The Black-bellied Sandgrouse can be confused with the Pin-tailed Sandgrouse, only that the latter has a white belly while the Black-Bellied Sandgrouse has a black one. On the other hand, the Pin-tailed Sandgrouse has central rectrices (R1) of great length (crests) in males, something that the Black-Bellied Sandgrouse lacks.
Adult males have a grayish-peach colored head and chest. Colors such as amber-orange-brown converge in their throat. The primaries of these specimens are a gray-bluish color as well as the primary coverts. The greater coverts are golden, with gray spots.
Females have a head, chest, and back that is fawn-colored with black or dark brown spots. The throat area has very blurred small spots and at the end of the chest, a large black line in the form of a bib. The primaries of adult females are gray-bluish, although perhaps with a more brownish touch than the males. On the innermost primaries there is a margin of whitish color. The median and lesser coverts with a streaked/spotted pattern that is suitable for camouflage with the environment.
It is possible to recognize 3 different ages:
Juvenile specimen: they have a feather pattern very similar to that of the female, only with new feather, that is, without any wear. The primaries have the border that the females have white, but in this case it would be dark ocher vermiculated.
1st – 2nd year specimen: with an image similar to the adult, but preserving the three outermost primaries (P10, P9, P8) of juvenile type, now worn.
Adult specimen: with the design described in the SEXING category.
The Black-bellied Sandgrouse performs a complete postnuptial molt that begins in May and usually ends in October. Non-adult specimens perform a very complete postjuvenile molt that, with the exception of some outermost primaries, usually change all their feathers. This molt usually starts in August.
Primaries: 10 per wing.
Secundaries: 16-17 per wing.