Thread subject: Diptera.info :: Insect's larva ?

Posted by pat_der2003 on 10-04-2020 12:42
#1

Hello,

In freshwater at the riverbank, April 09th 2020, France, 30km from PAris city.

About 0,85 mm / 850 µm ...

I'm wondering if it could be a fly's larva ? Or an annelid ? Or ... ?

In the picture below, a scale = 10 µm

Edited by pat_der2003 on 10-04-2020 12:42

Posted by pat_der2003 on 10-04-2020 12:43
#2

the head and body

Posted by pat_der2003 on 10-04-2020 12:43
#3

head and body

Posted by pat_der2003 on 10-04-2020 12:44
#4

head not contracted

Posted by pat_der2003 on 10-04-2020 12:45
#5

head again, contracted


Thank you in advance !! :)

Posted by Tony Irwin on 10-04-2020 17:10
#6

Probably an oligochaete. The "Y" shaped mouth is typical of leeches (though I think this one is in the wrong orientation), but only one order of leeches (Acanthobdellida) bears setae on the body, and they don't have an anterior sucker. So I would say an oligochaete or one of the few freshwater polychaetes (family Aeolosomatidae) - although this latter group do not appear to have setae on the prostomium.

Posted by pat_der2003 on 11-04-2020 05:36
#7

Many many thanks, Tony !! :)

Posted by atylotus on 13-04-2020 13:04
#8

Most likely Chaetogaster setosus. A small Oligochaete species with only simple pointed chaetae on the ventral side. This species is probably one of the smallest freshwater Oligochaete worldwide. Other Chaetogaster species have bifid chaetae and all other oligochaetes have dorsal and ventral chaetae. Did you collect it? I would like to have an ethanol preserved specimen.
It is no Aeolosomatidae for members have bundels of hairs dorsally and ventrally and NO Acanthobdella for those members are strictly North east European.

Edited by atylotus on 13-04-2020 13:06

Posted by pat_der2003 on 13-04-2020 19:49
#9

Oh, Thank You very Much Atylotus !!:)

Trying to follow the key "Thorp and Covich's Freshwater Invertebrates ", I was thinking of Aeolosoma species, but I was wrong for the absence of "bundels of hairs dorsally and ventrally" as you wrote ...
Thank you again.
Unfortunately the preparation went dry and it is lost ... :(

May be next time !:)