412 



PATAGONIAN EXPEDITIONS! ZOOLOGY. 



PSEUDACANTHICUS Bleeker. 



Type: Hypostomus serratus Cuvier & 



Valenciennes. 



Range: Amazon to Surinam, 

 l. Pseudacanthicus serratus (Cuvier & Va- 

 lenciennes) , Regan, 260. 



Habitat: Surinam. 



A2. Pseudacanthicus spinosus (Castelnau), 



Regan, 260. 

 Habitat : Amazon. 

 3. fseudacanthicus fordii (Giinther), 



Regan, 261. 

 Habitat: Surinam. 

 A4. Pseudacanthicus hystrix (Cuvier & 



Valenciennes), Regan, 261. 



Habitat: Rio Negro. 



LlTHOXUS Eigenmann MS. 



Type: Lithoxus lithoides Eigenmann. 

 Range that of the single species, 

 i. Lithoxus lithoides Eigenmann MS. 



Habitat: Cataracts of British Guiana. 



ACANTHICUS Spix. 



Type: Acanthicus hystrix Spix. 

 Range that of the single species. 

 Ai. Acanthicus hystrix Spix, Regan, 262. 

 Rhinelepis acanthicus Cuvier & Valen- 

 ciennes. 

 Habitat: Amazon; Guiana. 



HYPOPTOPOMA Giinther. 



Type : Hypoptopoma thoracatum Giin- 

 ther. 



Range : Upper Amazon. 

 Ai. Hypoptopoma thoracatum Giinther, 



Regan, 263. 



Hypoptopoma bilobatum Cope. 

 Habitat : Upper Amazon. 

 A2. Hypoptopoma joberti (Vaillant), 



Regan, 265. 



Otocinclus bilobatus Steindachner, non 

 Cope. 



Habitat: Upper Amazon; Jurua. 

 Hypoptopoma steindachneri Boulenger. 

 A3. Hypoptopoma thoracatum Steindach- 

 ner, non Giinther. 

 Habitat : Amazons. 

 A4- Hypoptopoma gulare Cope, 



Regan, 265. 

 Habitat : Upper Amazon. 



OXYROPSIS Eigenmann & Eigenmann. 



Aristomata Holmberg. 

 Type : Oxyropsis wrightiana Eigen- 

 mann & Eigenmann -Hypostomus 

 carinatus Steindachner. 

 Range: Upper Amazon and Paraguay. 

 Ai. Oxyropsis carinatus (Steindachner), 



Regan, 264. 



Oxyropsis wrightiana E. & E. 

 Habitat: Upper Amazon. 

 2. Oxyropsis inexpectatus (Holmberg), 



Regan, 264. 



Oxyropsis gilntheri (Boulenger), 

 Habitat: Paraguay. 



OTOCINCLUS Cope. 



Hisonotus Eigenmann & Eigenmann. 

 Type : Otocinclus -ve stilus Cope. 

 Range: Southeastern Brazil, Paraguay 

 and Ambyiacu. 



1. Otocinclus affinis Steindachner, 



Regan, 267. 

 Habitat : Santa Cruz. 



2. Otocinclus vittatus Regan, . . Regan, 267. 



Habitat: Paraguay. 



A3. Otocinclus -vestitus Cope, . . Regan, 267.. 

 Habitat: Ambyiacu. 



4. Otocinclus flexilis Cope, .... Regan, 267. 



Otocinclus fimbriatus Cope. 

 Habitat : Rio Grande do Sul. 



5. Otocinclus leucofrenatus Ribeiro, 



Ribeiro, 1908. 

 Habitat: Ribeira. 



6. Otocinclus notatus (Eigenmann & Eigen- 



mann), Regan, 268. 



