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Showing content with the highest reputation on 01/16/2020 in all areas

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    Hi we were just talking about the genus Gromphadorhina and Princisia with Orin on an other topic, and we were talking about their identification wich is difficult, and most of the time incertain. I think that a discussion about this would be really interesting on the forum, so that everyone can access the informations on this subject. Well, the discussion has started like this: me: "But beware, loads of hissers are actually hybrids or misindentified. I bought 3 different species last years, and give a male of each one to a friend of mine. He compared the genitalia with the schema of a scientific book and all the species were misidentified " Orin: "Gromphadorhina descriptions were based primarily on the horn structure of the male, I've seen some of the original descriptions. I'd love to see that schema of hisser genitalia in a scan. Original descriptions based on variable horn structure, pronotum shape and surface texture is why stocks I sent specimens of to a cockroach taxonomist identified as G. portentosa, G. oblongonota, and Princisia all interbreed readily in captivity. They probably are just geographic races and may not even qualify as different subspecies. It is not that people misidentify them, the original "Princisia" never existed and was simply a taxonomic error of someone trying to use a variable specific character as though it were a stable generic character (the notch in the pronotum) without checking to see the male genitalia were identical. However, this does not mean there are not a number of unique stocks that vary in appearance and specific husbandry." So, to continue this conversation, here is the scan: (sorry, he lend the book to someone and we can't remember wich species the genitalias refer to) It's from one of those books: • Herrewege C. van, 1973a – Contribution à l'étude des Blattaria de la faune malgache : I. Princisia, gen. nov., voisin de Gromphadorhina Brunner v. W., description d'une espèce nouvelle – Bulletin de la Société Linnéenne de Lyon. • Herrewege C. van, 1973b - Contribution à l'étude des Blattaria de la faune malgache : II. Description de huit espèces nouvelles appartenant aux genres Gromphadorhina Brunner v. W. et Elliptorhina gen. nov. – Bulletin de la Société Linnéenne de Lyon. According to the books, the pronotum isn't totally reliable: you can find different forms and sizes in a same population. The best way to identify them is the analysis of the genitalia, there are little differences... But they exists. In my opinion, in one hand, we should wait for the revision of those genus, and in a second hand, we should wait for the developement of genetics analysis and compare our hissers to the genetic code of wild hissers. This method is more and more used to identify diptera, we can hope to identify some hissers with this one day, and breed pure Gromphadorhina in captivity! You're probably right Orin, when you say Princisia is just a Gromphadorhina form. And I think that Gromphadorhina portentosa, Gromphadorhina grandidieri, Gromphadorhina oblongonata and Gromphadorhina picea are maybe four subspecies of a same specie, or maybe just geographic forms. There are already some forms known (some colours are related to particular area, other are just selection in bred).
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