yellow bettle? aquatic?
Location: Raymond, California
August 7, 2011 3:45 pm
I saw these two insects this morning in one of our creeks. They were both approximately the same length, but obviously different colors. The yellow one was firmly grasping the dark one – mating? Predation?
I am clueless on ids for both of them. Any ideas?
Signature: Megan Ralph

Giant Water Bug Nymphs compete for meal

Hi Megan,
We are confident that we have identified your insects as two immature individuals of a species of Giant Water Bug in the genus Abedus, based on this image of Abedus herberti posted to BugGuide.  The yellow individual in your photos and the BugGuide image are newly molted nymphs in the teneral stage, meaning that their exoskeleton has not yet hardened and darkened.  Insects are especially vulnerable immediately after metamorphosis.  We believe the dark individual in your photos, also a nymph, is taking advantage of its weaker coeval by preying upon it.  Of course, your photos do not reveal the final outcome, and the teneral individual may have actually been the victor in this food chain drama.  BugGuide has a wealth of information on Abedus herberti, including this listed range:  “Arizona, Utah, New Mexico, USA; northern Mexico” and this listed habitat:  “Freshwater streams, especially in montane areas. They often inhabit intermittent streams, so they are isolated to individual rock pools (tinajas) during dry periods when streams do not exhibit overland flow.”  This interesting note of food may explain the cannibalistic behavior that your photo illustrates:  “All water bugs are predators. Abedus herberti eats other insects, small fish, small tadpoles, and will become cannibalistic when other food is scarce.”  One final bit of information from BugGuide indicates that this might actually be a closely related species from California, Abedus indentatus:  “Abedus is a difficult genus in which to identify species without a microscope for close examination. A. heberti is similar in appearance to most other Abedus species, but it is most similar to Abedus indentatus. A. indentatus is typically only found in California.”  BugGuide has a dearth of information on the California species.

Cannibalistic tendencies in Giant Water Bug nymphs

Thank you so much for your detailed and extremely informative reply.  That is the perfect description for the habitat where I saw them – a small stream that is beginning to dry up (rather late in the year actually – it was a wet spring).
Megan

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Unknown creature who washed ashore…(I don’t think photo went through last time, sorry)
Location: Indiana Dunes National Lakeshore, wet sand at southernmost end of Lake Michigan.
August 9, 2011 7:11 am
We were on the beach in the Indiana Dunes National Lakeshore when I noticed this bug(?) moving in the sand after a wave washed it onto the beach. Even though I’ve taken multiple wildlife courses in the Dunes and could identify every sand cherry and jack pine growing there, I’m at a loss with this little guy.
One thing that doesn’t come across well in the photo is that this creature seemed to have beady little eyestalks that moved independently. For that reason, I thought this was some sort of freshwater crustacean at first glance, but it doesn’t look too much like a shrimp either.
I’d love to learn about this little guy.
Signature: Kitsa

Water Scorpion

re: beach bug
Location: Indiana Dunes National Lakeshore, wet sand at southernmost end of Lake Michigan.
August 9, 2011 7:22 am
After some more research (just had to get myself pointed in the right direction), I see that it’s a water scorpion. Glad I kept my distance, but what a neat bug
Signature: Kitsa

Dear Kitsa,
We are happy to see that it took you only 11 minutes to self identify your Water Scorpion and to write back letting us know.  While they are not dangerous, Water Scorpions are reported to have a painful bite.  They are True Bugs that have piercing mouthparts adapted to sucking fluids from their prey, mainly small aquatic creatures including insects, tadpoles and even small fish which they catch with their raptorial front legs while waiting camouflaged among vegetation.

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