Mantis oothecas are fascinating aspects of the praying mantis lifecycle that many people might not know about. They are the protective egg cases created by female praying mantises and are vital for the survival of their offspring. These intriguing structures come in various shapes and sizes depending on the species, such as the Carolina mantis, the Chinese mantis, and the European mantis.
The ootheca serves as a safe haven for the mantis eggs, allowing them to develop and hatch in a secure environment. Inside these egg cases, the mantis nymphs grow and eventually emerge as fully-formed replicas of their adult counterparts, albeit smaller and lacking wings. For instance, the ootheca of the native Carolina mantid is longer and narrower compared to the Chinese mantid.
Knowing more about mantis oothecas and how to identify them not only enriches our understanding of these fascinating creatures, but it’s also beneficial for gardeners who recognize the value of these natural predators in pest control.
Egg Case Formation
Praying mantises lay their eggs in a protective structure called an ootheca. The ootheca is formed when the female secretes a frothy substance that hardens quickly, providing shelter for the developing eggs1. A typical example is the Carolina mantis ootheca, which is small, flat, and resembles a fossilized trilobite2. It is crucial to differentiate between the native Carolina mantid and Chinese mantid ootheca, as the Carolina mantid ootheca is longer and narrower3.
Incubation and Hatching Time
The praying mantis eggs remain within the ootheca throughout the cold seasons and eventually hatch. The incubation period varies depending on the species and environmental conditions. In general, it takes 4 to 8 weeks for the eggs to hatch4. There is a resting phase called diapause that the eggs can undergo, which extends the hatching time into winter break5.
Temperature and Humidity Factors
The successful hatching of praying mantis ootheca is heavily influenced by temperature and humidity. Maintaining these optimal conditions throughout the incubation period is essential for a higher hatch rate8.
Comparison Table (Carolina vs Chinese Mantis)
|Aspect||Carolina Mantis||Chinese Mantis|
|Size||2.5 inches long9||3 – 4 3/8 inches long10|
|Color||Highly variable11 (Gray, Green, Brown)||Brown or Green12|
When the nymphs emerge from their ootheca, they resemble miniature adult mantises13. Initially, they cling onto the ootheca for a short period before leaving to find food and start their independent lives14. It’s crucial to provide newly hatched nymphs with suitable prey and a safe environment to ensure their survival and growth^[15^].
Creating a Suitable Habitat
Choosing an Enclosure
When preparing a habitat for mantis ootheca, consider the size of the enclosure. It should be large enough for the nymphs to move around comfortably while providing ample space for them to grow. Examples of suitable enclosures for mantis nymphs include:
- Glass terrariums
- Plastic critter keepers
- Mesh cages
Adding Substrate and Twigs
To create a more natural environment and help mantis nymphs grip when climbing, add substrate and twigs to the habitat. Some suitable substrates include:
- Coconut fiber
- Orchid bark
- Moistened paper towels
When adding twigs, ensure they are pesticide-free, as this can harm the nymphs.
Maintaining Temperature and Humidity
Mantis nymphs require a suitable temperature and humidity range for their healthy growth and development. Here are some recommendations:
|Temperature Range||Humidity Range|
Use a heat mat or ceramic heat emitter to maintain the required temperature, and mist the enclosure lightly with water to keep the humidity in check.
Light and Ventilation
Proper lighting and ventilation are essential for mantis nymphs. Consider the following:
- Provide a light source such as a low-wattage LED bulb for 12-14 hours per day.
- Ensure the enclosure has proper ventilation to prevent mold issues.
Remember to release the mantis nymphs into your garden once they become adults, as they serve as excellent predators, keeping garden pests under control.
