Helophilus | |
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Helophilus pendulus | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Arthropoda |
Class: | Insecta |
Order: | Diptera |
Family: | Syrphidae |
Subfamily: | Eristalinae |
Tribe: | Eristalini |
Subtribe: | Helophilina |
Genus: | Helophilus Meigen, 1822 [1] |
Helophilus are a diverse genus of moderate to large hoverflies, that appear somewhat bee-like. This genus comprises two subgenera: Helophilus and Pilinasica. [2] Larvae filter-feed in organic rich water. All Helophilus adults have a distinctive lengthwise striped thorax and a transverse striped abdomen. [3] [4]
The species in genus Helophilus are large yellow-black hoverflies ranging in length from 9 to 16.5mm. They are very fast flies with big eyes. Most of these flies have yellow stripes on their scutum, large yellow-orange markings on their abdomen, and an elongate pterostigma on the wing. [5] Some special species are blue metallic ( Helophilus hochstetteri )or black and white( Helophilus cingulatus ).It looks like a bee as an adult.
Diet
Adults feed on pollen and nectar. They get protein from the pollen and energy from the nectar. Females often need to eat pollen before their eggs will develops. Larvae feed on the micro-organisms responsible for the decay in ponds and ditches. [6]
Foraging behavior
The flight period of Helophilus is mostly summer. In Europe, flight periods commence as early as March and conclude as late as October. [7] Helophilus rarely hovered, seeming to fly without hesitation from one flower to another. [8] When Helophilus was alarmed, they will change their flight to zig-zag flight which makes them look like bees. [9] They make large amplitude dorsoventral movements of their abdomen while they are foraging on flowers. [8]
Pollination
Most specices are not specialized. Some species have flower color requirements, such as Helophilus pendulus tended to prefer white and yellow flowers. [7]
Adults feed on pollen and nectar in flowers. They have more pollen-gathering hairs on the body so that pollen is collected while they sip nectar. This pollen is then groomed from the body by the legs and transferred to the mouth. [10] This genus is certainly a pollinator. They are not restricted to a limited home range and may carry pollen over longer distances than bees while foraging, [11] and over considerably longer distances during migration. [12] Migratory species may also be present in very high densities, which may make up for potentially lower pollinator efficiency. [13] Migratory pollinators may be particularly important for geographically isolated plant populations. [14]
Some species of genus Helophilus such as H.groenlandicus can lead to some self-pollination in P. laurentiana. [15]
Migration
There is a few species that migrate, such as H. trivittatus [16] and H. affinis . The migrated species are capable of crossing considerable stretches of ocean. [4]
The adults are short-lived and survived for a few days to a few weeks. The adults lay their eggs in water rich in nutrients and organic matter. The eggs hatch after a short period which is highly dependent upon temperature. [4] The larvae live in the mud at the bottom and have organs at the end of their bodies to help them breathe. The posterior end of the body is highly elongated into a telescopic siphon, which is extened to the surface and adjusted in length according to the depth of the water or mud. The larvae are called rat-tail maggots. [10] The larvae are similar to those of genus Eristalis, Eristalinus, Anasimyia, Lejops and Parhelophilus. [17] When fully grown, the rat-tailed maggots leave the water and make a small oval chamber in damp earth nearby. [10] Its skin hardens and protects the pupae inside. [10]
The Helophilus mainly distribute in Europe, North America, Asia and New Zealand. There is a few obversations in Africa and South America. [18]
The climate could influence the distribution. Helophilus tends to the warm and wet place. And the adults prefer the sunny places to sunbathe, such as the fresh leaves of Cow Parsley in Europe. [4]
The helophilus in New Zealand comprises 12 species, of which five species (H. antipodus, H.hochstetteri, H. seelandicus, H. cingulatus, H. campbelli ) are endemic. [19] The endemic New Zealand species are under the oldest genus-group name (Pilinascia), as a subgenus of Helophilus. [2] These species are the pollinators of the endemic plants. It has a significant impact on the reproduction of endemic endangered plants. H. antipodus is a pollinator of the endemic orchid Dendrobium cunninghamii on the main island. [20] H.hochstetteri serves as synergistic pollinators alongside honey bees for kiwifruit. [21]
Distribution
Helophilus distribute all around New Zealand, include islands.
A pollinator is an animal that moves pollen from the male anther of a flower to the female stigma of a flower. This helps to bring about fertilization of the ovules in the flower by the male gametes from the pollen grains.
Hoverflies, also called flower flies or syrphids, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while the larvae (maggots) eat a wide range of foods. In some species, the larvae are saprotrophs specifically Detritivores eating decaying plant and animal matter in the soil or in ponds and streams. In other species, the larvae are insectivores, preying on aphids, thrips, and other plant-sucking insects.
