Tag Archives: Insects

Cutworm parasite

I’m doing a short write up of this fly just to get you thinking a bit.  It was observed April 29, 2024 on San Juan Island, WA. While identification to Genus/Species may not be possible until I can actually catch a specimen to be keyed out, it is Family Tachinidae and Tribe Goniini.   Hoping to come back with at least a Genus update at some point. 

What I want to SHARE is the life history of this tribe of flies.  The Goniini flies are parasites of various Lepidoptera, mostly Noctuids, Arctiids, and Lymantriids.  Translating this for you a bit, it would be cutworms (if you’re a gardener) , tiger moths, and tussock moths.  

How does this play out? 

The female Goniini fly lays a “black microtype,” usually ovate and flattened egg, varying in size from very small to medium, on foliage utilized by the feeding host caterpillar.  The caterpillar (usually Noctuids) munch the foliage, ingesting the fly egg.  The caterpillar will continue feeding and then wander off to complete its life cycle as a pupa. At some point after ingestion by the caterpillar, the fly egg hatches and the fly larva develops inside the body of the pupating moth that is inside its chrysalis.  

A myriad of ecological relationships exist in nature that are often unobserved. Many remain undescribed or unknown. Sometimes, they are disrupted by humans who intervene out of ignorance. If you’re one of those folks who squish what you believe are cutworm pupae in your garden bed, you might be smooshing the pest predator developing inside.

Noctuid moth pupa

References

  1. No Author. 2024. Tachinidae. Spencer Entomological Collection. Beaty Biodiversity Museum. https://www.zoology.ubc.ca/entomology/main/Diptera/Tachinidae/
  2. Wood, D. M. 2013. Manual of Nearctic Diptera. Tachinidae Resources. https://www.uoguelph.ca/nadsfly/Tach/Nearctic/Manual/Manualhome.html
  3. Cole. Frank, R. 1969. The Flies of Western North America. University of California Press. Berkeley, CA.

Dance with me

I had an amazing BUG day!  It’s always amazing when you find one as interesting as this one.  Check out the proboscis.  

This is Empis barbatoides, I believe, a species of Dance fly in the family Empididae.  SHE (you can see her ovipositor at the end), was in the back of my truck on some cardboard I am using for landscaping.   


I find the behavior of these flies to be so interesting.  When they are in mating swarms, the male flies will dance about to entice the female. The most fascinating part is they often are carrying a captured insect,  usually a Bibionid fly, wrapped in silk, as an offering or nuptial gift.

Females seem to prefer a male with the most enticing balloon.  Some males only carry an empty ball of silk.  My guess is they get whoever is leftover.  😉   


These flies and their developing larvae are found in moist wooded habitats (mixed deciduous and coniferous) with many clearings and open patches.  

Larvae are often in decaying vegetation, or even under the bark of trees.  

Adult flies are approx 9-10mm 

 For some fantastic (not mine) photos of the males carrying balloons, check out the bugguide link below.  


References

Alcock , John. 1973. The mating behaviour of Empis barbatoides Melander and Empis poplitea Loew (Diptera: Empididae), Journal of Natural History, 7:4, 411-420, DOI: 10.1080/00222937300770301 

Bugguide. 2023.  Family Empididae – Dance Flies. https://bugguide.net/node/view/6578

Pehling, D. 2004. Empis Dance Flies Empis spp. Bug of the Month . Scarabogram.  https://crawford.tardigrade.net/bugs/BugofMonth40.html

A Minute Scavenger

I found this very tiny (1mm) beetle on the rim of the pool outside yesterday (Dec. 8, 2023). In my investigational efforts to identify my specimen, I have concluded it should be one of the Minute Brown Scavenger Beetles in the family Latridiidae (pronounced la-trid-eye-i-dee). As to species, I think it is Cartodere bifasciata – based on the color pattern of elytra – black markings between 2nd and 5th stria in anteriour third and behind middle; lateral black spot in about middle. (Bugguide, 2014).

This particular species is an Australian native and likely introduced to North America via international shipping. Records show this species in Nova Scotia about 1989 (Majka et al 2009). Looking on iNaturalist for observational reports of this species, I see a few (about 15 or so) in the box I drew. You can see in the attached screenshot the general area where they are turning up in the Western US. Again, likely introduced via international shipping cargo.

