298 



7.5. Remarks on the polarity and evolution of some characters 



For some characters the polarity assumptions in 7.1.-7.4. are not yet sufficiently 

 substantiated. In some cases the polarity question can be settled by a detailed discussion 

 of morphology, homology, or functional intercorrelations. The respective discussions will 

 be largely independent of the phylogenetic hypothesis in 7.4. In other cases a solution of 

 the polarity question can only be approached by a reciprocal consideration of the various 

 arguments or possibilities in terms of parsimony, i.e. a weighing of the various possible 

 polarity assumptions against the assumed autapomorphies of the subgroups defined in 7.2. 

 and 7.3. and against the outgroup comparison between Blattaria and Mantodea. The 

 respective discussions will be done in interdependence with the phylogenetic hypothesis 

 in 7.4. 



The following discussions under (A)-(C) are concerned with the polarity of three 

 characters for which the outgroup comparison between Blattaria and Mantodea is 

 somewhat conflicting since the same two character states are present in Blattaria as well 

 as in Mantodea. The question arises whether that character state represents the ground- 

 plan condition which in 7.1. has been assumed to do this. (A similar conflict is also present 

 in (G), which will be discussed below.) These discussions will be independent of the 

 phylogenetic hypothesis in 7.4. 



(A) The connection or separation of the sclerotisations L2d and L41 of the processes paa 

 and pda and the length of paa and pda 



The area bearing the paa- and pda-processes is very similar in Mantoida (fig.44) and 

 Tryonicus (fig.91): The sclerotisations of paa (L2d-region) and pda (L41-region) are 

 connected; paa and pda are completely sclerotised, are bulge-hke and short, paa being 

 somewhat upcurved, and are close to each other. This has been regarded as the condition 

 of the common ground-plan of Blattaria and Mantodea (6.2. 1., 7. 1.). 

 In other Blattaria (6.2.1., 6.2.4.) as well as in other Mantodea (6.2.3.) paa and pda can 

 be longer, and their sclerotisations can be separated from each other. Alternatively, these 

 two states could be regarded as the ground-plan states of the respective characters, but 

 there are some arguments against this view: Within Blattaria the sclerotisations are 

 separated in Eurycotis (fig.66), Archiblatta (fig. 53), and Cryptocercus (fig. 150). This 

 separation is accompanied ( 1 ) by a reduction of the sclerotisation of one of the processes 

 in Cryptocercus (pda) and in Archiblatta (paa), and (2) by a far separation of the processes 

 themselves in Eurycotis and Archiblatta, which feature is correlated with the recess of the 

 posterior part of the Ive-pouch to the right (6.2.1.). These accompanying conditions in 

 Eurycotis, Archiblatta, and Cryptocercus are clearly derived features, and the separation 

 of the paa- and pda-sclerotisations can easily be explained as correlated with these and 

 as being derived, too. In Chaeteessa (fig.34), Metallyticus (fig.25), and Sphodromantis 

 (fig. 11) the sclerotisations of paa and pda are separated from each other without being 

 reduced (with the exception that in Chaeteessa the whole pda has been lost), and the close 

 vicinity of paa and pda has been retained. According to these very different concomitant 

 circumstances in Cryptocercus, in Archiblatta + Eurycotis, and in the respective Mantodea, 



