Cooper and Chapleau: Monophyly and intrarelationships of the family Pleuronectidae 
713 
simonious trees. A postocular ridge is observed in only 
one other pleuronectid taxon, Dexistes rikuzenius. A 
single row of teeth in the upper jaw was also observed 
in Psettichthys melanostictus, Glyptocephalus, and 
Microstomus . The structure of the dorsal crest, ex- 
tending along the supraoccipital and blind-side fron- 
tal, was homoplastic within Pleuronectini and in 
other pleuronectid lineages. Limanda aspera, 
Pleuronectes quadrituberculatus, P. glacialis, P. 
pinnifasciatus, and P. putnami retain a prominent 
crest. Pleuronichthys verticalis, Cleisthenes, and 
Reinhardtius stomias share the reduced morphologi- 
cal character with Pleuronectini. 
Intrarelationships of Pleuronectini 
Genus Parophrys The first lineage in Pleuro- 
nectini has only one species, Parophrys vetula, which 
is distinct with five character transformations (Fig. 
17): suture between first and second basibranchial 
(4, Fig. 3A); haemal spines broadly attached to ven- 
tral surface of centrum (73), are both reversals within 
Pleuronectidae; absence of dentary foramen on ocu- 
lar side (99); reduction of teeth on ocular-side dentary 
(67) and incisorlike teeth (70, Fig. 9D) are shared 
with higher lineages within Pleuronectini but are 
homoplastic, and observed in Microstomini and spe- 
cies of Hippoglossinae. 
Limanda, Platichthys, Pleuronectes, and Pseudo- 
pleuronectes represent the second lineage in Pleuron- 
ectini and are hypothesized to share an immediate 
common ancestor on the basis of three synapo- 
morphies (Fig. 17): presence of a blind-side postocu- 
lar ridge (100); presence of bony prominences on ocu- 
lar-side postocular ridge (101, Fig. 10E); and pres- 
ence of an interpterosphenoid bar (98, Fig. 16). The 
blind-side postocular ridge and bony prominences on 
the ocular-side postocular ridge are unique within 
Pleuronectidae. The latter was not observed in 
Limanda limanda, L. sakhalinensis, L. aspera, 
Pseudopleuronectes herzensteini, P. yokohamae, and 
P. americanus. The presence of an interpterosphenoid 
bar was not observed in Limanda limanda, L. 
sakhalinensis, Pseudopleuronectes schrenki, and P. 
herzensteini and is homoplastic in Glyptocephalus 
cynoglossus, G. stelleri, G. zachirus, Psettichthys, 
Acanthopsetta, and Hippoglossoides . 
