, the Belostomatidae and Nepidae (Nepoidea) were introduced at the basal position and estimated as a sister group of the remaining nepomorphan families.
In this tree (Figure 4) the first step leads to the upper branch of the infraorder, to the superfamily of the Nepoidea, and the lower branch represents the remaining taxa.
The subsequent branch with a synapomorphy (28-2) leads to several groups except for the Nepoidea and Corixoidea.
They are placed as a basal taxon instead of the Nepoidea (Figure 5).
In 100 parsimonious trees with the same parameters (L, CI, and RI), the nodes change within the range of the analyses, mainly regarding the positions of the Corixoidea and the Nepoidea. Further nodes in terminal taxa are slightly changing and most of those nodes have very low Bremer values, suggesting little or no confidence in the groupings.
His scheme is similar to that of Rieger (1976) in the placement of Nepoidea [i.e., (Nepidae + Belostomatidae), see Schuh and Slater 1995:110] as sister group to the remaining Nepomorpha, and in having as the most derived clade the Notonectoidea [i.e., (Notonectidae + (Helotrephidae + Pleidae))].
Their analysis place Nepoidea as the most basal group, and Corixidae as sister group remaining Nepomorpha, similar to the proposal of Mahner (1993).