Feeding and Care of Mantis Nymphs
Food Choices for Baby Mantises
Newborn mantis nymphs require an appropriate diet to thrive. Here are some options:
- Fruit flies: a top choice for baby mantises due to their small size and availability
- Small crickets: can be offered to slightly older nymphs as they grow
- Aphids: another small insect option to diversify the diet
Avoiding Cannibalism and Predation
Mantis nymphs are known to be cannibalistic, so it’s crucial to take steps to minimize this behavior:
- Separate newborn nymphs: As soon as they hatch, disperse them into individual containers
- Provide ample food: Keep them well-fed to reduce their chances of resorting to cannibalism
- Use plastic plants: Include plastic plants as hiding places to replicate their natural environment and protect them from predation
Monitoring Growth and Health
To ensure healthy growth and development for your mantis nymphs, pay attention to the following factors:
- Examine their appearance: Use photographs of healthy nymphs as a comparison to spot any abnormalities in size or color
- Check for molting: Shedding their exoskeleton is a key indicator of growth; ensure the molting process goes smoothly
- Observe behavior: Watch for active and normal hunting behaviors; sluggishness or unusual movements may indicate health issues
Comparison of Male and Female Mantis Nymphs:
|Size||Smaller than females||Larger than males|
|Antennae||Longer and more slender||Shorter and slightly thicker|
|Wing Development||More noticeable in later stages||Less wing development|
|Growth Rate||Typically faster||Slower|
Benefits of Praying Mantises
Natural Pest Control
Praying mantises are known as beneficial insects because they prey on various pests. They can be helpful in your garden by controlling small nuisance insects, such as:
They consume these pests and prevent them from damaging plants. Praying mantises also act as a natural alternative to chemical pesticides, reducing the need for harmful substances in your garden.
Contributions to Ecosystem
Praying mantises play a crucial role in maintaining the balance of their ecosystem. They contribute to biodiversity by preying on various species, keeping populations of smaller insects under control. In addition, they provide a food source for other animals like birds, bats, and spiders, contributing to the overall stability of the food web.
Here’s a comparison of praying mantises’ pros and cons as beneficial insects:
|Natural pest control||Can also prey on beneficial insects|
|Help in biodiversity||May not be enough for large pest infestations|
|Reduce chemical pesticide use||Some are invasive species|
In summary, praying mantises offer several benefits as natural predators. They assist in pest control and contribute positively to the ecosystem. However, they might also prey on other beneficial insects and may not suffice for controlling large infestations.
Sexual Cannibalism in Adult Mantises
- Female mantids are known for their sexual cannibalism behavior
- This occurs when the female consumes the male after mating
Sexual cannibalism in female praying mantises is a fascinating aspect of their behavior. After mating, the female praying mantis may devour the male, consuming vital nutrients that help her produce healthier eggs. This is more common in some species than others, and the male mantis has evolved various strategies to avoid being eaten, such as approaching the female cautiously or from behind.
Common Questions and Curiosity
Hatching Time and Procedure
- Praying mantis eggs are enclosed in a protective structure called an ootheca
- They generally hatch in spring after overwintering as eggs
Praying mantis eggs are laid in a frothy substance that hardens into a protective case called an ootheca. This casing provides protection from the elements and predators while the eggs develop. Hatching occurs in spring, and the wingless nymphs emerge from the nest to begin their life cycle.
Interaction with Siblings and Environment
- Upon hatching, mantis nymphs can be cannibalistic towards siblings
- Mantises are found in various colors to blend with their surroundings
Praying mantis nymphs are known to be cannibalistic towards their siblings, especially in the early stages of their development. They are skilled predators, using their front legs and keen eyesight to capture a wide array of prey, such as flies, crickets, and even cockroaches. Mantises can be found in various colors, such as brown, green, or yellow, to blend in with their environment and ambush prey more efficiently.
Caring for Praying Mantis Eggs in Captivity
- Mantis oothecas can be attached to surfaces with double-sided tape
- Regular misting with water may aid in the hatching process
If you have a mantis egg case (ootheca) and wish to care for it in captivity, you can attach the ootheca to a surface using double-sided tape. It is important to ensure the eggs receive proper humidity, which can be achieved by gently misting the ootheca with water. However, it is crucial to avoid over-misting, as overly wet conditions can cause the eggs to rot or develop mold.
