Data from: The evolution of pharyngognathy: a phylogenetic and functional appraisal of the pharyngeal jaw key innovation in labroid fishes and beyond

The perciform group Labroidei includes approximately 2,500 species and
comprises some of the most diverse and successful lineages of teleost
fishes. Composed of four major clades, Cichlidae, Labridae (wrasses,
parrotfishes and weed whitings), Pomacentridae (damselfishes), and
Embiotocidae (surfperches), labroids have been an icon for studies of
biodiversity, adaptive radiation, and sexual selection. The success and
diversification of labroids have been largely attributed to the presence
of a major innovation in the pharyngeal jaw apparatus, pharyngognathy,
which is hypothesized to increase feeding capacity and versatility. We
present results of large-scale phylogenetic analyses and a survey of
pharyngeal jaw functional morphology, that allow us to examine the
evolution of pharyngognathy in a historical context. Phylogenetic analyses
were based on a sample of 188 acanthomorph species, primarily percomorphs,
and DNA sequence data collected from ten nuclear loci that have been
previously used to resolve higher-level ray-finned fish relationships.
Phylogenies inferred from this dataset using maximum likelihood and
Bayesian analyses indicate polyphyly of the traditional Labroidei and
clearly separate Labridae from the remainder of the traditional labroid
lineages (Cichlidae, Embiotocidae, and Pomacentridae). These three
“chromide” families all grouped together within a newly discovered clade
of 40 families and more than 5,300+ species (>30% of percomorphs
and >17% of all ray-finned fishes), which we name Ovalentaria for
its characteristic demersal, adhesive eggs with chorionic filaments. This
fantastically diverse clade includes some of the most species-rich
lineages of marine and freshwater fishes, including all representatives of
the Cichlidae, Embiotocidae, Pomacentridae, Ambassidae, Gobiesocidae,
Grammatidae, Mugilidae, Opistognathidae, Pholidichthyidae, Plesiopidae
(including Notograptus), Polycentridae, Pseudochromidae, Atherinomorpha,
and Blennioidei. Beyond the discovery of Ovalentaria, this study provides
a surprising, but well-supported, hypothesis for a convict-blenny
(Pholidichthys) sister group to the charismatic cichlids and new insights
into the evolution of pharyngognathy. Bayesian stochastic mapping
ancestral state reconstructions indicate pharyngognathy has evolved at
least six times in percomorphs, including four separate origins in members
of the former Labroidei, one origin in the Centrogenyidae, and one origin
within Beloniformes. Our analyses indicate that all pharyngognathous
fishes have a mechanically efficient biting mechanism enabled by the
muscular sling and a single lower jaw element. However, a major
distinction exists between Labridae, which lacks the widespread,
generalized percomorph pharyngeal biting mechanism, and all other
pharyngognathous clades, which possess this generalized biting mechanism
in addition to pharyngognathy. This suggests that labrids have a
functionally more restricted pharyngeal system than all other
pharyngognathous clades.