exception of the apparent higher number of 

 gill rakers (tables 8 and 9) in the Pacific popu- 

 lation. This exception results from the indis- 

 tinction of the anterior one or two rakers in the 

 larger specimens because of encroachment by 

 the surrounding spinous areas. The Pacific 

 specimens were smaller than those from the 

 Atlantic by an average of 69 mm. ; this is 

 about one-fifth of the largest Atlantic (341 

 mm.) and the largest Pacific (346 mm.) speci- 

 mens available. In spite of the apparent dif- 

 ference in the number of gill rakers between 

 the Atlantic and Pacific populations, the over- 

 lap is broad and the mean difference small. The 

 Atlantic and Pacific populations do not differ 

 in other characters studied, as discussed below. 

 The number of anal rays (9) not shown in the 

 tables is constant in the Atlantic and Pacific 

 populations. 



The Atlantic and Pacific populations of A. 

 nemoptera appear to differ slightly in the 

 height of the dorsal and anal fins, the length 

 of the last dorsal ray, the length of the caudal 

 lobes, and the number of gill rakers. These 

 differences, however, do not justify separation 

 at the species level and, probably, not even at 

 the subspecies level. The alleged differences 

 described by Beebe (1942) all break down 

 when adequate material is analyzed. 



The following is an itemized description of 

 qualitative characters. 



Heart. — The heart of one adult Atlantic 

 specimen was dissected. It has two rows of 

 valves in the conus as in A. vidpes. 



Gular plate.— RMebvawA (1963: 132), the 

 last reviewer, and most preceding authors, 

 stated that a gular plate is absent in the family 

 Albulidae; however, Nybelin (1960: 78) has 

 demonstrated its presence in A. vulpes. Fol- 

 lowing Nybelin's method (alizarine stain), we 

 found that A. nemoptera has a gular plate, 

 similar to that of A. vidpes. 



Dentition. — A detailed description of Pacific 

 specimens' dentition was given by Beebe 

 (1942). Atlantic specimens are in full agree- 

 ment with that description. As indicated by 

 Beebe, there is considerable ontogenetic varia- 

 tion in the teeth. 



Coloration. — The life colors, based on Pa- 

 cific specimens, were described by Beebe 



(1942). Two specimens (UMIM 1028) col- 

 lected in Port Antonio, Jamaica, were in agree- 

 ment with Beebe's description. Preserved ma- 

 terial has longitudinal dark lines, between the 

 rows of scales, especially above the lateral line. 

 There are an elongate black dash anteriorly on 

 each side of the snout and a median anchor- 

 shaped mark on the tip of the snout extending 

 ventrally towards the mouth. 



Size. — The largest known specimen from the 

 Atlantic (Colombia, UMIM 5927) is 341 mm. 

 in standard length, and the largest known 

 Pacific specimen (Acapulco, Mexico, USNM 

 75547) is 346 mm. 



Se.x ratio. — The 19 Colombian specimens 

 were sexed : 9 mature males and 10 mature 

 females. 



Range. — In the Atlantic the species is now 

 known to occur along the Caribbean coasts of 

 Venezuela, Colombia, and Panama, and at 

 Jamaica and Hispaniola. In the Pacific it is 

 known from Mazatlan and Acapulco, Mexico, 

 and from Costa Rica and Panama. 



RELATIONSHIPS WITH ALBULA VULPES 



A. nemoptera and A. vulpes differ in several 

 proportional characters, especially those per- 

 taining to mouth structures and to the elonga- 

 tion of the last dorsal and anal rays into a 

 filament in A. nemoptera (table 1). These 

 characters, as well as meristic differences 

 (tables 3 to 11) leave no doubt as to the specific 

 distinction between A. nemoptera and A. 

 vidpes. As already discussed, however, these 

 are differences of degree not to be considered 

 of generic importance. More basic structural 

 characters such as the presence of a gular plate 

 and two rows of valves in the conus arteriosus 

 are common to both species. 



Differences in dentition between A. nemop- 

 tera and A. vulpes are, again, of degree. The 

 premaxillary, dentary and palatine teeth are 

 larger in A. nemoptera. Also in A. nemoptera 

 the premaxillary band of teeth is two or three 

 teeth wide at the symphysis and three or four 

 in A. vulpes. The parasphenoid and entoptery- 

 goid teeth, however, are larger and fewer in A. 

 vulpes. Maxillary teeth are present in juvenile 

 and young adult A. nemoptera to about 250 

 mm. in standard length, whereas maxillary 



BONEFISH SYSTEMATICS AND BIOLOGY 



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