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r2, r3, s2, s4), and some morphological details (keel 3, edge 16). The right phallomeres 

 of all other Blattaria studied can be derived from that of Eurycotis without any problems; 

 especially the area comprising sclerites R2 and R3, invagination cbe, and muscle r2 is 

 very similar in all species. Therefore, homology is assumed for all these right phallomeres. 

 This assumption also includes those species with the right phallomere situated on the left 

 side (Nahublattella, Supella, Euphyllodromia, Byrsotria, and Blaberus investigated in this 

 paper): The right phallomeres of these species can be integrated into the homology 

 hypothesis without any problems, and the right phallomeres of Blaberus and Byrsotria 

 (situated on the left side) and the right phallomere of Nyctibora (situated on the right side) 

 are nearly identical. (The only principal difference is the fusion of RIP and RIS to form 

 RIT in the two blaberid species). 



The left complexes of Mantoida and of Archiblatta and Eurycotis are quite similar in the 

 principal arrangement of the sclerotisations (LI, L2, L4), the formative elements (e.g. 

 pouches Ive and pne, ventral lobe via, apodeme swe, processes paa and pda), the main 

 muscles (12, 13, 14, 16, 19, si, s3), the genital opening, and some morphological details 

 (L4d-region). Most of the morphological gaps between these species are bridged by other 

 Blattaria, e.g. Tryonicus (shape of paa and pda and relation between them), Polyphaga 

 (shape of sclerites LI and L2, position of phallomere-gland opening), or Cryptocercus 

 (muscle 11). The left complexes of the other Blattaria (e.g. Parcoblatta) can be extremely 

 different from those of Archiblatta and Eurycotis, but the morphology of each species can, 

 if several other species are included in the comparison, be traced back to the basic pattern. 

 Therefore, homology is assumed for all these left complexes. This assumption likewise 

 includes those species with the left complex situated on the right side {Nahublattella, 

 Supella, Euphyllodromia, Blaptica, Nauphoeta, and Blaberus investigated in this paper): 

 The left complexes of these species can be integrated into the homology hypothesis without 

 any problems. The left complex of Blaberus (situated on the right side) and the left 

 complex of Parcoblatta (situated on the left side) are very similar; concerned are the 

 principal arrangement and shape of most cuticular elements, the course of most muscles, 

 as well as many details (ate-tendon, hge-groove, notch 45). Differences between Blaberus 

 and Parcoblatta are in most cases bridged by other species of Blattellidae and Blaberidae: 

 Loboptera and Nyctibora (orientation as in Parcoblatta) have, like Blaberus, a sclerite 

 L4U, which is missing in Parcoblatta. Nauphoeta (orientation as in Blaberus) has, like 

 Parcoblatta, a muscle s7, which is missing in Blaberus. The Ive-apodeme and the via- 

 process of Nyctibora (orientation as in Parcoblatta) and Nauphoeta (orientation as in 

 Blaberus) are very similar and do not show the strong differences as present between 

 Parcoblatta and Blaberus (which are due to the differently directed rotation of this area). 

 From the homology of the right phallomeres and from that of the left complexes it follows 

 that the asymmetry of the whole phallomere complex is homologous in all species studied. 

 Thus, the asymmetry of the phallomere complex is a feature of the common ground-plan 

 of Blattaria and Mantodea (and maybe Isoptera). Moreover, from a comparison of the 

 ground-plan morphologies of the left complex (fig.321e,g) and of the right phallomere 

 (fig.321f,h) it follows that the asymmetry of the phallomere complex was in the common 

 ground-plan of Blattaria and Mantodea already as extreme and of the same very special 

 kind as in the extant species. For the investigated members of Plectopterinae 



