Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Home
» Guide »
Arthropods (Arthropoda)
»
Hexapods (Hexapoda)
»
Insects (Insecta)
»
Beetles (Coleoptera)
»
Adephaga
»
Predaceous Diving Beetles (Dytiscidae)
»
Agabinae
»
Agabini
»
Ilybius
»
Ilybius biguttulus
Photo#1481578
Copyright © 2018
Marci Hess
Ilybius biguttulus
Argyle township, Lafayette County, Wisconsin, USA
August 5, 2017
Size: 11mm
Caught in solar bucket trap
Images of this individual:
tag all
Contributed by
Marci Hess
on 2 January, 2018 - 3:42pm
Pardon me for asking
but is the measurement for this specimen precise or just a guess?
…
Claude Tessier
, 7 January, 2018 - 3:04pm
I used a ruler.
It's not a super accurate metric ruler but I'm confident this size is within 1/2 mm or so.
…
Marci Hess
, 7 January, 2018 - 3:54pm
Then it could be 10,5 mm long
Because I did see many many
I.biguttulus
but none were that long. If the measure is more on the 11 side then, for your area, you are left with three species:
I. subaeneus
,
I. pleuriticus
and
I. confusus
. It would be interesting to take another look at that specimen to see if it still holds...For myself I can't say just by looking at these images.
…
Claude Tessier
, 7 January, 2018 - 8:34pm
I re-measured.
It's definitely between 10-11mm. According to Evans book on Beetles of Eastern North America this species is 8.4-11.4mm. I looked at
I. pleunticus
and don't see the white spots on the lower elytra in those photos that I could see.
I. subaeneus
and
I. confusus
are special concern listings here in Wisc. I'm meeting with a local beetle expert on Wed. I'll see if he can determine which species this is. Thanks for all your help.
…
Marci Hess
, 8 January, 2018 - 11:22am
ID confirmed
Striations on hind coxal plate and side are diagnostics. Hind margin of pronotum and head have a reddish, rather transparent margin.
(
1
)
Det Jordan Marche'
…
Marci Hess
, 11 January, 2018 - 2:21pm
Good!
Thank you for the information!
…
Claude Tessier
, 14 January, 2018 - 4:39pm