How Survival Rates Change Across Different Species
- Tropical species need higher levels of humidity for successful hatching
- North American species are generally more adaptable to varying conditions
Survival rates among praying mantis species can vary, depending on factors such as the specific hatching conditions they require. For example, tropical species typically need higher levels of humidity for successful hatching, while North American species, like the Carolina praying mantis, may be more adaptable to a range of conditions. Always research the specific requirements of the species you are working with to ensure the best possible outcome for hatching and survival.
Over the years, our website, whatsthatbug.com has received hundreds of letters and some interesting images asking us about these insects. Scroll down to have a look at some of them.
Letter 1 – Bug of the Month October 2019: Mantis Ootheca
Subject: Dry husk stuck on rock
Geographic location of the bug: San Luis Obispo, California
Time: 06:33 PM EDT
Your letter to the bugman: Dear Bugman: I found this dry husklike thing on a rock in my front yard. I pulled it off, but didn’t;t learn anything. I know it was once either part of some living thing, or it contained or was shielding something living. Please help!
How you want your letter signed: Yours, Kathy O’Brien
This is the ootheca or egg case of a Preying Mantis, and it does not look like it has hatched yet. Mantids only live a single season, hatching when conditions are right in the late winter or early spring and they mature by autumn. The female Mantis then lays one or more ootheca that will overwinter. If you put this ootheca in a sheltered location, or try to attach it to a branch on a tree or shrub, it might still hatch this spring. Daniel just realized there is no Bug of the Month posting for October 2019, as he neglected to create one at the beginning of the month, so this posting will be tagged as Bug of the Month. Daniel noticed two native Mantis oothecae in the garden in the past week, so perhaps he will take some images and add to this posting.
Update October 15, 2019: Two California Mantis Oothecae in the WTB? garden
When Daniel returned from work yesterday, he made a point of taking images of the two California Mantis oothecae he found over the weekend. Though adult Mantids did not make may late season appearances in the garden, they were obviously hiding quite well as the two oothecae are far enough apart to evidence they were likely laid by two different females.
Letter 2 – Mantid Egg Case or Ootheca
Early in the week we tore down our arbor and fence and discovered this cocoon attached to a fence post behind the foliage. We live near Modesto, CA in the central valley. We have been unable to identify what will come out of this cocoon once the insect immerges – can you help? It is approx. 1 inch long and has scales like a snake. The exterior is very "tough". It has maroon striped markings on each side with a cream color filling out the remaining exterior. My photos are a bit fuzzy – couldn’t get my digital to focus for a closer shot. Any assistance you can provide would be appreciated! My children and I are perplexed.
I would like to do more research before giving you a definite answer, but it looks more like an egg case than a cocoon. It might be a preying mantis egg case known as an Ootheca. I will get back to you.
Thank you – as you can see, I’m not up on bug terminology. A mantis would be wonderful.
Letter 3 – Mantis Ootheca
Subject: Egg pod identification
Location: Humboldt County, California
February 1, 2015 9:15 am
We found this on the underside of a branch on our dogwood. My guess is praying mantis. Husbands guess is some type of moth. Any ideas?
Signature: Clueless in California
Dear [Less Than] Clueless in California,
Your guess that is is the Ootheca of a Preying Mantis is correct.
Letter 4 – Mantis Ootheca
Subject: Hard Shell Mystery
Location: Silver Lake (Los Angeles)
May 24, 2015 4:39 pm
A neighbor noticed this disturbingly large hard shelled , something on my fence this afternoon. About 2 1/2″ long, 3/4″ wide , 1/3″ deep. A pupae perhaps? The neighbor poked w/ a stick & it fell off (although it was stuck to the fence quite well), and we lost it in the leaf matter. There’s something very prehistoric about it. Never seen anything like it before.
