''Isocarpha megacephala'' is a New World species of plants in the family

Asteraceae The family Asteraceae, alternatively Compositae, consists of over 32,000 known species of flowering plants in over 1,900 genera within the order Asterales. Commonly referred to as the aster, daisy, composite, or sunflower family, Compositae ...

. It has been found only in northeastern

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

(

Bahia Bahia ( , , ; meaning "bay") is one of the 26 states of Brazil, located in the Northeast Region of the country. It is the fourth-largest Brazilian state by population (after São Paulo, Minas Gerais, and Rio de Janeiro) and the 5th-largest ...

Pernambuco Pernambuco () is a state of Brazil, located in the Northeast region of the country. With an estimated population of 9.6 million people as of 2020, making it seventh-most populous state of Brazil and with around 98,148 km², being the ...

Paraíba Paraíba ( Tupi: ''pa'ra a'íba''; ) is a state of Brazil. It is located in the Brazilian Northeast, and it is bordered by Rio Grande do Norte to the north, Ceará to the west, Pernambuco to the south and the Atlantic Ocean to the east. Paraíb ...

).David J. Keil & Tod F. Stuessy. 1981. Systematics of ''Isocarpha'' (Compositae: Eupatorieae). Systematic Botany (1981) 6(3): pp. 258-287
descriptions, line drawings, distribution maps for all 5 species ''Isocarpha megacephala'' is an annual or perennial herb up to tall. Leaves are up to long. One plant produces several flower heads, each across (thus larger than the other species) each head on a long flower stalk, each head with 200-300 white disc flowers but no ray flowers.

References

Eupatorieae Endemic flora of Brazil Plants described in 1925 {{Eupatorieae-stub