SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd18ca653b74f97449acd5cbe5775e4046933b57ad7a2ab880c35f9cfbdcff362' 
  AND token = '6tZXpZQWFw2JZSmzQnD00m12DOGEE7r8/hMjCAjUXQo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00049

JSON explain

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