No interactions present.
With a bit of luck and rummaging, I might be able to locate and photo a fresh adult at the same spot this year.
Thanks for the info and links,
Was just having a glance at the plate of larger aquatic beetles in a book yesterday and noticed that D. lapponicus was given an upper size limit of 28m? This got me wondering because the portion of beetle pictured above was large. I might even still have it, with a bit of luck I'll find it.
I'd only be guessing if I offered a measurement, but Ive added a photo of the incomplete beetle against an average sized, if somewhat worn female emperor moth which I encountered the same day.
I could be completely wrong (youve given reasons for the ID of D. lapponicus above) but I feel this insect might be too large for lapponicus??
Look forward to your thoughts on this.
I havent changed my view in fact am more sure. I have a Dutch guide and one of the characters it gives is the presence of dark spots on the underside of the abdomen. You can just see them. Compare with this picture here. http://www.fugleognatur.dk/images/galleri/PICT0148-01.jpg So if you do find it take a picture of the underside from directly above so that the coxal lobes are clearly visible just like in this Danish picture.
I cant judge the size even against the moth
I just put a ruler against the illustrations of various Dytiscus species in my reference book. This explains my confusion- the illustration of lapponicus is only 22mm long whereas the upper size limit given is 28mm here. All the other Dytiscus illustrations are quite a lot larger.
One other little feature which drew my attention to marginalis and D. cirumcinctus also, which is visible on my beetle is the yellowish ribbon like markings on the trailing edge of the elytra. It appeared to be 'diagnostic' as it isnt depicted at al;l on any of the other species.
Sorry for the confusion, I shouldnt have assumed my plates were life size- lapponicus is pictured very small here (Freshwater Life by Greenhalgh 2007).
Ok, no bother, thanks for the link, if I find it I'll get some more images. What made me wonder was the size of the illustration in a little book I have compared to other Dyticus on the same plate, as the incomplete beetle above seemed to me to be atleast as long as the complete beetle in the diagram at 28mm.
Will take a look at the Danish example.
Yea thats a great picture, now I just need to understand what a coxal lobe is......
Lat/Lng: 54.991, -6.109
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