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Greenhouse camel crickets (Tachycines asynamorus)

Here are some photographs of greenhouse camel crickets (Tachycines asynamorus) that I recently found around my house. I gather the common name was applied when it (and related T. japanica) first came to Europe from Asia and took up residence in conservatories. I’m not positive, but I think before that invasion the name “camel cricket” was commonly applied to the praying mantis (I have no idea why but perhaps because mantises are very heat tolerant).

For annoyed taxonomists: Latin name used to be Diestrammena asynamora but is now Tachycines asynamorus for reasons that are beyond me but are apparently explained in Qin et al. 2018. Nobody seems to use the new name except iNaturalist. But I use iNaturalist a lot so I’m going to give the new name a try.

Juvenile greenhouse camel cricket (Tachycines asynamorus) in bathroom sink

This is a juvenile that I found in my bathroom sink. I think they go through 10 instars and I’m guessing this is a 3rd instar male (lacks an ovipositor). It was pretty cute.

Female greenhouse camel cricket (Tachycines asynamorus) in cat litter

Camel crickets love to eat cat feces (don’t judge) so it’s pretty common to find them lurking here, sometimes in large groups. I don’t think the females lay eggs in cat litter but I’ve always been curious. Not curious enough to examine more closely, though.

Female greenhouse camel cricket (Tachycines asynamorus) in cat litter

This is the same individual as above but shows the ovipositor and impressive length of the antennae. The antennae apparently have the ability to sense heat. That’s probably a fact most people don’t want to know.

Female greenhouse camel cricket (Tachycines asynamorus) on stacked firewood

This female was in the woodpile near my garage. It was a cold day so she didn’t immediately launch herself away. They often seem to jump at you, a behavior that doesn’t endear them to folks who think the crickets are actually spiders. I think their jump can max out at 1 1/2 meters, which is pretty impressive. They can’t fly, though, because they lack wings (and are thus silent). Note that placing woodpiles near your house is one way people inadvertently introduce camel crickets into their houses.

Greenhouse camel cricket (Tachycines asynamorus) frass on wall

These three gooey splotches are frass. If you have a large population of camel crickets your wall will become darkened with this spots. I’ve been trying to figure out why they are liquid but haven’t come up with any explanations yet.

If you’re fascinated by greenhouse camel crickets there’s a great article at Your Wild Life that describes how different species are invading the United States. If you just want to kill them I have a few ideas.

DIY trap to kill pregnant mosquitoes

This post contains photographs and construction tips for a killer craft I made: an autocidal gravid ovitrap. Pregnant females enter the trap, lay some eggs on or near the stagnant water within, then are prevented from exiting and die. Their progeny also die because a screen at water level prevents larvae from reaching the surface to obtain oxygen. When similar traps have been deployed they bring down mosquito levels substantially and thus are quickly becoming one of the main ways to prevent mosquito outbreaks and disease. Every homeowner should have six. They’d make wonderful gifts.

Autocidal gravid ovitrapThe design features a clear dome that helps trap the females when they are done ovipositing (they go for the light), plus a completely unneeded observation window so I can watch the larvae and pupae (fun for the whole family, plus good for demonstration purposes). It borrows general methodology from gravid Aedes traps (GATs) designed by Dr Scott Richie (James Cook University) and colleagues that recently made news on NPR (here’s an overview; here’s their paywalled journal article). I’ve designed mine to capture species that also lay egg rafts, so it’s not just a GAT. My design doesn’t use insecticide because I wanted the odor of developing larvae to be an attractant to other females (it is, by the way).

What you need

  • Autocidal gravid ovitrap2-gallon bucket
  • bucket lid
  • 6″ plastic pot
  • clear dome from cake store
  • metal coat hanger
  • plastic screening
  • stapler
  • 3 paperclips
  • small neodymium magnet
  • silicone adhesive glue
  • duck tape
  • hardware cloth
  • 1-L soda bottle
  • 1/4″ foam weatherstripping
  • black spray paint
  • Dremel tool with cutting bit
  • drill with drill bit
  • knife
  • safety glasses (when Dremeling)

Construction photographs

If you’d like to see photographs larger just click on first image and navigate like a slide show. There are many ways to construct these so if you build one and it looks completely different, don’t worry. This is because if your device is the only stagnant water around, females will use it.

I’ve only just deployed it and it’s rather cold right now so I don’t have any victims yet. But I’m optimistic and am posting now with the hope that somebody will have suggestions on how to improve the design (I’m making more). One improvement I’m definitely going to make is to drop the funnel lower into the dome so it’s harder for females to accidentally fly straight up to escape. And pro-tip if you make the above: attach the lid to pail when spray painting to avoid unwanted buildup where they attach.

I’m also posting in the off chance that a biology teacher might take an interest. Having teams make these would be really fun and then they could deploy them in the woods near the school: bonus points for team that traps the most mosquitoes. It’s fun like the classic egg-drop lab in physics except useful. Students would then take their projects home where they’d continue to be useful. Would make for a great Girl Scout Gold Award / Eagle Scout project.

Other DIY designs

For ways to kill foraging mosquitoes, please see my page, “Mosquito control tips“.

Where to buy

If all of the above sounds like way too much work you can buy traps from SpringstarBioQuip, and Ultimate Mosquito Traps. I haven’t tried any of these yet.

Useful articles

Barrera, R., A.J. Mackay, and M. Amador. 2013. A novel autocidal ovitrap for the surveillance and control of Aedes aegyptiJournal of the American Mosquito Control Association, 29:293-296.

Maciel-de-Freitas R., R.C. Peres, F. Alves, M.B. Brandolini. 2008. Mosquito traps designed to capture Aedes aegypti (Diptera: Culicidae) females: preliminary comparison of Adultrap, MosquiTRAP and backpack aspirator efficiency in a dengue-endemic area of Brazil. Mem Inst Oswaldo Cruz. 103: 602-605.

Mackay, A.J., M. Amador, and R. Barrera. 2013. An improved autocidal gravid ovitrap for the control and surveillance of Aedes aegypti. Parasites and Vectors 6:225.

Maire, A. 1985. Effect of axenic larvae on the oviposition site selection by Aedes atropalpus. J. Am. Mosq. Control Assoc. 1:320-323.

Paz-Soldan et. al. 2016 Design and testing of novel lethal ovitrap to reduce populations of Aedes mosquitoes: community-based participatory research between industry, academia and communities in Peru and Thailand. PLoS One 11:8.