Tricrania sanguinipennis, a bee parasitoid

Found this striking, highly punctate beetle in my yard a few days ago and finally figured out what it is: Tricrania sanguinipennis, a blister beetle (Meloidae). Apparently a parasitoid of Colletes spp., ground-nesting bees that are often situated in dense aggregations. I have hundreds of digger bees in my front yard each year, so I’m guessing that some or all are Colletes, but I’m trying to confirm (casual guess is C. inaequalis, the unequal cellophane bee).

Colin Purrington Photography: Insects &emdash; Tricrania sanguinipennis

Per Parker and Böving 1924, female T. sanguinipennis deposit clumps of eggs near these aggregations and when larvae hatch they seek out adult bees and clamp onto body hairs with specialized mandibles. If the bee happens to be a female, larvae release their grip when she arrives at the brood cell, sometimes up to 2 1/2 feet underground. If the beetle larva has attached to a male bee it will move onto a female while the bees are mating. Once in the nesting chamber the larva will seek out the bee egg, eat it, then set up camp inside the cell (see fig 21, below) that holds the honey and pollen, which it will eat until maturity.

Below is Plate 3 from the Parker and Böving article. If you expand the image you can see that the bee has multiple larvae attached. I think I might need to capture a few of the bees this Spring to see whether I can find some of these hitchhikers. Am also trying to find the egg clumps, which can have thousands of eggs. That’s a lot of eggs for a beetle but the success rate of the larvae must be extremely small so they’ve presumably evolved large brood size to ensure that at least some find their way into a nest.

Tricrania sanguinipennis

Illustrations of Tricrania sanguinipennis larvae from Parker and Böving 1924.

Very cool beetle and just had to share the find. If you’d like to see more photographs, there are currently 27 sightings Tricrania sanguinipennis on iNaturalist. I highly recommend the Parker and Böving article for the biology details but mainly for how they figured out the details; it’s hard to figure these things out when the species spends its life underground. For more information on related beetles this page by Dr E. F. Legner (UC Riverside) is excellent.

Supranivean insects and spiders

Winter is usually a depressing down time for those who enjoy taking photographs of insects and spiders, but a fresh snowfall can reveal all sorts of critters still crawling around, albeit slowly or not at all. Below are 11 of my recent finds.

1. Some sort of cynipid wasp. It’s nearly wingless (subapterous), so likely a member (female, obviously) of the asexual generation that many of these wasps go through. If I knew the species I could provide a link to the gall they make (usually on an oak), which often looks very different from the gall made by the sexual generation. If you recognize the genus or species, please let me know. Or, if you are a member of iNaturalist, comment on the observation page. Hildacy Farm, Media, PA.

Asexual cynipid in snow

2. This is probably a queen Lasius claviger. This species is a social parasite, so she might be out looking for a nest of some other species in the genus. I couldn’t find any report of queens being active during the winter so perhaps there’s another explanation. This individual was one of two I found, separated by several feet. Thanks to Gordon C. Snelling on iNaturalist for genus ID. If you think my species ID is wrong, you can correct me on iNaturalist (with thanks). Hildacy Farm, Media, PA.

Lasius claviger (queen)

3. Fly in the genus Simulium, per suggestion by John F. Carr on BugGuide. Here’s the iNaturalist page if you know the species and care to leave a comment. I’d even be grateful for a subgenus guess. It’s a black fly, but I’m not sure whether all of them are biting. Hildacy Farm, Media, PA.

Simulium sp. in snow

4. This seems to be a fly in the genus Pollenia, notable perhaps because they parasitize earthworms, which was news to me. Perhaps I’m easily impressed. Saratoga Springs, NY.

Pollenia sp. in snow

5. Here’s another fly from Saratoga Springs, and I think it’s also a Pollenia. Also not moving but in this case likely dead (its thorax seemed crushed, though ventral view doesn’t show it. If you have ID thoughts, here’s iNaturalist page.

Pollenia in snow

6. This a male Chironomus crassicaudatus. A tad contorted and not moving so not the best photograph. Thanks to John F. Carr for ID. Here’s the iNaturalist page if you’re curious. Hildacy Farm, Media, PA.

Chironomus crassicaudatus (male) in snow

7. This female fly was a few feet away from the male above, and is perhaps the same species. But definitely in the same tribe (Chironomini). Thanks, again, to John F. Carr for identification. I’ve also posted the photograph on iNaturalist if you want to weigh in on identification. Hildacy Farm, Media, PA.

8. Another fly in the genus Simulian, per Katja Schulz on iNaturalist. Sure looks like the images on the (Psilozia) vittatum species complex page on BugGuide. Hildacy Farm, Media, PA.

Simulium sp. in snow

9. Lygus lineolaris, per an identification on iNaturalist. Hildacy Farm, Media, PA.

Tarnished plant bug (Lygus lineolaris) in snow.

10. Some type of crab spider (Thomisidae). I haven’t been able to ID further. If you have thoughts, please see the iNaturalist observation page. Hildacy Farm, Media, PA.

Thomisidae in snow

11. Long-jawed orbweaver, probably Tetragnatha. The strange thing about this spider is that I found it several feet away from where I found Tetragnatha in the snow one year before. So I was actually looking for a Tetragnatha in the snow when I found it. If you are a member of iNaturalist and want to comment on the species … here’s the page. Hildacy Farm, Media, PA.

Tetragnatha sp. in snow.

Sadly, I didn’t find any snow flies (Chionea) but here’s one I found several years ago. This post has details.

Colin Purrington Photography: Insects &emdash; snow-fly

Exobasidium ferrugineae

I found this fleshy, flower-like structure growing on Lyonia ferruginea (rusty staggerbush) at Archbold Biological Station (Venus, Florida). Heaths don’t make flowers like this, so I originally thought it might be an insect gall or phytoplasma infection, but I was wrong. After poking around online I think it’s Exobasidium ferrugineae, a Basidiomycetes fungus. Members of the genus grow in between cells of flower and leaf tissue, then in the Spring send hymenial tissue through stomata and other cracks in the epidermis, eventually turning the surface white with spores. I’d never heard of such fungi before. I’ve led a sheltered life.

Colin Purrington Photography: Fungi &emdash; Exobasidium ferruginea on rusty staggerbush (Lyonia ferruginea)

The above was the largest structure I found (perhaps 3 inches high) but there were dozens of others (see below) at the same location. If you’d like to know more about the species and genus, a good starting point is Kennedy et al. 2012 and references therein. In older literature the fungus was known as Exobasidium vaccinii (Burt 1915), but it seems likely that that species is host specific to Vaccinium vitis-idaea.