COLLETTE ET AL.: SCOMBROIDEI 603 



Table 156. Characters for Gempyud Larvae, Juveniles and Adults and Our Knowledge of Gempylid Larvae and their Occurrence. 



• Nealotus has .^ fin spine-ray elements associated in larvae and juveniles. The middle element gradually fuses to the long posterior process of the first anal pterygiophore. 



juveniles of Nealotus. The great variability in vertebral counts 

 suggests that more than one species exists in the genus Nealotus. 



Thyrsiloides marleyi. — Thyrsiloides larvae are unknown. This 

 is not surprising since the adults are considered to be rare (Nak- 

 amura. 1980). 



Nesiarchus nasutus (Fig. 318).— The larvae of Nesiarchus are 

 well known. Giinther (1887) described a 33 mm pre -juvenile 

 specimen. A size series of 26 specimens 5.1-23.5 mm NL or 

 SL from the Atlantic Ocean was described by Voss (1954). The 

 5.1 mm NL specimen shown in Voss (1954: fig. 3A) and iden- 

 tified as Nesiarchus is Gempylus serpens because of the mid- 

 lateral pigment stripe and the large number of myomeres as 

 indicated by the close spacing. Nesiarchus larvae are easily iden- 

 tified by a heavily pigmented gular membrane. Larvae larger 

 than 6 mm develop pigment in the hypural area and a distinct 

 pigment stripe from the tip of the snout to the eye. One of us 



(PotthofT) obtained many vertebral counts from post-larval 

 specimens and juveniles of Nesiarchus. The great variability in 

 vertebral counts suggests that more than one species exists in 

 the genus Nesiarchus. 



Gempylus serpens (Fig. 318).— The larvae of Gempylus are 

 known. Liitken (1880) figured four post-larvae and juvenile G. 

 serpens. We believe that these were correctly identified because 

 at least 6 finlets are present on all but the smallest specimens. 

 Voss (1954) described 2 series of Gempylus larvae. Her Gem- 

 pylus A is Diplospinus and Gempylus B is G. serpens. Eight 

 larvae from 4.4 to 1 1.6 mm were described and the 5.1 mm 

 specimen in fig. 3A is a G. serpens not a Nesiarchus. Gempylus 

 serpens larvae can be distinguished from other gempylid larvae 

 by having a distinct line of lateral body pigment and up to 4 

 rays in the pelvic fin. The preopercular spines of Gempylus are 

 smooth, but the first dorsal and pelvic fin spines are serrate. 

 Late larvae and juvenile Gempylus develop 6 or 7 dorsal and 



