Dig deeper at SERNEC, a consortium of southeastern herbaria.

Ludwigia bonariensis is much like L. octovalvis, but with huge flowers (to ~ 2-3" across) and a rather short floral tube, whereas the native L. octovalvis has flowers ~ 1.5" across and a very long floral tube. Read more at Vascular Plants of North Carolina.

SYNONYMOUS WITH PLANTS NATIONAL DATABASE:
Ludwigia bonariensis   FAMILY Onagraceae

SYNONYMOUS WITH Flora of North America north of Mexico, vol. 10 (2021)

Ludwigia bonariensis

SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 137-01-002:

Ludwigia bonariensis   FAMILY Onagraceae

SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)

Jussiaea neglecta

COMMON NAME:
South American Seedbox

NameThatPlant has no pictures at this time. You might try this link: Flora of the Southeastern United States

WEAKLEY'S FLORA OF THE SOUTHEASTERN US (4/24/22):
Ludwigia bonariensis   FAMILY Onagraceae

SYNONYMOUS WITH PLANTS NATIONAL DATABASE:
Ludwigia bonariensis   FAMILY Onagraceae

SYNONYMOUS WITH Flora of North America north of Mexico, vol. 10
Ludwigia bonariensis

SYNONYMOUS WITH VASCULAR FLORA OF THE CAROLINAS (Radford, Ahles, & Bell, 1968) 137-01-002:
Ludwigia bonariensis   FAMILY Onagraceae

SYNONYMOUS WITH Manual of the Southeastern Flora (Small, 1933, 1938)
Jussiaea neglecta