284 



Alternative B: Holophyly of Subgroup 2.2.2. + Subgroup 2.2.3. is supported by three 

 derived character states of the regions L41 and L4d: The anterior and posterior parts of 

 the L41-region (in the primitive case included in the L4K- and L4N-sclerites) are still 

 hinged to each other in Tryonicus (articulation A5) but always far removed from each 

 other in the species of these subgroups (6.3.4.). The utmost right-anterior part of the L41- 

 region, which in Tryonicus extends rightward anterior to the L4n-region, has been lost 

 (6.3.4.). The L4d-ribbon has further rotated (counterclockwise as seen from above) and 

 is now directed to the left. (In Lamproblatta L4d has additionally rotated into a 

 dorsoventral orientation; in subgroup 2.2.3. L4d has been preserved only in Nahublattella; 

 6.3.4). 



Subgroup 2.2.1.: Tiyonicus (parvus and angustus) 



Synapomorphies of the two species of Tryonicus investigated in this paper are the rotation 

 of the pne-pouch (counterclockwise as seen from behind; extreme in T. parvus; 6.1.4.), 

 the enlargement and plate-like condition of the Llm-region, and the consequently hinge- 

 like condition of articulation A2 (6.1.4.). The anterior part of LI has become level (6.1.4.; 

 like in the subgroups 2.1. and 2.2.3.; compare grouping M (24) in 7.6.). 

 Derived features of T. pannis (characters not investigated in T angustus) are the extension 

 R2m of sclerite R2 and the loss of the age-apodeme (6.7.4.; both features also in Lam- 

 problatta: compare grouping G (129) and (130) in 7.6.). The sclerite bridge L3a which 

 connects the L4n-region and L3 and crosses the hla-base 30 is probably also derived 

 (6.4.3.). 



Subgroup 2.2.2.: Cryptocercus + (Lamproblatta + (Ergaula + Polyphaga)) 

 On the left complex, sclerite L4K has been reduced in a specific way (6.3.4.): The parts 

 of L4K which in the ground-plan of subgroup 2.2. (as in Tryonicus) take a position right- 

 ventral to the hla-base have been lost. This concerns mainly the L4n-region, and the 

 anterior insertion of 114 (muscle lost in Polyphaga and Ergaula) is at least mostly on 

 membrane. (In Polyphaga and Ergaula this reduced L4K has shifted to the ventral side 

 of the hla-base). Probably in consequence of this L4n-reduction, the nla-process has been 

 lost (6.3.4.). 



Muscle 12 shows a shift to the anterior: This concerns a gradual anteriad shift of the left 

 insertion (6.3.4.; least distinct in Cryptocercus: insertion still on sclerite L4K, i.e. on region 

 L41) and a complete anteriad shift of the right insertion from the left wall of the pne- 

 pouch to its top (6.1.4.). That the anterior face of the pne-pouch, i.e. of sclerite LI, has 

 become plateau-like (6.1.4.; distinct in Cryptocercus, Polyphaga, and Ergaula; plateau 

 vestigial in Lamproblatta) is possibly correlated with the shift of 12 and is also assumed 

 to be an autapomorphy of this subgroup. That this feature of pne is obsolete in Lampro- 

 blatta is assumed to be a secondarily derived condition, possibly correlated with the 

 apomorphic right- anteriad shift of pne by which the insertion angle of 12 on pne has 

 become very acute. 



Another possible autapomorphy might be the complete loss of muscle s2, which feature, 

 however, is not assessable in Cryptocercus (6.9.). (The loss of s2 in subgroup 2.2.3.2. is 

 certainly a case of parallel evolution since s2 is present in Anaplecta.) 



