SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e2f2f058a33a0f5a4553ef85a50ce568feea3773bd9229f125b959653460833f' 
  AND token = '2tOtg2T2c8qapUhHbk1VJz7PINZ6F83wMsqDYhhC1yw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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