Heterostylum robustum | |
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Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Family: | Bombyliidae |
Tribe: | Bombyliini |
Genus: | Heterostylum |
Species: | H. robustum |
Binomial name | |
Heterostylum robustum (Osten Sacken, 1877) | |
Synonyms [1] | |
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Heterostylum robustum is a species of bee flies in the family Bombyliidae. [1] [2] [3] [4] It has a nearctic distribution, being found in Canada (specifically Alberta), Mexico, and the USA (mainly in the West). [5] It is a bomber fly, parasitizing bees and wasps by launching its eggs into their nests its ovipositor. [6] It is the principal parasite of the alkali bee Nomia melanderi, an important alfalfa pollinator across Washington, Oregon, Idaho, and Wyoming. [7] Other hosts of the fly include Nomia nevadensis bakeri, [6] [8] [9] Dieunomia triangulifera, [6] [10] Calliopsis anthidia, [6] [11] [12] Nomia scutellaris, [6] and Halictus rubicundus. [6]
The eggs of H. robustum are 1.2 mm long, 0.7 mm wide, oval-shaped, and tapered on each end. [6] They have a coating of mucus to which soil particles adhere. [7] In the laboratory, the eggs take between about 8 and 11 days to incubate. [6] Like ground bee eggs, they are laid by adults emerging in spring before the beginning of winter. [6]
The development of the larvae of H. robustum can be divided into four stages. [6] [ clarification needed ] First stage larvae are nearly-white planidiums, very active and about 1.6 mm long. [6] They have 3 pairs of thoracic bristles, one long pair of caudal bristles, and 8 pairs of smaller bristles on the head and neck. [6] They move by grabbing the surfaces with their mouth hooks, contacting the ground with their posterior pseudopods and pushing forward. [6] [ clarification needed ] After the first stage they very quickly pass through an inactive second stage [7] and spend a longer time in a soft, helpless third stage [7] until they reach the fourth stage, in which they begin parasitizing the host. [6] As of 1973 it was unknown what they eat in the first three stages before parasitization. [6]
When they begin parasitizing the host, they firmly press their mouths to the host larvae, attach themselves with the maxillae, and penetrate the host's flesh with their minute mouth hooks. [6] Disturbed fourth-stage larvae that have begun feeding will let go if disturbed, but will then immediately reattach themselves or find a new host if necessary; several larvae placed together cannibalize each other. [6] These larvae are much more active than many other parasitic larvae. [6] Larvae in the fourth stage feed for 3 or 4 days and grow to about twice their former size. [6] In some areas (in the Utah area, but not in Oregon) after consuming the first host the larvae will leave the burrow and burrow through the soil until it finds another prepupal bee to parasitize, of which it consumes about half. [6] [ needs update ]
H. robustum larvae overwinter underground as bee larvae do; they dig upwards, usually from about 5-10 inches below-ground up to 2-3 inches below-ground. [6] They then dig large, oval-shaped spaces in which to spend the winter. [6] Their burrowing is done by gyrating their abdomens (in the back) to pack dirt behind them, and then gyrating their anterior ends (in the front) to loosen dirt ahead and above them. [6]
Bee flies begin to emerge about 10 days earlier than bees do, in the spring, and their period overlaps with bees by several weeks. [6] They tunnel to the surface and then immediately break and struggle out of the pupal skin, [6] which usually remains stuck to the ground and can sometimes be used to identify the presence of the parasites. [7] They then crawl to a nearby object and wait for about 10 minutes for their wings to dry. [6] During this period they are particularly vulnerable to predators, including many birds. [7] Once they are able to fly, the adults seek nectar and mate before beginning to lay eggs about two days later. [6] [7] Unlike some other bee flies, H. robustum flies do not touch the ground while they do this. [7]
Adults have unclouded wings, a tan thorax, and a gray and buff pattern on the abdomen, as well as a long proboscis. [7] Older flies lose the majority of the hair on their abdomen and become uniformly dark gray. [7] Males and females are similar except that males are holoptic and females are dichoptic. [7]
