Keeping and Breeding Thyropygus sp "Thai Brown and Gold"

Keeping and Breeding Thyropygus sp. “Thai Brown and Gold”

As mentioned in other care guides I have written, this is in no way intended to be the only way to be successful in working with this species. This is just my experience and the methods I used to get this species to breed and successfully rear offspring.
The genus Thyropygus is diverse and spread all throughout Southeast Asia. Roughly 30 species are found in Thailand alone. The species I will be covering in this care guide is the “Thai ​Brown and Gold” looking species (although I know this doesn’t really help at all). A photo will be attached to the end of the guide to show which I am talking about.

The species I am working with was collected by a friend some years ago in the Northern area of Thailand. He found them eating rotten mangoes that had fallen from a tree. These millipedes are predominantly yellow when young with very faint bands. As they mature, the bands darken to a rich brown color around each segment. Males have the typical Spirostreptid bulge at the 7th segment which can be seen while looking dorsally at the animal, making sexing easier than having to uncurl a specimen to check for gonopods. Females on the other hand, lack the bulge at the neck but instead have a more bulbous head that tapers down to the body. Both male and female grow relatively close in size, ranging from ~4” (~10.2cm) to ~6” (~15.2cm) and have 1 small telson spike at the end of the body.

Being from Thailand one would imagine them liking it hot and humid, but that is only partly the case. Adults seem to be fine with temperatures 75-80°F (23.8-26.5°C), but babies do not last long at such temperatures. I couldn’t figure out what exactly was causing such a high mortality rate until thinking about different climates and air flow. If you measure air temperature from the top of a room near the ceiling, you’ll see it’s different below near the floor. That’s because heat rises - just double checking everyone remembers that from elementary school.
The forest floor is no exception.
It wasn’t until separating the colony into 2 tubs in different areas of the room, with different temperatures, did I see a difference. Offspring kept in the original setup and temperature continued dying off at varying rates. Surviving specimens grew slowly. On the other hand, the other tub was thriving. Moving the 2nd setup over to a lower spot near the window was enough to bring the temperature down to between 72-74°F (22-23.5°C) with a night time drop of 68-70°F(20-21°C). This was enough of a temperature difference to allow the offspring to grow and survive to adulthood.
These Thyropygus seem to sexually mature at little over 2 years old, and will continue to grow after until attaining final adult size.
It seems they can tolerate humidity fluctuations well, presumably due to the varying monsoon seasons experienced in their native range. I keep them between 60-70% humidity.

Even though the original specimens were collected eating rotten mango, in captivity I haven’t found them to be all that found of it. Apples and pears seem to be preferred for a supplemental feeding outside of the usual protein sources. They aren’t as voracious rotted wood eaters like Acladocricus are, but they do go through rotted leaves pretty substantially. A thick layer of leaves is essential to keep them from starving.
Although rearing the offspring took me a bit to figure out, getting adults to mate I still haven't determined if it is as simple as having a male and female in the same enclosure. They readily pair up when kept constantly warm without any seasonal cues. But to get offspring to thrive suggests they go through a cooling period. Females do not bury or encapsulate the eggs, rather they lay them scattered under the leaf litter, which is another reason why keeping a thick layer is important.
While the offspring seem to need cooler temperature to survive to adulthood, the females need no environmental stimulation in order to lay eggs.Once laid, eggs take roughly 2-3 months to hatch like lots of other larger millipede species do. Babies emerge white and yellow up within a few molts. It isn’t until they get around 2”(5cm) do the bands start to color up. With each molt the color intensifies until they are a vibrant gold with contrasting deep brown bands.

Hopefully this guide helps clear up some confusion and answer some questions regarding this Thyropygus species, and even more hopeful that it can be used as a stepping stone to figure out how to breed others of the same genus.