I found these unusual bugs mating among my sweet alyssum today. They appear to be one of many insects I've observed lately taking favor to reproducing on my sweet alyssum. Thanks to anyone who can help me identify them. Oh yeah, and please be sure to specify whether they are beneficial or pest. Thanks again!
You may get a quicker ID if you post your picture in the Insect and Spider Forum. the folks there are very knowledgeable.
Looks like some kind of beetle. Are you noticing any damage? Beetles hang out everywhere, and can be plant pests or not. They could be just hanging out, find it a nice lovemaking environment, feeding on sap, really chomping on the plant (which is the most common way beetles feed) or even eating smaller bugs that are on the plant. Look close, keep and eye on them, but don't nuke them unless they really seem to be causing damage. That's my 2 cents anyway.
thanks all for your replies. i'm not sure but when i googled "orange and black insects" i noticed these insects appear to be very close in appearance to the australian stink bug which i read can be a pest. and yes, they appear to be eating the foliage of my sweet alyssum (but not to the point of alarm or destruction) and reaching adult size rather quickly. now i wonder if the tiny "ladybug-like" babies (see pic) I first saw on my alyssum were actually these insects all along? (i was concerned at first that perhaps these insects were eating what appeared to be the baby ladybugs since the google description of this particular stink bug noted they might even eat ladybugs if necessary.) i have no idea still what i am looking at but i will monitor as one of you suggests, thanks. to-be-continued...
Maybe one of the assassin beetles/bugs
It's a Bagrada bug, a species of stinkbug recently invading California:
http://www.cdfa.ca.gov/phpps/PPD/PDF/Bagrada_hilaris.pdf
http://www.infonet-biovision.org/default/ct/103/pests
