Bayesian tree of GHF5 catalytic domains from members of the nematode order Tylenchida. Genomic and coding sequences (indicated by a yellow box at the base of the relevant branch) from (partial) cellulase catalytic domains were analyzed. Sequences covering the catalytic domain from CD1 to CD6 (as defined in Table 1) are underlined (non underlined sequences are slightly shorter). Identical colors are used for members of the same nematode family. The tree is rooted with genomic cellulase sequences from the fungivorous nematode Aphelenchus avenae (infraorder Tylenchomorpha). Posterior probabilities are given next to each node. Orange circles with or without a bright cross are used to indicate the presence or absence of an intron. An orange cross behind a sequence is used to indicate that the generated piece of a sequence was intronless. Intron numbering is essentially according to Kyndt et al. (2008) . Branch length is calculated in MrBayes, and the scale bar below represents branch length (as number of DNA substitutions/site).