New Mantis Alert!

Guess what everyone, I have wonderful news! As of today, I've just published my first new species - not one but TWO very cute little mantises, and one was discovered right here on iNat! You can check out the paper here.

If you know where to look, the Paperbark Mantis (Ima fusca) is one of the most common mantis species around Cairns. There can be numerous individuals in just a tiny patch of trees, and they often live right in suburbia. Despite this though, rarely anyone ever sees them! Why?? Well, it's quite simple really. Ima are small, cryptic, and they pretty much only live on paperbark trees (as the name suggests). So in general, you're unlikely to see one unless you're specifically looking for it.

Now this was actually quite the problem for me - part of my Honours project last year focused on these little mantises, with the aim of giving them a modern taxonomic treatment. But of course, a taxonomic revision is difficult if nobody collects any specimens for you! Luckily for me, male Ima do come to lights at night, so I still had plenty of specimens to work with, although of course the vast majority were males (that's okay though, because as we will see males are much more identifiable than females).

Because Ima aren't generally encountered much, it was actually quite difficult for me to work out where I needed to go to find them (especially before I started looking at any museum specimens). Have a look at the map of iNat sightings prior to mid-2019:

This little area around Cairns was the entirety of their known distribution to anyone who didn't have access to museum specimens. The holotype is from Cairns as well, so maybe this really was the only spot they were found. But of course, as we now know, they are much more widespread! My first indication of this actually came way back in 2018, when I photographed a juvenile Ima aaaall the way down south at White Mountains NP near Charters Towers. And then a few years later, @domf spotted some Ima up in Weipa! So far from a measly ~90km, the actual range of Ima extends well over 900km!

Since then we've been filling in a couple of the gaps here on iNat, and of course there are museum specimens from across this range. Here's what our current iNat map looks like:

Still lots of empty space with no records, but we can at least get a general idea of where they're found.

Now the key question that comes from all of these records is this: Are these all Ima fusca, or are there other species of Ima hiding in plain sight?? This was a key question that I worked on for quite a while last year. Initially, I suspected that there might be three different species - one in the north, one in the middle, and one in the south, or that perhaps the middle population was the same as one of the other two, and hence that there were two different species.

Here's @shesgotlegs's photo of the wonderful new Ima corymba:

The actual result was in fact quite a bit stranger than I was expecting! There were two different species, one in the north, and one in the south. But in the middle, both species were present! Around the Wet Tropics, both Ima fusca and the newly-named Ima corymbia are present and widespread. However, they always seem to occur in different habitats, and I am yet to find any one spot that has both species. Ima fusca prefers the wetter areas along the coast, and Ima corymbia prefers the drier inland areas. North of Cooktown, only Ima fusca is present, and south of Caitns it is only Ima corymbia (mostly).

This difference in distribution is really helpful, because unfortunately for us the two species simply cannot be identified from photographs. The only difference between them is the structure of the male genitalia! There are numerous insect species that can only be identified from genitalia, and unfortunately this is one of them. But no matter! They're super cool, even if we can only identify them to genus most of the time.

So Ima corymbia is one of our new mantis species, but what about the other one? Well, this second one is arguably even cooler, because it was discovered right here on iNat!

Let's welcome to the world the wonderful little Inimia nat, or I. nat for short. See what I did there? 😂 We have @reiasai97 to thank for that excellent pun! Here's an excellent photo of the holotype from Brendan James:

I. nat was first spotted here on iNat by @glendawalter in May last year. As soon as I saw it I knew that it was something unusual, and I initially thought that it was an odd species of Ima. After Glenda sent me some specimens, however, it became clear that this was something stranger - more like a cross between Ima and Calofulcinia. And our (as yet unpublished) genetic results do suggest that it is closer to Calofulcinia than Ima, so what that meant was that we had not just a new species but an entirely new genus!

For me, the most exciting part of this new discovery is that it shows just how fantastic iNaturalist can be as a tool for taxonomic research. From the day Glenda first posted I. nat on iNat, it took less than a month for the appropriate experts (i.e. me) to see it, realise it was something interesting, and receive some specimens to work with. The actual writing up and publishing part of course took a bit longer, but the speed with which this initial discovery and collection took place is just astonishing.

We now have a number of I. nat specimens to work with that will all be lodged in museum collections, including not just adult males and females but juveniles of both sexes and oothecae. So thanks to iNat, we now have almost the entire life cycle of this mantis documented. In fact, only a single specimen exists that wasn't collected with the help of citizen science - a very old male from Rockhampton that's in quite poor condition. It was labelled as Ima, and without iNat we may never have even known about the existence of this remarkable little mantis.

I feel like I'm probably preaching to the converted here, but the discovery of I. nat perfectly illustrates just why iNat is so great. From the perspective of the observer, how cool is it that you can just go outside and find a completely new species?? Here in Australia we just have so many undescribed species that it's actually really easy to find new ones - the problem instead is that it's hard to work out what's new and what's not unless you're an expert. iNat is a way to connect you with those experts who can tell you exactly what you've found.

And from the perspective of the researchers like myself, it's amazing to have thousands of pairs of eyes out looking for cool new species! Sure, in some groups it's hard to work out whether something is new or not from photos alone - just look at the case of Ima fusca and Ima corymbia above. But every now and then something unique will show up, like I. nat, and then it's as easy as pie.

That's the best part of iNat for me - it connects taxonomists (and other researchers) with the interested amateurs who can use and appreciate their research. Taxonomy is a bit of a dying art these days, but maybe this sort of thing is exactly what we need to kickstart a new taxonomic revolution!

And once more, you can read the full paper here (if you don't have access, message me and I'll send you a copy).

And I did another short writeup here if you want to have a read!

Posted on November 30, 2023 10:32 PM by matthew_connors