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Fishery Bulletin 96(4). I 998 
by Hensley (1993) and in part by Nelson ( 1994). Spe- 
cies in Samarinae of Nelson (1984) and Para- 
lichthodes algoensis were classified to Samaridae 
(Nelson, 1994). The subfamilies Pleuronectinae, 
Rhombosoleinae, and Poecilopsettinae, remained in 
Pleuronectidae. Nelson (1994) argued that without 
a comprehensive understanding of monophyly for 
some major groups it is difficult to provide an accu- 
rate revision of the nomenclature within the order. 
Although this approach is an obvious attempt to 
minimize unnecessary changes to the nomenclature, 
it does not reflect the understanding that only spe- 
cies in Pleuronectinae possess a bothoid caudal-fin 
complex that clearly distinguishes these 59 north 
temperate species as being closely related to 
Bothidae, Paralichthyidae, Scophthalmidae, and 
Brachypleura (Hensley and Ahlstrom, 1984; Chap- 
leau, 1993). The Poecilopsettinae, Rhombosoleinae, 
and Samaridae do not have this caudal-fin complex 
and are phylogenetically related to Achiridae, 
Soleidae, and Cynoglossidae (Chapleau, 1993). Given 
that Pleuronectinae is the nominotypical subgroup, 
it is correct to reclassify it to Pleuronectidae. For the 
species of Poecilopsettinae, and Rhombosoleinae, it 
is a misrepresentation of the present cladistic frame- 
work to classify them in Pleuronectidae when the 
order level phylogeny (Chapleau, 1993) suggests a 
relationship with Samaridae, Achiridae, Soleidae, 
and Cynoglossidae. Therefore, only the 59 nominal 
species of Pleuronectinae are considered in this study 
and classified as Pleuronectidae ( sensu Chapleau and 
Keast, 1988). 
Two tribes in Pleuronectinae (sensu Norman, 
1934), the Hippoglossini and Pleuronectini, were clas- 
sified on the basis of jaw morphological characters 
(Nelson, 1984). The Hippoglossini identified by 
“mouth large and symmetrical; maxillae extending 
to or behind pupil of eyes; teeth well developed on 
both sides of jaws, contained ten genera (e.g. 
Atherestes, Eopsetta, Hippoglossoides , Hippoglossus, 
Lyopsetta, Psettichthys, and Reinhardtius).” The 
Pleuronectini were identified by “mouth small and 
asymmetrical; maxillae usually not extending to 
pupil of eye; teeth chiefly on blind-side of jaw and 
contained 16 genera (e.g. Embassichthys, Glypto- 
cephalus, Hypsopsetta, Isopsetta, Lepidopsetta, 
Limanda, Liopsetta, Microstomus, Parophrys, 
Platichthys, Pleuronectes, Pleuronichthys , and 
Pseudopleuronectes)" (Nelson, 1984). Although this 
classification was effective in identifying two mor- 
phological types within Pleuronectinae ( sensu 
Norman, 1934), it was not based on an examination 
of interrelationships within the group, nor did it ac- 
curately identify natural groups. The characters de- 
fining Hippoglossini were all plesiomorphic for the 
order and the characters defining the Pleuronectini 
were also observed in many lineages closely related 
to the Pleuronectinae (sensu Norman, 1934). 
The 59 nominal species in this group had been his- 
torically classified in as many as 28 genera, many of 
which were monotypic. This nomenclature was es- 
tablished prior to any understanding of phylogeny 
and reflected the morphological diversity within 
Pleuronectidae. The number of genera used in iden- 
tifying pleuronectid species would presumably be 
used to accommodate new species as they were dis- 
covered. However, the alpha taxonomy for this group 
has been well established, and only one new species 
of Pleuronectidae, Microstomus shuntovi Borets, 
1983, has been described in the latter half of this 
century. Intuitively, a simplified and more informa- 
tive nomenclature with fewer monotypic genera 
would seem appropriate. 
There are few published studies that have dealt 
with phylogenetic relationships among pleuronectid 
taxa. The most extensive examination of interrela- 
tionships and classification within Pleuronectidae 
(sensu Norman, 1934) was established by Sakamoto 
(1984a). This phenetic hypothesis of interrelation- 
ships among 77 species was not aimed at defining 
relationships within an evolutionary framework; nor 
was it aimed at determining taxonomic structure on 
the basis of natural groups. Sakamoto (1984a) con- 
cluded his study with a reclassification of several 
genera within the Pleuronectinae (sensu Norman, 
1934). In revision, the species of Eopsetta and Lyopsetta, 
as well as Cleisthenes and Hippoglossoides, were re- 
classified into Eopsetta and Hippoglossoides. Glypto- 
cephalus zachirus became Errex zachirus. All species 
of Isopsetta, Parophrys, Lepidopsetta, Limanda, 
Pseudopleuronectes, Pleuronectes, and Liopsetta were 
regrouped under the genus Pleuronectes. Finally 
Paralichthodes algoensis, previously classified in its 
own subfamily, Paralichthodinae (Nelson, 1994), was 
placed within the Pleuronectinae on the basis of over- 
all similarity and the presence of the first neural 
arch, a symplesiomorphy for the order (Hensley and 
Ahlstrom, 1984). 
Chiu ( 1990) examined the relationships among four 
glyptocephaline species (formerly classified in 
Glyptocephalus and Tanakius). The results of this 
phenetic analysis of body shape were similar to 
Sakamoto’s (1984a) results with respect to the rela- 
tionships between Glyptocephalus cynoglossus, G. 
stelleri, and G. zachirus. The limited scope of this 
analysis does not provide adequate information to 
infer relationships beyond these three species. 
Sakamoto’s (1984a) nomenclatural changes and 
classification were adopted in the American Fisher- 
ies Society checklist for flatfish species (Robins et 
