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Syrphidae: Toxomerini - US/Canada(in development)

Authors: Even Dankowicz

Last updated: May 2019

Help identify observations on iNaturalist:

https://www.inaturalist.org/observations/identify?taxon_id=520010&place_id=6712,1

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Toxomerini: Toxomerus

		Scutellum	T3-4 lateral markings	T3-4 medial stripes	T3-4 posterior band	hind femur	other unique features
T. marginatus	widespread	Either diffuse or dark with distinct lighter margin	Expressed along lateral margin all the way to anterior margin or faded	2 narrow stripes	moderately thick, or faded	yellow	abdomen with yellow lateral margin
T. politus	widespread	Diffuse	Expressed along lateral margin halfway to anterior margin	2 narrow stripes widen into T-shape anteriorly	relatively thick, posteriorly bluish	yellow
T. corbis	VA to FL	Diffuse	absent	2 indistinct narrow spots/stripes	relatively narrow, bluish	yellow
T. jussiaeae	Eastern USA	Diffuse	indistinct	2 narrow stripes	moderately thick	yellow	unlike politus, corbis, etc, T2 medially divided by black stripe
T. mutuus	TX	Diffuse	slightly widening laterally	2 narrow stripes	moderately thick, posteriorly bluish	yellow	narrow abdomen compared to most other spp
T. teliger	AZ	dark with distinct lighter margin	Expressed laterally mostly to anterior margin	black medial stripe/stripes - thick diamond-like	moderately thick, posteriorly bluish	apical half brown-black (cf. T tibicen)
T. verticalis	FL	dark with distinct lighter margin	indistinct	1 medial stripe	thick, posteriorly bluish	with black ring or apical dark?
T. boscii	Eastern USA	dark with distinct lighter margin	Expressed sub-laterally, nearly to anterior margin	2 narrow stripes	indistinct, very narrow	with black ring
T. floralis	TX, FL	dark with distinct lighter margin	Expressed along lateral margin mostly to anterior margin	2 narrow stripes	moderately thick or faded	with black ring
T. dispar	TX, FL	dark with distinct lighter margin	Expressed along lateral margin mostly to anterior margin	1-2 medial black stripes	moderately thick or faded	with black ring	yellow stripe on side of scutum only extends to wing base
T. parvulus	GA, FL	dark with distinct lighter margin	Expressed along lateral margin connected to sub-lateral area	2 narrow stripes	very thick on T3, absent on T4	with black ring
T. arcifer	FL	dark with distinct lighter margin	Expressed along lateral margin connected to sub-lateral area	2 narrow stripes	often thick on T3, absent on T4	with black ring	sinuate yellow spots on tergite 2
T. geminatus	East of the rockies	dark with distinct lighter margin	Expressed sub-laterally, often halfway to anterior margin	2 narrow stripes	relatively thick	with black ring
T. occidentalis	West of rockies, to TX	dark with distinct lighter margin	Expressed sub-laterally, relatively indistinct	2 narrow stripes	relatively thick	with black ring

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Toxomerus boscii

VA, © Judy Gallagher, iNaturalist / CC BY

Toxomerus marginatus

OK, © Greg Silva, iNaturalist / CC BY-NC

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Toxomerus geminatus

ON, © Reiner Jakubowski, iNaturalist / CC BY-NC

Toxomerus occidentalis

CA, © mjbolte, iNaturalist / CC BY-NC

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Toxomerus verticalis

Toxomerus politus

Argentina, © RAP, iNaturalist / CC BY-NC

FL, © Judy Gallagher, iNaturalist / CC BY

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Other species

Several other species could not be illustrated but are included in the initial table:

T. floralis
T. dispar
T. arcifer
T. corbis
T. parvulus
T. mutuus
T. teliger

Toxomerus jussiaeae

OK, © Emily Hjalmarson, iNaturalist / CC BY-NC

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Hawaiian species

Toxomerus marginatus

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References

Sources for this entire project include:

BugGuide.net
iNaturalist.org
Steve Marshall - Flies: The Natural History and Diversity of Diptera
Diptera.dk / Systema Dipterorum
Nearctic Manual of Diptera

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References

Other sources consulted for this specific document include:

Miranda, Young, Locke, Marshall, Skevington, Thompson, 2013. Key to the Genera of Nearctic Syrphidae. Canadian Journal of Arthropod Identification. 23. http://cjai.biologicalsurvey.ca/mylmst_23/mylmst_23.html
http://www3.ucol.mx/linbos/list_syrp_huoa.htm - Los insectos del Bosque Seco
Journal posts by Caleb Scholtens: https://www.inaturalist.org/posts/14985-identifying-toxomerus-hoverflies and https://www.inaturalist.org/journal/upupa-epops/16742-random-toxomerus-stuff
Photos of Toxomerus corbis (weirdly different from type in Hull 1943): https://mczbase.mcz.harvard.edu/name/Mesogramma%20planiventris and http://scan-bugs.org/portal/collections/individual/index.php?occid=22824854
BOLD specimen photos: http://beta.boldsystems.org/index.php/Taxbrowser_Taxonpage?taxid=388624

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References

Other sources consulted for this specific document include:

Australian-Oceanian Diptera Catalog
Hull, 1943. The genus Mesogramma. Entomologica Americana. 23: 1-41.
Fluke, 1953. New Syrphidae from North America (Diptera). Journal of the Kansas Entomological Society. 26(4): 125-129.
Thompson, 1981. Flower Flies of the West Indies.

For T. teliger, see: Metz, Thompson, 2001. A revision of the larger species of Toxomerus (Diptera: Syrphidae) with description of a new species. Studia dipterologica 8