SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6e85a0eb7ff0ea137f872bf451836c99f0f6ad9556b0bf3621c1324dc726780b' 
  AND token = 'ROtxMSVALn0rBKzGRxemn6XnxxdWgaAn/LtA/rSuhYk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00050

JSON explain

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