Reported observations of Cartodere bifasciata in the PNW Region

Adults of beetles in this family are generally known to feed on the reproductive structures of fungi, plant and animal materials, and slime molds (Evans, 2021). They are found in association with wet or damp habitats in open or forested areas, especially in leaf litter, decomposing wood, on trees, herbaceous vegetation, and in bird, mammalian, or hymenopteran nests (Majka, 2009).

Cartodere bifasciata
Cartodere bifasciata

References and Further Reading

Bugguide 2014. Cartodere bifasciata. Iowa State University. https://bugguide.net/node/view/108526

Evans, A. V. 2021. Beetles of Western North America. Princeton University Press, N.J.

Majka CG, Langor D, Rücker WH. 2009. Latridiidae (Coleoptera) of Atlantic Canada: new records, keys to identification, new synonyms, distribution, and zoogeography. The Canadian Entomologist. 141(4):317-370. doi:10.4039/n09-050.

Grasshoppers in Sin City

Sin City has a new attraction. It’s not the Radio City Rockettes, but they have lots of legs. It’s not a new Cirque du Soleil group, but they can jump and fly through the air with the greatest of ease. This is one animal show that even Siegfried and Roy can’t tame. In fact, most folks (unless you’re an entomologist) would prefer to miss this show when visiting Sin City. Chances are, you are going to get a front row seat whether you want it or not.

The grasshoppers are Las Vegas’ latest and greatest performers. This is NOT the name of a new hip hop, jazz, or rock band either. But there are thousands already performing and more showing up to audition every day. The “invasion” is not the name of a new dance. It’s not the grand opening of a new luxury hotel, but rather the new theme for the whole city. Grasshopper season!

Grasshopper swarm in Las Vegas 2019

https://www.nbcnews.com/news/us-news/grasshopper-swarm-las-vegas-so-large-it-likely-showing-weather-n1035406

This, in fact, reminds me of the crickets that invaded Highland Park Mall in Austin, TX long ago when I worked in the men’s shirts and ties department at Foleys. We had at least a 4 inch layer of crickets that made their way into the first set of entry doors. They had literally piled up on top of one another. Some had gone past the 2nd set of doors and were now in the plastic packaged shirts and the lucite display cubicles. When you tried to pick them out, they squirted out this horribly staining and smelly vomit or fecal matter that made the entire problem so much worse. When mall maintenance workers came around to suck all those crickets in the entry doors up with a vacuum, creating a horrible odor of vacuumed crickets, that did it for me. I didn’t show up for my shift ever again. No notice either. I just couldn’t handle it. (Kinda funny in hindsight that I eventually became a master’s-degreed entomologist). Check out this link to see I’m not exaggerating here one bit! https://www.dallasnews.com/news/from-the-archives/2018/08/14/invaded-crickets-dallasites-battled-swarms-clogged-clocks-plowed-doors

Now I live on San Juan Island. A small, somewhat delightful (unless it’s summertime and the height of a gazillion tourists descending up on us) rural community, accessible by small airplanes or ferry. Last year we had some residents getting pretty worked up by our invasion of praying mantises. I fielded some questions about how they might eat up our hummingbirds. Comments about them ranged from “they’re horribly invasive” to “they’re going to eat all our pollinators.” I smiled and tried to explain as politely as I could how there are only 3 officially documented cases of hummingbirds being captured and eaten by mantises in the United States since the 1800’s, and those were Chinese Mantids, not the smaller European Mantid that is making it’s way west. https://sanjuanislander.com/news-articles/environment-science-whales/environment/28146/revenge-of-the-mantids

As far as pollinators getting eaten by mantids, well, that happens. Everything in nature gets eaten by something. Native species of robber flies and dragonflies eat our cute little bees. So do native spiders and birds. Yes, mantids eat lots of things. Like grasshoppers. That’s why they were introduced to North America in the first place. Which brings me to how I’d like to hand out vintage agricultural reports from the 1930’s and 40’s to some of these panicked individuals and ask them if they’d like to have a few praying mantids on the island or a 6 inch deep layer of grasshoppers! It can happen!

As for those reveling grasshoppers in Sin City…let’s hope what happens in Vegas, stays in Vegas!

More reading:

https://livinghistoryfarm.org/farminginthe30s/pests_02.html https://www.historynet.com/1874-the-year-of-the-locust.htm https://www.nationalguard.mil/News/Article-View/Article/575751/in-1937-colorado-guard-used-flamethrowers-and-explosives-against-plague-of-locu/