• Postabdominal claw with one basal spine
• Anal groove of postabdomen completely edged by groups of spinules
• The middle setae of the lateral fascicles are the longest in the group
• Three median head pores, with middle pore being closer to posterior pore; lateral pores appear as transversely elongate slits
• Shell color amber to weakly yellow
• Rostrum moderate in length, antenullar setae extend past tip of rostrum

• Alona bicolor forms a compact species group with Alona costata and Alona rustica, and is commonly found with either one or both of the other two species (1).

(1) FREY, D.G. 1965. Differentiation of Alona costata Sars from two related species (Cladocera, Chydoridae). Crustaceana. 8: 159-173.