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Confused (2 Viewers)

Odonate

Well-known member
Hi all

I am utterly confused by whatever is below. Caught in a good quality stream in South Devon today in a kick sample while demostrating the technique, the ID and BWMP in general to a group of (relatively willing this time!) students. I was going through the trays at the end to see what anyone might have obviously missed.

I assumed it was a leaf bud so was tossing it out but to the touch it clearly wasn't and was a firm gelatin like texture. Backlight, there was a larva inside but the dark colour made it hard to see. Not dissimilar to a caddis larva from what we could make out and some suggestion of appendages with hooks at the rear but like I said, hard to see. c. 1.5 cm length but no apparent openings at either end.

I am aware that the answer may be to cut it and have a proper look but if there is a really obvious answer that I am missing then I can avoid that. I have sampled that stream and nearby ones many times during teaching activities and either never seen, or perhaps more importantly, noticed anything similar.

Any pointers gratefully received because I am totally lost even at order level.

O

Larva.jpg
 
Looks like a water bug egg?

 
Im not claiming anything new and the most reasonable explanation I have had so far is a Caseless Caddis Pupa - anone any experience in these?
 
Looks like a water bug egg?

But an egg wouldn't have a fully formed larva inside or am I missing something?
 
But an egg wouldn't have a fully formed larva inside or am I missing something?
How do you know if it was FULLY formed? It could have been minutes/hours/days from hatching.
Think about a chicken's egg. The embryo grows and develops until one day, nature decides it has developed enough and hey presto, it hatches.
 
How do you know if it was FULLY formed? It could have been minutes/hours/days from hatching.
Think about a chicken's egg. The embryo grows and develops until one day, nature decides it has developed enough and hey presto, it hatches.
Because then it wouldn't be an egg? There was no entrance or exit so how did it eat or shit as an invert? How did it get the nutrients? Yolk provisioning in a chicken is an entirely different thing because the egg (via the yolk) is the food source. There is egg provisioning in insects but the analogy is flawed. And trust me, it was "fully" formed. Nature does not decide and there is no "Hey Presto", these are processes that are understood at fundamental biochemical levels. What do you want it to hatch in to? A late instar larva which defeats the object of having a provisioned egg or a larval stage or an adult which makes no sense in a holometabolous species? Larvae are eating machines that do the other way round and provision the adults which are often devoid of mouth parts. Notwithstanding that Devon is a long way fom the native range of what you suggested and it is highly unlikely in the face of more convincing arguments. Google is not that great at this. People here are, and I am never even comparing my knowledge to any of them hence, the humility of my original post. Oh, and you are a continent away which is not impossible but unlikely.
 
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@Odonate. Just a follow up, as I am, like you, confused.
You stated:
Not dissimilar to a caddis larva from what we could make out and some suggestion of appendages with hooks at the rear but like I said, hard to see
Now you say:
And trust me, it was "fully" formed.
All I was doing was putting forward my thoughts and ideas.
Also, Cornwall, where I live, isn't, as far as I am aware, on a different continent from Devon.
 

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