218 



Archiblatta, paa is bulge-shaped and its sclerotisation is connected with that of the paa- 

 process (fig.96). Sclerite L4G (fig.92, 325g) resembles L4G of Archiblatta (fig.325f) in 

 its outline and its position in the ventral wall of the vla-lobe and probably represents the 

 L4v-region; however, it cannot be excluded that, additionally, sclerotisations of the L4c- 

 region are contained in this L4G (in its left and anterior parts). 



As compared with Archiblatta, Eurycotis, and Mantoida, some features of Tryonicus can 

 be regarded as derived: The L41-sclerotisation of Tryonicus is (1) broader and (2) divided 

 into two sclerites (L4K, L4N; fig.325d,f,g) by the articulation A5 (fig. 88, 97; compare 

 fig.329a,d,e). (3) The swe-apodeme is completely missing. (4) L4d is directed more 

 anteriad. 



On the other hand, some features of Tryonicus can contribute to the common ground-plan 

 of Blattaria and Mantodea: 



12. As already stated in 6.2.1., feature 4., the connection of the sclerotisations of pda 

 (L41) and paa (L2d) present in Tryonicus and Mantoida is a ground-plan state. The 

 separation of these sclerotisations in Archiblatta and Eurycotis is derived (compare 

 feature 3.). 



13. In Tryonicus and in Mantoida no sclerotisations can be unambiguously assigned to 

 the L4c-region, and a sclerite corresponding to L4F of Archiblatta and Eurycotis is 

 definitely missing. Thus, L4F, and possibly the whole L4c-region, can be regarded 

 as a derived element of Archiblatta and Eurycotis. 



Concerning the common ground-plan of Blattaria and Mantodea, four questions remain 

 open: (1) It cannot be decided if there is a L4c-region. (No sclerotisations undoubtedly 

 homologous with the sclerotisations defined as L4c in Archiblatta, Eurycotis, and Peri- 

 planeta have been identified in any other species). (2) It cannot be determined whether 

 the L41-region is connected with or separated from the L4v-region (or L4c-region, if 

 present) in the anterior ventral wall of the left complex (? in fig.321e), since there is 

 always a connection in Mantodea but never in Blattaria. (3) It cannot be decided if a nla- 

 process is present (but compare in 7.5. (M), (N)). (4) In Tryonicus, Eurycotis, and, if the 

 assumption in 11. is true, in Chaeteessa the regions L41 and L4n are firmly connected. 

 Hence, the separation of L41 and L4n in Archiblatta (sclerites L4C and L4D) might be 

 regarded as apomorphic. However, the position of the connection between L4n and L41 

 is rather different in Tryonicus (to the left of nla, fig.96, 97) and Eurycotis (to the right 

 of nla, fig. 67, 68), and these connections might be non-homologous. Thus, it seems better 

 to regard the respective ground-plan state of L4n (connected with L41 or not) as 

 unresolved. 



6.3.2. The elements in the common ground-plan of Blattaria and Mantodea 



The features 1.-13. in 6.3.1. permit the reconstruction of many ground-plan features of 

 L4, pda, via, and some adjacent elements: (fig.321e,g,i): L4 is composed of sclerotisations 

 in the left edge and in the anterior and right ventral wall of the left complex. The L41- 

 region is located in the left edge and in the anteriormost ventral wall. The swe-apodeme 

 runs along most of L41. swe is massive and beam-like anteriorly and groove-like 

 posteriorly. There is a distinct dorsal extension L4d directed to the right and possibly 



