What is "plectocephalus"

Plectocephalus is a genus of plants in the thistle tribe within the daisy family.

1. Plectocephalus americanus (Nutt.) D.Don - Mexico ( Coahuila, Tamaulipas, Nuevo León), United States ( AZ NM TX LA AR MS KS MO IL WI SC NY)
2. Plectocephalus cachinalensis (Phil.) N.Garcia & Susanna - Atacama Region in Chile
3. Plectocephalus chilensis G.Don ex Loudon - Chile
4. Plectocephalus floccosus (Hook. & Arn.) N.Garcia & Susanna - Chile ( Coquimbo + Valparaíso)
5. Plectocephalus rothrockii (Greenm.) D.J.N.Hind - Mexico (from Chihuahua to Chiapas), United States ( AZ NM)
6. Plectocephalus tweediei (Hook. & Arn.) N.Garcia & Susanna - Brazil ( Rio Grande do Sul), Paraguay ( Guairá), Uruguay, Argentina ( Buenos Aires, Chaco, Misiones, Corrientes, Entre Ríos, Formosa)
7. Plectocephalus varians (A.Rich.) - Ethiopia

Plectocephalus dracaenoides (Johow) F.H.Hellw. - Centaurodendron dracaenoides Johow