, commonly known as wedge-shaped beetles, containing some 450 species. Unusually for beetles, many ripiphorids are parasitoids—different groups within the family attack different hosts, but most are associated with bees or vespid wasps, while some others are associated with cockroaches. They often have abbreviated elytra, and branched (flabellate or pectinate) antennae. Genera include Allocinops, Rhipistena and Sharpides. less ↑

Zopheridae is a family of beetles that has grown considerably in recent years as the members of two other families have been included within its circumscription; these former families are the Monommatidae and the Colydiidae, which are now both included in the Zopheridae as subfamilies or (in the former case) even as tribe of subfamily Zopherinae. Some authors accept up to 6 subfamilies here, while others merge all except the Colydiinae into the Zopherinae. less ↑

Geotrupidae (from Greek geos, earth, and trypetes, borer) is a family of beetles in the order Coleoptera. They are commonly called earth-boring dung beetles. Most excavate burrows in which to lay their eggs. They are typically detritivores, provisioning their nests with leaf litter (often moldy), but are occasionally coprophagous, similar to dung beetles. The eggs are laid in or upon the provision mass and buried, and the developing larvae feed upon the provisions. The burrows of... less ↑

Glaresis is a genus of beetles, sometimes called "enigmatic scarab beetles", in its own family, the Glaresidae. It is closely related to, and was formerly included in, the family Scarabaeidae. Although its members occur in arid and sandy areas worldwide (except Australia), only the nocturnal adults have ever been collected (typically at lights), and both the larvae and biology of Glaresis are as yet unknown. Due to their narrow habitat associations, a great number of these... less ↑

The rain beetles are a group of beetles found in the far west of North America. They spend most of their lives underground, emerging in response to rain or snow, thus the common name. Formerly classified in the Geotrupidae, they are currently assigned to their own family Pleocomidae, considered the sister group to all the remaining families of Scarabaeoidea. The family contains a single extant genus, Pleocoma, and one extinct genus, Cretocoma, described in 2002 from Late Cretaceous deposits in Mongolia. less ↑

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 often. It is probable that many of the subfamilies listed here will not be recognized very much longer, as they will likely be reduced in status below subfamily rank, or elevated to family status (the latter is most likely, e.g., with the family "Melolonthidae" already appearing in some recent classifications). Other families have been removed recently, and are nearly universally accepted (e.g., Pleocomidae, Glaresidae, Glaphyridae, Ochodaeidae, Geotrupidae, and Bolboceratidae). less ↑

Ptiliidae is a family of very tiny beetles with a cosmopolitan distribution. This family contains the smallest of all beetles, with a length when fully grown of 0.3–4.0 millimetres (0.01–0.16 in). The weight is approximately 0.4 milligrams. They are colloquially called featherwing beetles, because the hindwings are narrow and feathery. The eggs are very large in comparison to the adult female (maybe half the length) so only one egg at a time can be developed and laid.Parthenogenesis is... less ↑

Silphidae is a family of beetles that are known commonly as large carrion beetles, carrion beetles or burying beetles. There are two subfamilies: Silphinae and Nicrophorinae. Nicrophorines are sometimes known as sexton beetles. The number of species is relatively small and around two hundred. They are more diverse in the temperate region although a few tropical endemics are known. Both families feed on decaying organic matter such as dead animals. The families differ in which uses... less ↑

The rove beetles are a family (Staphylinidae) of beetles, primarily distinguished by their short elytra that leave more than half of their abdomens exposed. With approximately 58,000 species in thousands of genera, the group is currently recognized as the largest family of beetles. It is an ancient group, with fossil rove beetles known from the Triassic, 200 million years ago, and possibly even earlier if the recently described Leehermania proves to be a member of this... less ↑

Cerylonidae is a family of beetles, in the suborder Polyphaga.The Cerylonidae are a family of small to minute beetles (usually 2 mm. 01- less) which occur most commonly in forest litter and under bark. At present, there are about 40 genera and over 300 described species known from all of the major zoogeographic regions. Crowson (1955) first recognized the Cerylonidae as an independent clavicorn family, including the cerylonines and murmidiines, as well as Euxes- tus and... less ↑

The Coccinellidae are a family of small beetles, ranging from 1 to 10 mm (0.04 to 0.4 inches). They are commonly yellow, orange, or scarlet with small black spots on their wing covers, with black legs, heads and antennae. Such colour patterns vary greatly, however; for example, a minority of species, such as Vibidia duodecimguttata, a twelve-spotted species, have whitish spots on a brown background. Coccinellids are found worldwide, with over 5,000 species described, more than 450 native... less ↑

Cryptophagidae is a family of beetles with representatives found in all ecozones. Members of this family are commonly called silken fungus beetles and both adults and larvae appear to feed exclusively on fungi although in a wide variety of habitats and situations, such as rotting wood and shed animal fur and feathers. These beetles vary from about 1 to 11 millimeters long, and usually have an oval body shape with a slight "waist". less ↑

Erotylidae, or the pleasing fungus beetles, is a family of beetles containing over 100 genera. In the present circumscription, it includes the subfamilies Dacninae, Encaustinae, Erotylinae, Megalodacninae, and Tritominae. In other words, the narrowly-circumscribed Erotylidae correspond to the subfamily Erotylinae in the definition sensu lato. They feed on plant and fungal matter; some are important pollinators (e.g. of the ancient cycads), while a few have gained notoriety as pests of some significance. Sometimes, useful and harmful... less ↑

The Attelabidae is a widespread family of weevils. They are among the primitive weevils, because of their straight antennae, which are inserted near the base of the rostrum. The prothorax is much narrower than the base of the elytra on the abdomen. Attelabidae and the related family Rhynchitidae are known commonly as the leaf-rolling weevils. Rhynchitidae may be treated as subfamily Rhychitinae of the Attelabidae. less ↑