FISHES OF THE FAMILY LOEICARIID^. 271 



Key to the Species. 



I. Lips both well developed, papillose, with short marginal fringes ,- barbel not, or not much, 

 longer than diameter of eye; teeth in equal number in both upper and lower jaw, 6-10 

 on each side ; a more or less distinct enlarged anal plate or pair of plates. (Rhineloricaria 

 Blkr.) 

 A. Abdomen completely covered with plates to the level of the base of pectoral or beyond. 



1. Supraoccipital with 1 or a pair of serrated keels ; lateral keels sharp, separate through- 



out ; abdomen with 2 or 3 series of plates between the lateral series ; uppermost 

 caudal ray elongate. 

 31-32 scutes in a longitudinal series ; anal plate bordered anteriorly 



by several 1. L. filamentosa Stdr. 



29 scutes in a longitudinal series ; anal plate bordered anteriorly 



by 3 2. L. nigricauda Rgn. 



2. Supraoccipital with weak or obtuse keels or none ; lateral keels weak or obtuse, 



usually completely united posteriorly. 



a. Both outer rays of caudal produced (? L. phoxocephala) ■ a blackish stripe on each 



side of the snout running forward from the eye ; 28-30 scutes in a longitudinal 

 series ; abdomen with 3 or 4 series of plates between the lateral series ; breadth 

 of head lf-1^ times in its length. 

 Diameter of eye 6^ times in the length of head, interorbital width 

 3-3^ times (in a specimen of 100 mm.) ; snout rounded 

 anteriorly. Pectoral spine extending to anterior } of ventral. 3. L. parva Blgr. 

 Diameter of eye 7 times in the length of head, interorbital width 

 3J times (in a specimen of 140 mm.) ; snout pointed. 



Pectoral spine extending to base of ventral or a little beyond. 4. L. phoxocephala Eigmn. 

 Diameter of eye 9 times in the length of head, interorbital width 

 3-3£ times (in a specimen of 130 mm.). Pectoral spine not 

 reaching base of ventral 5. L. lanceolata Gthr. 



b. Uppermost ray of caudal very stout and strong, apparently not produced ; 28-30 



scutes in a longitudinal series; abdomen with 3 or 4 series of plates between 

 the lateral series. 

 Breadth of head l|-lf times in its length, length of snout lf-2 



times; pectoral spine extending to base of ventral . ... 6. L.jubata Blgr. 

 Breadth of head 1 J-lf times in its length, length of snout 2-2£ 

 times ; pectoral spine extending §— f of the distance from its 

 origin to the ventral 7. L. uracantha Kner & Stdr. 



c. Uppermost ray of caudal produced (? L. cadea and L. konopickyi) . 25-30 scutes in 



a longitudinal series ; abdomen with 3 or 4 series of plates between the posterior 

 ones of the lateral series. 

 a. Scutes in front of dorsal not or very obscurely carinate. 

 Breadth of body at level of first anal ray about 5 times in the 

 distance from that point to the caudal ; first dorsal ray as 

 long as or a little longer than the head ; interorbital width 

 vol. xvii. — part. in. No. 11. — October, 1904. 2 o 



