Poecilochirus | |
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Poecilochirus carabi | |
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Genus: | Poecilochirus G. & R. Canestrini, 1882 |
Type species | |
Poecilochirus carabi G. & R. Canestrini, 1882 |
Poecilochirus is a Holarctic genus of mites in the family Parasitidae. [1] They are relatively large (ca. 0.5-1mm [2] ) and often found on rotting corpses, where they are transported by beetles. [3] [4] Deuteronymphs are characterized by two orange dorsal shields and in many species a transverse band on the sternal shield. The juvenile development consists of a larval stage (three pairs of legs), protonymph, and deuteronymph, but no tritonymph. Females are smaller than males. Males guard female deuteronymphs shortly before these mate, and pairs mate venter-to-venter. [5]
Reportedly, some nematodes in the family Allantonematidae are parasites of mites in this genus. [6] Although some species from this genus have been described and sampled on previous real forensic cases or successional studies on carcasses, their usefulness as a forensic marker in forensic entomology has been recently appreciated. [7]
At least eight species of the genus are carried from one food source to another by beetles of multiple genera in the family Silphidae, most notably burying beetles. The mite deutonymphs sit on the adult beetles, typically between the coxae or under the elytrons. The beetles breed on carrion, which some species bury. Once arrived on carrion, the mites leave the beetles, feed on the carrion, and develop into adults. [8] The entire life cycle of the mites takes place on the carrion, and the young mites later leave again with the beetles. [4]
The probably best studied species are from the Poecilochirus carabi species complex that consists of at least two species (P. carabi and P. necrophori). [3] [4] [9] In Europe, the two mite species are specialized on two different species of burying beetles, Nicrophorus vespilloides and Nicrophorus vespillo . The mites can recognize their main host beetle species and can produce more offspring along their preferred host beetle. [4] [9] Similarly, two genetic lines of Poecilochirus carabi mites have been reported from North America, which specialize on different sets of Nicrophorus hosts in some populations. [10]
It is debated whether the mites harm the beetles or benefit them. Under certain conditions, the mites appear to protect the beetles' larvae or their food supply from fly larvae, [11] [12] but the presence of mites on beetle-tended carcasses also reduces male beetle life span and the number of beetle offspring. [13] [14] [9] [15] [8]
There is no recent treatment of the genus Poecilochirus. Identification keys mostly rely on the extent of a dark band across the sternal shield, the size of the dorsal shields, the doral chaetotaxy (mainly the length of the setae), and appendices of the fixed digit of the chelicerae. [2] The first description of all life stages was published by Neumann. [16]
Species | Synonyms | Habitat / Host species |
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Poecilochirus armatusTrägårdh, 1912 | ||
Poecilochirus austroasiaticusVitzhum, 1930 | P. nordi [2] | Nicrophorus and other Silphid beetles [17] [2] |
Poecilochirus belkahvensisRamaraju & Madanlar, 1998 | mushroom compost | |
Poecilochirus belovaeDavydova, 1975 | P. donatus [18] | |
Poecilochirus britannicusHyatt, 1986 | ||
Poecilochirus carabi G. Canestrini & R. Canestrini, 1882 | Gamasoides carabi, P. fucorum [2] | Nicrophorus vespilloides (main host [4] [9] ), other Nicrophorus & Silphid beetles [17] |
Poecilochirus coimbatorensis Vishnupriya & Mohanasundaram, 1988 | ||
Poecilochirus coleophorae Ramaraju & Mohanasundaram, 1997 | beetles: Rutelidae, Scarabaeidae | |
Poecilochirus davydovae Hyatt, 1980 | Nicrophorus and other Silphid beetles [2] [17] | |
Poecilochirus hyatti Ramaraju & Madanlar, 1998 | mushroom compost | |
Poecilochirus macgillavryi Oudemans, 1927 | ||
Poecilochirus monospinosus Wise, Hennessey & Axtell, 1988 | chicken manure | |
Poecilochirus mrciaki Masan, 1999 | Nicrophorus and other Silphid beetles [17] | |
Poecilochirus necrophori Vitzthum, 1930 [19] | Nicrophorus vespillo (main host [4] [9] ), other Nicrophorus & Silphid beetles [17] | |
Poecilochirus pilosula Banks, 1904 | Nicrophorus beetles [17] | |
Poecilochirus rutellae Ramaraju & Mohanasundaram, 1997 | beetles: Rutelidae, Scarabaeidae | |
Poecilochirus sexclavatus Skljar, 2002 | Nicrophorus and other beetles [17] | |
Poecilochirus simplisetae Ramaraju & Madanlar, 1998 | mushroom compost | |
Poecilochirus subterraneus Muller, 1859 | Nicrophorus and other Silphid beetles [2] [17] | |
Poecilochirus torbaliensis Ramaraju & Madanlar, 1998 | mushroom compost |
A study of the Poecilochirus carabi complex genetics [20] suggests that the species complex consists of many more than only two species (P. necrophori and P. carabi). The mites from Asia and America that would previously have been identified as P. carabi based on their morphology are from distinct genetic lineages. Data suggest that there may be 17 different P. carabi complex species that are not yet described. In addition, the mites that have been identified as P. subterraneus based on their morphology also likely belong to more than one species.