H. robustum is the principal parasite of the alkali bee Nomia melanderi, an important alfalfa pollinator (as of 1960) across Washington, Oregon, Idaho, and Wyoming, and can destroy large percentages of its larvae. [7] The percentage destroyed varies by region from over 90% in Cache Valley, Utah to less than 5% in some areas near Wapato, Washington, but in general is often between 20% and 40% in many areas. [7] In some areas formerly abundant with alkali bees, populations have been reduced to entirely insignificant levels by the parasite. [7]
At least two factors contribute to N. melanderi's ability to survive despite the high parasitism: every year some bees nest alone instead of in groups, and some bees always nest and lay eggs late, or even in a small "second generation" of bees which occurs in late August. [7]
Heterostylum robustum is found in Canada (Alberta), Mexico (Baja California Norte and Sur, Coahuila de Zaragoza, Guerrero, Morelos, Nuevo León, Puebla, Sinaloa, Sonora, Tamaulipas), and the USA (Arizona, California, Colorado, Georgia, Idaho, Kansas, Nevada, New Mexico, Oklahoma, Oregon, Texas, Utah). [5]
The Bombyliidae are a family of flies, commonly known as bee flies. Some are colloquially known as bomber flies. Adults generally feed on nectar and pollen, some being important pollinators. Larvae are mostly parasitoids of other insects.
Halictidae is the second-largest family of bees with nearly 4,500 species. They are commonly called sweat bees, as they are often attracted to perspiration. Halictid species are an extremely diverse group that can vary greatly in appearance. These bees occur all over the world and are found on every continent except Antarctica. Usually dark-colored and often metallic, halictids are found in various sizes, colors and patterns. Several species are all or partly green and a few are red, purple, or blue. A number of them have yellow markings, especially the males, which commonly have yellow faces, a pattern widespread among the various families of bees. The family is one of many with short tongues and is best distinguished by the arcuate basal vein found on the wing. Females in this family tend to be larger than the males. They are the group for which the term 'eusocial' was first coined by entomologist, Suzanne Batra.
Botflies, also known as warble flies, heel flies, and gadflies, are a family of flies known as the Oestridae. Their larvae are internal parasites of mammals, some species growing in the host's flesh and others within the gut. Dermatobia hominis is the only species of botfly known to parasitize humans routinely, though other species of flies cause myiasis in humans.
The apple maggot, also known as the railroad worm, is a species of fruit fly, and a pest of several types of fruits, especially apples. This species evolved about 150 years ago through a sympatric shift from the native host hawthorn to the domesticated apple species Malus domestica in the northeastern United States. This fly is believed to have been accidentally spread to the western United States from the endemic eastern United States region through contaminated apples at multiple points throughout the 20th century. The apple maggot uses Batesian mimicry as a method of defense, with coloration resembling that of the forelegs and pedipalps of a jumping spider.
The Phoridae are a family of small, hump-backed flies resembling fruit flies. Phorid flies can often be identified by their escape habit of running rapidly across a surface rather than taking to the wing. This behaviour is a source of one of their alternate names, scuttle fly. Another vernacular name, coffin fly, refers to Conicera tibialis. About 4,000 species are known in 230 genera. The most well-known species is cosmopolitan Megaselia scalaris. At 0.4 mm in length, the world's smallest fly is the phorid Euryplatea nanaknihali.
The Conopidae, also known as the thick-headed flies, are a family of flies within the Brachycera suborder of Diptera, and the sole member of the superfamily Conopoidea. Flies of the family Conopidae are distributed worldwide in all the biogeographic realms except for the poles and many of the Pacific islands. About 800 species in 47 genera are described worldwide, about 70 of which are found in North America. The majority of conopids are black and yellow, or black and white, and often strikingly resemble wasps, bees, or flies of the family Syrphidae, themselves notable bee mimics. A conopid is most frequently found at flowers, feeding on nectar with its proboscis, which is often long.
