Thread subject: Diptera.info :: Acalyptrates: tergite number confusion

Posted by Louis Boumans on 25-04-2013 14:31
#1

Following the nice online Anatomical Atlas (http://www.ces.csiro.au/biology/fly/flyGlossary.html) tergite 1 and 2 are fused in Acalyptrata but not in any of the other Diptera groups.

Firstly, is that correct?

Then, I understand that part of the litterature refers to the anatomically 6th tergite when discussing the 5th tergite. So how to avoid confusion? E.g. "the 5thvisible tergite - anatomically 6th - is yellow" ?

Posted by Nosferatumyia on 25-04-2013 18:15
#2

In all the modern keys, 5th tergite is ANATOMICALLY 5th tergite, and if the 6th tergite is present, this means anatomically 6th tergite, and nothing else!

When I describe the acalyptrate abdomens (I was the author of certain keys, for instance, in the Manual of Central American Diptera and the forthcoming Manual of Afrotropical Diptera), I always metion numbers of the anatomical tergites: "syntergite 1+2", "tergite 3", "tergite 4", tergite 5", "tergite 6", "tergosternite 7", etc.

Edited by Nosferatumyia on 25-04-2013 18:16

Posted by Louis Boumans on 26-04-2013 00:09
#3

Thanks Valery, that's clear! If one also mentions 'syntergite 1+2' it is also unambiguous.
Now, do you also happen to know in which groups tergite 1+2 are fused? As Acalyptrata probably is a paraphyletic assemblage, it seems unlikely to me that the tergites are fused in all Acalyptrata but not in Calyptrata.

Posted by Nosferatumyia on 27-04-2013 00:34
#4

Louis: it's well visible: the syntergyte is 1.5-2 times as long as the 3rd tergite and bears partly bare area of fusion, etc. I hardly can recall a case, when I had a problem with this.

Posted by Louis Boumans on 28-04-2013 16:54
#5

Thanks again, Valery, I'll try if I can see this too!