Signature: Diane E
This is the Ootheca or Egg Case of a Mantis, and we believe it might be that of a native California Mantis based on these images on BugGuide. It looks to us like the Ootheca has hatched, likely releasing several hundred tiny Mantids.
Letter 5 – Mantis Ootheca
Subject: Strange Arthropod
Location: El Paso, TX, USA
July 30, 2015 3:14 pm
Hello Mr. Bugman,
My mother sent me picture and asked if I knew what kind of “bug” it was. She was pretty creeped out, since it looks so wild and crawls all over the outside of her house, but so far has not strayed far from that location. For the life of me, I couldn’t think of anything that looks like this besides Cambrian era arthropods (haha), so I was hoping I may have luck with you. If not, don’t worry about it!
This looks like the Ootheca or Egg Case of a Preying Mantis, and it also appears that it has already “hatched” releasing several hundred tiny, predatory Mantises into your mother’s yard where they will help to control insect populations.
Letter 6 – Mantis Ootheca
Subject: Larva ? attached to a fallen twig
Location: West Los Angeles yard
January 9, 2016 6:11 pm
This is a gray, silver striped, scaley, fattish (3.3 cm by 1.1 cm), thing is tapered at both ends and is stuck fast to a twig from a Kolreuteria bipinata (Chinese golden rain) tree. The exterior is hard and doesn’t respond to light touch.
Signature: Fran Andersen
This is an ootheca or egg case of a native Preying Mantis in the genus Stagmomantis. Many nurseries sell mantis oothecae to appeal to ecologically conscious gardeners, however, they are generally the oothecae of non-native species that will also prey upon smaller native Mantids.
Wow, thank you. So you guys are sometimes quicker than you warn us to expect. I was prepared to be patient. Now I have patience to burn.
Nice going Daniel. You are good.
Letter 7 – Mantis Ootheca
Subject: My neighbor found this on her fence.
Location: 45° 30′ 34″N 122° 30′ 28″W
April 4, 2016 10:40 am
Im trying to identify a “cacoon like” structure on my neighbors fence i currently have only a picture go by. I would say a moth cacoon off first glance but the striations throw me off a bit. Please help me in figuring if this needs to be gotten rid of or left alone.
Signature: Jeff Homsley
This mantis ootheca will hatch several hundred beneficial predators.
Thank you sooo much…thats incredible
Update: April 6, 2016
Though we originally responded to this request, we did not create a posting. Since posting our own images of a California Mantis hatchling and the ootheca from which it emerged, we decided to turn this submission into a bit of a public service message for home gardeners. It is frequently necessary to prune plants in the garden, but it is always a good idea to look closely to see if there are any beneficial critters, possibly in the form of immobile eggs or pupae, in the trimmings. We make it a habit to toss branches into the green bin, but to leave the lid open in the event that anything needs to escape. Just last summer, while trimming the guajes, we found two California Mantids, so we relocated them elsewhere in the garden. We encountered more Mantids last year than any other year, and we credit that to becoming more aware while cleaning up the yard. About a month ago, we removed a broken branch from the butterfly bush and found three California Mantis oothecae, so we tied them securely to other plants, and we have now been rewarded with a sighting of a hatchling Mantis. The ootheca in this image looks to be a native species in the genus Stagmomantis. According to the 4H pdf, the California Mantis is reported from Oregon. Though we are in favor of organic gardening, we like to caution our readers about the potential problems of purchasing commercially available Mantis oothecae from dealers as those are generally not native, and introducing non-native predators can have a negative effect on native species. Non-native Mantids are larger and more aggressive than our native species, and we suspect our natives are being eaten by Chinese and European Mantids.
Letter 8 – Mantis Ootheca
Subject: Hard cocoon on chain link fence
May 18, 2016 3:55 pm
Hi bug man, I spotted this cocoon on the chain link fence in our backyard. I’ve tried Googling with no luck, and I’ve become very curious about it. It’s very hard. It’s currently late spring here, in the north Eastern United States.
