The absence of morphological synapomorphies supporting our new definition of Notothenioidei has no bearing on the merit of the hypothesis that Percophis and Notothenioidea share common ancestry, a conclusion supported by our molecular phylogeny and not refuted by morphology.
In summary, we are currently unable to find clear morphological synapomorphies which support a placement of Acochlidia within pulmonate taxa, as sister to Eupulmonata.
Possible HGT events Long-branch artifact Barkman et al. [ 9] suggested that the floral similarities between Rafflesia and Passiflora, first noted by Robert Brown [ 23] represent morphological synapomorphies that support the results obtained from the matR gene tree.
A sister group relationship of Evanioidea and Aculeata has been suggested only by the combined morphological and molecular analysis by Sharkey et al. [ 57], and there are currently no convincing morphological synapomorphies that would support this clade.
Moreover, no morphological synapomorphies are known to support a close relationship of Umbraculoidea and Aplysiomorpha/Pteropoda.
The monophyly of the first three of these families has been supported by morphological synapomorphies [ 11].
The monophyly of Heterobranchia is well supported by several morphological synapomorphies like the presence of pigmented mantle organs, longitudinal rows of cilia in the mantle cavity, a chalaze in the egg masses, heterostrophy, and simultaneous hermaphroditism [ 57].
The intra-clitellate position of the Aphanoneura was not supported by reliable morphological synapomorphies [[ 31, 32]; cf. [ 33]], and exclusion of aphanoneurans from the Clitellata was also indicated by most previous molecular analyses [ 8, 14, 31, 34- 37].
In contrast, until now only few morphological synapomorphies, notably placental morphology [ 30], an increase in number of thoracolumbar vertebrae [ 31], and testicondy [ 32], appear to support this grouping.
The mono-phyly of the Tripterygiidae, Blenniidae, Clinidae and Dactyloscopidae are also well-supported by morphological synapomorphies [ 1, 11, 23].
