nightfly's picture

Hatching aquatic insects?

Observed: 3rd July 2011 By: nightflynightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebrates
3 July 2011 (120)
3 July 2011 (123)
3 July 2011 (122)
Description:
Identifications
  • Aquatic fly.
    Confidence: It's likely to be this, but I can't be certain.
  •  
    Likely ID
    alderfly (Sialis)
    Confidence: It might be this.
    ID agreements (): 4 People
    • DavidNotton
      Natural History MuseumNatural History Museum
      Invertebrates expert
    • nightflynightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebratesnightfly’s reputation in Invertebrates
    • Peadar na BreacPeadar na Breac’s reputation in InvertebratesPeadar na Breac’s reputation in InvertebratesPeadar na Breac’s reputation in InvertebratesPeadar na Breac’s reputation in Invertebrates
    • Ian WallaceInvertebrates expert
Species interactions

No interactions present.

Comments

DavidNotton's picture

prolegs

difficult to see but the larvae appear to have prolegs, if so wouldn't this exclude Diptera?

nightfly's picture

Hi David, could you elaborate

Hi David,
could you elaborate a little? I dont know what prolegs are?

Excluding diptera, could you offer examples of what it might be?

Bear with me, I really havent got a notion of what Ive photographed, but I'd like to know, does it resemble lepidoptera at all?

These larvae were going to drop into water, indeed some already have done. As to whether they actually want to find themselves in water or not I havent the slightest idea, but it would seem that the insect that layed the eggs on this aquatic plant did so intentionally?

Thanks,

Cathal.

DavidNotton's picture

possibly beetles?

sorry I meant true legs, not prolegs, true legs are the ones on the front three thoracic segments whereas prolegs are the fleshy ones on other segments in caterpillars and sawflies (have caterpillars on the brain at present). There are leg like structures visible which might be true legs e.g. on the left side of the third image.

So I suggest possibly Coleoptera which do have true legs, not Diptera which don't, probably not Lepidoptera which would be more caterpillar shaped, not bugs which would be like mini-adults, possibly not caddis flies often make a jelly case. There are many species of aquatic/amphibious beetles of course, does anyone know what the eggs of Donacia look like?

John Bratton's picture

I think Donacias insert their

I think Donacias insert their eggs into the hostplant but I'm not certain.

DavidNotton's picture

Sialis

good suggestion, fits well, there are similar eggs pictured on the web, the larvae have thoracic legs and they would be laid near water

nightfly's picture

Thank you John, that did

Thank you John, that did cross my mind but it was one of many many possibilities, I really hadnt got a clue. Yes alderfly are present there.

Thank you.

Cathal.

John Bratton's picture

I've looked in Menzies & Cox

I've looked in Menzies & Cox 1996. They say Donacia spp. lay eggs in clusters in gelatinous envelopes on submerged leaves and stems or undersides of floating leaves. Plateumaris spp. lay on foliage above water.

DavidNotton's picture

Thanks!

That's interesting about the Donacia