Forensic entomology is a field of forensic science that uses insects found on corpses to help solve criminal cases. This includes the study of insect types commonly associated with cadavers, their respective life cycles, their ecological presences in a given environment, as well as the changes in insect assemblage with the progression of decomposition. Insect succession patterns are identified based on the time a given species of insect spends in a given developmental stage, and how many generations have been produced since the insects introduction to a given food source. Insect development alongside environmental data such as temperature and vapor density, can be used to estimate the time since death, due to the fact that flying insects are attracted to a body immediately after death, determine any possible movement of the body after death, and the determination of antemortem trauma.. The identification of postmortem interval to aid in death investigations is the primary scope of this scientific field. However, forensic entomology is not limited to homicides, it has also been used in cases of neglect and abuse, in toxicology contexts to detect the presence of drugs, and in dry shelf food contamination incidents. Equally, insect assemblages present on a body, can be used to approximate a given location, as certain insects may be unique to certain areas. Therefore, forensic entomology can be divided into three subfields: urban, stored-product and medico-legal/medico-criminal entomology.
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. Members of Nicrophorinae are sometimes known as burying beetles or sexton beetles. The number of species is relatively small, at around two hundred. They are more diverse in the temperate region although a few tropical endemics are known. Both subfamilies feed on decaying organic matter such as dead animals. The subfamilies differ in which uses parental care and which types of carcasses they prefer. Silphidae are considered to be of importance to forensic entomologists because when they are found on a decaying body they are used to help estimate a post-mortem interval.
Burying beetles or sexton beetles, genus Nicrophorus, are the best-known members of the family Silphidae. Most of these beetles are black with red markings on the elytra (forewings). Burying beetles are true to their name—they bury the carcasses of small vertebrates such as birds and rodents as a food source for their larvae, this makes them carnivorous. They are unusual among insects in that both the male and female parents take care of the brood.
Mites are small arachnids. Mites span two large orders of arachnids, the Acariformes and the Parasitiformes, which were historically grouped together in the subclass Acari. However, most recent genetic analyses do not recover the two as each other's closest relative within Arachnida, rendering the group non-monophyletic. Most mites are tiny, less than 1 mm (0.04 in) in length, and have a simple, unsegmented body plan. The small size of most species makes them easily overlooked; some species live in water, many live in soil as decomposers, others live on plants, sometimes creating galls, while others are predators or parasites. This last type includes the commercially destructive Varroa parasite of honey bees, as well as scabies mites of humans. Most species are harmless to humans, but a few are associated with allergies or may transmit diseases.
Parasitiformes are a superorder of Arachnids, constituting one of the two major groups of mites, alongside Acariformes. Parasitiformes has, at times, been classified at the rank of order or suborder.
Nicrophorus vespilloides is a burying beetle described by Johann Friedrich Wilhelm Herbst in 1783. The beetles vary widely in size and can present with a range of anywhere from 12 mm to 20 mm in size. They have two conspicuous orange-yellow bands on the elytra. The color of the antennae are an important distinguishing feature, being totally black. The color of their orange and black markings is multifunctional, as they are conspicuous to avian predators. In general, they present a unique ecological niche, which is their evolution of aposematism, or the strategy they use to warn predators through their conspicuous signals. The wing cases of these beetles possess a squarish shape and are notably shorter in length than their abdomens, indicating a distinct physical characteristic of the species.
