Quote Originally Posted by JeffreH View Post
Virtually identical. There is some nutritional data floating around that suggests that most feeder cockroach species vary insignificantly in basic nutritional composition. They will have varying micronutrient composition, so offering a variety of roaches or other feeders will still be highly beneficial for your pet. Later instars and adults (particularly males) are much more scleritized (harder exoskeleton); which tends to go hand-in-hand with chitin mass, so don't feed anything that is too large for your frog to handle as adult hissers are quite large and also have some spines/spurs on their legs . The nymphs make fantastic feeders... just remember they can swiftly climb smooth surfaces like glass and can squeeze out of very small openings.

Nutitional Comparison of Roach species with common feeders:
Feeder Insect Analysis

My experience with Malagasy Hissers (G. portentosa) is that they mature at close to the same rate as Blaptica dubia - probably averaging close to 5-6 months to reach maturity after about 6 instars. Their gestation period is nearly twice as long as B. dubia (close to 2 months), but they also incubate oothecae internally and give live birth that can greatly exceed a typical B. dubia litter... probably average around 45 babies and as much as 60+ from a single mature female. This is somewhat speculation; I keep several hisser species for hobby and don't tend to keep serious records on them.
good info jeff. you posted while i was writing mine lol. On a side note i have also gotten pretty close to 60 young out of one dubia female. I have seen on more then one occassion this size of birth. As many as i am producing every two months it is only logical that each female is berthing a lot more then 35 babies each. And I have yet to find a care sheet online that says 35 to 60 babies each birth. I dont know where these roach sellers are getting there info but to me they seem to have more facts wrong about them then right. I say all this because i also believe these two species are very similar like you said. They even have very closly to the same nutional value regardless of the size difference.