''Platycheirus amplus'' the Broadhand Sedgesitter is a rare
Holarctic
The Holarctic realm is a biogeographic realm that comprises the majority of habitats found throughout the continents in the Northern Hemisphere. It corresponds to the floristic Boreal Kingdom. It includes both the Nearctic zoogeographical reg ...
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of
hoverfly
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 l ...
found in wetlands, fens, moorland streams and bogs.
[ ]
Description
External images and mapFor terminology se
Speight key to genera and glossaryo
Glossary of morphological terminology br>

See references for
determination
Determination is a positive emotional feeling that promotes persevering towards a difficult goal in spite of obstacles. Determination occurs prior to goal attainment and serves to motivate behavior that will help achieve one's goal.
Empirical ...
.
:;Note: See "general anatomy" below for diagrams of Syrphid (not this species) parts
:;Head: The face is moderately projecting ventrally, with the anterior oral margin produced forward but not reaching the level of the tubercle. It is densely covered with yellow pollen and features a shining tubercle. (Figure 1)
:;Legs: The fore tibia is broadened from the base and then more strongly broadened on the apical fifth. The first fore tarsomere is strongly flattened, about twice as long as wide, and features a weak dorsal keel apically. The second fore tarsomere is flattened, approximately as long as wide, and half the width of the first. The remaining fore tarsomeres are unmodified.(see figure 2 top) The mid-femur has a shallow anterior excavation located about three-quarters of its length, bordered by short, strong black setulae. The mid-tibia is slightly swollen near the base and has a tuft of dense, wavy black pile that can be up to three times the tibial diameter on the subbasal swelling.(Figure 2 middle) The hind leg, except for the narrow apex of the femur and the base of the tibia, is dark. The first hind tarsomere is swollen basally and tapers uniformly to a narrow apex.(Figure 2 bottom)
:;Thorax: The thorax is sparsely covered with yellow or grey pollen. The scutellar hairs are approximately as long as the arista. The scutal hair is mostly white, with some black hairs near the margins.
:;Wings: The wing is usually slightly brown-tinted, with very small bare areas located at the bases of cells c and bm. (Figure 3)
:;Abdomen: The abdomen has yellow spots on tergites 2 to 5. Segment 2 features small, variable-shaped spots located at mid-length. Segments 3 and 4 have large, rectangular spots that touch the front margin. Segment 5 contains small, triangular spots that also touch the front margin.
image:Syrphid leg diagram.png , Legs
image:Head diagram.png, Head
image: Platycheirus wing diagram.jpg, Wing
image: Syrphid body1.png, Body
Distribution
Palearctic
The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa.
Th ...
: Britain, Ireland, Sweden, Denmark, the Netherlands and Belgium.
Nearctic
The Nearctic realm is one of the eight biogeographic realms constituting the Earth's land surface.
The Nearctic realm covers most of North America, including Greenland, Central Florida, and the highlands of Mexico. The parts of North America ...
: Alaska south to California.
[Peck, L.V. (1988). "Syrphidae". In: Soos, A. & Papp, L. (eds.). ''Catalogue of Palaearctic Diptera'' 8: 11-230. Akad. Kiado, Budapest.
]
Biology
Habitat: fen and poor fen, flushes and brooks in moor and bog.
It flies June to July. ''Playcheirus'' larvae feed on
aphid
Aphids are small sap-sucking insects in the Taxonomic rank, family Aphididae. Common names include greenfly and blackfly, although individuals within a species can vary widely in color. The group includes the fluffy white Eriosomatinae, woolly ...
s on various low-growing plants and bushes.
A19
References
{{DEFAULTSORT:Platycheirus Amplus
Diptera of Europe
Hoverflies of Europe
Hoverflies of North America
Syrphinae
Insects described in 1927
category: Taxa named by Charles Howard Curran
Fauna of the Rocky Mountains