 | This article needs additional citations for verification .(June 2015) |
| Scymnini | |
|---|---|
 | |
| Stethorus punctillum | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Arthropoda |
| Class: | Insecta |
| Order: | Coleoptera |
| Infraorder: | Cucujiformia |
| Family: | Coccinellidae |
| Subfamily: | Scymninae |
| Tribe: | Scymnini Mulsant, 1850 |
The Scymnini are a tribe of insects within the family Coccinellidae. This group includes many small species that are commonly known as dusky ladybugs.
The adult beetles of Scymnini are small, typically one or two millimeters long. Their body is hemispherically domed and is almost always covered with dense hair. Only a few species have a smooth and glossy back surface. Many species can be identified by their characteristic pattern and their size, however examination under a microscope is usually needed.
The Scymnini like the Chilocorini show their head well below the prothorax (pronotum). Their very short probes are built differently and have a reduced number of members. The Chilocorini differ from the Scymnini by their greatly expanded endplates ( clypeus ).
The larvae of Scymnini secrete a white, waxy substance, which their body is covered with. Exceptions are only seen in the species of the genus Stethorus who have no such guard formations. On the other hand, there are wax coatings also in the larvae of other tribes of ladybugs, z. B. in Coccidulini and Chilocorini. [1] The larvae have also been known for forming small congregations of their own species, leaving a white smudge on the surface they are on.
The species of the tribe Scymnini are distributed worldwide. They feed on spider mites , scale insects, Aledyrodoid moths and aphids. The beetles lay their eggs on leaves, which are infested with the lice or mites. These are not only predatory as adults but also as larvae.
The Scymnini were nomenclatured for a long time under the name Scymninae as one of numerous subfamilies of ladybugs. In 2007 was Adam Ślipiński proposed a new system, [2] which contains only two subfamilies. Under that system, the Scymnini belong to the subfamily as Tribe Coccinellinae. [3] The internal and external classification of Scymnini within this new subfamily needs to be investigated in more detail. Preliminary molecular studies have shown that the family is probably paraphyletic.
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 70 species distributed in five genera. It was indicated Cucujus species are scavengers, only feeding on pupae and larvae of other insects and on other subcortical beetles such as their own. Since the Cucujidae prey on larvae of potentially tree damaging beetles that spread fungal diseases, they are considered to be beneficial to the health of living trees.
Staphylinoidea is a superfamily of beetles. It is a very large and diverse group with worldwide distribution.
Byrrhoidea is a superfamily of beetles belonging to Elateriformia that includes several families which are either aquatic or associated with a semi-aquatic habitat. Other than the superfamily Hydrophiloidea, most of the remaining Polyphagan beetles which are aquatic are in this superfamily.
The family Pythidae is a small group of tenebrionoid beetles with no vernacular common name, though recent authors have coined the name dead log bark beetles. There are seven genera, which are largely native to the mid-high latitude regions of the Northern Hemisphere and Australia, with one genus also present in the tropical Americas. The larvae are generally found with decaying vegetation and wood on which they feed, while adults are not associated with the larvae and are generally caught using malaise traps and light traps.
Corylophidae is a family of minute hooded beetles, sometimes called minute fungus beetles, in the superfamily Coccinelloidea. There are about 18 genera and at least 120 described species in Corylophidae. They feed on microfungi such as molds, and are often found associated with bark, as well as in leaf litter and other decaying vegetation. In older literature, the family name was often given as Orthoperidae.
Histeroidea is a superfamily of beetles in the infraorder Staphyliniformia.
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. They are found on every continent except Antarctica.
Bothrideridae is a family of beetles in the superfamily Coccinelloidea. They are known commonly as the cocoon-forming beetles or dry bark beetles. They occur worldwide with most native to the Old World tropics. In older literature, the family was often included in the family Colydiidae, but is now considered unrelated.
Cavognathidae is a family of beetles, in the superfamily Cucujoidea. It contains a single genus, Taphropiestes with around a dozen species known from South America, Australia and New Zealand. In Australian and New Zealand species adults and larvae have been found living in bird nests, but their ecology is unclear, but they are possibly scavengers.
Silvanidae, "silvan flat bark beetles", is a family of beetles in the superfamily Cucujoidea, consisting of 68 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.
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.
Protocucujidae is a family of beetles, in the superfamily Cucujoidea. It has a single known genus, Ericmodes. Species of Ericmodes are native to southern South America and Eastern Australia. Little is known of their biology, though adults and larvae probably live on vegetation, with adults having also been found in leaf litter and in flight.
Stenotrachelidae, commonly called false longhorn beetles is a family of beetles in the superfamily Tenebrionoidea. They are native to the Holarctic region. The larvae feed on heavily decomposed wood, while the adults are likely short lived and probably feed on pollen.
Trachelostenus is a genus of darkling beetles in the family Tenebrionidae. It is native to the Valdivian forests of Chile, and has at least two species, T. inaequalis (Solier) and T. fascicularis (Philipp). It was historically considered the only member of the family Trachelostenidae, but a 2015 study sunk the genus into the tenebrionid subfamily Tenebrioninae.
The Epilachninae are a subfamily of the family of lady beetles, the Coccinellidae, in the order Coleoptera. Superficially, they look much like other ladybirds in the larger subfamily Coccinellinae, but they differ importantly in their biology, in that the members of the subfamily are largely or completely leaf-feeding herbivores rather than being predators. Accordingly, several members of the subfamily are crop pests, and sometimes cause locally serious crop losses.
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.
Agapytho is the only genus of beetles in the family Agapythidae. The genus contains a single species, Agapytho foveicollis, which is endemic to New Zealand. Larvae and adults are found on sooty mold growing on Nothofagus trees. Gut contents indicate that at least adult Agapytho consume the sooty mould as part of their diet.
Myrabolia is the only genus in the beetle family Myraboliidae in the superfamily Cucujoidea. It has about 13 species, found in Australia. Adults and possibly larvae live under the bark of Eucalyptus trees.
Tasmosalpingus is the only genus in the beetle family Tasmosalpingidae. There are two species in Tasmosalpingus, found in Australia in Tasmania, Victoria and New South Wales. Adults have been collected using malaise traps, while a possible larval specimen was found under the bark of the podocarp Phyllocladus aspleniifolius. Gut contents indicate that they are mycophagous, feeding on fungal hyphae.
Trachelostenini is a tribe of darkling beetles in the family Tenebrionidae. There are at least three genera in Trachelostenini. It was historically ranked as the family Trachelostenidae, but a 2015 study sunk the family into the tenebrionid subfamily Tenebrioninae.