Crane fly of some kind ? - Alotanypus venustus

Moved

Moved from Thienemannimyia.

It turns out there is an error in the key I used to identify this as Thienemannimyia. The feature distinguishing Pentaneurini from Macropelopini is not reliabile. Normally Macropelopina has the costa extended well past R4+5 while Pentaneurini has C ending at R4+5. Occasionally a midge in Macropelopini will have a shorter than usual C. That's what happened here. Thienemannimyia is the best match in Pentaneurini. Looking at all the factors, and accounting for the occasional shortened vein, Alotanypus venustus wins.

… John F. Carr, 28 January, 2009 - 8:09pm

Moved

To new genus page.

… tom murray, 16 December, 2008 - 7:53am

Female midge

Looks like subfamily Tanypodinae. The wing veins are the main diagnostic characters to tribe level in midges. If you have a closer picture of the outer half or so of the leading edge of the wing, that would help confirm ID. Also helpful, potentially, is a shot of the back half of the thorax. A shot as close as the head shot might let me count hairs; those are used in the key at the species level.

… John F. Carr, 16 November, 2008 - 8:00pm

Thank you John

for the subfamily ID. I've added closer views of the thorax and wing that might help with the ID.

… Gary McDonald, 16 November, 2008 - 8:51pm

Pentaneurini

This is subfamily Tanypodinae, tribe Pentaneurini. We don't have a page for the tribe (not enough images to justify one) so this can go to the subfamily page for now(1). I can rule out most of the tribe. I haven't figured out a genus.

These are good closeups. Part of the problem is, there is no description of the female of many species. Gross features tend to be the same as the male, but part of the diagnosis involves ratios of antenna and eye parts which are very different between male and female midges. It may be helpful to have a shot including the feet. The pattern of leg banding is sometimes useful (e.g. two tarsi might be light brown and three dark brown).

… John F. Carr, 17 November, 2008 - 4:00pm

Thank you John

I've added a photo which shows the feet, to help with ID. I can post a closer view of one leg if needed.

… Gary McDonald, 17 November, 2008 - 7:14pm

Feet

A closer view of a leg may be helpful. It can at least help rule out some genera -- the shape of the fourth tarsal segment is a diagnostic feature.

You have a set of wings that is a very good match for Ablabesmyia, and much less good for any other genus in the subfamily, but that genus always has three brown bands on the tibia according to the key. In general only males have been described. The one female in the book is described as having identical leg banding and the pictures we have here match too.

… John F. Carr, 18 November, 2008 - 8:29pm

Thienemannimyia

My best guess now is Thienemannimyia barberi; I've asked for a new genus page because it's a good match for the genus even though I'm not sure about the species. The legs are closer to T. barberi, the wings to T. norena. I don't have a drawing of the female wing of T. barberi.

… John F. Carr, 15 December, 2008 - 4:31pm

Thank you John

for the genus and probable species ID.

… Gary McDonald, 16 December, 2008 - 9:28am

Thanks again John

I've added a closer view of the rear leg to help with ID.

… Gary McDonald, 18 November, 2008 - 8:54pm