The Strepsiptera are an order of insects with nine extant families that include about 600 described species. They are endoparasites in other insects, such as bees, wasps, leafhoppers, silverfish, and cockroaches. Females of most species never emerge from the host after entering its body, finally dying inside it. The early-stage larvae do emerge because they must find an unoccupied living host, and the short-lived males must emerge to seek a receptive female in her host. They are believed to be most closely related to beetles, from which they diverged 300–350 million years ago, but do not appear in the fossil record until the mid-Cretaceous around 100 million years ago.
The whirligig beetles are water beetles, comprising the family Gyrinidae that usually swim on the surface of the water if undisturbed, though they swim 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 plain 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. Whirligig beetles belong to the beetle suborder Adephaga, which also includes ground beetles and diving beetles.
The telephone-pole beetle is a beetle native to the eastern United States, and the only living representative of the otherwise extinct family Micromalthidae. They have an unusual lifecycle involving asexually reproducing (parthenogenetic) female larvae, as well as non-functional "ghost adults".
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.
Rhysodidae is a family of beetles, consisting of more than 350 species in about 20 genera.
The longhorn beetles (Cerambycidae), also known as long-horned or longicorns, are a large family of beetles, with over 35,000 species described. Most species are 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 and such species can be difficult to distinguish from related beetle families such as the Chrysomelidae. The scientific name of this beetle family goes back to a figure from Greek mythology: after an argument with nymphs, the shepherd Cerambus was transformed into a large beetle with horns.
Myxophaga is the second-smallest suborder of the Coleoptera after Archostemata, consisting of roughly 65 species of small to minute beetles in four families. The members of this suborder are aquatic and semiaquatic, and feed on algae.
The Tenebrionoidea are a very large and diverse superfamily of beetles. It generally corresponds to the Heteromera of earlier authors.
The Lymexylidae, also known as ship-timber beetles, are a family of wood-boring beetles. Lymexylidae belong to the suborder Polyphaga and are the sole member of the superfamily Lymexyloidea.
The family Oedemeridae is a cosmopolitan group of beetles commonly known as false blister beetles, though some recent authors have coined the name pollen-feeding beetles. There are some 100 genera and 1,500 species in the family, mostly associated with rotting wood as larvae, though adults are quite common on flowers. The family was erected by Pierre André Latreille in 1810.
Ripiphoridae is a cosmopolitan family of some 450 described species of beetles sometimes called "wedge-shaped beetles". Ripiphoridae are unusual among beetle families in that many species are hypermetamorphic parasitoids, an attribute that they share with the Meloidae. Members of the family differ in their choice of hosts, but most attack various species of bees or wasps, while some others attack cockroaches or beetles. Many species of Ripiphoridae have abbreviated elytra, and flabellate or pectinate antennae.
Syntelia is a genus of middle-sized beetles described by John O. Westwood in 1864. It is the only genus in the family Synteliidae erected by George Lewis in 1882. There are seven known species, which are native to high-elevation regions in southern North America from central Mexico to Guatemala, and in eastern Asia, from India to Japan and eastern Russia. They are generally associated with rotting logs, typically found under bark, thought the Mexican species S. westwoodi has been found inside large decaying columnar cacti. Adults and larvae are predatory, feeding on insect larvae. A fossil species, Syntelia sunwukong, is known from the Late Cretaceous (Cenomanian) aged Burmese amber of Myanmar. The characteristics of the family and genus include geniculate antennae with 3-segmented club, elongate body, narrowly separated coxae and tarsi with bisetose empodia. Only one abdominal segment is exposed behind elytra. They are members of Histeroidea, which also includes clown beetles (Histeridae).
Lepicerus is a genus of myxophagan beetles containing three described species in the family Lepiceridae; it is the only extant genus in the family, with another genus, Lepiceratus only known from fossils. Extant species occur in the Neotropics, from Mexico south to Venezuela and Ecuador. Fossils referrable to the genus are known from the early Late Cretaceous of Southeast Asia.
Helotidae is a family of beetles, in the suborder Polyphaga. The family includes about five extant genera, Helota MacLeay, Neohelota Ohta, Afrohelotina Kirejtshuk, Metahelotella Kirejtshuk, and Strophohelota Kirejtshuk. Helotidae are found mainly in the Old World tropics and are absent from Australia and Madagascar. The antennae are clubbed on the final three segments and is retractable within grooves under the head. The wings have reduced venation with just 4 anal veins. Helotids are known to be associated with sap, fruit and flowers, and the larvae of some species are known to bore into wood in order to pupate.
Smicripidae is a family of beetles, in the superfamily Cucujoidea. The common name for this family is palmetto beetles. The family only has one extant genus, Smicrips, with six extant species native to tropical and subtropical regions of the Americas and extinct species from the Eocene of Europe and one extinct genus, Mesosmicrips, known from the mid Cretaceous aged Burmese amber. Smicrips larvae are usually found amongst decaying vegetation, while adults are typically found on infloresences, especially those of Arecaceae (palms), althought associations with flowers of Fabaceae (legumes), Passifloraceae, Bombacaceae and Cactaceae (cactus) have also been recorded. Their diet is unknown.
The Brachypsectridae are a family of beetles commonly known as the Texas beetles. There are only two extant genera, Brachypsectra and Asiopsectra. Brachypsectra has a cosmopolitan distribution, mostly in arid regions, while Asiopsectra is found in Central Asia and the Middle East.
Passandridae, the "parasitic flat bark beetles," are a family of beetles notable for being one of the very few beetle families with larvae that are, as far as known, exclusively ectoparasitic on the immature stages of other beetles and Hymenoptera.
Eucnemidae, or false click beetles, are a family of elateroid beetles including about 1700 species distributed worldwide.
Throscidae is a family of elateroid beetles found worldwide with around 150 species in 5 extant genera. The larvae are soil-dwelling, siphoning fluid from mycorrhizae attached to trees. The adults are short-lived, with the adult males being noted for a complex mating dance. Like some other elateroids, they are capable of clicking.
Peltis is a genus of beetles found in North America and Europe, and the sole extant member of the family Peltidae, formerly included in the Trogossitidae. Members of this genus are dark, averaging from brown, to dark brown, to black. They are small, wide, and flat-bodied with wide, ridged elytra. Fossil species of this genus are known from the Eocene aged Florissant Formation of the United States, as well as the Baltic amber of Europe.
