Eurycheilichthys, Reis & Schaefer, 1993

Reis, Roberto E., 2017, Unexpectedly high diversity in a small basin: A taxonomic revision of Eurycheilichthys (Siluriformes: Loricariidae), with descriptions of seven new species, Neotropical Ichthyology 15 (1), No. e 160068, pp. 1-28 : 3

Key to species of Eurycheilichthys

1. Body color plain dark brown, without blotches or spot, and with light stripe extending posteriorly from snout tip, medial to eye and onto predorsal area .................... 2

1’. Body color with a different combination of dark blotches and spots ....................................................................... 3

2. Both upper and lower lobes of caudal fin completely brown; spine and rays of the dorsal fin plain brown ....... ..................................................................... E. castaneus

2’. Lower lobe of caudal fin brown and upper lobe mostly hyaline; spine and rays of dorsal fin spotted ... E. limulus

3. Abdomen naked ventrally ( Fig. 2h); head and predorsal region distinctly flat posterior to orbits ........... E. planus

3’. Abdomen with plates ( Figs. 2 a-g, i); head, and predorsal region elevated posterior to orbits................................. 4

4. Abdomen with irregular series of platelets medially, or incompletely covered by granular platelets embedded in skin and leaving naked areas laterally on abdomen ( Figs. 2f, i) ............................................................................... 5

4’. Abdomen extensively covered by plates ( Figs. 2 a-e, g)... 6

5. Body and head covered by many small, roundish, dark spots; lower lip large, reaching to, or beyond, anterior margin of pectoral girdle ................................... E. luisae

5’. Body with large, irregular dark spots, head mostly dark without conspicuous spots; lower lip narrow, not reaching anterior margin of pectoral girdle .................. ............................................................... E. vacariensis

6. Lower lip extending beyond anterior margin of pectoral girdle; body and head covered by many regularly small and roundish dark spots............................ E. pantherinus

6’. Lower lip not reaching or just reaching to anterior margin of pectoral girdle; spots on head and body absent, or if present, irregular in size and shape ............................... 7

7. Body color with uniformly brown background and occasional darker blotches; parieto-supraoccipital conspicuously elevated ( Fig. 3); first pelvic-fin ray short (length 64.4-80.2% of pectoral-fin spine); 25-26 plates in middle lateral series................................ E. coryphaenus

7’. Body color with light background and many dark blotches; parieto-supraoccipital without conspicuous elevation; first pelvic-fin ray long (length 80.6-100.6% of pectoral-fin spine); 27-30 (occasionally 26) plates in middle lateral series....................................................... 8

8. Few (2-10) accessory teeth on premaxilla in one irregular series............................................................ E. paucidens

8’. Numerous (27-38) accessory teeth on premaxilla in several irregular series.............................. E. apocremnus