Water Boatman id

[col188]

Discovered whilst cleaning the Conservatory guttering. Two of em were quite happy swimming around in a flooded section.
Are they the same species or is one/all three Sigara striata or Corixa punctata.
They were differing sizes
Col

[JRsbugs]

Hi Col,

I saw your pics when looking at others, I don't visit this forum but these are beetles. I have had a couple of different ones in my new pond, one I have narrowed down to Sigara nigrolineata. There's a few which look very much the same but there is slight differences. Your middle one looks to have the same markings.

Not sure about the other two, but you would think they were the same, maybe not.

Janet

[col188]

Originally Posted by JRsbugs

Hi Col,

I saw your pics when looking at others, I don't visit this forum but these are beetles. I have had a couple of different ones in my new pond, one I have narrowed down to Sigara nigrolineata. There's a few which look very much the same but there is slight differences. Your middle one looks to have the same markings.

Not sure about the other two, but you would think they were the same, maybe not.

Janet

Thanks Janet.

Was going to put them in Insects & Invertebrates....... but wrongly thought water+swimming = Amphibians!
The last two are the same, but one was longer and narrower, I think it was the first one. There were two of them, but not sure of which is which on the pics.

Col

[Wild-Woman]

I would say these are Corixids. Also known as Lesser Water Boatmen.

[JRsbugs]

I found Corixid too but there's a few others I found which match better.

Col, the last one is likely the same but I can't see the pattern on the tail tip.

I just lost my post after not finding the pic I uploaded, grrrr.

Here's mine, will see if I can find the evidence tomorrow, it's late!

[col188]

Originally Posted by JRsbugs

I found Corixid too but there's a few others I found which match better.

Col, the last one is likely the same but I can't see the pattern on the tail tip.

I just lost my post after not finding the pic I uploaded, grrrr.

Here's mine, will see if I can find the evidence tomorrow, it's late!

Yours seems to match theses two Janet

[

But this one appears longer & narrower



Col

[JRsbugs]

Originally Posted by col188

Yours seems to match theses two Janet

[

But this one appears longer & narrower



Col

Yes I agree the first looks different, it's a cold horrible day so I don't have to go out to take yet more pics, lol, will get around to checking them out properly soon!

[JRsbugs]

Look at the superfamily DIPSOCOROMORPHA then scroll down the the subfamily Corixidae, there you will find a link for a pic of Sigara nigrolineata. They are common here if you check the nbn gateway.

Heteroptera - Bug Photo Gallery - Foto Galerie Wanzen

So yes they are Corixids as stated by Wild-woman, but not the genus Corixa.

Now to look for the first one!

[JRsbugs]

Look at the same site and check out Sigara striata, that one looks the closest for your first and it does look longer and narrower. The patterning on most is very similar but there are subtle differences making life hard for us!

[col188]

Thanks Janet....... I follow your reasoning.
That's why they stick em on pins, do dissection and use microscopy for IDs.

Heard often but finally sinking in.... 'IDs can't be accurately achieved from a photo'

Col