Sex-chromosome-evolution
Guides
Danaini
Tiger and Crow Butterflies, Tiger butterflies
Danaini is a tribe of brush-footed butterflies within the milkweed butterfly subfamily Danainae. The tribe includes approximately 300 species across multiple subtribes, most notably Danaina (containing the monarch butterfly Danaus plexippus and related tiger butterflies) and Euploeina (containing crow butterflies and tree nymphs). Members are characterized by reduced forelegs, bright aposematic coloration, and associations with plants containing defensive compounds. The tribe lacks a fixed colloquial name, though 'tiger butterflies' is occasionally applied to subtribe Danaina.
Eulimnadia
clam shrimp
Eulimnadia is a genus of small freshwater branchiopods commonly known as clam shrimp. The genus is notable for its rare androdioecious mating system, where populations consist of males and hermaphrodites but lack pure females. This reproductive strategy has persisted for an estimated 24–180 million years across multiple speciation events, making it one of the most stable examples of androdioecy known in animals. Species are distinguished primarily by the morphology of their resting eggs (cysts), which show distinctive sculpturing patterns. The genus contains approximately 13–25 described species with a cosmopolitan distribution across every continent except Antarctica.