John Gill Commentary 1 Chronicles 2:54

"The sons of Salma: Beth-lehem, and the Netophathites, Atroth-beth-joab, and half of the Manahathites, the Zorites." — 1 Chronicles 2:54 (ASV)

The sons of Salma
Another son of the younger Caleb, (1 Chronicles 2:50 1 Chronicles 2:51) whose sons were Bethlehem, the inhabitants of the place, at least many of them, of which he was prince, (1 Chronicles 2:51) and the Netophathite; the inhabitants of Netophah, a place in the tribe of Judah, mentioned along with Bethlehem, (Nehemiah 7:26) these sprung from Salma:

Ataroth, the house of Joab ;
Ataroth seems to be the name of a place in the tribe of Judah, where the family of Joab lived, the inhabitants of which were the descendants of Salma:

and half of the Manahethites ;
the other half of the inhabitants of Manahath, see (1 Chronicles 2:52) ,

the Zorites ;
part also of them, called Zareathites, (1 Chronicles 2:53) .