Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
 

Register · Log In
HomeGuideID RequestRecentFrassForumsDonateHelp
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Calendar
Upcoming Events

Photos of insects and people from the 2024 BugGuide gathering in Idaho July 24-27

Moth submissions from National Moth Week 2024

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

Photos of insects and people from the 2019 gathering in Louisiana, July 25-27

Photos of insects and people from the 2018 gathering in Virginia, July 27-29


Previous events
TaxonomyBrowseInfoImagesLinksBooksData
Home » Guide » Arthropods (Arthropoda) » Hexapods (Hexapoda) » Insects (Insecta) » Flies (Diptera) » "Acalyptratae" » Sphaeroceroidea » Lesser Dung Flies (Sphaeroceridae) » Limosininae » Opacifrons » Opacifrons maculifrons
Photo#233407
Fly - Opacifrons maculifrons
Copyright © 2008 John F. Carr

Fly - Opacifrons maculifrons
Cass Park, Ithaca, Tompkins County, New York, USA
October 11, 2008
Size: 4 mm (approx)
Among weeds and slime and sticks on the shore of Cayuga Lake. I think this kind of fly was walking on the water surface some of the time. This individual appears to be perched on something more solid.

With bonus mite at bottom right, or something that looks like a mite. I didn't notice it when I took the picture.
tag · login or register to post comments
Contributed by John F. Carr on 13 October, 2008 - 7:47pm
Last updated 14 October, 2008 - 9:10am

Opacifrons maculifrons (NY)
Easily recognised by the large, silvery spots on the top of the head. The size would be no more than 5 mm, though. The habitat you describe is typical for this species. New genus and species for Bugguide!
… Matthias Buck, 14 October, 2008 - 8:50am login or register to post comments

 
Size calculation
I made a mistake in size. I corrected 7mm to 4mm.

Here's an explanation of the calculation.

I had a Sigma 150mm macro lens with 1.4x teleconverter. The lens reported focus distance of 50 cm but that's approximate. If exact the magnification ratio would be 2:1 without teleconverter and 1.4:1 with teleconverter. In fact any ratio from 1.7:1 to 2.5:1 (without TC) will be reported the same; this lens isn't very precise in reporting distance.

This fly is 500 pixels long from from of head to tip of wings (not necessarily tip of abdomen). It's not quite parallel to the image plane, but close enough. So 500 pixels x 5 microns per pixel on D300 camera x 1.4 for magnification ratio = 3.5 mm. Given the precision of the distance report, size could be 3-5mm. It looked like the larger end of that range.
… John F. Carr, 14 October, 2008 - 9:09am login or register to post comments

Shore fly, I'd say
http://bugguide.net/node/view/9357/bgimage

Might be hydrellia.
… Ron Hemberger, 13 October, 2008 - 11:50pm login or register to post comments

Comment viewing options
Select your preferred way to display the comments and click 'Save settings' to activate your changes.

Disclaimer: Dedicated naturalists volunteer their time and resources here to provide this service. We strive to provide accurate information, but we are mostly just amateurs attempting to make sense of a diverse natural world. If you need expert professional advice, contact your local extension office.

Contributors own the copyright to and are solely responsible for contributed content.
Click the contributor's name for licensing and usage information.
Everything else copyright © 2003-2024 Iowa State University, unless otherwise noted.

Bugguide is hosted by:

Plant Pathology, Entomology and Microbiology at Iowa State University logo

Printer Friendly Version 		Terms of Use
Privacy Statement
Site Map
Contact