066 MR. C. TATE REGAN ON 



3G. Descriptions o£ new Fishes o£ the Family Loricariidse 

 in the British Museum Collection. By C. Tate Regan, 

 M.A., F.Z.S. 



[Received March 5, 1912 ; Read April 23, 1912.] 



(Plates LXXY.-LXXYII.*) 



Index. 

 Sj'stematic : Page 



Plecostomus Jiondes, sp. n 666 



ChcBtostomus palmei'i, sp. n 667 



C. lepturus, sp. n 667 



C paucispinis, sp. n 667 



Xenocara heterorliynchus , sp. n 668 



X. muUispinis, sp. n 668 



Otocinclws maculipinnis, sp. n 668 



Oxi/Ioricaria tamancs, STp. n 669 



O. leightotii, sp. n : 669 



Arges cirratus, sp. n 670 



During the last three years several Loricariid fishes hscve been 

 added to the British Museum Collection, including examples of 

 the following ten species new to science. 



1. Pleoostomus hond^, sp. n. (PI. LXXYI. fig. 3.) 



Depth of body 4| in the length, length of head 3. Depth of 

 head If in its length, breadth 1|, snout 1|, eye 7, interorbital 

 width 2J-. Length of mandibular ramus 3 in interorbital width ; 

 jaws with about 12 teeth on each side. Snout ovate; supra- 

 orbital margins slightly raised ; supraoccipital convex, without 

 distinct ridge ; temporal plates not or but feebly keeled. Scutes 

 spinulose, weakly carinate, 27 or 28 in a longitudinal series, 

 7 between dorsal and adipose fin, 13 between anal and caudal; 

 supraoccipital entirely bordered posteriorly by a single scute ; 

 lower surface of head and abdomen with a few scattered granules 

 (probably covered with granular scales in the adult). Dorsal I 7 ; 

 first ray nearly as long as head, last ^ as long; base more than 

 distance from tip of spine of adipose fin. Anal I 4. Pectoral 

 spine extending to anterior | of ventrals. Caudal emarginate, 

 the middle rays | as long as the outer ones, which are longer 

 tban the head. Caudal peduncle 3 times as long as deep. 

 Reddish brown, with traces of darker spots on head and anterior 

 part of body ; dorsal red, with three series of dark spots between 

 the rays ; caudal with alternate red and dusky bars ; lower fins 

 reddish, with dark spots. 



Two specimens, 80 mm. in total length, from Honda, Colombia 

 (300-400 ft.), presented in 1909 by Sir Bryan Leighton, 



* For explanation of the Plates see p. 670. 



