Sand Roaches or Polyphagids
Corydiidae, previously known as Polyphagidae, is a family of the order Blattodea. Many are known as sand cockroaches. The family is divided into five subfamilies, comprising some 40 genera. And I got two new species into my collection!
Corydia is combination of two words, Cory comes from Greek κορυς, which translate to maiden or female, but seems to be related to heart feelings and Dia which translates to something divine. Which would match the description of a Eucorydia (Eu before the Corydia means “good”) yasumastui adult shining gloriously in bright light.
On the other hand, polyphagid is basically a multi eater, in this case a roach which can eat several foods, being very adaptive.
The reason why I like to explore the latin/greek roots of the words, is because I feel it takes me closer to the mind of the person who named them, and what characteristics he found more appealing or distinctive at that moment.
So I got a colony of Polyphaga plancyi (the Chinese Sand Roach), consisting of 2 mature males, 8 mature females and around 15 mixed (small size) nymphs and 2 oothecas and a colony of 20 small nymphs of Eupolyphaga sinensis (the Chinese Medicinal Roach).
I don’t have any experience with Eupolyphaga or Polyphaga genus, so of course I had to go to the bibles:
1 - The InvertebrateDude Polyphaga aegyptiaca & saussurei caresheet - “This caresheet should also be applicable to Polyphaga obscura, and probably the other Polyphaga species as well, (though development times may vary between species).”
2 - Orin McMonigle’s Book “For the Love of Cockroaches”.
3 - Roachforum.com
Polyphaga plancyi setup - a well ventilated critter box with lid, filled with a mix of cocofiber, decaying wood and decaying leaves.
Polyphaga plancyi setup - top view
Humidity is on the lower end but the total height of substrate is considerable, to allow me to have a gradient if necessary.
Polyphaga plancyi setup - side view
I will post more macro photos soon. For now, these will have to do :D
Polyphaga plancyi - all development stages
The early stage nymphs are small and seem rather soft, but after two or three molts, they start to get their darker colorations and a wider body.
Polyphaga plancyi nymph
The adults females are large, round, thick and hard shell. They cannot climb glass, but will be able to climb plastic up to a certain point, even if clumsy. The female is characterized by the distinct yellowish markings which other Polyphaga species do not exhibit.
Polyphaga plancyi adult female - note the beautiful red markings
Polyphaga plancyi adult female - extremely thick roach
The males are dark and smaller than the females, aprox half their size. The males I got seem to have passed a rough time, as they are both lacking most of their wings ends. They also cannot climb glass, but will be able to climb plastic if they get a grip.
Polyphaga plancyi adult male
As for the Eupolyphaga sinensis, since I only got small nymphs, I am housing them on the following enclosure.
Eupolyphaga sinensis setup - side view
This is medium/well ventilated box with lid, filled with a mix of cocofiber, decaying wood and decaying leaves. It has the same level of humidity as the P.plancyi but the box has a smaller amount of ventilation as well as a smaller height of substrate. It won’t be possible to have a big humidity gradient, but it will be possible to retain an uniform humidity level for longer.
Eupolyphaga sinensis nymph
One of the most interesting aspect of Eupolyphaga sinensis is that is very used in China for Entomotherapy, the medicinal use of insects as medicine, hence the common name Chinese Medicinal Roach. Insects and the substances extracted from them have been used as medicinal resources by human cultures all over the world. Besides medicine, these organisms have also played mystical and magical roles in the treatment of several illnesses in a range of cultures. Science has already proven the existence of immunological, analgesic, antibacterial, diuretic, anesthetic, and antirheumatic properties in the bodies of insects.
In China, roaches are sold in drugstores because they are thought to stimulate lactation, and in Harbin the species Eupolyphaga sinensis Walker and Polyphaga plancyi Bol. are said to regulate menstruation (Lenko and Papavero 1996).
This is my first try with these species, and it seems they like to eat more dry foods compared to fruits and veggies. But lets see how my experience keeping them goes.
Wish me luck!
To wrap up the post, and once again, I will post better photos at a later stage, and update this post with a notice.
Thank you for your time to read the post and passing by. Let me know if you have any comments, and I will post updates in few months, as I know these species will take some time to develop.
Cheers!