I hope this doesn’t break the ‘help with id’ forum rule - it’s not intended to directly elicit identification, rather a suitable identifier. I’m actually hoping to be directed to an entomologist with expertise in cockroach id. https://www.inaturalist.org/observations/45120497
I posted this back in May and it got some interest but no id. I also sent it to the Australian Museum and received this reply:
> Hi Condell
*> * > Thank you for your enquiry.
*> * > I couldn’t find a match and sent it to a number of entomologists. This was their reply “It’s not often we can’t identify a cockroach; nothing in our collection is close to it and David Rentz doesn’t know it. Any chance that it was collected so we can have a closer look at it?”
*> * > So if you see it again, and are able to capture it, our entomologists would love to have a closer look it . > > David Bock
*> * > Manager, Search & Discover | Visitor Experience and Education
*> * > Australian Museum 1 William Street Sydney NSW 2010 Australia
Before I get excited about a possible new species I would like to have more expert input, so if you’re aware of an entomologist with appropriate interest/expertise could you please let me know. In the event that it can’t be identified (I think the likelihood of capture rather small) what next or is that the end of the story?
I’d say that is a pretty exciting response you received, and about as expert as you are going to find, on or off of iNaturalist.
But that said, in general I use Explore to bring up a taxon in a given region of the world, look at the ID leaderboard, and check user profiles of some of the leaders to see who else might have particular expertise for that taxon.
In the Filters on the resulting display, you’ll see the inputs that generated this URL.
Looks like the top identifier has already weighed in on your observation, so again, you may have the most expertise possible already. But definitely not the end of the story – just the beginning! I would keep communicating with these experts, make sure your location data etc. is as accurate as possible, and even if you are not able to revisit the location for a specimen, hopefully someone else will be motivated to. I’ve had personal experience with plant species new to science here on iNaturalist, and while they have to sit at a higher-level ID until the species gets named, having the information here is super valuable. Good luck with this one!
Thank you so much for your kind reply and excellent suggestions, Jim - all good avenues.
An anecdote about the observation - was going to light the ‘incinerator’ outside just after the fire bans ended for the year and thought to take my camera in case anything living emerged (thinking maybe snakes, skinks). As the smoke started the cockroach appeared and wandered about on the bricks for just long enough - most serendipitous. So there is the opportunity to partially recreate the scene.
I do appreciate the encouragement :)
I agree, this sounds like just the beginning to me. There are a few possible outcomes, but it sounds like keeping in touch with the Australian Museum and their entomologists will be productive whatever the outcome. For reference, the David Rentz they looped in should be this David Rentz, so appears to be quite well-versed in the group. You can, of course, seek out other experts, and there appear to be a few who use iNat as noted above. Here are some of the possible outcomes:
One of the first possibilities is that it ends up being something already known to science. Entomologists with a specimen in hand will be able to run through existing keys and compare to museum specimens. Sometimes, differences in color will end up being a part of the variation of a known species. It may still end up resulting in a paper being written even if it’s just a color variation. Or, it may end up being that there’s one of those obscure specimens within the collection that it aligns with perfectly or an introduced species that wasn’t originally considered.
Another possibility is that it indeed is a species new to science. Running through keys may show some distinct structural differences not immediately noticeable in the photos and give validation for it as such. It can take a while for everything to be official, but it’s certainly well worth it.
Yet another possibility to consider is that it cannot be determined at this point. Maybe there’s a reference in the older literature to a species that isn’t among the existing museum specimens that requires further investigation. Or it could be that additional genetic tests need to be done. This just means it may be a while until there’s a final answer, but it’ll be somewhere in the system in the least.
But, of course, the only way to know one way or another may be through finding a specimen. I certainly wish you well in another chance encounter!
Thank you for your detailed and thoughtful response, Jonathan. You clarify possible outcomes very well. I am greatly encouraged by the responses to this post and will take this advice forward - beginning with some attempts to smoke out the elusive roach. Thank you all.
I don’t really have much more to add except this. All of the cockroaches mentioned in the links are all in western Australia. The museum is in Eastern Australia. Is there a university or museum in Adelaide that may offer help? The reason I’m suggesting this that western Canadian Noctuid moths are not the same as eastern Canadian moths. I don’t know if it’s the same in Australia or not, but it might be worth it to check for any resources in your region.
BTW, I stuck David Rentz’s name into Google Scholar, and he has published a book on the cockroaches of Australia (https://books.google.ca/books?hl=en&lr=&id=uvynAwAAQBAJ&oi=fnd&pg=PP1&dq=David+Rentz&ots=KKnn19aVtO&sig=AtwZpQZ0-c5nCflWLoK0cwBbWJw#v=onepage&q=David%20Rentz&f=false). If you are interested in leaning more about that group it may be worth getting hold of a copy through a library. It may also be a link to further resources.
Hello Ian - many thanks for your useful suggestions - there is a museum in South Australia that I’ve utilised for information and ids previously (to the point where they suggested my joining iNat lol). Yes, David Rentz does seem to be a leading authority on cockroaches here. Appreciate your thoughts on this.
An update - I have caught one. It was inside the house. I’ve emailed David Bock of the Australian Museum as it was he who encouraged me to try and catch one (see previous post). My question is, should I euthanise it now (freezer?) or is there any chance the Museum would want it live?
I am tempted to do the former, but it’s the path of no return…
hope you can offer some advice, please
I suspect that there is no other way to get it there except by killing it. I know next to nothing about cockroaches, but freezing it would kill it, and immersion in alcohol would preserve the soft tissues. J.E.H Martin (http://publications.gc.ca/collections/collection_2016/aac-aafc/agrhist/A42-42-1977-1-eng.pdf) suggests treating Blattoidea in the same manner as Orthoptera (p. 137). This is a great reference book for collecting and preserving insects.
A more direct approach would be to contact the people involved and see how they would like it sent. Keep the insect in the fridge until they reply.
For insect preservation you usually use 70% alcohol, 30% water. But that spoils it for DNA extraction, so it might be worth taking off a non-fleshy part such as a foot and drying it so the DNA can be got at.
Have entered this info on obs page but, in case you missed it, here is the rather anticlimactic result.
From the Australian Museum:
‘The specimen you sent has been examined and the native cockroach has been identified as a juvenile Platyzosteria similis Common name Red-legged litter runner.’
There have been comments around the apparent anomalies with winged/not winged and juvenile/adult - I have not a clue and have pressed museum for some detail but I fear this may come to a dead end. Thank you for your research, suggestions and support - much appreciated.