Thought I would put this lepomis traits here and in the sunfish archive. From Wisc Fish an outstanding site with great work. It has pics of the traits and pics of some crosses.
http://www.seagrant.wisc.edu/home/Default.aspx?tabid=605&FishID=21Compare Similar Species
Lateral Scales
Bass, Rock 39-43
Bluegill 39-45
Pumpkinseed 38-43
Sunfish, Green 44-51
Sunfish, Longear 34-38
Sunfish, Orangespotted 36-41
Warmouth 36-40
Opercular Flap Color
Bass, Rock Solid dark
Bluegill Solid dark
Pumpkinseed Dark with light spot at tip
Sunfish, Green Dark with light margin
Sunfish, Longear Dark with light margin
Sunfish, Orangespotted Dark with light margin
Warmouth Dark with light margin
Gill Rakers
Bass, Rock 7-10, long and thin
Bluegill 13-16, moderately long
Pumpkinseed 9-12, short and thick
Sunfish, Green 11-14, long and thin
Sunfish, Longear 9-11, short and thick
Sunfish, Orangespotted 10-15, long and thin
Warmouth 9-12, moderately long
Pectoral Fin
Bass, Rock Short, rounded
Bluegill Long, pointed
Pumpkinseed Long, pointed
Sunfish, Green Moderately long, rounded
Sunfish, Longear Short, rounded or blunt point
Sunfish, Orangespotted Long, rounded or blunt point
Warmouth Moderately long, rounded
Pigment Pattern on Sides and Soft Dorsal Fin
Bass, Rock Sides brown solid color or with dark mottling or many indistinct spots; fin mottled and/or spotted
Bluegill Sides dark or silver blue or bluish-olive, solid color or with dark vertical bars, sometimes fine irregular dark blue spots; fin solid, often with large diffuse spot at base
Pumpkinseed Sides olive or yellow-olive, with many irregular yellow-orange spots or blotches and sometimes faint vertical bars; fin solid or faint spots/mottling
Sunfish, Green Sides yellow or blue-green, with solid color, dark mottling, faint light spots or faint dark bars; fin dusky, spotted or with dark blotch at base
Sunfish, Longear Sides dark bluish-olive, with solid color or light irregular spots or blotches/mottling; fin solid or faint spots/mottling
Sunfish, Orangespotted Sides blue or gray, with occasional irregular orange spots, faint diffuse vertical bars; fin solid or faint spots/mottling
Warmouth Sides yellow-brown or olive with dark mottling, faint spots or faint bars; fin mottled and/or spotted
Other Characteristics
Bass, Rock 5-7 anal spines; 9-11 anal rays
Bluegill Opercular flap slightly elongated in large adults
Pumpkinseed None
Sunfish, Green Rarely a few teeth on tongue
Sunfish, Longear Opercular flap greatly elongated in adults
Sunfish, Orangespotted Opercular flap often elongated in adults; large sensory pores above lip; 8-9 anal fin rays
Warmouth Well-developed supramaxillary bone; teeth on tongue
Similarity Index
Bass, Rock Moderately similar
Bluegill N/A
Pumpkinseed Small juveniles very similar, adults moderately similar
Sunfish, Green Small juveniles very similar, adults moderately similar
Sunfish, Longear Small juveniles very similar, adults moderately similar
Sunfish, Orangespotted Small juveniles very similar, adults moderately similar
Warmouth Small juveniles very similar, adults moderately similar
This may help - lepomis id chart