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larvae living in a quiet and sandy freshwater, collected yesterday




Who can tell me what are these tapering projections we see on the different abdominal segments (different of the hooked prolegs)?
Are they gills too ?
Is this larvae Atherix sp or Atherix Ibis ?

thank you
SDS


YouTube Video

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These lateral projections on the abdomen are too long for Atherix. So this must be Ibisia marginata. According to the literature: Atherix should have the integument appearing smooth and clean while in Ibisia it appears rugose and frequently covered with particles or chalc concretions (at low magnification) but I can't see that. The tapering hairy prolongations at the end do not have an actual gill-function but it uses it as floating hairs and lobes so their actual posterior spiracles will come into contact with the surface. Were did you collect it?
By the way if it was Atherix, you couldn't identify it to species level for A. flavipes haven't been described as larvae.

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Hello... glad to receive your message
I found this individu in the Aisne river
here


Do you believe I can let Atherix or make change to Ibisia ?
Nevertheless, this organism is an Athericidae, isn't it ?

merci
Solito

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Ibisia marginata it is, which is Athericidae
May I suggest to add your record to http://observado.org/

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Veel bedank, Heer Atylotus
Your suggestion observado will receive my attention

I post here a few details of this larvae ( after two days left in the sample without alcohol or whatever formaline)

last floating hairs



first proleg hooks


first proleg (one of)


head


antenna ?


lauterborn organs ?


last and single big proleg (double sized)


spines on the "skin"


sided projection articulation


last abdominal segment side hairs



eyes



merci
SOlito