Eristalis is a large genus of hoverflies, family Syrphidae, in the order Diptera. Several species are known as drone flies because they bear a resemblance to honeybee drones.
Eristalis tenax, the common drone fly, is a common, migratory, cosmopolitan species of hover fly. It is the most widely distributed syrphid species in the world, and is known from all regions except the Antarctic. It has been introduced into North America and is widely established. It can be found in gardens and fields in Europe and Australia. It has also been found in the Himalayas.
Rhingia campestris is a species of hoverfly, 7–11 millimetres (0.3–0.4 in) long, with a wingspan of 12–18 mm (0.5–0.7 in). It is common across the Palearctic from March until November. It has a broad orange abdomen with a black line along the sides, and has the distinctive long snout of all Rhingia species. Rhingia campestris is the main pollinator for many plant species and due to its long snout it can forage on tubulous flowers. Larvae are associated with cow dung. Adults males feed on nectar, while adult females feed on protein rich pollen, reflecting the cost of developing eggs.
Melangyna viridiceps is an Australian hoverfly, known as the common hover fly.
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.
Allograpta is a very large and diverse genus of hoverflies present throughout the world except most of the palearctic region. The adults are brightly coloured flower pollinators and most larvae have a predatory feeding mode involving soft-bodied sternorrhynchans. Certain species have diverged from this and their larvae have been found to be leaf-miners, stem-borers or pollen-feeders.
Toxomerus is a very large genus of hoverflies. They are found in many parts of North and South America. Most larvae are predators on soft bodied insects, though a few species have been shown to feed on pollen. Adults feed on the pollen of a wide range of flowers.
Helophilus groenlandicus, the Black-margined Marsh Fly, is a common species of syrphid fly. Hoverflies can remain nearly motionless in flight. The adults are also known as flower flies for they are commonly found on flowers, from which they get both energy-giving nectar and protein-rich pollen. Though common the larvae of this species like many other Helophilus are not known but the larvae of other species in this genus are associated with wet decaying organic material, particularly accumulations of decaying vegetation in ponds and mud and are a so called rat-tailed type.
Sericomyia chrysotoxoides ,, the Oblique-banded Pond Fly , is a common species of syrphid fly observed across the eastern half of North America and in the Rocky Mountains. Syrphid flies are also known as Hover Flies or Flower Flies because the adults are frequently found hovering around flowers from which they feed on nectar and pollen. Adults are 9.6–1,315.3 mm (0.38–51.78 in) long, black with yellow bands, less prominent in the male. The larvae of this genus are known as rat tailed maggots for the long posterior breathing tube.
Helophilus seelandicus, commonly known as the three-lined hoverfly, is a hoverfly endemic to New Zealand. The common name corresponds to the three black lines behind the insect's head.
Melangyna novaezelandiae is a hoverfly endemic to New Zealand. It is a generalized pollinator of a large range of plants that are both native and exotic to the New Zealand flora. M. novaezelandiae is widespread throughout New Zealand, including in agricultural environments. The larvae of this species feeds on other arthropods and may have uses as a biocontrol agent.
The pollinators in New Zealand include bees, tūī birds, and syrphid flies, which all contribute to the ecology of New Zealand.
Melanostoma fasciatum is a species of hoverfly found in New Zealand, where it is common in agricultural fields and gardens. Locally dense populations of this hoverfly species might effectively reduce pest infestation. Hence, they are perhaps an effective natural and non-toxic bioagent that may control and reduce aphid and small caterpillar populations.
Spilomyia longicornis is a species of syrphid fly, also known as a flower fly or hoverfly, in the family Syrphidae. Although the appearance of S. longicornis is remarkably similar to a vespid wasp, it is a fly and cannot sting. It occurs in North America, east of the Rocky Mountains.
Sericomyia transversa , the Yellow-spotted Pond Fly , is an uncommon species of syrphid fly observed in northeastern North America.. Hoverflies can remain nearly motionless in flight. The adults are also known as flower flies for they are commonly found on flowers, from which they get both energy-giving nectar and protein-rich pollen. The larvae of this genus are known as rat tailed maggots for the long posterior breathing tube.
Sericomyia lata , the White-spotted Pond Fly , is a common species of syrphid fly observed across North America, concentrated in the east. Syrphid flies are also known as Hover Flies or Flower Flies because the adults are frequently found hovering around flowers from which they feed on nectar and pollen. Adults are 11.6–15.2 mm (0.46–0.60 in) long and black with large white abdominal spots. The larvae of this genus are known as rat tailed maggots for the long posterior breathing tube.
Helophilus antipodus is a endemic species of hoverfly observed throughout New Zealand. It belongs to the genus Helophilus in the family Syrphidae. The adults are pollinators.