This is the Ootheca or Egg Case of a Preying Mantis, and you can expect several hundred hatchlings this spring.
Letter 9 – Mantis Ootheca
Location: Southeast Pennsylvania
March 25, 2017 9:16 am
We found this on a knock out rose bush, that came with a home we just bought. We did find evidence of rose cane borers, but this doesn’t appear to be related. Did some searching for chrysalis and cocoons online, but they all see so much prettier than this.
This is the ootheca or egg case of a Preying Mantis. When the weather warms, several hundred hatchlings should emerge. Mantids are predators that will help keep unwanted insects from your plants without the use of pesticides.
Letter 10 – Mantis Ootheca
Subject: Tre killing Weirdo Thing?
Geographic location of the bug: Los Angeles, CA
Time: 09:49 AM EDT
Your letter to the bugman: Hello sir,
This weirdo cocoon(?) is on our Silver Sheen Pittosporum tree. We’ve been puzzled about it for a few months now. I woke up this morning thinking about it, I’m concerned that it might be harmful to the tree, as four of these trees have mysteriously died in the past year. Is this the culprit?
Thank you for your time!
How you want your letter signed: No, thank you.
This is the ootheca or egg case of a Preying Mantis and it is not responsible for the death of your trees. Mantids are predators that are often used by organic gardeners to control insect pests without the use of pesticides.
Your original request arrived when our editorial staff was on holiday and we never seem to catch up on requests when we are away from the office. We do not believe native California Mantids are a threat to either your Monarch or Gulf Fritillary Caterpillars, but Mantids will eat pollinating insects including Bees.
Letter 11 – Mantis Ootheca from Australia
Subject: Unusual nest?
Location: Childers, Queensland Australia
February 14, 2015 4:46 am
I was hoping that you would be able to tell me what insect this ‘nest’ might be from. I found it attached to my Queensland Lace Tree and I am intrigued by the intricacy and the absolute neatness of the weave, to me it is a masterpiece of engineering, it looks and feels like a ‘loofah’.
Any help would be very much appreciated
Signature: Cheers, Dianima
We are quite certain this is the Ootheca or Egg Case of a Mantis.
Letter 12 – Mantis Ootheca found on husband’s undies in Australia
Subject: What is responsible for this?
Location: Canberra, Australia
March 10, 2016 2:40 am
This is probably an incredibly easy question as I myself have seen many of these before, but I have a conundrum. This appeared on an essential item of clothing (my husband’s undies) hung out to dry and I am loath to injure whatever creature may be in it by scraping it off. I realised that despite seeing these things a lot I have no idea what makes them, and trying to dentify things via the Internet when you don’t have the actual creature appears near impossible! Are you able to tell me what it is? Thanks very much for your time!
This is the Ootheca or Egg Case of a Preying Mantis, and we are not familiar enough with Australian species to provide you with an exact identification, however, if you see Mantids in your yard and garden, and you submit an image of one of them, we will attempt a species identification. Here is a very similar looking Ootheca of a Garden Mantis from Oz Animals. The Ootheca is formed of a frothy substance produced by the female to help protect the eggs inside. When conditions are right, you can expect several hundred hatchlings to emerge. In our opinion, you should hang your husband’s undies with the attached ootheca in a protected place in the garden, preferably on a low shrub, and let nature take its course. As our editorial staff will be away for a few days, we have postdated your submission to go live over the weekend while we are away.
Thank you very much! I did not expect such a quick reply and I really appreciate it! I will most certainly be doing what you say, and my husband is willing to sacrifice his undies to give the little mantids the best chance at life.
Because of your kindness and because of the tremendous sacrifice your husband is making, we are awarding you as a couple the Bug Humanitarian tag on this posting, though you still have to wait until March 13 to see your posting live.
