Nikon DSLR + Sigma 24mm f/2.8 manual lens reversed with the classic BR-2A ring.
A flickr contact has made me notice the resemblance to the elytra of some beetles. I do not know if this resemblance is included in some kind of camouflage or just the opposite, causing the seed to be eaten by birds

Best

Semilla de Dondiego de noche - Mirabilis jalapa by Joaquim F. P., en Flickr