Poecilanthrax willistoni, Williston's bee fly or sand dune bee fly, is a member of the Bombyliidae insect family. This family includes the bee flies, true flies that have developed Batesian mimicry characteristics to avoid predators. That is, they look like bees because that helps them avoid bee-wary predators, but they lack stingers.
The Asilidae are the robber fly family, also called assassin flies. They are powerfully built, bristly flies with a short, stout proboscis enclosing the sharp, sucking hypopharynx. The name "robber flies" reflects their expert predatory habits; they feed mainly or exclusively on other insects and, as a rule, they wait in ambush and catch their prey in flight.
A planidium is a specialized form of insect larva seen in the first-instar of a few families of insects that have parasitoidal ways of life. They are usually flattened, highly sclerotized (hardened), and quite mobile. The function of the planidial stage is to find a host on which the later larval instars may feed, generally until the insect pupates.
Philanthus gibbosus, the hump-backed beewolf, is a species of bee-hunting wasp and is the most common and widespread member of the genus in North America. P. gibbosus is of the order Hymenoptera and the genus Philanthus. It is native to the Midwestern United States and the western Appalachians. P. gibbosus are often observed to visit flowers and other plants in search of insect prey to feed their young. The prey that P. gibbosus catches is then coated in a layer of pollen and fed to the young wasps.
Bombylius major is a parasitic bee mimic fly. B. major is the most common type of fly within the Bombylius genus. The fly derives its name from its close resemblance to bumblebees and are often mistaken for them.
Heterostylum is a genus of flies belonging to the family Bombyliidae (bee-flies). There are 14 described species, distributed throughout the Americas. These are robust and very hairy flies with a body length of 10–15 mm. They can be distinguished from similar genera by an indentation in the hind margin of the eye and unique wing venation.
Exoprosopa is a large cosmopolitan genus of flies belonging to the family Bombyliidae (bee-flies), with over 325 described species. The genus parasitizes a wide range of insects, including locust and larvae of wasps.
The alkali bee, Nomia melanderi, is a ground-nesting bee native to deserts and semi-arid desert basins of the western United States. It was described by Theodore Dru Alison Cockerell in 1906. While solitary, these bees nest near each other and can form extremely dense aggregations in areas with favorable conditions.
Nomia is a genus of sweat bees in the family Halictidae. Many species have opalescent bands on the metasoma. Nomia species are moderate-sized bees that nest in the ground. Most species nest solitarily, but some species also nest communally where females share a nest but where there are no queen or worker castes. Nomia species are found Africa, tropical Asia, Australia, and in North America. There are about 130 species world wide.
Bombylius canescens, commonly known as the western bee-fly, is a species of bee-fly belonging to the family Bombyliidae.
The tiger bee fly, Xenox tigrinus, is an insect of the family Bombyliidae found in the eastern United States and southern Ontario. It formerly went by the name Anthrax tigrinus. The distinctive wing pattern may resemble tiger stripes, giving the tiger bee fly its name. Like other members of the bee fly family, the tiger bee fly parasitizes the larvae of other insects.
Dieunomia triangulifera is a species of sweat bee in the family Halictidae. It is found in the central United States from central Illinois and Minnesota westward to Utah and southern New Mexico. Adult Dieunomia triangulifera closely resemble Dieunomia nevadensis, specifically Dieunomia nevadensis arizonensis.
Dieunomia nevadensis, the Nevada nomia, is a species of sweat bee in the family Halictidae. It is found in Central America and North America. It was first described by Ezra Cresson in 1874.
Exorista mella is a tachinid fly of the genus Ezorista within the family Tachinidae of the order Diptera. They are typically found in the United States and Canada. Within the U.S in the state of Arizona they have been found in both mountainous and agricultural regions. E. mella is a parasitoid fly, a polyphagous generalist which parasitizes a variety of hosts.
Synonyms: Nomia nevadensis
Synonyms: Nomia triangulifera