Letter 13 – Mantis Ootheca from New Zealand
Subject: Interesting Structure on Tree Trunk
Location: Shipton Reserve, New Zealand
October 2, 2016 2:13 pm
I found this interesting looking structure attached to a tree trunk. Would you be able to identify it for me?
This is the ootheca or egg case of a Preying Mantis. We located similar looking images on Friends of Te Henui and on T.E.R:R.A.I.N where it the species is identified as Orthodera novaezealandiae and the following information is posted: “They lay eggs in foamy egg case called an ootheca. The ootheca has a woody appearance and has straight uniformed sides. They are usually attached to a leaf, stem, wall or fence. The young hatch out as small versions of the adult.”
Letter 14 – Mantis Oothecae
Location: Aurora, CO
April 7, 2015 2:43 pm
Found this on my bottle tree, so not on growing wood.
Each Mantis Ootheca should hatch into several hundred hungry baby Mantids. We wonder if they are a native or an introduced species. Introduced Mantids from Europe and China are larger and more aggressive than native Mantids and they may be responsible for dwindling numbers of native species.
Letter 15 – Mantis Ootheca
Subject: Praying Mantis Ootheca?
Location: Southeast AR
October 23, 2012 12:00 am
Found this on the side of my house and not sure what it is. I’m thinking it’s a Praying Mantis Ootheca but am not sure.
Signature: Christine R.
You are correct. This is the ootheca or egg case of a Preying Mantis.
Letter 16 – Mantis Ootheca
Subject: Cacoon identifacation
Location: Ypsilanti MI
February 16, 2013 7:23 pm
Hi I live in lower southeast Michigan and am moving and see a few of these hanging in my backyard, Im wondering if you can help me figure out what may be hatching from them. Im a photographer and dont wanna miss it when they hatch, can I move them into my garage? Im thinking a big moth is what it may be :))
Signature: Rachel R
This is not a cocoon. It is the ootheca or egg case of a Preying Mantis and it will “hatch” into several hundred young mantids. If you get a photo of the hatching, please send us one for posting. Don’t keep them in a place that is too warm or they will hatch prematurely.
Ohh cool I love praying mantis too, I will leave them be till It warms up then :)) Thanks so much for the info I was reallyy wondering what they were :)) Also glad that went thru, after I typed it I saw it said wouldnt work w iphones, but it didd 😀
Letter 17 – Mantis Ootheca
Subject: Can you identify this tree borer by the egg sack?
January 27, 2014 11:06 am
Hello, I recently took a new job as a groundskeeper after many years doing landscape work. This property has a tree borer that I haven’t identified before. Can you help me identify it by the egg sack? Picture attached.
Thank you so much!
While we are not disputing that you may have some type of borer on the grounds, both of the images you have attached are of Oothecae or Egg Cases of Preying Mantids, and by all accounts, they are considered beneficial predators.
Cool! That’s actually really good to hear. I have over 50 sugar maples that look like they have been shot with buckshot. It’s nice to know Mother Nature is trying to fix the situation for me!
Thank you vey much! I appreciate your time
Hi again Nick,
Should you happen to get a photo of the Borer, we would glady give a try at identifying it for you.
Letter 18 – Mantis Ootheca saved from the flames
Look what almost burned up with the dead perennials!
Location: Naperville, IL
November 7, 2011 1:47 pm
I am sad that bug season is coming to an end here in Illinois, but at least I can continue to see all the wonderful specimens from more temperate climes, thanks to your web site. It is the time of year when I cut down my dead perennials and prune back some shrubs, most of which end up on my burn pile. I always come across a handful of mantis egg cases in the process, and this one was inches away from the flames when I noticed it. It’s attached to a yew branch, and I also have them this fall on a lilac stem, a raspberry cane and a wire garden fence. I’ve yet to find any on an actual dead perennial, which makes me wonder if the female mantis knows the difference. Have a lovely week!
