A cladistic analysis of Trombidiidae (Acari: Parasitengona): congruence of larval and adult character sets

Two morphological data sets for eight trombidioid genera (Acari: Parasitengona) were analyzed separately and in combination using cladistic methods. One data set comprised 15 adult morphological characters, whereas the other comprised 29 larval morphological characters. Analyzed separately, the data on adults produced five equally parsimonious trees and the data on larvae produced three equally parsimonious trees. Analyses of both data sets revealed two distinct clades in Trombidiidae: clade A (Podothrombium, Pollicotrombium, Paratrombium, and Trombidium) and clade B (Dinothrombium, Clinotrombium, and Allothrombium). However, the within-clade generic relationships were resolved by data from larvae only in clade A and by data from adults only in clade B. Analysis of the combined data produced a single most parsimonious tree, with both clade A (Podothrombium (Pollicotrombium (Paratrombium, Trombidium))) and clade B (Dinothrombium (Clinotrombium, Allothrombium)) completely resolved. Thus, data on larvae and postlarvae are not only congruent but also complementary in revealing the phylogenetic relationships of these mites. The results support the principle of total evidence and the use of all available data for a single parsimony analysis.