116 PROCEEDINGS OF THE NATIONAL MUSEUM vol. lie 



Harald Schultz, Sao Paulo, Brazil, for locality data and for collecting 

 the specimens of C. semiaquilus; and to Dr. Herbert Axelrod of Jersey 

 City, New Jersey, for two specimens of C. semiaquilus. I also wish 

 to thank Dr. W. Klausewitz and Mr. Fritz Rossel of the Sencken- 

 bergische Naturforschende Gesellschaft, Natm"-Museum und For- 

 schungs-institut, for the loan of a specimen of C. semiaquilus. 

 The following abbreviations are used: 



NMW — Naturhistorisches Museum, Wien 

 USNM — United States National Museum 

 SU — Division of Systematic Biology, Department of Biological Sciences, 



Stanford University 

 SM — Senckenberg Museum. 



Corydoros treitlii Steindachner 



Figures 1 and 2 



Corydoras treitlii Steindachner, 1906, p. 478 (original description; type locality: 

 mouth of a small stream emptying into the Rio Parnahyba at Victoria, State 

 of Maranhao, Brazil). — Eigenmann, 1910, p. 403 (listed). — Miranda Ribeiro, 

 1911, p. 167 (description copied from Steindachner, 1906). — Regan, 1912, p. 

 210 (description copied from Steindachner, 1906). — Ellis, 1913, p. 407 

 (listed). — Gosline, 1940, p. 15 (aquarium specimen, no description) ; 1945, p. 

 74 (listed). — Stigchel, 1946, p. 129 (description of specimen from original 

 collection). — Bohlke, 1950, p. 27 (discussion of relationships with Corydoras 

 /oa'?m).— Fowler, 1954, p. 67 (listed). 



Lectotype. — NMW 61103, standard length 42.6 mm., collected 

 during 1903 by Franz Steindachner at mouth of brook emptying into 

 Rio Paranhyba [Parnaiba River] at Victoria [Alto Parnaiba], State 

 of Maranhao, Brazil. 



Additional specimens. — NMW 47798, paralectotype, standard 

 length 42.4 mm., same data as lectotype; USNM 176912, standard 

 length 52.5 mm., Sao Paulo, Brazil, Herbert Axelrod, 1958; SU 35054, 

 standard length 47.0 mm., sent to the Division of Systematic Biology, 

 Stanford University, by Mr. Fred H. Stoye in March 1937. Mr. 

 Stoye stated that, according to Mr. N. Greim, this is an aquarium 

 specimen from the Amazon. In my opinion this locality data is 

 uncertain. This is the specimen utilized by Gosline (1940). 



Diagnosis. — Corydoras treitlii may be distinguished from other 

 species of Corydoras by the following combination of characters: 

 Snout long, about 30 to 32% of body length mthout head. Least 

 caudal peduncle depth about 57 to 62% of snout length. Imbricated 

 thoracic and abdominal plates absent; fine bony pricldes present 

 in these regions. Dorsal fin spine about equal in length to pectoral 

 fin spine. Predorsal length about 79 to 89% of distance between 

 dorsal fin origin and caudal fin base. Caudal fin without bars. 