Nicrophorus tomentosus is a species of burying beetle that was described by Friedrich Weber in 1801. The beetle belongs to the family Silphidae which are carrion beetles. The beetles have sensitive antennae that contain olfactory organs. Thus, the beetle can locate dead animals (carcass), and then as the name suggests, can bury them. However, unlike other burying beetles, N. tomentosus does not completely bury these brood carcasses. They instead dig a shallow hole under the carcass and cover it with leaf litter. Recognition of these beetles can be distinguished by its black color with orange markings on the wing covers (elytra).
Nicrophorus nepalensis, commonly known as a burying beetle, is widespread across tropical and subtropical countries in Asia. It belongs to the order Coleoptera and the family Silphidae, and is part of the nepalensis species-group, which is the second largest species group within the genus Nicrophorus. N. nepalensis differs from some other beetles in that it exhibits biparental care. Its role as a decomposer is crucial in the energy cycle and energy transformation in the ecosystem.
Nicrophorus pustulatus, also known as the pustulated carrion beetle or blistered burying beetle, is a species of burying beetle that was described by Johann Karl Wilhelm Illiger in 1807. This species is native to North America. N. pustulatus exhibits unique habitat utilization and breeding behaviour relative to other members of the genus. This species may be the only described example of a true parasitoid targeting a vertebrate host.
Nicrophorus quadripunctatus is a species of burying beetle that predominates in East Asia. First described by German entomologist Ernst Kraatz in 1877, this beetle has since been the subject of much scientific inquiry—particularly concerning its parental care. Like other burying beetles, N. quadripunctatus inhabit small, vertebrate animal carcasses. This environment provides the beetles with the requisite nutrients for themselves and their offspring. To limit resource theft and predation, the carcass is buried underground. For additional protection, a single, dominant male-female pair guards the carcass cooperatively.
Nicrophorus orbicollis is a nearctic burying beetle first described by Thomas Say in 1825. It is a member of the genus Nicrophorus or sexton beetles, comprising the most common beetles in the family Silphidae. This species is a decomposer feeding on carcasses of small dead animals. N. orbicollis can be used for scientific research both medically and forensically.
The American carrion beetle is a North American beetle of the family Silphidae. It lays its eggs in, and its larvae consume, raw flesh and fungi. The larvae and adults also consume fly larvae and the larvae of other carrion beetles that compete for the same food sources as its larvae.
Parasitidae is a family of predatory mites in the order Mesostigmata that has worldwide distribution. They are the only family in the superfamily Parasitoidea. Relatively large for mites, their color is often yellowish to dark brown. The family as a whole preys on a wide variety of microarthropods and nematodes, with individual species usually having a narrower range of prey. The family contains two subfamilies, 29 genera, and around 400 species.
Histiostoma is a genus of mites in the family Histiostomatidae.
Ascidae is a family of mites in the order Mesostigmata.
Parasitellus is a genus of mites in the family Parasitidae which are obligatory parasites of bumblebees. These mites can be found clinging to the carapace, sometimes in large numbers. Mites in this genus hibernate in the deutonymphal stage. In the tritonymph stage they can actively transfer from bumblebee to bumblebee from flowers, where they can survive up to 24 hours. After they arrive in a bumblebee nest, they will moult into adults. Whilst it is not known what factors trigger the mite to molt, in laboratory conditions P. fucorum were found to moult after eating fresh pollen, although overall moulting success was low. They are kleptoparasitic or neutral to beneficial, depending on life stage; females and deutonymphs feed on provisioned pollen, while other stages are predators of small arthropods.
Phoresis or phoresy is a non-permanent, commensalistic interaction in which one organism attaches itself to another solely for the purpose of travel. Phoresis has been observed directly in ticks and mites since the 18th century, and indirectly in fossils 320 million years old. It is not restricted to arthropods or animals; plants with seeds that disperse by attaching themselves to animals are also considered to be phoretic.
Blattisociidae is a family of mites in the order Mesostigmata.
Melicharidae is a family of mites in the order Mesostigmata.
Uropodina is an infraorder of mites in the order Mesostigmata.