SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f1b2bf1255950da1574fb30ddd91fceccbd43195488a440dade489e92380e489' 
  AND token = '2zpi8SDxpuO4up/1y1I2WdXlg5wm0Th+l30JftJrpl0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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