Passalidae is a family of beetles known variously as "bessbugs", "bess beetles", "betsy beetles" or "horned passalus beetles". Nearly all of the 500-odd species are tropical; species found in North America are notable for their size, ranging from 20–43 mm, for having a single "horn" on the head, and for a form of social behavior unusual among beetles.
The rove beetles are a family (Staphylinidae) of beetles, primarily distinguished by their short elytra that typically leave more than half of their abdominal segments exposed. With roughly 63,000 species in thousands of genera, the group is currently recognized as the largest extant family of organisms. It is an ancient group, with fossilized rove beetles known from the Triassic, 200 million years ago, and possibly even earlier if the genus Leehermania proves to be a member of this family. They are an ecologically and morphologically diverse group of beetles, and commonly encountered in terrestrial ecosystems.
Lutrochidae is a family of water beetles sometimes known as "travertine beetles", since in North America they are common in springs and streams depositing travertine.
The Trachypachidae are a family of beetles that generally resemble small ground beetles, but that are distinguished by the large coxae of their rearmost legs. There are only six known extant species in the family, with four species of Trachypachus found in northern Eurasia and northern North America, and two species of Systolosoma in Chile. They were much more diverse in the past, with many members belonging to the extinct subfamily Eodromeinae, the first fossils known of this family are of the genera Petrodromeus and Permunda from the Permian-Triassic boundary of Russia.
Sphaerites is a genus of beetles, the only genus in the family Sphaeritidae, sometimes called the false clown beetles. It is closely related to the clown beetles but with distinct characteristics. There are five known species, widespread in temperate area but not commonly seen.
The Cucujidae, "flat bark beetles," are a family of distinctively flat beetles found worldwide under the bark of dead trees. The family has received considerable taxonomic attention in recent years and now consists of 59 species distributed in four genera.
Derodontidae is a family of beetles, in its own superfamily, Derodontoidea, sometimes known as the tooth-necked fungus beetles. Beetles of this family are small, between 2 and 6 mm in length, with spiny margins on their pronotum that give them their name. The genus, Laricobius, lacks these spines. They have two ocelli on the top of their heads.
The family Archeocrypticidae is a small group of beetles with no vernacular common name, though recent authors have coined the name cryptic fungus beetles. Adults and larvae seems to be saprophagous and are often found in plant litter. Worldwide, about 10 genera and 50 species are found, most species are pantropical. Enneboeus caseyi has been recorded from the American South, Central America, and Mexico. About 20 species are found in Australia, in the genera Enneboeus and Australenneboeus.
The Boridae are a small family of beetles with no vernacular common name, though recent authors have coined the name conifer bark beetles.
Syntelia is a genus of middle-sized beetles, the only genus in the family Synteliidae.
Georissus, also called minute mud-loving beetles, is the only genus in the beetle family Georissidae. They are tiny insects living in wet soil, often near water. Found on every continent except Antarctica.
Calosoma is a genus of large ground beetles that occur primarily throughout the Northern Hemisphere, and are referred to as caterpillar hunters or searchers. Many of the 167 species are largely or entirely black, but some have bright metallic coloration. They produce a foul-smelling spray from glands near the tip of the abdomen. They are recognizable due to their large thorax, which is almost the size of their abdomen and much wider than their head.
Chlaenius is a large and diverse genus of ground beetle. It is native to the Palearctic, the Near East, North Africa, Afrotropical region, and the Nearctic. Worldwide, roughly 1,000 species are currently recognized with the majority of known species occurring in the Oriental and Afrotropical regions. The genus is divided into many subgenera.
Meruidae is a recently described family of aquatic beetles in the suborder Adephaga, with only one genus and species, Meru phyllisae. This beetle species was first found in the early 1980s. At 0.8 mm, it is one of the smallest adephagan beetles in the world. A recent survey of aquatic beetles of Venezuela prove that Meru is most common during the wet season, when larger areas of granitic rock surface are covered with water film, which the adult beetles as well as the larvae inhabit.
Bothrideridae is a family of beetles in the suborder Polyphaga. They are known commonly as the cocoon-forming beetles or dry bark beetles. They occur worldwide with most native to the Old World tropics.
Laemophloeidae, "lined flat bark beetles," is a family in the superfamily Cucujoidea characterized by predominantly dorso-ventrally compressed bodies, head and pronotal discs bordered by ridges or grooves, and inverted male genitalia. Size range of adults is 1–5 mm (0.04–0.2 in) in length. Currently, it contains 40 genera and about 450 species, and is represented on all continents except Antarctica; species richness is greatest in the tropics.
Silvanidae, "silvan flat bark beetles", is a family of beetles in the superfamily Cucujoidea, consisting of 58 described genera and about 500 described species. The family is represented on all continents except Antarctica, and is most diverse at both the generic and species levels in the Old World tropics.
Byturidae, also known as Fruitworms, is a very small family of beetles, in the suborder Polyphaga, comprising fewer than 20 species worldwide. The larvae of some species develop in fruits. Byturus unicolor affects species of Rubus and Geum.
Clambidae is a family of beetles. They are known commonly as the minute beetles or the fringe-winged beetles. They are found worldwide on every continent except Antarctica.
Gigaductus is a genus of parasites in the phylum Apicomplexa.
