FISHES OF THE GULF OF MAINE 333 



126. Alligatorfish (Aspidophoroides monopterygius Bloch) 

 Seapoacher 



Jordan and Evermann, 1S96-1900, p. 2091. 



Description. — The readiest field marks for the identification of this curious 

 little fish, so odd in appearance that it is not likely to be mistaken for any other, 

 are that its entire head and body are clad with bony plates, that there is only one 

 dorsal fin (the soft rayed), and that it is very slender (about 12 to 13 times as long as 

 deep, not counting caudal), rather thicker than deep, and tapers rearward from 

 the head to a very slender caudal peduncle. The plates are smooth, arranged in 

 longitudinal rows as follows: A double row on the back running from the base 

 of the head to just behind the dorsal fin where they unite into a single dorsal row 

 (altogether 45 to 50 double and single plates along the back), two rows on each 

 side, and two along the lower surface to just behind the anal fin, where they unite 

 in one row. Thus the trunk is octagonal in front of the unpaired fins and hex- 

 agonal behind them. There are likewise two large and several small plates in front 

 of each pectoral fin. The eyes are very large, with prominent ridges above them, 

 and there are two sharp recurved spines on top of the nose. The mouth is small 

 with minute teeth. The dorsal and anal fins (each of 5 or 6 rays) are fanshaped, 





Fig. 161. — Alligatorfish (Aspidophoroides monopterygius) 



one over the other about midway of the trunk. The caudal fin is small and 

 rounded, the pectorals are larger than the unpaired fins, and the ventrals are 

 reduced to one spine and two rays each. 



Color. — The few we have seen have agreed with the published descriptions 

 in being brown above with five or six darker brown or black crossbands and paler 

 brown below. 



Size. — Five to six inches long. 



General range. — From west Greenland and the northeast coast of Labrador 

 southward to Rhode Island and New Jersey. 



Occurrence in the Gulf of Maine. — Being of no interest to fishermen, and living 

 too deep to strand on the beach, this fish is seldom reported. It has been taken 

 in 15 to 100 fathoms in the Bay of Fundy and in Passamaquoddy Bay, at Eastport, 

 in 60 fathoms off Monhegan, near Portland, in 30 fathoms off Casco Bay, in Ips- 

 wich Bay, off Gloucester, Nahant, and Boston in Massachusetts Bay, off Prov- 

 incetown, and off Cape Cod, records enough to show that it may be expected 

 anywhere in the Gulf in depths of 10 to 100 fathoms and perhaps deeper. Goode 

 and Bean (1879, p. 13) described it as abundant in the deeper parts of Massa- 

 chusetts Bay, but our experience on the Grampus suggests "not uncommon" as 

 a better description, our largest catches being 8 and 6 specimens from 32 fathoms 



