Identifying 3 Common Inshore, Similar-Looking Snappers: Mangrove vs. Schoolmaster vs. Dog Snapper

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Identifying 3 Common Inshore, Similar-Looking Snappers: Mangrove vs. Schoolmaster vs. Dog Snapper

Identifying 3 Common Inshore, Similar-Looking Snappers:  Mangrove vs. Schoolmaster vs. Dog Snapper

     I studied the traits of each of these species at length to figure out which characteristics might be most key.  Forget spine and ray counts – they’re all the same. And color varies considerably within any of these species, so don’t rely too much on that. Also, all three can have that blue streak under the eye. I’ve left out the also common Lane, Mahogany and Yellow snappers because they are easily ID’d by color and patterns. Complete descriptions quoted from FishBase for each of the 3 species are at the end of this report. 

     By the way, for anyone fishing the Atlantic or Gulf coasts, I highly recommend Kells and Carpenter. 2011. A Field Guide to Coastal Fishes from Maine to Texas. It is very ‘Peterson-esque’ with color diagrams that accentuate key features.  It’s no panacea, but a great place to begin ID’ing any new Eastern coastal fish.


     This is by far the most abundant snapper caught by shore anglers in Florida, so it isn’t surprising that it has the most entries on Roughfish. 

     COLOR varies from very dark, brick-red brown to cream colored.  Each scale has a brownish spot in the middle, which is not apparent on darker specimens. Fins are never yellowish.

     The PECTORAL FIN IS SHORTER and does not reach the anus.

     The SCALES ABOVE THE LATERAL LINE begin parallel to the lateral line, but then angle upward obliquely, typically below the mid-dorsal fin.  Peruse the photos on Roughfish: there is considerable variation on exactly where they start angling upward and a few of the animals appear to have completely parallel scales, but most seem to follow this rule.

     The ‘CANINE’ TEETH DO NOT SHOW when the mouth is closed (I can’t see any photos that demonstrate this)

Based on these characteristics, it appears that all but one of the Mangrove Snappers are correctly identified.

     Smurph: looks almost like an albino! (but it’s definitely a Mangrove Snapper)

     crow river roughfisherman: has 2 identical fish that are uniformly dark brown, and both have completely parallel scales above the lateral line. They look weird (maybe because they’re dead?) but seem to be Mangroves nonetheless.

     Dollarbill53: this fish is clearly a mutton snapper.


This one shouldn’t be confused with a Mangrove Snapper but can be confused with the Dog Snapper. 

COLOR varies from very light to dark.  Smaller individuals almost always have yellowish to very yellow fins and 8 light vertical bars (maybe 8 ½ - there is often one confused bar following the obvious 8.

The PECTORAL FIN IS LONG reaching the anus.

The SCALES ABOVE THE LATERAL LINE appear to always be parallel to the lateral line

The CANINE TEETH are supposed to be visible when the mouth is closed, but I can find no examples of this (all the mouths are agape).  I am guessing that this feature is more prominent in the Dog Snapper.

All of the Schoolmasters on Roughfish appear to be properly identified with perhaps MikeB’s photo showing all the key characteristics best.


This one is obviously not as common inshore because it has the fewest entries. Also, nearly half the entries on Roughfish are misidentified.

COLOR is very similar to the Schoolmaster at least among the small fish.

The PECTORAL FIN IS LONG reaching the anus.

All or most of the SCALES ABOVE THE LATERAL LINE angle obliquely upward.

They “usually” have a WHITE TRIANGLE UNDER THE EYE.  The “usually” comes from Kells and Carpenter.  I can find no photos on the internet of a Dog Snapper without this white triangle, but maybe no one wants to post a non-typical animal?  I am inclined to change “usually” to “almost always”.

So I’ll review all the Dog Snappers currently on our site because there aren’t too many of them:

     Dinofish:  has the only photo of an adult Dog.  The white triangle and the dog-like canines (hence the common name) are clearly evident.

     Smurf and Professor Fish:  Both photos show most characteristics clearly.

     Silverlake:  Wow! This fish looks disturbingly like a Schoolmaster, but notice the scales slanting upward above the lateral line, and if you squint, there might be a white triangle under the eye, but the fishes’ face is so light it’s hard to tell. (Anyway, I think it’s still a Dog)

     Drew, rc6750, and meghankelly:  All 3 of these fish are clearly Mangrove Snappers.

Hope this helps some people…

Descriptions below from FishBase:

DOG   Dorsal spines (total): 10; Dorsal soft rays (total): 14-15; Anal spines: 3; Anal soft rays: 8. Preopercular notch and knob weak. One of the pairs of canines in upper jaw notably enlarged, visible even when mouth is closed. Pectoral fins long, reaching level of anus. Scale rows on back rising obliquely above lateral line. Presence of a triangular bar between lower edge of eye and rear of mouth. Back and upper sides olive brown with bronze tinge, sometimes with narrow pale bars; lower sides and belly light reddish with a copper tinge. Young with a horizontal blue line below eye which breaks into a row of spots in adults.

MANGROVE  Dorsal spines (total): 10; Dorsal soft rays (total): 13-14; Anal spines: 3; Anal soft rays: 7 - 8. Dorsal profile of head slightly concave, snout long and pointed. Preopercular notch and knob weak. Scale rows on back parallel to lateral line anteriorly, but rising obliquely posteriorly, below soft part of dorsal fin. Young specimens with a dark stripe from snout through the eye to upper opercle and a blue stripe on cheek below eye.

SCHOOLMASTER  Dorsal spines (total): 10; Dorsal soft rays (total): 14; Anal spines: 3; Anal soft rays: 8. Snout long and pointed, mouth large. One of the upper pairs of canine teeth notably enlarged, visible when mouth is close. Preopercular notch and knob weak. Pectoral fins long, reaching the level of anus. Scale rows on back parallel to lateral line, at least anteriorly. Olive gray to brownish on upper back and sides, with eight narrow, pale vertical bars which may be faint or absent in large adults. A solid or broken blue line which may disappear with growth, runs under the eye.

andy's picture
This is great!

Thanks uconn fishhead for putting this together!  We will add it to the Snapper page to help others identify the Snappers they catch.