Tag Archives: fly

Ento. 101: Wing Structure and Venation

"Conehead wings pinned"

The saga continues: Entomology 101: Wing Structure and Wing Venation.

In the last section I introduced insect wings and will now move on to look at wing structure and venation. This post will confine itself to the essentials, with a more detailed look at variations in wing structure when I cover the insect orders in the chapter on diversity.

The wings connect to the thorax at three points, with various forms of axillae, which are stiff plates (sclerites) of cuticle that are activated by muscle movements in the thorax. Wings consist of two layers of cuticular membrane which sandwich a framework of veins through which hemolymph flows. The veins are also sclerotized and provide a strengthening structure to the wing. Other features of the wings include fold lines and lines of flexion. In some orders, the fore and hind wings move together as one when in flight, facilitated by various linking mechanisms.

Wing venation and the lines of folding and flexion all contribute to patterns that can assist in identification. The lines of venation have been ‘mapped’ with a common terminology called the Comstock-Needham system, which recognises the homology of wing veins across the insect orders. The Comstock–Needham system was developed by  John Comstock and George Needham in 1898,  and today it is variations of that system that are mostly used by entomologists. The Evolution of Insects goes with the Wootton variation (1979) which I follow below, while others may favour the Kukalova´-Peck variation. Continue reading »

Posted in Diptera, Entomology, Entomology 101, Insect, invertebrates, Science Also tagged , , , , , , , , , |

You’re Not

"Tachinid Fly, Dinosaur Provincial Park, Alberta."

Why not?

(Photographed on a sign at a in-situ dinosaur fossil display, Dinosaur Provincial Park, Alberta.)

Posted in Alberta, Diptera, Insect, macro, Provincial Park, Summer, Tachinidae, White Studio Also tagged |

Conopid Capture Capture

 

Conopid Fly with 'Prey'

Deep in the foliage at the back of the garden border I glimpsed a distorted pattern on one of the leaves. Looking closer I saw that it was a Conopid fly (probably Physocephala furcillata) with another captured Conopid. Otherwise known as Thick-headed flies, this particular species is a known parasite of solitary bees. I don’t know whether this was an attempt at parasitism (note extended ovipositor) or a territorial battle, but when my flash bumped the leaves, both flew off. One sped out of the garden and the other resumed its post near the flowers.

Conopid on Duty

From Wikipedia:

The larvae of all conopids are internal parasites, most of aculeate (stinging) Hymenoptera. Adult females aggressively intercept and deposit eggs on their hosts in-flight, and the female’s abdomen is modified to form what amounts to a “can opener” to pry open the segments of the host’s abdomen as the egg is inserted.

Posted in Diptera, garden, Parasitism, Summer, Web LInk Also tagged , , , , , |

Update

A few things have changed on the  blog since its inception, mostly in the pages (see tabs above):

  • The About page has been updated
  • I have added a Books page for publications that I have found useful or inspirational.
  • Both the BugWeb and MacroWeb pages have new additions.

Comments, critiques and contributions are welcome.

Young Misumena vatia with prey

Young Misumena vatia with prey

Posted in Blog Also tagged , , , , |

Rock Flipping at Rampart Creek

While camping in the Rampart Creek campground on the Icefields Parkway, I did a bit of rock-flipping. There was sparse pickin’s, but I found these two under one rock. Not disturbed by the sudden inversion of their world, the fly, which had a mantid-like stance, immediately pounced on the winged ant (Formica sp.) I quickly brushed them into my macro studio, which separated them, and they declined to perform after that. But neither flew away either – the ant due to a possible misplaced wing and the fly due to its nature – according to Stephen Marshall’s book¹ the fly, called Tachydromia (sub-family Tachydrominae) is an ant-like predator,  and, “Although fully winged, they are reluctant to fly.“, which matches the behaviour of my specimen as well.

(Thanks to James Glasier and Jason Dombroskie at the University of Alberta for helping to ID the wee beasties)

(Nikon D80 with a 50mm F1.8 Zuiko lens reverse mounted on a Tamron 90mm macro lens and Kenko Pro 1.4x teleconverter. Lighting – Nikon SB-600 with wide-angle diffuser. Subjects in white bowl.)

¹ Marshall, Stephen A. 2006. Insects. Their Natural History and Diversity: With a Photographic Guide to Insects of Eastern North America. Firefly Books ISBN-13: 978-1552979006
Posted in Alberta, Autumn, Diptera, Hymenoptera, Insect, National Park, White Studio Also tagged , , , , |