327 



the same course (Mizukubo & Hirashima, fig. 6, 8). The intensities of the mutual 

 relations between the subregions are almost never the same in the two species. 



The special moiphology of the supposedly homologous subregions (e.g. position in a 



pouch, formation of a process) is not considered at all. 



The symmetry of the phallomere complex in the Blattarian ground-plan 



The investigations and conclusions of Mizukubo & Hirashima are restricted to Blattaria; 

 Mantodea are not mentioned at all. With their statement "We cannot detect proto-types of 

 the genitalia .... indirectly on evidence obtained from other insect groups." (p.250) the 

 authors deprive the phallomeres of Mantodea of any value to contribute to the 

 reconstruction of the ground-plan of the Blattarian phallomeres. However, in the 

 reconstruction of the ground-plan of any group an outgroup comparison can be very useful. 

 In the case of the Blattarian phallomeres the consideration of the Mantodean phallomeres 

 was of great value for the determination of the polarities of characters within Blattaria 

 (and within Mantodea). Since Mizukubo & Hirashima neglect Mantodea, the statement 

 "We believe that, at the period of the formation of the order, the early Blattaria had 

 symmetrical genitalia" has no foundation at all. According to this statement, the asymmetry 

 of the Blattarian and the Mantodean phallomeres is a case of parallel evolution. However, 

 my results clearly suggest that the very special kind of asymmetry present in Blattaria and 

 Mantodea is homologous and a feature of their common ground-plan. 

 Mizukubo & Hirashima recognise the side-reversed similarities in the phallomeres of 

 Blattellidae {Blattella) and Blaberidae (Opisthoplatia). However, they do not assume 

 homology for these similarities but parallel evolution due to similar selective pressure. 

 Hence, they assume completely symmetrical phallomeres even for the last common 

 ancestor of Blattellidae and Blaberidae. These opinions are refuted: 



- Since extreme asymmetry had already been established in the common ground-plan of 

 Blattaria and Mantodea, it must have been present in the common ancestors of 

 BlatteUidae and Blaberidae, too. 



- The similarities of the left complexes of Blaberidae and the more derived Blattellidae 

 (Nyctibora, Parcoblatta) are so detailed and peculiar that the probability for parallel 

 evolution is in my view infinitely small; side-reversal is substantially ascertained by my 

 results (compare in 6.13.). 



- That a reversal of the left-right asymmetry must be considered as a possible evolutionary 

 pathway is clearly demonstrated by those species of Ectobius (Ectobiinae) having side- 

 reversed phallomeres (compare in 6.13.). 



9. HOMOLOGY RELATIONS ACCORDING TO GRANDCOLAS (1994) AND THE 

 PHYLOGENETIC POSITION OF CRYPTOCERCUS 



Apart from other morphological studies, Grandcolas & Deleporte (1992) and Grandcolas 

 (1994) investigate the phallomere sclerites of some Blattaria. The latter paper contains 

 nearly all the information given in the former, and also some additional data, and will be 

 referred to in the following discussions. 



