Glommed onto Bombus vagans tongue at Trifolium pratense along roadside.
body length 31 mm; under bark on trunk of eucalypt
This beetle was darting in and out investigating holes in this rotting tree trunk. I didn't realize that they could move so rapidly having only previously seen them nearly motionless and surrounded by Crematogaster ants.
As this is the third observation of similar encounters between this species of beetle and members of this same colony of ants, I assume this is a routine occurrence because days pass between my visits to this site. It seems that these ants perceive these beetles to be a threat to the colony. I read that their larvae are ectoparasites of the pupae of other insects.
Tiny: 2mm long. Several crawling around Brittle Cinder/Kretzschmaria deusta fungi at base of Linden/Tilia. Fungi observation: https://www.inaturalist.org/observations/217333956
These ants are hauling this beetle up the trunk of a large standing dead tree.
The beetle was attached to the tongue of a Common Eastern Bumblebee, Bombus impatiens. Phoresy
3mm long, under hardwood in riparian zone. Elongate pronotum is distinctive for NA Europini according to bugguide: https://bugguide.net/node/view/375170. Keyed to Macreurops in Arnett.
Minute Clubbed Beetle, Bactridium, came out of Phylloxera gall on hickory leaf
3mm, from under the bark of Abies magnifica.
Denticle behind eye suggests P. ommatodon from https://digitalcommons.unl.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1047&context=insectamundi, but notes here are curious: "A single specimen in SBMN with label
data: ìCA: Tulare Co. 36.950o
N, 118.353o
W Sequoia
NF; Mosquito Mdw. vi.24.2003; M. Caterino under
bark Abiesî, cannot be placed. It is similar to P.
ommatodon, but the denticle behind the eye is about
twice as long. Unfortunately, it is a female and
resolving its status will have to await collection of
male examples."
I saw an Eastern Bumblebee on a Rattlesnake Master flower reared up on its hind legs and holding very still. There was a tiny beetle, likely a Silken Fungus Beetle, firmly clamped onto the bee's proboscis with its mandibles. These beetles practice phoresy: they live on flowers but attach to a leg, antenna, or mouthpart of a bumblebees and hold on until they are transported back to the bee's nest. There they lay eggs and the resulting larvae feed on organic debris in the nest. The bee held still for the entire 5 minutes or so that I observed it. I cross posted this under Eastern Bumblebee here:https://www.inaturalist.org/observations/128056037
This bee was reared up on its hind legs and appeared to be in distress. In the images there is a tiny brown beetle biting the bee's proboscis. They stayed this way for 5 or more minutes before I walked away. Edit: Looking into it, I think the beetle is Antherophagus ochraceus, the silken fungus beetle, which clamps onto bumblebees and hitches a ride back to the nest. The beetle lays eggs in the nest and the resulting larvae eat organic debris.