256 



Parcoblatta, Blaberus, and other Blattellidae and Blaberidae 



The morphology of the posterodorsal part of the right phallomere of Parcoblatta and 

 Blabenis is in some repeats very different from Anaplecta and Nahublattella. Concerned 

 are two areas, which will be discussed separately: (1) the Rlt-region and (2) the dorsal 

 lobe fda. The essence of the changes having taken place can be understood by considering 

 the morphology of some more blattelhd and blaberid species included in this investigation. 



The Rlt-region Within Blattellidae and Blaberidae the Rlt-region (with pva) 

 undergoes some changes which also involve R2. These developments are shown in 

 fig.330n-s. 



Anaplecta has Rlt (fig.330n, 34 in fig.226) in the same relative position as e.g. Tryonicus 

 (fig 330h): situated in the dorsal wall of cbe, connected with Rlc to the right, articulated 

 with R2 to the left (A6). In contrast to Tryonicus, the left end of Rlt shows the hook- 

 like curvature, which is a derived feature. 



Euphyllodromia has a similar ribbon-like sclerotisation in the dorsal wall of cbe (fig.330o), 

 which by its position can be identified as the Rlt'-region. The right end of this Rlt' 

 approaches, Hke in Anaplecta, the Rlc'-sclerotisation immediately behind articulation A3 

 but is narrowly separated from Rlc' by membrane (at cl in fig.330o). The left end of Rlt' 

 shows, like in Anaplecta, a hook-like curvature, but this curved part is swollen to the 

 interior of the phallomere by extensive thickening of the cuticle (ewe in fig.330o). 

 Moreover, the left end of Rlt' is not articulated with R2' but fused to it (at 6* in fig.330o). 

 Thus, the former sclerite RIN' has divided (at cl) into two new sclerites: RIS' (Rlt'- 

 region, now firmly connected with R2') and RIP' (rest of the former RIN'). The 

 separation of Rlt' from Rlc', its fusion to R2', and the cwe-thickening are derived 

 features. 



Nyctibora shows the same situation (fig.330r), but Rlt (sclerite RIS) and the rest of Rl 

 (sclerite RIP) are slightly farther removed from each other, (i.e. the two points of division, 

 called cl again, are farther away from each other). The cwe-thickening and its curvature 

 are very distinct (fig.319). 



In Parcoblatta, Blaberus, and Byrsotria the fusion of Rlt and R2 and the cwe-thickening 

 are very similar to Nyctibora (fig.282, 283, 285 and 309, 310, 313), and ewe marks the 

 border between R2 and Rlt (with ewe belonging to Rlt). However, the condition of the 

 right end of Rlt varies: In Parcoblatta (fig.330q, 281, 282) this end of the Rlt-region 

 (sclerite RIS) is still free. It has been far removed from its previous point of contact with 

 Rlc (sclerite RIP) (or, in other words, Rlt has been shortened; compare the el-points in 

 fig.330q and r). Instead, it has approached the opposite end of sclerite RIP. 

 In Blaberus (fig. 330s, 309) and Byrsotria (fig.318) the Rlt'-region is firmly connected 

 with the rest of Rl'. From the phylogenetic context, discussed later in 7.3., it follows that 

 this is due to a secondary fusion of the sclerites RIS and RIP and does not correspond 

 to the primary connection of these sclerotisations within the RlN-sclerite of Anaplecta, 

 Nahublattella, and Supella (fig.226, 253, 330n,o,p). Therefore, the resulting sclerite, 

 though having the same composition as RIN, is named differently: RIT'. (The 

 sclerotisations contained within RIN and RIT' are homologous throughout but the 



