NO. 3582 GENUS ENTOMACRODUS — SPRINGER 131 



pectoral fin formulae, 15 and 14 respectively, could apply only to 

 E. nigricans. The color description is applicable to E. nigricans 

 and positively excludes 0. a. macclurei. I therefore place E. decoratus 

 in synonymy with E. nigricans and ascribe Poey's dorsal fin formula 

 to an error. 



Relationships.— E'wiomacrot/ws nigricans is most closely related 

 to the Atlantic Ocean species E. cadenati, E. textilis, and E. vomerinus 

 and the Pacific Ocean species E. caudofasciatus (also Indian Ocean), 

 E. sealei, E. corneliae, and E. chiostictus (the E. nigricans species 

 group) (see "Relat'onships" under E. chiostictus). All these species 

 have the crenulations of the upper lip predominantly restricted to 

 the lips' lateral thirds. Of this group the Atlantic species appear 

 to be most closely interrelated. I base this conclusion on certain 

 similarities of color pattern (the basic lip pattern of 7-10 dark stripes), 

 relative lengths of the supraorbital cirri, and the usual presence of 

 only simple pores in the preopercular series. Entomacrodus nigricans 

 differs from E. cadenati in having the lip stripes as solid lines, whereas 

 E. cadenati has the stripes as a series of more or less vertically arranged 

 spots. The peculiar U-shaped black marking behind the eye in 

 E. cadenati also distinguishes that species from E. nigricans, where 

 the marking is not present. The lateral line pores of E. cadenati and 

 E. textilis usually terminate farther posteriorly than those of E. 

 nigricans. E. nigricans is further distinguished from E. textilis in 

 that E. nigricans lacks the black humeral blotch of the latter. It 

 differs from E. vomerinus in having typically fewer dorsal and anal 

 fin rays, fewer gill-rakers, and vertebrae, and, at any given size, 

 usually more predorsal commissural pores. None of the specimens 

 of E. vomerinus examined had any dark spots on the sides in the 

 region below the spinous dorsal as found in E. nigricans. The lip 

 stripes in E. vomerinus are usually not so obvious as those in nigricans. 



Many recent writers have considered all four Atlantic species of 

 Entomacrodus that I recognize as conspecific, under the specific name 

 textilis (combined with Alticus, Riipiscartes, Salarichthys , or Ento- 

 macrodus) . Although the differences between the species as conceived 

 here are not great, my reasons for recognizing them as distinct are as 

 follows: On the basis of color pattern and/or meristic characters, four 

 distinct, homogeneous groupings (popidations) of specimens are dis- 

 cernible; each of these four groupings is restricted to a particular 

 geographic range well separated from that of any of the others; the 

 ranges, except for the Ascension-St. Helena area, are extensive, 

 covering several thousand mUes of latitude and/or longitude, which 

 indicates long term stability of the populations. The sum of these 

 reasons implies isolation and fixation of subsequent divergences of 

 each population. It is assumed that the immense distances separating 



