SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a83f93baa8f4bd1592f393514bd96e84875dcde8c78fd42d076d598902320200' 
  AND token = 'W30YNtjARDQoSdKzzmXpX9dvnHCc6+PVjOCH99vx0ck=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}