Mentioned in Paus. 6.13.10, these unnamed sons of Pheidolas were presumably from Corinth, like their father (Paus. 6.13.9). Pausanias asserts they won 2 Olympian and an Isthmian victory in horse racing (keles hippos). I follow Farrington (2012), no. 1.22 and p. 105-6 note 220 for the dating: he makes use of Pausanias' mention of Olympian records, which suggest one of the Olympian victories occurred in 508 B.C. - estimating the career of a racing horse, Farrington suggests the victories fall between 512-504. - PK
Lycus the horse of the sons of Pheidolas won twice at the Olympic games and once at the Isthmian games, according to an inscription at Olympia seen by Pausanias. However, Pausanias could only find a single victory of Pheidolas' sons in the Olympic archives. Moretti 1957, no. 152 suggests therefore that one of the Olympic victories refers to the one of their father, Pheidolas, and thus attributes only one victory to the sons of Pheidolas, rather than two. But: Pausanias (6.13.9; also this database: 108) gives another name of the horse (Aura), with which the father had won his race. There remains a problem.
One of the victories, anyhow, dated to the 68th Olympiad (= 508 BC), following Pausanias. - DL