The Pacific Beetle Roach
In December 2020, I received the last of the new cockroach species of the year. Diploptera cf. puntacta also known as the Pacific Beetle (Mimic) Roach, because the cockroaches once they reach adulthood look just like beetles.
Diploptera puntacta - nymph
Diploptera puntacta - nymph
Quite excited for this species and to see them as adults. I really love when roaches mimic other insects!
First things I have noticed:
1 - the musky smell inside the box. Not sure if the smell is from the release of any defensive chemicals from the shaking of the box during transportation or if this is their "natural" smell.
2 - their speed and ability to climb walls... bloody hell... i wasn't expecting that for small nymphs. They are quite bold. Normally other nymphs will quickly run under the leaves or substrate to hide after being exposed. Well not these ones! After being re-house, and without warning they all started climbing the walls and trying to escape!
All Hell was set loose in less than one minute!
There is a reason though, in particular for this genus, they are said to be quite bold.
In most insect species, juveniles and larvae are less mobile than adults and, due to their smaller size, they are at risk from a much wider range of predators; they therefore experience higher predation pressures, influencing both boldness and predator escape performance.
Their smaller size also imposes restrictions on the time they can spend without foraging, which may in turn promote bolder behavior; their greater metabolic requirements may be linked to a greater propensity to take risks, as such juveniles are significantly bolder than adults, most likely due to differences in the ecological requirements of these life stages.
3 - Very difficult to photograph! Exposed to the open, they keep running and running endlessly... the only chances I had was when i would touch their antennae and the oils in my hand would bother their senses... they would stop and lick the antennae for few seconds and then start running again. You can see in one of the photos, the nymphs cleaning itself up.
One interesting fact I noticed during my photographic sessions with the nymphs, is that they appear to lift their tarsal claws (and another structure which I don’t know the name or function) while running.
Nymph with its tarsal claws lifted
At least they do this on flat surfaces, I am not sure if those are the adhesive pads used for climbing, which would make sense, as they need to lift them up to avoid getting stuck to the surface while running.
During this month of keeping, I have noticed two more things:
4 - Comparatively to other species I keep, these seem to be the most heat seeking roaches I am keeping. There is only one more that displays similar behavior, but not so fast and not so widespread as these guys, which are the Dubia roaches. Because the temperatures in my region have dropped significantly since the end of December, every time I turn on the heater in the Insect Room, these roaches immediately congregate on the glass closer to the area where the heater is. They pick it up so fast! its amazing!
Roaches congregating to bask on the warmth from the heater
5 - Also this last month, although they don’t tend to show themselves out too much especially day time, I know they have been feeding well because the food is constantly disappearing… and they molted once! yeay!
The amazing part was that they molted once and all in sync!
I almost had a heart attack at first sight! I thought they were all dead initially!
Molts hanging on the sides of the walls
All the shed skins
Finally and to wrap up this post, I want to explain why I named this species as D. cf. puntacta.
According to Hisserdude on https://www.roachforum.com/ - his website and blog Invertebrate Dude
”… I do hear that the main "Diploptera punctata" stock in captivity is probably actually the smaller D.minor, at least I believe that was the opinion of Dominic Evangelista, a taxonomist...”
So according to my seller, these roaches came from an International stock, which would reinforce Hisserdude’s point.
It quite strange for me, since the distribution of Diploptera includes China and Southeast Asia, it doesn’t make much sense to get roaches from abroad when they are locally available… but who knows why has it happened?
Front view of a nymph
Regarding food, I have been feeding them mini turtle food pellets and pieces of beetle jelly. I also notice many of the dried leaves have been nibbled as you can see from the photo down below.
View of the enlcosure
Well, that is all for now! I will keep you posted on this colony development!
Nymph cleaning her antennae
Additional comments by Blattarium on Instagram
“I keep D. punctata too and noticed exactly the same things:
- Mine love feeding on leaf litter even when fresh fruit or beetle jelly is available too.
- They do love climbing upwards. They are always on the top of the enclosure : on the sides and on the bark piece (but never under it).
- And the smell... I read it is supposed to be a defensive odour, but I smell it constantly. They are the stinkiest among my roaches.
- They do love heat. Once our heating system malfunctioned, there was about 30 Celsius in my animal room, and they were still sitting by the heat source where I recorded 34 Celsius...
Thanks for sharing the info regarding their taxonomy, I didn’t about this. I live in Europe, but I have no clue where my culture originates from. I’ll definitely ask around because now I am curious.
Can’t wait for the update on your colony! :)”