Key to the Neotropical species of Centrorhynchus

1 - Proboscis armature without transitional hooks..................................................................................................................................................................................2

1’ - Proboscis armature with transitional hooks......................................................................................................................................................................................4

2 - Hooks true with anterior and posterior roots, 24 – 26 longitudinal rows of hooks, 27 – 28 hooks per rows; 16 – 17 + 0 + C. giganteus Travassos 1919

2 ’ - Hooks true with roots of different shape, 26 – 39 longitudinal rows of hooks................................................................................................................................3

3 - Proboscis armed with 26 longitudinal rows of hooks, 20 – 21 hooks per rows; 13 + 0 + 7 – 8 C. tumidulus (Rudolphi 1819)

3 ’ - Proboscis armed with 39 longitudinal rows of hooks, 17 hooks per rows; 5+ 0 + C. nicaraguensis Schmidh & Neiland 1966

4 - Hooks transitional with lateral alate processes, first transitional hook with 4 processes.................................................................................................................5

4’ - Hooks transitional without lateral alate processes............................................................................................................................................................................6

5 - Proboscis armed with 26 – 35 longitudinal rows and 22 – 27 hooks per row; 7 – 9 + 2+ 14-18 ............................................... C. kuntzi Schmidh & Neiland 1966

5’ - Proboscis armed with 32 longitudinal rows and 18 – 19 hooks per row; 8 – 9 + 4 + 6.............................................................................................. C. guira n. sp .

6 - Proboscis armature with up to 30 longitudinal rows of hooks...........................................................................................................................................................7

6’ - Proboscis armature with more than 30 longitudinal rows of hooks................................................................................................................................................8

7 - Proboscis armed with 20 – 22 hooks per rows; 8 + 4 + 10*........................................................................................................................... C. albidus Meyer 1932

7’ - Proboscis armed with 17 hooks per rows; 7 + 3 + 7**................................................................................................................... C. polymorphus Travassos 1925

8 - Proboscis with 32 – 35 longitudinal rows of hooks, 15 – 17 hooks per rows; 8 – 9 + 3 + 4 – 5 C. crotophagicola Schmidh & Neiland, 1966

8’ - Proboscis with 36 – 38 longitudinal rows of hooks, 17 – 18 hooks per rows; 9 + 3 + 5...................................................... C. microcephalus (Bravo Hollis 1947)