SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f69d3277a966c786ba5f2a14acaa3271e660ee0a71b5a25c3de7fe29d5b3eefe' 
  AND token = 'kBosLxC59KwuwZmLtZNxwHBxNPFOJKqb+nGhRSxVnbs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}