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Fishery Bulletin 89(2), 1991 



of S. plagusia and placed in the synonymy of S. tessel- 

 latus (see below). 



Beginning with Kaup (1858), all previously described 

 species of western Atlantic, shallow-water tonguefishes 

 possessing 12 caudal fin rays were regarded as a single 

 species. Kaup placed Achirus ornatus Lacepede, Pla- 

 gusia brasiliensis Agassiz, in Spix and Agassiz (Kaup 

 cited authorship of this species as Cuvier, in Spix), and 

 Plagusia tessellatus Quoy and Gaimard (Kaup listed 

 Valenciennes as the author of this name) in synonymy 

 and proposed the new combination Aphoristia ornata 

 to accommodate a single, widespread species ranging 

 from the Caribbean to southern South America. Gun- 

 ther (1862) regarded Aphoristia ornata as including the 

 nominal species Pleuronectes plagusia Browne, Plagu- 

 sia brasiliensis Agassiz, and Plagusia tessellatus Quoy 

 and Gaimard. 



Subsequent authors, including Jordan and Goss 

 (1889) and Jordan and Evermann (1898), until Ginsburg 

 (1951), continued to include three species in the syn- 

 onymy of Symphurus ( = Aphoristia) plagusia (Schnei- 

 der, in Bloch and Schneider): P. tessellatus, P. brasili- 

 ensis, and A. ornatus. Jordan and his co-workers, and 

 other researchers, still recognized only one widespread, 

 polytypic species of shallow-water, 12-caudal-rayed 

 Symphurus occurring in the western Atlantic. Gins- 

 burg (1951), although continuing to regard all Carib- 

 bean and South American specimens as representing 

 a single widespread, polytypic species, S. plagusia 

 (Schneider, in Bloch and Schneider 1801), allocated his 

 study specimens to two allopatric subspecies. He con- 

 sidered S. plagusia plagusia as a northern subspecies 

 ranging from the West Indies to Central America that 

 was characterized by somewhat lower meristic fea- 

 tures. The second subspecies, S. p. tessellatus, with a 

 more southern distribution along the coasts of Brazil 

 and Uruguay had higher meristic features. In this revi- 

 sion, Ginsburg also described a second species (S. civi- 

 tatum = civitatium, this study) of shallow-water, 12- 

 caudal-rayed tonguefish from continental seas off the 

 southeastern United States and Gulf of Mexico. He 

 equivocated in his description of this new species, 

 stating that his S. civitatium could also be recognized 

 as a third northern subspecies of a widespread, poly- 

 typic S. plagusia. 



Subsequent workers have utilized subspecies desig- 

 nations proposed by Ginsburg for Caribbean and South 

 American shallow-water, 12-caudal-rayed tonguefishes 

 and have used the name S. civitatium for specimens 

 collected in the Gulf of Mexico and along the south- 

 eastern coast of the United States. More recently, 

 however, several studies have noted that both nominal 

 subspecies of S. plagusia occur sympatrically in north- 

 ern South America. For example, Carvalho et al. (1968) 

 found both subspecies in northern Brazil, and Palacio 



(1974) reported both subspecies from the Colombian 

 Caribbean. 



In their revision of western South Atlantic tongue- 

 fishes, Menezes and Benvegnu (1976) reported that all 

 their specimens (collected mostly in offshore habitats 

 by trawling) were quite similar, lacking variation re- 

 ported for specimens collected in more northern 

 regions. Using the name S. plagusia, they considered 

 their specimens to represent a single taxon but also 

 pointed out that the sympatric occurrence of both 

 subspecies in other South American localities indicated 

 that the subspecific status designated by Ginsburg 

 should be reexamined. 



In examining material of S. plagusia, I successfully 

 located 19 of the 25 specimens listed by Ginsburg (1951) 

 in his account of 5. plagusia plagusia. These include 

 representatives of four species: twelve S. tessellatus, 

 one S. caribbeanus, one S. parvus Ginsburg 1951, with 

 only five actually S. plagusia (sensu strictu). The twelve 

 specimens of S. tessellatus incorrectly identified asS. p. 

 plagusia by Ginsburg are small juveniles collected from 

 shallow-water habitats. These, as well as many of the 

 remaining 25 specimens that Ginsburg included in his 

 account of S. p. plagusia, had been collected in the 

 latter part of the last century and during the early 

 1920s. Most of these older specimens were completely 

 devoid of any obvious pigmentation pattern. As a con- 

 sequence, the specimens provided little clue that more 

 than a single species was represented in these shallow- 

 water collections. Additionally, since most of Gins- 

 burg's Caribbean and Central American specimens 

 came from shallow-water collections, very few adult 

 S. tessellatus were available to his study. Therefore, he 

 was unable to unravel size-related differences among 

 the three sympatric species in this complex that occur 

 in this region (the two smaller species, S. plagusia and 

 S. caribbeanus, and the much larger S. tessellatus). 



Ginsburg did not list catalog numbers for 34 speci- 

 mens identified as S. p. tessellatus in his study, so that 

 it is difficult to ascertain if more than one species was 

 included in his account of this subspecies. Of the eight 

 lots designated as 5. p. tessellatus by Ginsburg that I 

 have examined, all are one species, S. tessellatus (Quoy 

 and Gaimard 1824). It is highly probable, therefore, 

 that Ginsburg's S. p. tessellatus are equivalent to 

 S. tessellatus (Quoy and Gaimard 1824) in the present 

 study. 



Comparisons Symphurus plagusia most closely 

 resembles S. civitatium but differs from that species 

 in its modally higher meristic features (total vertebrae 

 modally 49-50 vs. 47-49 in S. civitatium; dorsal fin 

 rays 89-97 vs. 86-93; anal fin rays 73-81 vs. 70-78); 

 and degree of development of sexually dimorphic color- 

 ation. In S. plagusia, both sexes are more or less 



