118 PROCEEDINGS OF THE NATIONAL MUSEUM vol. iie 



orbital 3.2 (31.0%) [4.0 (25.2%)], USNM 3.1 (32.0%), SU 3.5 

 (28.4%) in head length. Snout acute in dorsal view. Snout tip 

 rounded in lectotype, much more acute in SU 35054 (a poorly pre- 

 served, dehydrated specimen). Snout 1.4 (70.4%) [1.5 (66.4%)], 

 USNM 1.6 (64.0%), SU 1.5 (64.9%) in head length. Dorsal profile 

 of snout slightly concave in all specimens. When directed posteriorly, 

 both upper rictal (actually maxillary) and lower rictal barbels reach 

 a point on a vertical about half an orbital diameter behind posterior 

 edge of the orbit. Greatest diameter of bony orbit 3.8 (26.1%) 

 [4.6 (21.7%)], USNM 4.1 (24.6%), SU 3.9 (25.8%) in head length. 

 Greatest width of suborbital 2.3 (43.3%) [1.5 (67.7%)], USNM 1.4 

 (69.8%), SU 2.4 (41.1%) in orbit. 



Dorsal fin I, 7, last fin ray split to its base in all specimens. Spine 

 of dorsal fin when depressed reaching to, or slightly beyond, posterior 

 termination of dorsal fin base, distant from origin of adipose fin. 

 Adipose fin spine in orbit 1.0 (97.4%) [1.0 (100.3%)], USNM 

 1.3 (79.0%), SU 1.2 (84.7%). Anal fin ii,5, last ray split to its base 

 in all specimens. USNM 179612 could be interpreted as ii,6, last 

 fin ray not split to its base. The last two ray elements of the anal 

 fin in this specimen are well separated and probably each ray base 

 belongs to its own separate pterygiophore series. Pectoral fin 

 1,10, [1,11], USNM 1,10, and SU 1,10. Pelvic rays i,5, in all speci- 

 mens. Principal caudal rays 7/7 in all specimens. Pectoral fin 

 spine (see fig. 2) with 16 [18], USNM 21, SU 16, stout spinules along 

 its posterior border. 



Figure 2. — Corydoras treitlii Steindachner. Pectoral fin spine of lectotype, ventral 



view, left spine. 



Color. — The lectotype has the following color pattern in alcohol 

 (see also fig. 1): Basic body color yellowish gray. Head with brown 

 marldngs as shown in figure 1 ; no punctate or vermiculate markings 

 over snout or head. Sides with purplish dark brown markings on 

 upper body scutes. All specimens with all fins hyaline, completely 

 lacking bars, bands, or blotches. All specimens with color pattern 

 very similar to lectotype except that SU 35054 greatly faded. Color 

 in life not known. 



