SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1713984f41b62fa7139dbd94a55853231678e75f6dfb0b6b016a0c953bf0721d' 
  AND token = 'hOJxSq5+lU5Z54UoKHKpYVi7rM+LrLH943cBfXOYIS0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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