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 Brachypterous Ephydridae
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| Paul Beuk |
Posted on 21-12-2007 09:10
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 Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Can someone give me a quick pointer to what brachypterous (or in this case polymorphic) species of Ephydridae we have in Northwestern Europe. I go a small sample of smallish Ephydridae from a pitfall which superficially look conspecific, but one specimen is brachypterous. I only have a very outdated key to dive into, so if someone has a lead for me to ease my struggle...
Paul - - - - Paul Beuk on https://diptera.info |
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| David Gibbs |
Posted on 21-12-2007 10:47
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 Member Location: Bristol, UK Posts: 833 Joined: 17.06.06 |
try Philygria (including Nostima) semialata (Collin, 1913) mocsaryi nubeculosa stenoptera |
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| Tony Irwin |
Posted on 21-12-2007 11:25
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 Member Location: Norwich, England Posts: 7193 Joined: 19.11.04 |
None of the species David suggests has a macropterous form, as far as I know, although there are similar, related species that are macropterous (but they are not usually collected in pitfalls!  ). The only genus of which I am aware that has both macropterous and brachypterous forms in the same species is Limnellia - they are recognised by the spots on the wings. Both suturi and quadrata have been found as brachypterous forms (the subject of a paper which awaits completion - Oh, for a few more free days!!  )
Tony ---------- Tony Irwin |
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| Paul Beuk |
Posted on 21-12-2007 14:09
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Despite what you mention, Tony, it appears they are Philygria. I will check Hollmann-Schirrmacher's monography on Ilytheinae, that gives special reference to Philygria.
Paul - - - - Paul Beuk on https://diptera.info |
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| Tony Irwin |
Posted on 21-12-2007 16:54
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Member Location: Norwich, England Posts: 7193 Joined: 19.11.04 |
Interesting ... I wonder if these are Philygria (=Nostima) picta - in this species both sexes have reduced wings, but the reduction is more extreme in the female (- sexual dimorphism rather than polymorphism). Among the Philygria that David suggests, semialata was originally placed in Nostima, distingished by plumose arista and two, rather than three, dorsocentral pairs (including pre-scutellars). It is a species that is most often recorded by pitfall trapping, in Britain associated with grassy heaths. If you have found a different Philygria with fully macropterous and brachypterous forms, then that is certainly remarkable! In any case a good find! 
Tony ---------- Tony Irwin |
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| Paul Beuk |
Posted on 21-12-2007 19:56
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
The specimens indeed have two pairs of dorsocentral setae and the arista has rather longish hairs dorsally. As far as I could tell (the specimens are at work and I am at home now for almost two weeks) the brachypterous specimen was a male and there were males among the other specimens as well. The fully winged specimens do not have really large wings, true, the tips just extend over the tip of the abdomen. I have not yet checked Hollman-Schirrmacher.
Paul - - - - Paul Beuk on https://diptera.info |
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| Paul Beuk |
Posted on 22-12-2007 20:38
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Hollmann-Schirrmacher does not make me very happy. There is no key to all Philygruia species but only to those with a single row of acrostichals (my specimens have none). Furthermore, there are a number of species with 'reduced wings', which I think are similar to the 'macropterous' specimens I have (wing tip then probably at level of abdominal tip). But my brachypterous specimen is truely brachypterous, so wing even further shortened and narrowed, so that the wing venation is also reduced: the major veins are the radial veins and vein M1+2 (the costa extending to that vein), but no veins posterior of that because there practically is not any wing left there. Non of the species mentioned by Hollmann-Schirrmacher seems to want to accomodate that specimen of mine. But there is one 'maybe': One way or the other, semialata is not mentioned by Hollmann-Schirrmacher... Due to some unclear references in the book I cannot be entirely certain why the species is not mentioned. Of the former genus Nostima only picta and flavitarsis are mentioned and according to him it should be substantiated elsewhere in the book why other species (he does not even mentioned which ones) are not discussed. Possibly semialata is one of them. Oddly enough, he mentions that THE species of Philygria are discussed in chapter 4.5. Well, not all of them it turns out. Paul - - - - Paul Beuk on https://diptera.info |
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| Tony Irwin |
Posted on 22-12-2007 22:01
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Member Location: Norwich, England Posts: 7193 Joined: 19.11.04 |
I think Hollmann-Schirrmacher only set out to monograph Philygria s.s. In the process, his cladistic analysis suggested that Nostima should be included within Philygria, but he didn't deal with all the Nostima species (probably not having access to semialata among others). From your description of the venation, they certainly sound like semialata. Collin figured the wings in his paper in The Entomologist - unfortunately don't have a copy here which I can scan for you. Let me know if you'd like a copy after Christmas! Tony ---------- Tony Irwin |
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| Paul Beuk |
Posted on 22-12-2007 23:00
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Do you need to ask? Yes, please!
Paul - - - - Paul Beuk on https://diptera.info |
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| Paul Beuk |
Posted on 27-12-2007 21:25
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Today I received Tony's reprint in pdf format. Preliminary: The one true brachypterous specimen I have has the wign as illustrated for the semialata female (but in my recollection it was a male). However, all other specimens have significantly larger wings than was illustrated for the semialata male. So even if I am screwing up the sexes (plz, no comment required  ) I think that the 'macropterous' specimens might be something very interesting. So,...Anyone have material of semialata I can study? 
Paul - - - - Paul Beuk on https://diptera.info |
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| Tony Irwin |
Posted on 27-12-2007 23:03
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Member Location: Norwich, England Posts: 7193 Joined: 19.11.04 |
I know I have some in alcohol somewhere (presumably yours are the same) - I may be able to sort them out next week .... (unless someone has some more accessible!)
Tony ---------- Tony Irwin |
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| Paul Beuk |
Posted on 04-01-2008 09:33
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Super Administrator Location: Netherlands Posts: 19240 Joined: 11.05.04 |
Well, the brachypterous specimen is P. semialata, a female. Not previously recorded from the Netherlands. The 'macropterous' specimens actually have much bigger wings than I remembered. That is probably due to the fact that the same sample also had some brachypterous Chloropidae of the same size and coloration (in alcohol all those lovely dust patterns on the Ephydridae are invisible). These 'macropterous' Philygria were indeed Philygria and, oddly enough, they were P. picta, precisely the other species with two pairs of dorsocentral setae and no acrostichals. Any thoughts on what the chances would be that both occur together? Paul - - - - Paul Beuk on https://diptera.info |
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| Tony Irwin |
Posted on 04-01-2008 15:16
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Member Location: Norwich, England Posts: 7193 Joined: 19.11.04 |
Despite its widespread disribution (from Canada to Guatemala in the Nearctic and from the Azores to Japan in the Palaearctic), not much is known about the ecology of Nostima picta . It probably has a fairly wide habitat range, so it is quite possible that both species will occur together.
Tony ---------- Tony Irwin |
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