418 



FISHERY BULLETIN OF THE FISH AND WILDLIFE SERVICE 



A. MONTICOLA 



M. CUREMA 



M. CEPHALUS 



>-j*i!«Vf'iK*'S:'*/'-'' 



Figure 3. — Anal fins from a 29.4-mm. specimen of 

 Affonostomiis monticola, a 30-mm. Miigil curema, and a 

 30-mm. Mtiffil ccphalus. (Camera lueida drawings from 

 cleared and stained specimens.) 



on page 112 in tlieir key to the Mugilidae give 

 2 anal spines for Agonosfomu.s, on page 114 undei" 

 the generic description "Anal spines usually 2, 

 first soft ray slender and often taken for a spine" ; 

 Evermann and Marsh give A. monticoJa an anal 

 fin formula of III, 9. Meek and Hildebrand 

 (1916) on page 333 under the generic description 

 of Agonostomiis state, "anal spines 2, the first one 

 minute, often hidden in the skin"; and on page 

 334, they show an anal fin formula of II, 10 for 

 A. monticola. Hubbs (1944) on page 72, in his 

 discussion of the anal fins of various fish, reports 

 that Mugilidae, "Instead of having only one thin 

 flexible anal spine all mugilids have 2 thick pun- 



gent anal spines, and the third ray with age trans- 

 forms (in the Mugilinae but not in the Agonos- 

 tominae) from a flexible, paired, articulated soft 

 ray into a pungent, solid, unsegmented spine 

 (Jacot, 1920:207-208)." Schultz (1949, p. 112) 

 gives an anal fin count of III, 9 for specimens of 

 A. monticola from Venezuela. Carr and Goin 

 (1955, p. 83) give an anal fin count of III, 9 for 

 specimens from Florida. 



The 34 specimens I have examined (ranging 

 from about 24 to 119 mm. standard length) have 

 only two anal spines. The third ray, even in the 

 largest specimens, shows no evidence of trans- 

 forming into a solid unsegmented spine ; the seg- 

 ments in this slender ray are difficult to see unless 

 examined under magnification. 



Pectoral: — Of the 34 specimens examined, 3 

 had 14 rays, 26 had 15 rays, and 5 had 16 rays. 

 Placement, shape, and extension of this fin are 

 illustrated in figure 2. 



Caudal: — The caudal skeleton of a cleared and 

 stained specimen (29.4 mm. standard length) is 

 illustrated in figure 4. There are 14 principal 

 rays of which 12 branched ; and 19 secondary rays, 

 9 dorsal and 10 ventral. Of interest, at this size, is 

 the peculiar branching of the 8 middle principal 

 rays, which end in three tips (as do the last dorsal 

 and anal fin rays). In M. curem,a and M. cepha- 

 lus at comparable size, the 8 middle caudal rays 

 and the last dorsal and anal rays end in 4 tips. 



PREMAXILLARY, MAXILLARY, AND PREORBITAL 

 BONES 



Schultz (1946) in his revision of the genera of 

 the family Mugilidae pointed out the importance 

 of these bones in separation of the various genera. 

 In figure 5 are illustrated these bones from cleared 

 and stained specimens: a 29.4-mm. .4. monticola 

 and 30-mm. M. curema and M. cephalus. The 

 great similarity of these bones in the two members 

 of Mttgil is striking, as are their differences from 

 A. monticoln (which has a very wide, serrated 

 posterior margin; tips of maxillary and pre- 

 maxillary extending farther below the posterior 

 margin of preorbital ; a deep hook about midway 

 on the rear edge of premaxillary ; and entirely 

 difl'erent shape of tips of maxillary and pre- 

 maxillary). In some larger specimens of .4. 

 monticola thei-e are serrations along the front 

 edge of the preorbital in addition to those along 

 the posterior edge (serrations on the posterior 

 edge vary from about 9 to 13). 