Signature: -Dori Eldridge
We are happy to hear that this Mantis Ootheca or egg case was spared the flames because you found it before it was tossed onto the bonfire.
Letter 19 – Mating Mantids and Ootheca production
Subject: Mantis Love
Location: SW Ohio
September 7, 2013 4:40 pm
Yesterday, I sent you a picture of a mantis depositing an ootheca behind the butterfly bushes. Well, as I said, it’s a happening spot. Here’s some mantis-love.
Subject: Mantis in the act of depositing ootheca
Location: SW Ohio
September 6, 2013 7:08 pm
My butterfly bushes are popular with mantids, and the warm brick behind them serves as a handy Labor and Delivery ward for them this time of year.
Normally they just seem to spring into existence, but I was very lucky today to stumble upon this small mantis in the act of depositing one. I was really excited and tried to watch as closely as I could without stressing her out too much (she did swivel her head to keep an eye on me when I got too close).
Here’s a picture, taken with the regrettably grainy camera on my phone. It was all I had with me.
Thanks for sending both of your images and the wonderful descriptions. The butterfly bush has obviously become an important contributing factor to the Preying Mantis population in your garden.
Letter 20 – Mating Mantids and resulting Egg Case
Is this a good bug or bad bug?
We have Praying Mantis’ in our yard here in Rocklin (Sacramento) CA. Shortly after seeing they are getting ready for the winter we see this Cocoon or Crysalis (which is it?). Are these the eggs for the good bug, Praying Mantis, or do I need to get rid of these if they’re a bad bug? Or, thirdly, are these good eggs for some other bug? Thanks for the insight and help as we decide to keep or eliminate this addition to the house this winter!
Larry in Rocklin CA.
We love your mating Mantis photo. The result of the coupling is the subject of your second photo, a Preying Mantis Egg Case. The female spews out a frothy substance with her eggs that hardens to protect them from inclement weather. Come spring, you will have 100’s of baby Mantids emerging to rid your garden of unwanted, and occasionally beneficial, insects.
Letter 21 – Mystery Thing from Australia: Mantis Ootheca?
Subject: aussietrev strange egg sac?
Location: Queensland, Australia
February 3, 2014 9:21 pm
Here is the strange object I found on the back of a cucumber leaf in my yard. I assume it is an egg sac, and it has the extruded foam sort of texture of a mantis but it doesn’t look like any that I have ever seen before. Any ideas guys?
Our first thought, prior to reading what you wrote, was that this mystery object looks like extruded foam and that led us to contemplating the possibility that this might be some odd Mantis Ootheca, so we are in agreement with what it seems most like. It also appears that whatever this mystery object might have held has gone, possibly by hatching. How large was it? Alas, all the images on The Insect Store mantis ootheca identification guide do not appear to be showing at this time. We also just realized that for years we have been spelling the word Ootheca with an “i” and we will need to contact our webmaster to see if he can do a site fix on that error. Another possibility is that this might be a Cockroach ootheca. Hopefully, we will soon find an answer.
The thing is about an inch overall. It has similarities to a bark mantis Ootheca but the pictures on Brisbane Insects are of still closed one making it a bit harder to compare. They also appear to be flat against the trunks where as this one has a crescent moon type shape. Given the number of suitable trees nearby I would think it unlikely that a bark mantis would suddenly change to greenery and lose the camouflage advantage for its young though.
Letter 22 – Young Mantids
Subject: Young Mantids
Geographic location of the bug: Campbell, Ohio
Time: 6:05 PM EDT
Last November, while in Ohio, Daniel cleared some brush from his mother’s garden, and he discovered several Mantis oothecae on twigs and other places, including this tomato cage. Daniel moved the tomato cage with the attached ootheca closer to the house where his mother grows potted plants each year.
Earlier in July, Daniel’ mother informed him she saw two Mantids among her petunias and the other potted plants, and when Daniel arrived late in July, they were still there, very well camouflaged and prowling among the blossoms.