Great, sounds like you have a head start, and a interesting purpose as well.
In some species of mantids, for example the
Orchids (Hymenopus coronatus) it is said between 3 to 5 inbreed generations and defected and/or sterile nymphs are the result (as discussed from some various breeders of the species). The problem encountered thought by several breeders, is from the various Orchid mantids in the hobby all originating from the same original mantid parents. So mixing in some further distant related Orchids are needed to keep their gene pool from mutating.
In reality though there are many who still seem to be oblivious (or just ignore) the US Customs/import laws and get new specimens anyway. It is difficult to know if any of their offspring however make it into the general hobby breeding stock. As such no one can seem to confirm or deny what the real cause of the Orchid mantis inbreeding issue truly is.
Thankfully, in nearly all other mantid species it doesn't seem to be a issue at all, as mentioned by other breeders. Personally I've only typically done one generation of inbreeding various species without problems. Typically as I keep native species, and as such I always have new parents/stock from wild captive specimens in the gene pool - or I am ready to try a new species by that point.
Indeed the Rhombodera sp. are great for beginners (and some seasoned keepers still prefer them) and is one of the largest in size, and beats species in the same length category even (like the Tenodera sinensis) by the overall size and girth - making them appear much larger.
If you are just looking for a beginner list or such, here is my default response I keep on hand for new members.
Where to buy
To start with you can buy mantids from the
classified section (see the
feedback section about the sellers too). Of course there are many great sites to buy mantids and related goods from online such as
BugsInCyberspace,
MantisPlace, and
MantisPets the most common and recommended for mantis themselves.
Beginner mantis species
Ghosts (Phyllocrania paradoxa) are great and tame easily, and have a very exotic look but are a very hardy species - recommended for beginners too. Chinese mantids (Tenodera sinensis) are a great option as they are a naturalized species so can be captured in the wild - I can collect over a hundred locally in a few weeks here. The Chinese mantids also grow large at about 4", which means they also are hungry pigs.
One of my favorites has to be Carolina mantids (Stagmomantis carolina) as they are a native species, and extra nymphs from a ooth can be released (again this is another species that can be found wild locally). They seem to have individual attitudes/traits, take to handling and various feeders well, etc. Likely though I have a soft spot for them as I got started in the hobby rescuing my first mantid from a winter freeze while at work. They do require a bit more care, but if you can mange humidity and feeding properly, I doubt you'll have problems with the species as it was my first.
Some great beginner mantid species though are Flower mantis (Creobroter sp.), Giant shield/hooded mantis (Rhombodera sp.), African mantis (Sphodromantis lineola), Budwing mantis (Parasphendale affinis or Parasphendale argrionina), Chinese mantis (Tenodera sinensis), Double shield mantids (Pnigomantis medioconstricta), Ghost mantis (Phyllocrania paradoxa), Giant Asian mantis (Hierodula membranacea), and Griffin mantis (Polyspilota griffinii). Although some are not necessary listed as typical beginner species, they are all hardy, and seem to do fine even with beginners.
Have fun searching and getting started.
