The tentorium and anterior head sulci in Dictyoptera and Mantophasmatodea (Insecta)

The tentorium, the anterior sulci of the head capsule (epistomal, subgenal, subantennal, circumantennal, and circumocular sulci), and the extension of the anterior tentorial pit were studied in 26 species of Blattaria (representing most principal lineages), 4 species of Mantodea (including the basal Mantoida schraderi.), and I species each of Isoptera (the basal Mitstotermes darwiniensis) and Mantophasmatodea (Austrophasina caledonense). The morphology of these head structures is compared with literature data on other insect orders, mainly Phasmatodea, Orthoptera, Dermaptera, Embioptera, and Plecoptera, and partly Odonata and Zygentoma. Characters are defined, presented in a matrix, and evaluated with regard to phylogenctic implications and homoplastic evolution. The structural relationships of the subantermal sulcus to the subgenal, circumocular, and circumantermal sulci, which are highly variable and strongly homoplastic (depending much on the size of the compound eyes) are a focal issue; several types of subantermal sulci are defined. The presence of an anterior transverse bridge in the tentorium (perforated tentorium) of all Dictyoptera here studied confirms the monophyly of this group. Mantophasmatodea lacks this element. (c) 2007 Elsevier GmbH. All rights reserved.